Department of Mechanical Engineering University of Canterbury …gasnz.org.nz/uploads/feb2018/Earthquake-restraint-of-LPG... · 2018. 3. 4. · Department of Mechanical Engineering

Department of Mechanical Engineering

University of Canterbury

Te Whare Wānanga o Waitaha Telephone: +64-3-366 7001

Private Bag 4800 Facsimile: +64-3-364 2078

Christchurch 8041, New Zealand

Website: www.mech.canterbury.ac.nz

27/10/2017

Peter Gilbert

LPG Association

49 Boulcott Street,

Wellington 6011

Dear Mr. Gilbert,

Project Proposal: LPG Twin Pack Earthquake Testing

The LPG Twin Pack Team is submitting the attached Final year report. The report details the achievements

to date and the final results. It covers the scope changes, testing procedures, testing results and the final

solutions from the testing. In addition, a summary of the project budget is included.

The focus of the project was to test and validate the current securing method of LPG cylinders on buildings

during earthquakes in New Zealand. We have conducted tensile and impact testing to prove the strength

of the current securing methods. For each house cladding material a set of fasteners and bracket type

have been recommended to insure the security of the LPG cylinders during common earthquakes in New

Zealand. A newly improved bracket was designed to increase the strength of some of the weaker cladding

materials.

A finite element analysis was completed to simulate how the cylinders moved from earthquake loading

conditions. This was also used to determine the reaction forces on the brackets fastened to the buildings.

The larger 220 kg LPG cylinder was also simulated.

We hope the results from our project will be of great value to you and we have really enjoyed the

experience of completing a real life-engineering problem.

Regards, Jack Elliott, Nic Cammell, Tim Stone and Dom Evans

LPG Twin Pack Team Encl: End of Year Report Gantt Chart Budget

http://www.mech.canterbury.ac.nz/

1 Executive Summary There is a demand for validation on whether the current securing methods of LPG cylinders on domestic

houses are safe under the earthquakes in New Zealand. The goal was to prove the current methods are

strong enough and if they are not sufficient, a new improved design was to be proposed. In addition, the

larger 220 kg cylinder stability while unrestrained was investigated. This report outlines the research into

the problem and how the testing was executed with, the conclusions and solutions presented.

Most commonly, LPG cylinders are set up against the side of a house and secured using a chain around

them. The chain is held either by a galvanised ‘L’ bracket or by a hook screw. These two methods were

investigated under earthquake loading. A range of different house claddings were tested and different

fasteners were associated with each material. Testing procedures completed, included a series of tensile

tests and impact loading tests. The tensile tests involved using an MTS machine and loaded each test

specimen until failure occurred. The maximum force reached was recorded for each material. The impact

tests involved dropping a known mass from different heights to induce an impact load on the fasteners

and cladding material. The drop height and measured accelerations were related back to earthquake

loads.

The results were compared to the 2011 Christchurch earthquake of 1.25 g peak ground acceleration and

the safety of each fastener and cladding material was determined. Recommended fasteners have been

specified for each material and how these fasteners must be installed in order to be safe in a large-scale

earthquake. It was found that materials like poly-plaster and Hardies board proved to perform poorly and

were failing below the chosen failure criteria load. A new ‘T’ bracket was designed and improved the

performance of the weaker materials.

All the materials tested proved to be strong enough under the earthquake loading except for 7mm thick

plaster over polystyrene. The 6 mm thick Hardies board was made safe using the new improved 'T'

bracket. A set of recommended fasteners and preparation considerations have been stated for each

material to ensure the security of the LPG cylinders.

A shake table test was planned from the beginning of the project to verify results. However, this was

changed to a series of more repeatable impact and static tests because of time and cost restraints. Instead,

a finite element analysis has been completed to show the movement of the LPG cylinders during an

earthquake.

The project was budgeted at costing $1386 in May of 2017 and the final budget came to $1408.

Table of Contents 1 Executive Summary ............................................................................................................................... 2

2 Introduction .......................................................................................................................................... 5

3 Project Scope ........................................................................................................................................ 5

4 Achievements ........................................................................................................................................ 6

4.1.1 Site Visits ............................................................................................................................... 6

4.2 Earthquake Research .................................................................................................................... 7

4.3 Earthquake Calculations ............................................................................................................... 7

4.4 Testing Rigs ................................................................................................................................... 8

4.5 Energy Calculations ....................................................................................................................... 8

4.6 Chain Test ...................................................................................................................................... 9

4.7 Material Preparation ................................................................................................................... 10

4.7.1 Material Research ............................................................................................................... 10

4.7.2 Sample Preparation............................................................................................................. 10

4.8 MTS Testing ................................................................................................................................. 10

4.9 L Bracket Performance ................................................................................................................ 11

4.10 Alternate Securing Methods ....................................................................................................... 12

4.11 FEA of T and L Brackets ............................................................................................................... 12

4.12 Impact Testing ............................................................................................................................. 13

4.13 Recommended Fasteners ........................................................................................................... 15

4.13.1 Brick ..................................................................................................................................... 15

4.13.2 Timber Weatherboard ........................................................................................................ 15

4.13.3 Palliside (PVC Weatherboard) ............................................................................................. 16

4.13.4 ColorSteel ............................................................................................................................ 16

4.13.5 Concrete Block .................................................................................................................... 16

4.13.6 Hardies Board 6 mm ........................................................................................................... 16

4.13.7 Poly-Plaster 9 mm thick ...................................................................................................... 17

4.14 Shake Table Plan ......................................................................................................................... 17

4.15 Earthquake Simulation ................................................................................................................ 18

5 Schedule .............................................................................................................................................. 18

6 Budget ................................................................................................................................................. 20

7 Implications ......................................................................................................................................... 21

8 Conclusions ......................................................................................................................................... 21

9 Future Issues and Limitations ............................................................................................................. 21

10 Ethical Issues ................................................................................................................................... 22

11 Contribution Statements ................................................................................................................ 22

12 References ...................................................................................................................................... 23

13 Recommendations to Client ........................................................................................................... 23

14 Appendices ...................................................................................................................................... 24

14.1 APPENDIX A (FEA Analysis on L and T brackets) ......................................................................... 24

14.2 Appendix B .................................................................................................................................. 29

14.2.1 MTS test Rig design ............................................................................................................. 29

14.2.2 Impact test rig Design ......................................................................................................... 29

14.2.3 FEA simulation of Impact rig ............................................................................................... 30

14.2.4 MTS Material holder FEA .................................................................................................... 35

14.3 Appendix C (Alternative Design) ................................................................................................. 38

14.4 Appendix D (Fasteners) ............................................................................................................... 39

14.4.1 Nylon plug technical data ................................................................................................... 39

14.4.2 Appendix D (selection guide) .............................................................................................. 40

14.5 Appendix E (Material Data) ......................................................................................................... 42

14.6 Appendix F (Manufacturing drawings)........................................................................................ 44

14.6.1 Impact testing ..................................................................................................................... 44

14.7 Appendix G (Tensile Testing Raw Data) ...................................................................................... 56

14.8 Appendix H (Impact testing, T bracket Raw Data) ...................................................................... 59

14.9 Appendix I (Impact testing, L bracket Raw Data) ........................................................................ 64

14.10 Appendix J (L bracket Loading Tables) .................................................................................... 71

14.11 Appendix K(T bracket Loading Tables) .................................................................................... 76

14.12 Appendix L (Impact testing Procedure) .................................................................................. 80

14.13 Appendix M : E2 External Moisture Building Code, Section 9.7 ............................................. 81

14.14 Appendix N: Heathcote Valley Primary School Station Information ...................................... 82

14.15 Appendix O: Heathcote Valley Primary School 2011 Earthquake Plots .................................. 82

14.16 Appendix P (Rockcote PolyPlaster preparation steps) ............................................................ 83

2 Introduction The following report was conducted by the LPG Twin-Pack Final Year Project Team from the University of

Canterbury. The aim of the project was to investigate the current restraint methods of securing LPG

cylinders to domestic houses in earthquakes. Specifically, the 45 kg cylinders were investigated which are

restrained by a chain fastened to a house using brackets or hook screws. The restraint of these cylinders

during earthquakes is important as gas leaks or fires can be caused. Testing the safety of the securing

methods was conducted using a series of static tensile tests and impact loading tests. These results were

compared to past earthquake data to determine the safety of the fasteners in different house cladding

materials. For the materials that proved to be insufficient, a new method was designed, tested and

verified. A set of fasteners and preparation procedures has been recommended for each of the materials

tested to ensure the security of the cylinders during earthquakes. A finite element analysis has also been

completed to simulate the movement of the cylinders during common earthquakes.

3 Project Scope The following section provides information on the scope of the project and how it has changed throughout

the project.

Research the securing methods that are already in place to give a good indication of how

different installers are securing the cylinders. From here, the team was able to identify the most

common method and create tests to determine the strength of the restraints.

Research on the types of cladding materials that the cylinders were secured to, these include

o Brick

o Wood

o Concrete

o Fibre board

o Hardies board

o PVC weatherboard

o ColorSteel

o Poly-plaster

Design testing rigs that will test the tensile strength of the securing methods, for comparison

with forces derived from earthquakes. These tests will incorporate the materials that the

securing device can be anchored to.

Develop an experiment and test rig that will use the information gathered from the tensile to

test the overall system on an earthquake table.

Identify the failure modes of the system which may induce a change in design of the securing

system

Develop a standard securing process that is safe under earthquake loads, simple for the

installers and requires minimal maintenance.

Changes have been made to the scope; this was due to the long-term unavailability of the Civil Engineering

Department's shake table. The earliest feasible date for use is in 2018.

The changes to the scope are as follows:

An impact test has been implemented to approximate loads that would be generated by a shake

table. Impact testing allows for more extensive testing of different designs, multiple materials,

different sizes and types of fasteners. The repeatability of each test is vital, as each material needs

to be tested in the same conditions. The impact test will allow repeatability and give accurate

results pertaining to each material.

The shake table has been taken out of the scope as it is unavailable and using a third party shake

table is costly.

Provide a FEA simulation that will replicate the shake table testing and provide validation to the

impact testing. This is a good alternative for the shake table test as the forces of an earthquake

can still be applied and it will provide comprehensive data on the systems behaviour

Overall, the changes that have been made to the scope due to the unavailability of the earthquake shake

table will allow more extensive testing and overall a better understanding of how each securing system

will behave.

4 Achievements

4.1 Site Visits Members of the group went on site visits with the purpose of gathering information about gas cylinder installations and how the installers conduct them. After talking to the installers, there was found to be two major installation methods, being a hook screw and a bracket and chain method as shown in figure 1. The chain is meant to be fastened approximately a quarter from the top of the cylinder; however it was obvious from the site visits that this guideline was rarely followed.

Figure 1: Hook securing method (Left), Bracket securing method (Right)

The bracket and chain method was favoured in newer houses, with the hook screw method being used in older houses. There seemed to be an even split in the method of securing with roughly half of the houses

using each method. However, the hook method was being phased out of use. The site visits also allowed the group to observe and document the different materials in which the brackets/screws were anchored into. The various materials observed were brick, mortar, weatherboard, poly-plaster and concrete.

4.2 Earthquake Research There was research undertaken to gain insight into common earthquake loading situations. This was

important for selecting the forces for the tensile testing, impact testing and shake table simulation. In the

case of this project, the peak ground acceleration (PGA) of the earthquake is the most important

parameter to consider. The PGA is split into the horizontal and vertical components and the horizontal

will have the most effect on the LPG cylinder system. The earthquake will exert this ground acceleration

to the house, which pushes the cylinder and in turn will cause the cylinder to pull on the chain. It was

found that the Heathcote Valley Primary School (HVPS) station recorded the highest horizontal PGA in

New Zealand on the 22 February 2011. Using GeoNet earthquake data for the HVPS station, during this

quake, the maximum horizontal PGA as a single vector was 12278 mm/s2. This is equivalent to 1.25 g. It

was decided that 1.2 g would be a suitable PGA selection to test to. This quake also recorded ground

velocities of up to 1.15 m/s. The velocity would be transformed into a maximum force that the chain and

bracket system should be able to withstand.

4.3 Earthquake Calculations After research and site visits were carried out, two different situations of the cylinder restraint

loading were decided upon. The first situation was when the cylinders were sitting flush against

the wall and restrained with a tight chain and brackets. The force exerted on the restraint system

in this situation would be a simple static load calculated by the following equation where F is the

force exerted on the restraints, M is the mass of the cylinders and, a is the peak ground

acceleration in the earthquake.

𝐹𝑟𝑒𝑠𝑡𝑟𝑎𝑖𝑛𝑡 = 𝑀𝑐𝑦𝑙𝑖𝑛𝑑𝑒𝑟𝑠 × 𝑎𝑒𝑎𝑟𝑡ℎ𝑞𝑢𝑎𝑘𝑒 𝐹𝑟𝑒𝑠𝑡𝑟𝑎𝑖𝑛𝑡 = 80 𝑘𝑔 × 1.25 × 9.81

𝐹𝑟𝑒𝑠𝑡𝑟𝑎𝑖𝑛𝑡 = 0.981 𝑘𝑁

The second loading situation involved the cylinders sitting flush against a wall restrained with a

chain and brackets. However, the chain was hanging loose. In an earthquake, this allows the

cylinders to tip a certain distance before the chain restrains them. As the cylinders tip, after the

earthquake has imparted a velocity to them, they gain velocity. Therefore, when the cylinders hit

the chain, the force exerted on the chain and brackets involves a velocity and is thus a dynamic

impact force. The impact force was calculated using impact factors, for a horizontal impact, in

the following equation.

𝐹𝑖𝑚𝑝𝑎𝑐𝑡 = 𝑊√2𝑣

𝑔∆𝑠𝑡

In this equation, W is the weight of the cylinders, v is the peak ground velocity applied to the

cylinders and g is the acceleration due to gravity. The variable ∆st is the theoretical deflection of

the system as if the weight force of the cylinders was applied statically to the restraints.

4.4 Testing Rigs Testing rigs were designed; these testing rigs needed to be able to take the full loads applied to them and

not deflect. The two tests rigs in figure 2 below are the designs for the impact and the tensile testing. A

more detailed description of the test rigs can be seen in appendix B. In addition, the finite element analysis

and the design description of the two rigs can be seen in appendix B

Figure 2: MTS testing Rig (left), Impact testing rig (Right)

4.5 Energy Calculations The ∆𝑠𝑡 of the chain was found by doing a simple tensile test in the MTS machine. The spring constant of

the chain was calculated from the Force vs Extension graph obtained from the test. After more research

into materials had been carried out, it was found that the ∆𝑠𝑡 of the materials and fasteners would be

hard to calculate. The reason for this was that the extension of the material under load could not be

obtained experimentally like the chain test extension. Each material would flex by a different amount

under impact load and the fasteners pulling out of the material would add another extension that could

not be measured. In place of an impact force, the kinetic energy of impact was a more precise way of

quantifying the intensity of the impact. Calculations were carried out to estimate the kinetic energy of the

impact of the cylinders with the chain in an earthquake. Simplifying assumptions were made to solve the

problem. The first assumption was that the full mass of the cylinders impacts the chain as the cylinder

tips. This assumption was conservative since most of the weight force would be acting through the ground

as the cylinder tips.

Figure 3: Modelled scenario of chain impact

The scenario, shown in figure 3 above, which was modelled, was that the wall, ground and cylinder are

initially travelling in one direction with the same velocity, the PGV of 0.98 m/s. The earthquake then

accelerates the wall and ground in the opposite direction at the PGA of 1.2 m/s2 and the cylinder

continues at 0.98 m/s in the original direction. This is another conservative assumption since the PGA and

PGV would not necessarily occur in that sequence in an earthquake. The cylinder tips and impacts the

chain. The velocity of impact is the difference between the cylinder’s velocity and the wall and ground

velocity. Another conservative assumption was that there was no force prohibiting the cylinder from

tipping. The cylinder would, in reality, be inherently stable and some velocity would be lost in overcoming

the weight force to tip the cylinder. The energy of impact is calculated from the kinetic energy of the

cylinders in the equation below. Where m is the mass of one cylinder and v is the relative velocity of the

cylinders and wall.

𝐾𝐸 = 1/2𝑚𝑣2

The energies of impact for different slack in chain are listed below in table 1

Table 1: Kinetic Energy at impact for different chain slacks

Length of

Chain Slack

(mm)

Final Velocity of Wall and Ground in

the same direction as Cylinder (m/s)

Difference in

Velocity of Cylinder

and Wall (m/s)

Kinetic Energy of

Cylinder wrt Wall &

Ground (J)

100 0.86 0.12 0.56

120 0.83 0.15 0.86

150 0.79 0.19 1.47

200 0.70 0.27 2.96

250 0.61 0.36 5.27

300 0.51 0.47 8.84

4.6 Chain Test The chain test was undertaken to prove that it would not be a method

of failure. Two plates were used with a hole drilled in one end of each

plate. A shackle was attached to each plate in order to allow the 5 links

of chain to be attached as seen in figure 4 below. A displacement load

of 100 mm/s was applied in the MTS machine to the chain until one of

the links broke. The number of links tested was five, with the middle

link breaking for two of the three tests, and the second from the

bottom breaking with the other test undertaken. From the chain test

data, the maximum failure load applied on the chain averages out to

9kN, this is well above the maximum load placed on the chain during

an earthquake of 0.94kN. With an elastic region of the chain below 6kN,

the chain will not deform as the load applied to the chain is well below

this value. The chain is therefore not a possible failure mode for the

system. Figure 4: Chain test set up MTS machine

4.7 Material Preparation

4.7.1 Material Research One of the most important aspects of the earthquake restraint of LPG cylinders is the house cladding.

Different types of cladding were investigated and local companies were consulted. Brick and

weatherboard were found to be the most common house claddings in New Zealand. Other less common

materials such as Palliside PVC weatherboard, ColorSteel, concrete block, Hardies board and plaster over

polystyrene were also acquired. In the case of each material, the thinnest sample was bought. Hardies

board was bought in 4.5 and 6 mm thicknesses. The minimum thickness of the Hardies board according

to the E2 External Moisture Building Code Section 9.7.1 (b) in Appendix M is 6 mm. The samples of plaster

over polystyrene were professionally prepared to the building code standard by Rockcote Plaster systems.

The preparation steps are listed in appendix P. All other materials were of standard thickness. Testing the

thinnest samples would therefore make the results conservative since the testing was done to a ‘worst

case’ scenario.

4.7.2 Sample Preparation Each material had to be prepared in a particular way to ensure that the strength of the bracket met the

loading criteria. These samples were intended to represent the existing fastener and backing

combinations. It was recognised that there would be variability in how each sample is prepared but this

gave another element in the testing, as each cladding would be prepared defiantly depending on the

installer. Each material was cut into 200x120 mm samples. The following indicates how the material was

prepared with the brackets for testing.

Brick - Two 6mm pilot holes were drilled into the centre of the brick. Once drilled, plastic rawl

plugs were inserted which provided a means for the bracket and screws to be fastened to.

Wood - The brackets were directly fastened with wood screws into the centre of the test pieces

Concrete - The concrete was prepared in the same fashion as the brick.

Hardies board - Two 6mm pilot holes were drilled. Once drilled plastic plugs which spread out at

the back were inserted. From here the bracket and screws were fastened to the material

PVC weatherboard - The bracket was directly screwed into the PVC weatherboard with no pilot

holes needed.

ColorSteel - Drilling of 6mm pilot holes, then the bracket was fastened with 6mm rivets

Poly-plaster - Two 6mm pilot holes were drilled then metal self-drilling plaster board anchors

were inserted. From here, the bracket was screwed into these anchors.

4.8 MTS Testing The jig was clamped into the MTS machine using pressure grip jaws, these kept the jig secure and ensured

it did not displace once the load was applied to it. The test specimen was clamped in the jig using nuts

and threaded rod attached to the jig, in order to keep the material stationary and secure. The chain was

attached to a shackle with five links of chain being engaged between the two jigs, this was then attached

to the bracket using the hook on the bracket. A level was used in order to ensure the material was

horizontal and the angle the chain was pulling at was vertical. This was to ensure consistency between

tests. A 10mm/s displacement load was applied until failure, with failure being classified as either the

fasteners pulling out or the bracket deforming so it would need replacing. The raw data was obtained

from the testing software and the maximum load taken from this data and plotted against other materials

in the below graph. An image of the MTS testing jig can be seen in figure 2.

Figure 5: Tensile Test Maximum Allowable Loads in each material

As can be seen from figure 5, the only material that did not pass the MTS testing is the 7mm white

polyplaster, as shown in red. This is while following the recommended fasteners using aluminum plugs

imbedded into the polyplaster. All other tested materials were found to have a maximum load above that

of the blue earthquake data, calculated to be 0.94kN. These are shown in green on the above graph.

4.9 L Bracket Performance One of the existing methods of cylinder restraint is the “L” shaped bracket shown below in figure

6. After testing the bracket in the MTS machine under a static load, it was determined that the

bracket was performing poorly. The position of the hook caused a moment about the first screw.

Essentially, this moment placed all the loading on one screw until it pulled out, then the other

screw was pulled out.

Figure 6: A failed L bracket showing the single screw loading

7mm Poly 99mm Poly Concrete Block Earthquake

Force

7mm Poly 7mm Poly Weatherboard Earthquake

Force

4.10 Alternate Securing Methods In the case of finding the current chain, securing method was not sufficient, there was to be a new

securing method proposed. The new system needed to be easily implemented on to the existing cylinder,

cost effective and be strong enough to withstand earthquake loading. The alternate solutions are shown

in Appendix C. From these alternative solutions, the T bracket was chosen for further analysis. The reason

for this was because of its simple design, the low cost to manufacture and how it distributes the load

equally between the screws. The Finite element analysis in Section 4.11 will provide a better comparison

between the brackets.

4.11 FEA of T and L Brackets To have a visual representation of the performance of the T and L brackets under loading, a finite element

analysis was conducted. The finite element analysis (FEA) simulated the loading on each bracket and

determined the stress and deflections of each bracket.

The load applied to each bracket was a conservative 1000N or 100Kg. This load was determined from the

combination of the earthquake loading and the mass of the two cylinders. The model had an average

mesh size of 2 mm, which were all brick elements. The boundary conditions applied to each bracket saw

a fixed condition on the holes to simulate the screws and an upwards surfaces force applied at the hook.

Figure 7 below compares the L bracket and T bracket performed with a 1000N load applied upwards at

the hook.

Figure 7: Stress on L bracket(Left), Maximum stress of 1291 MPa at first screw hole, Stress on T bracket (Right), maximum stress of 576 MPa located at the hook

It can be seen that a high stress region has developed around the closes hole to the hook on the L bracket.

This region has a maximum stress of 1281 MPa. This stress is past the yield point and will cause the bracket

to plastically deform upwards. Figure 7 Also shows that most of the force is applied to the first screw hole

which causes the pull out of the material. The t bracket on the other hand out performed the L bracket. It

can be seen that the maximum stress is only 576 MPa. Even though this stress is higher than the yield

stress of 300 MPa and will plastically deform the bracket, the load distribution though the T bracket is

evenly spread over both screws. Having this distribution of force allows the T bracket to have a stronger

connection and requires more force to pull the screws out.

Figures 8 give a representation of how the two brackets will deform under the load. The figures had a

scale factor of 10 applied so the deflections could be seen. As seen the L bracket deforms around the first

screw which validates the moment induced by the load and the overloading of the first screw. The T

bracket can be seen to deform in the middle, this shows that the load is evenly distributed between the

two screws as the displacement is symmetrical. These deflections were validated via the real-life testing

which had similar results. More images of the FEA on the L and T bracket can be seen in Appendix A

Figure 8: Deformation of L bracket (Left), Deformation of T bracket (Right)

4.12 Impact Testing The impact testing was used to simulate the loads of an earthquake by simplifying it to one large impact.

The largest values of peak ground acceleration (PGA) and peak ground velocity (PGV) of the Feb 2011

Christchurch were used. These values were used to make a model which testing would be based off. The

energy of the impact when the cylinders hit the chain was calculated. This would later be compared to

the potential energy of each drop test. The procedure for the impact testing can be seen in appendix L

while the impact raw data can be seen in appendix H an I.

After a good set of results had been obtained for each material an average value for the kinetic energy of

failure was calculated from the equation below.

𝑃𝐸 = 𝑚𝑔ℎ => 𝐾𝐸 = 1/2𝑚𝑣2

The potential energy of the mass trolley was assumed to be fully converted into kinetic energy when

impact happened, and that the connection between the rollers and the frame was frictionless.

The values of impact energy were shown in figure 9 below. Failure energies for the hook bracket and the

T bracket were also compared to the modelled earthquake energies.

Figure 9: Kinetic energy of impact compared to earthquake energies of impact for different slack in chain

As can be seen in the above graph, the strong materials are well above the 300 mm of slack in the chain.

This 300 mm of slack is a conservative value because in the site visits research, most chains had slack to

50mm. All the certified cladding materials were strong enough to withstand an impact from 200 mm of

chain. The poor performance of the 4.5 mm Hardies board was ignored since it is not a valid cladding

thickness and was only included for completeness. In the 6 mm Hardies board, the T bracket outperforms

the L bracket by a factor of 3. This result is due to the unequal loading of the screws in the L bracket.

While the T bracket was stronger in the thinner materials such as Hardies board and plaster, the L bracket

was equally as strong and sometimes stronger in the thicker, stronger materials such as brick,

weatherboard and concrete block. In the thinner materials, the screws would pull out before the bracket

could deform and thus the L bracket pulled out easily. The T bracket loaded both screws at the same time

and was therefore stronger. In the thicker materials, the screws stayed embedded in the material longer

because more thread was engaged. Thus, in the case of the L bracket, the bracket deformed before the

screws could pull out. The deformation of the bracket increased the time that the impact force was

applied. Since impact force is inversely proportional to length of time of impact, the magnitude of the

impact force was decreased. This relationship is shown below

𝐹𝑖𝑚𝑝𝑎𝑐𝑡 =𝑚𝑎𝑠𝑠 × 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦

∆𝑡

This allowed the L bracket to withstand larger drop tests in some cases. While this result showed that the

L bracket is safe in an earthquake, it shows that if some part of the system could be designed to be

“sacrificial”, the restraint system would be made much stronger. If one part of the system was designed

to fail in order to increase the time of impact, the system would be able to withstand much higher impact

loads. A spring attached in between two chain links would be highly effective at decreasing the impact

force caused by an earthquake.

The measured acceleration at impact was not used. Initially, an impact force was to be calculated by using

the mass of the trolley and the acceleration at impact. However, this relied on the assumption that the

acceleration was proportional to drop height. After numerous tests, it was discovered that for any drop

height that did not damage the fasteners, material or brackets, the acceleration was proportional to drop

height. Once the fasteners, brackets and material started to fail, this assumption was invalid. The reason

for this was the deformation of the system. If the system deformed, the impact would be carried out over

a longer time period. Since the accelerometer was measuring the deceleration of the trolley, the

deceleration was related to the time taken to slow the velocity of the trolley to zero. The measured

acceleration was thus affected and the reading was deemed to be inaccurate. Thus, the acceleration, while

being an indicator of impact force for smaller drop heights, could not be used for the drop heights which

induced failure

4.13 Recommended Fasteners After analysing the static and impact data, a set of fasteners have been recommended for each of the

materials that were tested. Throughout the testing the fasteners that were used were the most commonly

used by gas installers. For some materials a range of different fastener combinations were used and the

strongest was predicted. The following sections show the recommended fasteners for the materials and

a brief explanation on how to prepare the fasteners

4.13.1 Brick

Plastic rawl plugs with 4 mm wood screws or the 'L' bracket

screws.

Plugs and screws can be purchased from any hardware

store

Procedure involves pre-drilling holes for plugs

4.13.2 Timber Weatherboard

Any 4 mm woodscrews, 'L' bracket screws or Tek screws

No pre-drilling needed

Figure 10: Fasteners used in Brick

Figure 11: Fasteners used for Weather board

4.13.3 Palliside (PVC Weatherboard)

Any 4 mm woodscrews or the 'L' bracket screws

No pre-drilling needed

4.13.4 ColorSteel

5 mm aluminium or stainless steel pop rivet

Requires pre-drilling a 5 mm hole and the use of a pop rivet

gun

4.13.5 Concrete Block

Plastic rawl plugs with 4 mm wood screws

Pre-drilling hole for the size of the plugs

4.13.6 Hardies Board 6 mm

Plastic Cobra 054DE plugs were proved to be strong enough. Not just the screw alone.

Other plastic or metal plugs of similar shape and design can be used with caution

Involves pre-drilling a 6 mm hole

Figure 15: Anchors used in 6mm Hardies board (Left), Bracket and fasteners used (Right)

Figure 12: Fasteners and bracket used for Palliside

Figure 13: Fasteners and bracket used for ColorSteel

Figure 14: Fasteners, anchors and bracket used in Concrete Blocks

4.13.7 Poly-Plaster 9 mm thick

Metal self-drilling plasterboard anchors with 4 mm screws

Can pre-drill or self-drill with the anchor

Figure 16: Anchors used in 9mm PolyPlaster (Left), Fasteners and bracket used (Right)

4.14 Shake Table Plan From the beginning of the project a shake table test was planned. Campus construction has kept the shake

tables out of service for some time creating a large backlog. It is currently estimated that they will be

unavailable until early 2019. This test would be the most accurate representation of how an actual

earthquake effects the brackets on the different house claddings. Figure 17 show how the existing test rig

material holding plates were to be welded to the cross member to hold the test material samples. These

are shown in yellow and blue. The LPG cylinders were to be placed on the ground and fastened by the

chain. The test rig has holes in the legs of the frame that would be bolted to the shake table.

Figure 17: Modified impact rig (left), close up of modified point (Right)

The problem with the testing involved in this project is the large number of variables that can be changed.

This includes the 8 different test materials and the associated fasteners for each. This becomes a problem

when doing shake table testing as time using the tables is scarce. The advantage to the impact testing is

the ease of repeatability of tests and the large number of variables that can be easily tested. The shake

table would only have been valuable to validate data with only a small number of tests being able to be

conducted.

4.15 Earthquake Simulation A finite element model was developed to create a virtual shake table. This virtual testing would provide

comprehensive information on the forces applied by the earthquake to the cylinders, the force the

cylinders exert on to the securing system and will give an indication on the stability of the cylinders.

The setup of the simulation can be seen in figure 18. The main points to take out of the setup is the floor

and wall act as rigid bodies, this was to ensure that the force from the earthquake was exerted onto the

cylinders. Contact conditions were placed on the cylinders to allow for accurate contact mechanics. These

contact points included the interaction between the cylinder, the cylinders to the wall and the cylinders

to the strap. Special interactions were place on the strap to the wall and the cylinders to the floor. The

strap to the wall was a tie constrained which essentially connected the strap to the wall and did not allow

it to move. The interaction between the cylinders and the floor had a frictional coefficient applied to have

an accurate model to the real-life system. The results of this simulation can be seen in Appendix Q.

Figure 18: Set up of virtual shake table system

5 Schedule To date the following tasks have been added to the Gantt chart:

Tasks added due to change of scope:

Comprehensive Tensile testing

Comprehensive Impact testing

FEA Analysis on impact force of cylinder hitting chain (Simulation)

The addition of the last three tasks was due to the change in scope of the project. Instead of doing a full

system test on an earthquake table, the testing was altered to tensile testing, impact testing and a full

virtual simulation to validate this data.

The FEA virtual simulation of the cylinders has been added. This was to give a better representation of

how an earthquake will affect the cylinders.

So far in the project all of the original milestones have been completed in the correct time frame. This was

achieved by excellent planning from the team and the allocation of tasks to each team member.

Team:

Month

Date of Week Start 20th 27th 6th 13th 20th 27th 3rd 10th 17th 24th 1st 8th 15th 22nd 29th 5th 12th 19th 26th 3rd 10th 17th 24th 31st 7th 14th 21st 28th 4th 11th 18th 25th 2nd 9th 16th 23rd 30th 6th

Ref No. Description

i Project Selection

ii Team Organisition

iii Sponsor's Requirements

iv Project Planning

A-1 Preliminary Proposal

A-1 Final Proposal

1.0 Research

1.1 Earthquake research

1.2 Requirements & Specifications

1.3 Relevant standards

1.4 Site visits

1.5 Ultimate Loads on componenets

1.6 Calculations on shear strength of screws

1.7 Calculations of grip strength of securing material

1.6 Material research

M-1 Background information

A-2 Individual review 1

2.0 Conceptual Design

2.1 Updating proposal (Changes of testing method)

2.1 Requirerment and specifications of testing

2.1 Concept drawings of Testing methods

2.2 Concept of alternative secuing system

2.3 Detailed Design selection for tensil testing and impact testing

2.4 CAD model of both designs

2.5 Costing of materials

2.6 Detailed design of alternative method

2.7 Manufacturing Drawings

2.8 Therorectical calcuations

2.9 Preliminary testing of design

M-2 Design and experiment selection

A-3 Preliminary Report

A-3 Final Mid-Year Report

A-4 Mid-Year Presentation

3.0 Experiment set up

3.1 Producing drawings of test structure

3.2 Building test structure

3.4 Build alternative Securing prototype

M-3 Test structure Built

A-5 Individual review 2

4.0 Modelling & Experiment

4.1 Tensile testing

4.2 Impact testing

M-4 Modelling & Experiments Complete

5.0 Analysis

5.1 Analysis of Experimentail data

5.2 Checking the Validility of results

M-5 Concept Validated

6.0 Standard and process

6.1 Writing standard / process(Draft)

6.2 Review of draft

6.3 Final Standard produced

M-6 Standard or process Produced

7.0 Documentation

7.1 Technical drawings of Securing device

7.2

7.3 Computer Simulations

M-7 Documentation Complete

A-6 Individual Review 3

A-7 Poster draft

A-7 Poster

A-8 Presentation

A-9 Preliminary Team Final Report

A-9 Final Team Report

November

Weeks of Project Work

February March April May June July August September October

Exa

min

atio

ns

Lectu

re B

reak

Lectu

re B

reak

Lectu

re B

reak

6 Budget Type Cost Item Description Purchased From Rationale Quantity Budget Cost NZD

Goods Equipment

LPG Cylinder 45kg Cylinder Contact Gas Christchurch

Required to investigate bottle tipping and

forces required 1 Supplied

Chain and 'L' bracket sets

Chain that secures the bottles to the

buildings Aqualine Products Ltd- Darren Waith

Needed for the tensile and impact testing and

if shake table is used 20 Supplied

Materials

Mild steel hollow Section 100x50x6.0 mild steel 8m long Fletchers EasySteel Used for impact testing jig 1 193.28$

50x50x4.0 mild steel 8m long Fletchers EasySteel Used for impact testing jig 1 86.17$

Mild steel round bar 20mm 6m long Fletchers EasySteel For the impact test structure 1 38.22$

Threaded rod 12mm 2m length 8.8 grade Fletchers EasySteel Used for MTS and Impact jig 1 11.58$

Mild steel angle 20x20x3.0 6m length Fletchers EasySteel MTS jig 1 12.86$

Laser cut mild steel sheet 16mm plate AutoBend Christhurch

For the MTS jig and impact jig plates to hold

material 1 529.08$

Polystyrene sheets

2400 X 1200 X 40 S Grade Poly and 2401 X

1200 X 40 H Grade Poly Expol For poly-plaster sheet samples for testing 1 40.20$

D Shackles

8mm, 10mm, 13mm, 16mm D shackles. 2

of each Steel and Tube Christchurch For Impact and MTS testing. To hold the chain 8 40.30$

Drymix Plaster 10 kg Bag of Drymix plaster Mitre 10 Mega For making mortar samples 1 33.63$

Testing Fasteners

Rawl plugs, Tek screws, woodscrews,

plastic plaster anchors, aluminium

plaster anchors, hook screws Edward Gibbon Fastners for Testing 1 125.40$

Testing Fasteners

Dyna Bolts, Cobra wall plugs, plastic wall

anchors Mitre 10 Mega Fastners for Testing 1 64.25$

Nuts M12 University of Canterbury For MTS and impact jig 20 -$

M6 University of Canterbury For M6 bolts 10 -$

Washers M12 University of Canterbury For the M12 nuts on the threaded rod 20 -$

M6 University of Canterbury For M6 bolts 10 -$

Nylon rod NYLON 6 ROD 50mm dia LEP Engineering Plastics For rollers for the trolley 8 64.86$

U-bolts 8mm U bolts and Washers Steel and Tube For the weight trolley on the impact jig 16 50.97$

M6 X 15 NB U Bolts and M6 washers Mainland Fasteners For the weight trolley on the impact jig 16 48.21$

Pop Rivets Aluminium 5mm pop rivets University of Canterbury Colorsteel samples 20 -$

Freight - - - - 69.09$

Concrete Block Concrete Cinder Block Bunnings Warehouse Test Material 5 -$

Timber Weatherboard Weather board- 0.8m long Bunnings Warehouse Test Material 1 -$

Bricks Bricks donated from Canterbury bricks Canterbury Bricks Test Material 20 -$

Hardies Board 4.5mm thick and 6mm thick sheets Mitre 10 Mega Test Material 2 64.86$

Palliside uPVC weatherboard Palliside NZ Test Material 1 -$

Total Price 1,408.10$

Services Earthquake Table

Civil department earhtquake table next

year University of Canterbury

Used to test the bottles and chain assembly.

Need permission from Civil department -

Unknown Charge

from Civil

department

Site trips with Gas fitters Tim and Nic on visits

Too learn more about the current bottle

securing method and to gather photographs 5 Hours Covered by Contact

Garry Cotton Time

Building MTS jig and impact jig, also

shake table jig if needed University of Canterbury

Will need help with some of the fabricating

processes 80 hours 8000

MTS machine use Mechanical warehouse MTS machine University of Canterbury For tensile testing fasteners 20 hours 0

7 Implications The initial plan for this project was to build a test wall and utilise the UC Civil Department’s shake table to

test the restraining methods. Upon finding that the table was unavailable indefinitely, the team decided

to simplify the earthquake problem. The two situations which were decided upon were a static loading

case and a dynamic impact. The static loading case would account for the situations where the chain was

tight against the cylinders. Since from the site visits, it was seen that most chains were hanging relatively

loose, an impact test was locked in. This test would simulate the cylinders hitting the loose chain in an

earthquake. This outcome was fortuitous, since shake table tests are expensive and take a long time to

set up. The simpler tests are much more repeatable and quick to set up. As the building of the test rigs

commenced, problems were encountered with suppliers for materials such as U bolts, L brackets and

testing materials. These were minor setbacks and lost time was easily made up for.

8 Conclusions In place of expensive shake table testing a system of simple static and dynamic tests along with computer

modelling was successfully implemented to assess the adequacy of gas cylinderchain restraint systems for

resisting earthquake loading. Applying this system of testing and analysis it was found that gas cylinders

can be safely safely secured against the wall of a house under earthquake conditions for most standard

cladding materials. The cladding material that is unable to be securely fastened into is poly-plaster thinner

than 8 mm, this material will need to have a stud behind it in order to be fastened into. For every tested

material there was found to be a solution that allowed safe securing of cylinders. The recommended

fasteners for concrete block and brick were pre-drill a 6mm hole and use plastic rawl plugs with a 4mm

wood screw. For Palliside and weatherboard a standard 4mm woodscrew was used without any pre-

drilling required. ColorSteel required pre-drilling 5mm holes and pop riveting a 5mm rivet into the hole.

9mm poly-plaster required the use of a self-drilling plasterboard anchor in order to increase the surface

area and provide sufficient holding. Hardies board required the use of plastic cobra 054DE plugs, these

plugs required pre-drilling before installation and were designed to increase the surface area for the

fasteners to pull through. Although other similar plugs could be used with caution. A comparison between

impact data and chain slack can be seen in Figure 9 in the impact testing section of the achievements. The

T bracket was designed as an alternative to the existing L bracket and allowed the weaker materials such

as hardies board and 7mm poly-plaster to be securely fastened due to the load being more evenly

distributed over each fastener.

The simulation of the twin pack cylinders shows that they will not tip over in an earthquake situation. The

220kg cylinder will need to be restrained, not due to instability of the cylinder itself but due to the gas

lines attached to the top of the cylinder, as these will rip out of the wall if the cylinder becomes too far

displaced.

9 Future Issues and Limitations The future issues of the project going forward stem from the uptake of the set recommendations for gas

cylinder installers. If the recommendation is not made standard across the industry, then the testing may

prove to be invalid, this is especially true for weaker materials such as poly-plaster and Hardies board.

Another future issue is some existing installations are not up to the recommendation proposed by this

report, these will need to be reinstalled in order to maintain consistency with recommendations from the

project. Manufacturing the T brackets could be a future issue as there is not a current supplier which

stocks them. The weld in the bracket makes them more expensive to produce compared to the L bracket,

which can simply be bent into shape. Should there become a new material for cladding, then this would

need to be tested under the same circumstances as the existing materials in order to see if it can be safely

secured into.

10 Ethical Issues The future ethical issues can be seen in two areas, installers not following recommendations set in this

report and the communication of the changes and recommendations to the installers and gas changers.

The issues with the installers not following the recommendations set can affect the safety and stability of

the cylinders. It could put the home owner at risk with the cylinder falling over and leaking.

The issues created with a lack of communication can result in the incorrect securing method used for the

cylinders and also an incorrect chain height.

11 Contribution Statements Tim Stone – Tim has been involved in the materials research as well as the design and development of the

impact testing jig. Tim is the project manager of the group and is assigned to keep everyone on task and

the group running on schedule. In addition, he has taken on doing the CAD drawings for the group as he

has experience with it. He has also taken on all of the FEA analysis to do with the brackets and the virtual

cylinder simulation. He has been involved in all of the testing, where it be making components and

brackets or helping with the testing itself.

Nic Cammell – Nic has been involved in the materials research, along with the design and development

of the tensile test jig. Nic is the secretary and therefore has been in charge of taking the minutes during

the groups meetings. He has also been on site visits and has been involved in the research portion of the

project. He has been an integral part of the manufacture of the T brackets, along with the tensile and

impact testing. He has helped with the build of both of the tensile and impact test rigs. Nic was assigned

to complete the poster as part of the end of year presentations.

Dom Evans - The main task Dom carried out was all the calculations of earthquake force and energy and

their relationship to the impact tests. Dom was involved with organising materials for the impact and

static test rigs and preparing test specimens for testing. Dom also helped with the design and build of the

test rigs and the transported all cladding materials to the university. The first half of the impact testing

was carried out by Dom and Jack as well as mass trolley modifications. Dom held the meeting chair role

and resource manager role for a term each. Dom was also deeply involved with the earthquake research

and consulting academics for advice on analysis.

Jack Elliott- He was a part of the earthquake and material research stage. Jack was involved in designing

and constructing the tensile testing jig. Jack was the main person in charge of emailing the clients,

suppliers and supervisor. A lot of time was spent calling and emailing companies to organise getting all

the test material and material for both the test rigs. Jack accompanied Dom with going to the suppliers to

order and pick up materials needed for the building and testing. In addition, Jack was a large part of all

the impact testing along with organising how the testing would be done.

Dr. Mark Garnich gave technical advice and was group supervisor.

Distinguished Professor Geoffrey Chase, Dr. Geoffrey Rodgers and Greg Preston from UC Quake Centre gave advice on earthquake force calculations and data. Dr. Mark Jermy gave advice on shake table organisation and corresponded with the client. Dr. Paul Docherty gave advice on impact loading calculations and impact testing procedures. Garry Cotton gave technical advice and contributed fabrication suggestions in the workshop. Kevin Stobbs, Eric Cox, Paul Zwaan and Julian Phillips gave advice on data acquisition and testing. Mark Webb and Malcolm Oates from Resene Construction Systems prepared the polystyrene plaster samples. Greig Johnstone from GasCo selected the fasteners for the given materials.

12 References GeoNet. (2011). Christchurch mainstock. Retrieved from GeoNet:

ftp://ftp.geonet.org.nz/strong/processed/Proc/2011/02_Christchurch_mainshock_extended_pa

ss_band/Vol2/data%20in%20csv%20format/20110221_235142_HVSC_V2A.csv

Hardie, J. (2017). Products. Retrieved from James Hardie:

http://www.jameshardie.co.nz/?gclid=CjwKCAjwssvPBRBBEiwASFoVd0ICKP94krxpEKTPcLnUkhS

1Kah-gN1POGHpjR5uQXY0aY1bq2LkUhoCk2YQAvD_BwE

Massey, C. I., McSaveney, M. J., Heron, D., & Lukovic, B. (2011). Canterbury Earthquakes 2010/2011 Port

hills slope stability. Retrieved from CCC:

https://www.ccc.govt.nz/assets/Documents/Environment/Land/CR2011-311-01AUG2013.pdf

Mega, M. 1. (2017). Fasteners. Retrieved from Mitre 10:

https://www.mitre10.co.nz/shop/search?q=fasteners%3Arelevance%3Acategory%3A&category

Code=&text=fasteners

Palliside. (2017). Products. Retrieved from Palliside: https://www.palliside.co.nz/

Resene. (2017). Rockcote. Retrieved from Resene: https://reseneconstruction.co.nz/frontend/index.cfm

13 Recommendations to Client The recommended fasteners can be found in section 4.13 of the achievements for each of the tested

materials. The recommendation for the brackets is to be placed on the wall approximately 800mm apart

central to the two cylinders at a height of approximately 950mm from the ground. This allows the chain

to be tightly fastened three quarters of the way up the cylinders. The chain height is important, as this is

above the centre of mass acting through the cylinders in an earthquake situation. The most important

recommendation is that the chain has to be tight as this minimizes relative motion and impact loading

with the chain.

Stickers should be placed on the cylinders in order to make it clear to the installers where the chain must

be placed to provide safe securing.

The 220kg cylinder will need to be restrained in order to prevent the cylinder from pulling away from the

wall and rupturing gas lines.

14 Appendices

14.1 APPENDIX A (FEA Analysis on L and T brackets)

Figure 19: Stress in the T bracket, Maximum stress 576 MPa located on the inside of the hook

Figure 20: Close in view of the T bracket showing the stress on the hook, Max stress of 576 MPa

Figure 21: Deflection of the main boy of the T bracket. Symmetric around the mid plane

Figure 22: Side View of the deflection of the hook, as seen the hook deflects more than he body of the bracket

Figure 23: Stress in the X-X direction, Shows a compressive stress on the top of the hook of –375 MPa, and a tension stress of 434 MPA on the inside corners of the hook

Figure 24: Stress in the Y-Y direction, shoe the compressive and tension stress of –240 MPa and 506 MPa on the main hook upright.

Figure 25: Stress in the L bracket. High stress region around the first screw of 1291 MPa

Figure 26: Stress in the X-X direction gives a good indication of the compression and tension stress in the L bracket. Compression stress zones around the screw hole and on the hook.

Figure 27: Underside of L bracket with compressive stress around first screw hole of 484 MPa

Figure 28: Stress in the Y-Y direction. Indicates a tension and compressive stress in the main hook section of 603 MPa and –295 MPa respectively

14.2 Appendix B

14.2.1 MTS test Rig design To test the pull out strength of the range of fasteners a series of tensile tests were completed in a materials

testing system (MTS) tensile machine. The jig shown in figure 28. This was to hold the sample material

which includes Brick, Wood, Concrete, Fibre board, Hardies board, PVC weatherboard, ColorSteel, Poly-

plaster

Figure 29: MTS test rig

The whole jig is made of mild steel. The pieces of angle can slide in the notches to allow the test material

to be tightly secured. The top plate can be tightened down on the material with the M12 nuts. The jig

consists of laser cut 16mm mild steel plate at the top and bottom.

The material selected for the tensile test jig was 1020 mild steel. This provides a strong material as bending

must be kept to a minimum within the jig itself to allow for an accurate reading on the MTS machine. 1020

steel is also relatively cheap and so allows the budget of the project to be kept to a reasonable level. The

thickness of the chosen steel is 16mm, this effectively over engineers the jig to ensure rigidity and to

reduce error in measurements. Another advantage of 1020 steel is the high machinability and weldability

of the material, this allows the jig to be assembled and fabricated relatively easily using MIG welding along

with standard workshop tools. The rods for the supports and anchor point of the top and bottom jigs were

chosen to be 12mm threaded rod, this was chosen to allow an adjustable height for the bottom test jig in

order to fit the several different materials of different shapes and sizes.

14.2.2 Impact test rig Design The impact testing apparatus as seen in figure 30, is a simple drop tower design which utilises a large base

area of 850 mm x 1100 mm, to stay stable at impact. To reduce the effects of vibrations, a sand bag was

placed on the base. This is built out of 100x50 RHS, it was designed to stay rigid even when subjected to

large impulses and impact loads. The height of the rig is 1825 mm, this will allow the dropped mass to

reach high speeds of over four metres per second which is above the testing speeds. This ensures that

appropriate safety factors can be applied to the experiment without exceeding the maximum speed the

mass can reach, since velocity is dependent on height only. The mass was loaded on a trolley midway

between two guide rails. Four sets of nylon rollers keep the mass travelling straight downward. The nylon

rollers were chosen to reduce the effects of friction on the speed of the mass. The brick or concrete block

sat on a 16-mm plate with a cut out for attaching the fastening of the restraint. Another 16-mm plate

sandwiched the chosen material and kept it from moving after impact. 16-mm plate was chosen to stay

rigid during impact and improve the validity of the tests. The fastening bracket was screwed into the

material and a chain attached. The chain connected the mass trolley and fastening bracket.

Figure 30: Impact test rig

14.2.3 FEA simulation of Impact rig The boundary conditions used were:

Fixed constraints on the bottom surfaces on the base. This was to simulate that the test rig was

rigid and not going to move about its base.

A surface load of 6500 N was applied to the bottom plate of the material holder. This was to

simulate the impact load applied.

A mesh size of 12 mm was applied

These boundary conditions can be seen in figure 30.

Figure 31: Boundary conditions of impact test rig

The results of the testing revealed that the test structure would be able to withstand the testing

From this testing it can be determined that the impact testing rig will not fail under the maximum loading

condition.

The following are more images taken from the FEA.

Figure 33: Stresses in the impact testing rig

Figure 32: (left) shows the stresses that are induced in the structure with the applied load. The maximum load was 253 MPa which is below the yield point of the steel. This was located in the guide rails. (Right) The overall displacement of the structure. The maximum deflection of the structure is 4 mm this is seen in the main supporting branch; this amount of deflection in the main supporting arm will not have an effect on the experimental results.

Figure 34: Zoomed view of impact test rig

Figure 35: Displacement of impact test rig

Figure 36: Zoomed in view of impact test rig with max displacement of 4 mm

14.2.4 MTS Material holder FEA The boundary conditions that were used are:

Fixed constraints on the two surfaces where the MTS vice will hold the rig. This will simulate the

clamping of the jig and ensure a stable platform

The load was applied as a surface force on the top plate of the material holder. This gave an

accurate simulation of the actual force that will be applied to the jig.

A mesh size of 4 mm was applied

The boundary condition can be seen in figure 36.

Figure 37: Boundary conditions of MTS test rig

The results of the testing in figure 37, showed that the jig will withstand the ultimate force and will not

yield. The following figure shows the stress and the displacement of the jig

Figure 38: (Left) Shows the stress in the MTS material holder, the maximum stress is 156 MPa this is located in the threaded rod.

This maximum stress is under the yield stress. (Right) The maximum displacement of the jig is 0.5mm, this is located on the top

plate. This deflection will not have an influence on the experimental results.

The following images give more information about the FEA

Figure 39: Stress of MTS material holder jig

Figure 40: Max stresses in underside of MTS material holder jig of 156 MPa

Figure 41: Displacement of MTS material holder jig. Max displacement 0.5mm

14.3 Appendix C (Alternative Design)

Table 2: Alternative design table

DESIGN DESIGN DESCRIPTION PROS CONS

FABRIC STRAP WITH BUCKLE

A fabric strap made of polypropylene or could be nylon. A plastic or metal buckle will allow the strap to tighten around the cylinder

-Cheap option, mass producing the straps and buckles will allow them to retail for $1-$3 approx. -Tightening around the cylinder will stop it being able to wobble -Can easily adapt the current cylinder set up to have this method

-Could still have strength problems in the bracket fastenings -Slightly slower undoing time than the chain and hook

SHACKLE WITH SPRING

A metal shackle on a hinge with a spring. The spring allows the chain to stretch if the cylinder starts to tip which decreases the force exerted on the bracket screws

-Allows smaller brackets and fasteners to be used

-Price to produce will be high

LARGER DIAMETER SCREW

Basically, just use fasteners that can easily withstand the earthquake loads

-Can easily be implemented into the current method. Only involves replacement of existing screws

-More expensive than current method

EXTRA CHAIN AROUND HANDLE OF CYLINDER

Install another chain to go around the handle at the top of the cylinder. This will include brackets, screws and a hook like the existing method

-Will definitely eliminate the risk of the cylinder tipping -Easy to install -Not very expensive

-Will take longer for the gas workers to change over the cylinder

MOUNTED WALL BRACKET

Steel brackets screwed to the wall with a horizontal length of RHS or plate to stop the cylinder moving away from the wall

-Rigid design that would eliminate the cylinder tipping. However, the size screws would need to be calculated and tested

-Expensive to make -Would take some time to install -Would take the gas workers longer to swap the cylinders in and out

T BRACKET Steel bracket the same size as the L bracket except with the chain hook moved to the middle

-distributes the force equally over the two screws -easy change of design does not need any other equipment e.g. springs -cheap and easy alternative solution

-finding a manufacturer that will make the T bracket -welding the T brackets hook can add to cost of manufacturing

14.4 Appendix D (Fasteners)

14.4.1 Nylon plug technical data

Figure 42: Nylon plug technical data with ultimate pull out loads from website: http://www.welfastfastener.com/nylon_anchor.shtml

14.4.2 Appendix D (selection guide)

Figure 43: Fastener selection based on material. From steel and tube fasteners catalogue (Page 1 of 2)

Figure 44: Fastener selection based on material. From steel and tube fasteners catalogue (Page 2 of 2)

14.5 Appendix E (Material Data)

Figure 45: Strength and density graph of different materials

Figure 46: Yield and tensile strength table of different materials

14.6 Appendix F (Manufacturing drawings)

14.6.1 Impact testing

14.7 Appendix G (Tensile Testing Raw Data)

Table 3: Tensile Raw data of Timber Weather board

Rel Pullout Stength Tests/Variable

Timber Weatherboard 10 5Date of Test Name of Tester Max Load (kN) Load speed Comments Screw Type

Friday 28th July Jack, Dom, Tim, Kevin Stobbs 1.529 10 mm/min

Bracket twisted and bent downwards so chain slipped

off. Inside screw pulled out 2mm, outside screw did

not move 4mm Wood Screw 32mm long

4-Aug All 0.724 10mm/s bent hook screw hook screw



11-Aug All 1.08 10mm/s Bent hook screw round Tightened hook screw

- All 1.769 10mm/s Bent hook round Hook bent into V

- All 0.902 10mm/s Bent hook round Tightened hook screw

- All 2.02 10mm/s Bent hook round Hook bent into U

- All 2.042 10mm/s bent easy round Hook bent into U

- All 1 10mm/s

Loaded up to 1kN, bent bottom of bracket up off the

wood, the hook part didnt deform 4mm Wood Screw 32mm long

- All 2.595 10mm/s

New bracket, welded hook piece in the middle of

bracket 2.5mm steel. bent hook piece until chain

slipped off 4mm Wood Screw 32mm long

- All 1.935 10mm/s Hook bent round Hook into U

All 1.976 - - -

All 2.056 - - -

18-Aug Tim, Jack, Dom 4.557 10mm/s Bent bottom plate of bracket 4mm Wood Screw 32mm long

Table 4: Tensile testing raw data of Palliside

Table 5: Tensile testing raw data of Mortar

Table 6: Tensile testing raw data of Brick

Date of Test Name of Tester Max Load (kN) Load speed Comments Screw Type

Friday 28th July Dom, Jack, Tim, Kevin 0.827 10 mm/s Bent bracket a little 4mm Wood Screw 32mm long

11-Aug All 1.557 10mm/s New T bracket, didnt bend bracket 4mm Wood Screw 32mm long

11-Aug All 1.61 10 mm/s

T bracket with washers underneath to engage screw

thread. Pulled out easier than no washers 4mm Wood Screw 32mm long

11-Aug All 1.29 10mm/s 4mm Wood Screw 32mm long

11-Aug All 1.459 10 mm/s 4mm Wood Screw 32mm long

18-Aug Kevin, Jack, Dom, Tim 1.52 10mm/s Distorted the hook 4mm Wood Screw 32mm long

18-Aug Kevin, Jack, Dom, Tim 4.55 10mm/s Bend bottom plate a little 4mm Wood Screw 32mm long

18-Aug Kevin, Jack, Dom, Tim 1.911 10mm/s 4mm Wood Screw 32mm long



Palliside


4-Aug All 0.493 10mm/s ripped mortar straight out red rawl plug and 4mm woodscrew and bracket

4-Aug All 0.16 10mm/s red rawl plug and 4mm woodscrew and bracket

Mortar


4-Aug All 0.97 10mm/s Pulled plugs out easy

red rawl plug and 4mm woodscrew with hole

bracket

4-Aug All 0.72 10mm/s Bent hook screw, fastner stayed in Hook screw with red rawl plug

11-Aug All 0.7396 10mm/s Pulled out easily red rawl and 4mm woodscrew

18-Aug Tim, Dom, Jack, Kevin 1.54 10mm/s Didnt deform bracket red rawl and 4mm woodscrew

18-Aug Tim, Dom, Jack, Kevin 1.49 10mm/s red rawl and 4mm woodscrew

18-Aug Tim, Dom, Jack, Kevin 1.38 10mm/s bend backet a little red rawl and 4mm woodscrew


18-Aug Tim, Dom, Jack, Kevin 1.2 10mm/s bent hook a bit red rawl and 4mm woodscrew



18-Aug Tim, Dom, Jack, Kevin 1.56 10mm/s Used same holes red rawl and 4mm woodscrew

18-Aug Tim, Dom, Jack, Kevin 1.41 10mm/s Used same holes red rawl and 4mm woodscrew

Brick

Table 7: Tensile testing raw data of Concrete block

Table 8: Tensile testing raw data of PolyPlaster - Whit HD foam


Friday 18th August Kevin, Tim, Dom, Jack 1.605 10mm/s Distorted T bracket a little. Didnt bend base plate. red rawl plug with 4mm wood screw

Friday 18th August Kevin, Tim, Dom, Jack 1.6 10mm/s red rawl plug with 4mm wood screw

Friday 18th August Kevin, Tim, Dom, Jack 1.21 10mm/s Tbracket with start of hook milled at 2.5mm of centre red rawl plug with 4mm wood screw

Friday 18th August Kevin, Tim, Dom, Jack 1.8 10mm/s red rawl plug with 4mm wood screw

Concrete block


Friday 25th Aug Kevin, Dom 0.51 10mm/s

Pulled bracket to approx. 45 degrees and slowly pulled

1 screw out at a time. (white poly) White rawl plug with 4mm wood screw

Friday 25th Aug Kevin, Dom 0.73 10mm/s white poly 5



Friday 25th Aug Kevin, Dom 1.43 10mm/s Black poly 5

Friday 25th Aug Kevin, Dom 1 10mm/s Black poly 5











Poly Plaster- White HD foam

14.8 Appendix H (Impact testing, T bracket Raw Data) Table 9: Impact testing raw data of T bracket in ColorSteel

Material Date of Test

Material

Preparation Testers Observations

Mass of Trolley

(kg)

Top Height

(mm)

Bottom Height

(mm)

Change in

Height (mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration

(g)

Measured

Force (kN)

ColorsteelFriday 1st

September

5mm black rivets,

T bracket, flat

steel Dom, Jack Ripped out fully 7.55 219 905 686 26 3.668694591

ColorsteelThursday 7th

September

NEW SAMPLE

5mm black rivets,

T bracket, flat

steel Dom, Jack

No visible

damage 7.938 662 713 51 20 1.000309952 11 0.85658958


September Same Sample Dom, Jack

rivets fine, steel

bending in

middle 7.938 639 714 75 20 1.213053997 17.4 1.354968972



steel bent to

3mm see photo 7.938 616 716 100 20 1.400714104 19 1.47956382


September

NEW SAMPLE

5mm black rivets,

T bracket, flat

steel Dom, Jack

steel bent to

4mm see photo 7.938 590 715 125 20 1.566045976 22 1.71317916


September

NEW SAMPLE

5mm black rivets,

T bracket, flat

steel Dom, Jack Bent badly 7.938 516 716 200 20 1.980908882 23.5 1.82998683


September

NEW SAMPLE

5mm black rivets,

T bracket, flat

steel Dom, Jack Bent badly 7.938 465 715 250 20 2.214723459 26.2 2.040240636

Colorsteel

Table 10: Impact testing raw data of T bracket in Hardies board - 6mm


Material


Mass of Trolley

(kg)

Top Height

(mm)

Bottom Height

(mm)

Change in

Height (mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration

(g)

Measured

Force (kN)

HardiesBoardFriday 1st

September

5mm black rivets,

T bracket, flat

steel Dom, Jack Ripped out fully 7.92 602 710 108 20 1.455664797

HardiesBoardWednesday 4th

September

New Sample,

32mm wood

screws Dom, Jack

One screw out

completely, other

7mm 7.938 667 716 49 20 0.980499873 11.5 0.89552547


September

New Sample,

32mm wood

screws Dom, Jack Ripped out fully 7.938 665 715 50 20 0.990454441 10.9 0.848802402


September

New Sample,

32mm wood

screws Dom, Jack Ripped out fully 7.938 668 717 49 20 0.980499873 0


September

New Sample,

25mm wood

screws Dom, Jack

dropped 8mm &

3mm 7.938 665 715 50 20 0.990454441 11.1 0.864376758


September

New Sample,

25mm wood

screws Dom, Jack

dropped 8mm &

3mm 7.938 662 711 49 20 0.980499873 10.8 0.841015224


September

New Sample,

25mm wood

screws Dom, Jack Ripped out fully 7.938 659 709 50 20 0.990454441 10 0.7787178

HardiesBoardFriday 29th

September

Clear plastic

plugs Tim, Nic Nothing 7.938 671 716 45 20 0.939627586 13.2 1.027907496


September

Clear Plastic

Plugs Tim, Nic

dropped 4mm

and 0mm 7.938 645 715 70 20 1.171921499 19.7 1.534074066

HardiesBoard - 6mm

Table 11: Impact testing raw data of T bracket in Brick

Table 12: Impact testing raw data of T bracket in 4.5mm Hardies board


Material


Mass of Trolley

(kg)

Top Height

(mm)

Bottom Height

(mm)

Change in

Height (mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration

(g)

Measured

Force (kN)

Brick1Wednesday 4th

September

New Sample Red

Rawl Plugs Dom, Jack

dropped 2mm &

2mm 7.938 630 679 49 20 0.980499873 13.8 1.074630564

Brick2Wednesday 4th

September

New Sample Red


dropped 2mm &

1mm 7.938 608 685 77 20 1.229121638 20.7 1.611945846

Brick3Wednesday 4th

September

New Sample Red


dropped 5mm &

2mm 7.938 614 713 99 20 1.393692936 19.9 1.549648422

Brick4Wednesday 4th

September

New Sample Red


pulled out fully,

cracked brick in

half 7.938 589 714 125 20 1.566045976 28.9 2.250494442

Brick5Wednesday 4th

September

New Sample Red


dropped 5mm &

5mm 7.938 601 715 114 20 1.495553409 26.3 2.048027814

Brick8Wednesday 4th

September

New Sample Red


dropped 5mm &

5mm 7.938 594 713 119 20 1.527998691 27.9 2.172622662

Brick9Wednesday 4th

September

New Sample

Gray Rawl Plugs Dom, Jack

Cracked brick in

half but no drop 7.938 588 713 125 20 1.566045976 38 2.95912764

Brick


Material


Mass of Trolley

(kg)

Top Height

(mm)

Bottom Height

(mm)

Change in

Height (mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration

(g)

Measured

Force (kN)


September

25 mm screws t

bracket Dom, Jack Ripped out fully 7.938 682 712 30 20 0.767202711 7.5 0.58403835


September

25 mm screws t

bracket Dom, Jack

dropped 8mm &

3mm (failure) 7.938 693 714 21 20 0.641887841 21.3 1.658668914


September

25 mm screws t

bracket Dom, Jack

dropped 9mm &

3mm (failure) 7.938 693 714 21 20 0.641887841 6.3 0.490592214


September

25 mm screws t

bracket Dom, Jack

dropped 8mm &

3mm (failure) 7.938 694 714 20 20 0.626418391 6.4 0.498379392


September

25 mm screws t

bracket Dom, Jack

failed, then the

self weight of

trolley pulled out

fully 7.938 693 714 21 20 0.641887841 10 0.7787178

Hardiesboard 4.5mm

Table 13: Impact testing raw data of T bracket in Black Poly Plaster


Material


Mass of Trolley

(kg)

Top Height

(mm)

Bottom Height

(mm)

Change in

Height (mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration

(g)

Measured

Force (kN)

Poly-Plaster BThursday 7th

September

NEW SAMPLE

32mm screws,

Alu screw plugs

in black

polyplaster Dom, Jack

No visible

damage 7.938 665 714 49 20 0.980499873 17.9 1.393904862



No visible

damage 7.938 639 714 75 20 1.213053997 27.7 2.157048306



dropped 1mm,

hook on bracket

deformed a little 7.938 615 714 99 20 1.393692936 31.2 2.429599536



Pulled out fully

on one side

(failure) 7.938 590 715 125 20 1.566045976 28.8 2.242707264


September

NEW SAMPLE

32mm screws,

Alu screw plugs

in black

polyplaster Dom, Jack Pulled out fully 7.938 590 714 124 20 1.559769214 27.8 2.164835484


September

NEW SAMPLE

32mm screws,

Alu screw plugs

in black



September

NEW SAMPLE

32mm screws,

Alu screw plugs

in black

polyplaster Dom, Jack

Pulled out 7mm

and wrecked

plaster around it

(failure) 7.938 603 713 110 20 1.469081346 33.4 2.600917452


September

NEW SAMPLE

32mm screws,

Alu screw plugs

in black


Black Poly Plaster

Table 14: Impact testing raw data of T bracket in Palliside


Material


Mass of Trolley

(kg)

Top Height

(mm)

Bottom Height

(mm)

Change in

Height (mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration

(g)

Measured

Force (kN)

PallisideThursday 31st

August

Palliside with T

bracket and

wood screws Dom, Jack

Screws pulled out

evenly by approx

5 mm 7.55 545 690 145 16 1.6867 - -

PallisideThursday 31st

August

The same half

pulled out setup

(Continuation) Dom, Jack Ripped out fully 7.55 550 695 145 16 1.6867 - -

PallisideFriday 1st

September

Palliside with T

bracket and

wood screws (all

threaded) Dom, Jack

One screw pulled

out approx 10

mm. Other screw

unmoved 7.55 575 720 145 17 1.6867 - -

PallisideFriday 1st

September

The same half

pulled out setup

(Continuation) Dom, Jack Ripped out fully 7.55 580 722 142 17 1.6691 - -

PallisideMonday 3rd

September

Palliside, 2.5

Tbracket, thread

gap screws Dom, Jack No change 7.938 659 709 50 20 0.9905 7 0.54510246

PallisideMonday 3rd

September same Dom, Jack No change 7.938 645 710 65 20 1.1293 7.05 0.548996049

PallisideMonday 3rd


PallisideMonday 3rd

September same Dom, Jack

bracket pulled

out roughly 3mm

evenly 7.938 617 712 95 20 1.3652 7 0.54510246

PallisideMonday 3rd


PallisideMonday 3rd


bracket pulled

out another 2mm 7.938 600 712 112 20 1.4824 6.95 0.541208871

PallisideMonday 3rd

September same Dom, Jack Pulled out fully 7.938 578 715 137 20 1.6395 6.95 0.541208871

PallisideMonday 3rd

September

New sample

same as before Dom, Jack

pulled out by

1mm on one side 7.938 611 704 93 20 1.3508 7.85 0.611293473

PallisideMonday 3rd


both sides 2mm

out 7.938 572 681 109 20 1.4624 7.96 0.619859369

PallisideMonday 3rd

September

New Sample

same as before Dom, Jack

3.5 mm out each

side 7.938 535 685 150 20 1.7155 7.98 0.621416804

PallisideMonday 3rd

September

New Sample

same as before Dom, Jack Pulled out fully 7.938 524 683 159 20 1.7662 7.88 0.613629626

Palliside Dom, Jack Pulled out fully 7.938 525 685 160 20 1.7718 75 5.8403835




Palliside

14.9 Appendix I (Impact testing, L bracket Raw Data)

Table 15: Impact testing raw data for L bracket in Palliside

Reused

Sample

New

Sample No Fail

Borderline

failure

Full overkill

failure

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

Palliside1

Friday 22nd

September

Palliside with L

bracket and silver

screws Dom, Jack, Tim

bracket bent

from base 2 mm 7.938 645 709 64 20 1.120571283 13.6 4.98379392Palliside with L

bracket and silver


ripped out

(failure) 7.938 563 713 150 20 1.715517415 16.5 11.680767

Palliside2

Palliside with L

bracket and silver


bracket bent

from base 5 mm 7.938 599 709 110 20 1.469081346 - 8.5658958

Palliside3

Palliside with L

bracket and silver


bracket bent

from base 5mm 7.938 585 710 125 20 1.566045976 - 9.7339725

Palliside4

Palliside with L

bracket and silver


One screw out

fully other just

hanging on 7.938 555 710 155 20 1.743874996 - 12.0701259

Palliside5

Palliside with L

bracket and silver


bracket bent

from base 7mm 7.938 560 710 150 20 1.715517415 21 11.680767

Palliside6

Palliside with L

bracket and silver


One screw out

fully other just

hanging on 7.938 560 710 150 20 1.715517415 49 11.680767

Palliside7

Palliside with L

bracket and silver


One screw out

fully other just

hanging on 7.938 559 709 150 20 1.715517415 31 11.680767

Palliside

Table 16: Impact testing raw data for L bracket in Black Poly Plaster

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

Black Poly1

Friday 22nd

September

Black Poly with L

bracket and silver


One side fully out

(failure) 7.938 602 712 110 20 1.469081346 12 8.57

Black Poly2

Friday 22nd

September

Black Poly with L

bracket and silver


One side fully out

(failure) 7.938 613 712 99 20 1.393692936 17.4 7.71

Black Poly3

Friday 22nd

September

Black Poly with L

bracket and silver


One side fully out

(failure) 7.938 623 712 89 20 1.321431042 9.9 6.93

Black Poly4

Friday 22nd

September

Black Poly with L

bracket and silver


One side just

pulled out

(failure) 7.938 633 713 80 20 1.252836781 11.7 6.23

Black Poly5

Friday 22nd

September

Black Poly with L

bracket and silver


ripped out hit the

ground (failure) 7.938 633 713 80 20 1.252836781 15.7 6.23

Black Poly6

Friday 22nd

September

Black Poly with L

bracket and silver


One side fully out

(failure) 7.938 633 713 80 20 1.252836781 11.1 6.23

Black Poly Plaster

Table 17: Impact testing raw data for L bracket in 6mm Hardies board

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

6mmHardies1

Friday 22nd

September

6mm Hardies with

L bracket and

silver screws Dom, Jack, Tim

ripped out hit the

ground (failure) 7.938 661 711 50 20 0.990454441 11.3 3.89

6mmHardies2

Friday 22nd

September

6mm Hardies with

L bracket and


One side fully out

(failure) 7.938 691 711 20 20 0.626418391 5.6 1.56

6mmHardies3

Friday 22nd

September

6mm Hardies with

L bracket and


One side

dropped 3mm 7.938 697 709 12 20 0.485221599 6.2 0.93

6mmHardies4

Friday 22nd

September

6mm Hardies with

L bracket and


One side fully out

(failure) 7.938 694 709 15 20 0.54249424 6.1 1.17

6mmHardies5

Friday 22nd

September

6mm Hardies with

L bracket and


ripped out hit the

ground (failure) 7.938 698 710 12 20 0.485221599 6.3 0.93

6mmHardies6

Friday 22nd

September

6mm Hardies with

L bracket and


One side

dropped 3mm 7.938 698 710 12 20 0.485221599 4.3 0.93

6mm Hardies

Table 18: Impact testing raw data for L bracket in Brick

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

Brick1

Friday 22nd

September

Black Poly with L

bracket, Red

Rawls, silver


Bracket bent

away from base

5mm 7.938 609 709 100 20 1.400714104 26.2 7.79

Brick2

Friday 29th

September

Brick with L

bracket, red rawl

plugs, silver

screws

Dom, Jack, Tim,

Nic

Bracket bent

away from base

8mm 7.938 583 709 126 20 1.572297682 26.6 9.81

Brick3

Friday 29th

September

Brick with L

bracket, red rawl

plugs, silver

screws

Dom, Jack, Tim,

Nic

Bracket bent

away from base

11mm 7.938 583 709 126 20 1.572297682 18.2 9.81

Brick4

Friday 29th

September

Brick with L

bracket, red rawl

plugs, silver

screws

Dom, Jack, Tim,

Nic

Bracket bent

away from base

10mm 7.938 583 709 126 20 1.572297682 18.4 9.81

Brick Hook Screw

Friday 29th

September

Brick with Hook

Screw, Red rawl

plug Jack, Nic w 7.938 640 740 100 20 1.400714104 7.79

Brick

Table 19: Impact testing raw data for L bracket in ColorSteel

Table 20: Impact testing raw data for L bracket in 4.5mm Hardies board

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

Colorsteel 1

Friday 29th

September

Colorsteel with

Rivets

Dom, Jack, Tim,

Nic

Bracket bent

away from base

10mm 7.938 561 711 150 20 1.715517415 16.8 11.68

Colorsteel 2

Friday 29th

September

Colorsteel with

Rivets

Dom, Jack, Tim,

Nic

Bracket bent

away from base

14mm, one rivet

fully pulled out 7.938 561 711 150 20 1.715517415 34 11.68

Colorsteel 3

Friday 29th

September

Colorsteel with

Rivets

Dom, Jack, Tim,

Nic

Bracket bent

away from base

15mm, one rivet

fully pulled out 7.938 559 711 152 20 1.726916327 15 11.84

Colorsteel

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

4.5mmHardies1

Friday 6th

October

4.5mm Hardies

Board with clear

plugs Jack, Nic

Bracket bent

away from base

18mm on one

side 7.938 700 716 16 20 0.560285641 4.7 1.25

4.5mmHardies2

Friday 6th

October

4.5mm Hardies

Board with clear

plugs Jack, Nic

Bracket bent

away from base

18mm on one

side 7.938 700 716 16 20 0.560285641 4.8 1.25

4.5mm Hardies Board

Table 21: Impact testing raw data for L bracket in Weatherboard

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

Weatherboard 1

Friday 29th

September

Weatherboard

with wood screws

Dom, Jack, Tim,

Nic

Bracket bent

away from base

9mm 7.938 505 705 200 20 1.980908882 51 15.57

Weatherboard 2

Friday 29th

September

Weatherboard

with brass screws

Dom, Jack, Tim,

Nic

Bracket bent

away from base

28mm, one

screw pulled fully

out 7.938 107 707 600 20 3.431034829 35.5 46.72

Weatherboard 3

Friday 29th

September

Weatherboard

with brass screws

Dom, Jack, Tim,

Nic

Bracket bent

away from base

28mm, one

screw pulled fully

out 7.938 108 708 600 20 3.431034829 36.5 46.72

Weatherboard 4

Friday 29th

September

Weatherboard

with brass screws Dom, Jack, Nic

One Fastener

pulled out 30mm,

other fastener

hasnt moved,

hook is badly

bent 7.938 110 710 600 20 3.431034829 46.72

Weatherboard

Table 22: Impact testing raw data for L bracket in concrete block

Table 23: Impact testing raw data for L bracket in White PolyPlaster

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

Concrete 1

Friday 29th

September

Concrete Block

with red rawl

plugs Tim, Nic

Bracket bent

away from base

18mm, one plug

almost pulled out 7.938 510 710 200 20 1.980908882 35 15.57

Concrete 2

Friday 29th

September

Concrete Block

with red rawl

plugs Tim, Nic

Bracket bent

away from base

9mm 7.938 510 710 200 20 1.980908882 31.1 15.57

Concrete 3

Friday 29th

September

Concrete Block

with red rawl

plugs Tim, Nic

Bracket bent

away from base

17mm, one

bracket almost

pulled out 7.938 510 710 200 20 1.980908882 29.7 15.57

Concrete Block

Material Photo

number Date of Test

Material


Mass of

Trolley

(kg)

Top Height

(mm)

Bottom

Height

(mm)

Change in

Height

(mm)

Number of

chain links

Speed Before

Impact (m/s)

Measured

Acceleration (g)

Kinetic Energy at

impact (J)

White Polyplaster 1

Friday 6th

October

4.5mm Hardies

Board with clear

plugs Jack, Nic

Bracket bent

away from base

17mm on one

side 7.938 672 712 40 20 0.885889384 13.8 3.11

White Polyplaster 2

Friday 6th

October

4.5mm Hardies

Board with clear

plugs Jack, Nic

Bracket bent

away from base

18mm on one

side and almost

completely

pulled out 7.938 662 712 50 20 0.990454441 3.89

White Polyplaster 3

Friday 6th

October

4.5mm Hardies

Board with clear

plugs Jack, Nic

Bracket bent

away from base

18mm on one

side and almost

completely

pulled out 7.938 662 712 50 20 0.990454441 3.89

White Polyplaster

14.10 Appendix J (L bracket Loading Tables) Table 24: Force Table of Palliside

Impact Test

Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

64 1.120571283 21 1.63530738bracket bent from base 2

mm

150 1.715517415 49 3.81571722 ripped out (failure)

150 1.715517415 31 2.41402518bracket bent from base

7mm

150 1.715517415 21 1.63530738

One screw out fully

other just hanging on

(failure)

150 1.715517415 49 3.81571722

One screw out fully

other just hanging on

(failure)

Palliside

Table 25: Force Table of Black PolyPlaster

Table 26: Force Table of 6mm Hardies board

Impact TestDrop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

110 1.469081346 12 0.93446136One side fully out

(failure)

99 1.393692936 17.4 1.354968972One side fully out

(failure)


(failure)

80 1.252836781 11.7 0.911099826One side just pulled out

(failure)

80 1.252836781 15.7 1.222586946ripped out hit the ground

(failure)


(failure)

Black PolyPlaster



(failure)


(failure)

12 0.485221599 6.2 0.482805036 One side dropped 3mm


(failure)


(failure)

6mm Hardies

Table 27: Force Table of Brick

Table 28: Force Table of ColorSteel


100 1.400714104 26.2 2.040240636Bracket bent away from

base 5mm


base 8mm


base 11mm


base 10mm

Brick



base 10mm

150 1.715517415 34 2.64764052

Bracket bent away from

base 14mm, one rivet

fully pulled out

152 1.726916327 15 1.1680767


base 15mm, one rivet

fully pulled out

ColorSteel

Table 29: Force Table of Weather Board

Table 30: Force Table of Concrete Block


200 1.980908882 51 3.97146078Bracket bent away from

base 9mm

600 3.431034829 35.5 2.76444819


base 28mm, one screw

pulled fully out

600 3.431034829 36.5 2.84231997


base 28mm, one screw

pulled fully out

Weather board


200 1.980908882 35 2.7255123


base 18mm, one plug

almost pulled out


base 9mm

200 1.980908882 29.7 2.312791866


base 17mm, one bracket

almost pulled out

Concrete block

Table 31: Force Table of 4.5mm Hardies board

Table 32: Force Table of White PolyPlaster



base 18mm on one side



4.5mm Hardies Board




50 0.990454441 12.3 0.957822894



and almost completely

pulled out

50 0.990454441 14.8 1.152502344



and almost completely

pulled out

White PolyPlaster

14.11 Appendix K (T bracket Loading Tables) Table 33: Force Table of Black PolyPlaster

Table 34: Force Table of White PolyPlaster

Black Poly-Plaster (Alu plug 32mm Screws)Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

49 0.98 17.9 1.39 No visible damage

75 1.21 27.7 2.16 No visible damage

99 1.39 31.2 2.43

Dropped 1mm, hook

on bracket deformed

a little

110 1.47 33.4 2.60

Pulled out 7mm and

wrecked plaster

around it (failure)

111 1.48 23.8 1.85 Pulled out fully




Impact Test

White Poly-Plaster (Alu plug 32mm Screws)Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

49 0.98 14.5 1.13

pulled out 4mm and

5 mm (failure)

50 0.99 13 1.01

Pulled out fully on

one side (failure)

50 0.99 23.3 1.81

pulled out 3mm &

1mm (failure)

51 1.00 14.3 1.11

pulled out 4 and 5

mm (failure)

51 1.00 14.5 1.13

pulled out 5mm and

wrecked plaster

around (failure)

Impact Test

Table 35: Force Table of Brick

Table 36: Force Table of Hardies board 6mm

Brick (Red Rawl Plug 32mm Screws)Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

49 0.980499873 13.8 1.074630564

dropped 2mm &

2mm

77 1.229121638 20.7 1.611945846

dropped 2mm &

1mm

99 1.393692936 19.9 1.549648422

dropped 5mm &

2mm

114 1.495553409 26.3 2.048027814

dropped 5mm &

5mm (Failure)

119 1.527998691 27.9 2.172622662

dropped 5mm &

5mm (Failure)

125 1.566045976 28.9 2.250494442 pulled out fully

Impact Test

Hardies Board 6mm (32mm screws)Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

49 0.980499873 10.8 0.841015224

dropped 8mm &

3mm

49 0.980499873 11.5 0.89552547

One screw out

completely, other

50 0.990454441 10 0.7787178 Ripped out fully

50 0.990454441 10.9 0.848802402 Ripped out fully

50 0.990454441 11.1 0.864376758 Ripped out fully

Impact Test

Table 37: Force Table of Hardies board 4.5mm

Table 38: Force Table of Concrete Block

Hardies Board 4.5mm (32mm screws)Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

20 0.626418391 6.4 0.498379392

dropped 8mm &

3mm (failure)

21 0.641887841 6.3 0.490592214

dropped 9mm &

3mm (failure)

21 0.641887841 10 0.7787178

failed, then the self

weight of trolley

pulled out fully

30 0.767202711 7.5 0.58403835 Ripped out fully

Impact Test

Concrete Block (Red Rawl Plugs, 32mm screws)Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

125 1.566045976 55.5 4.32188379

dropped 3mm on one

side

150 1.715517415 42.6 3.317337828

dropped 3mm on one

side

150 1.715517415 53.9 4.197288942

dropped 3mm on one

side

150 1.715517415 47.5 3.69890955

No visible damage,

bracket bent well out

of shape

Impact Test

Table 39: Force Table of ColorSteel

Table 40: Force Table of Palliside

ColorSteel (5mm Pop Rivets)Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

51 1.000309952 11 0.85658958 No visible damage

75 1.213053997 17.4 1.354968972

rivets fine, steel

bending in middle

100 1.400714104 19 1.47956382

steel bent to 3mm

see photo

125 1.566045976 22 1.71317916

steel bent to 4mm

see photo

200 1.980908882 23.5 1.82998683 Bent Colorsteel badly

250 2.214723459 26.2 2.040240636 Bent Colorsteel badly

Impact Test

Palliside (32mm screws)Drop Height (mm) Velocity at Impact (m/s) Measured Acceleration (g's) Measured Force (kN) Comments on Failure

51 1.000309952 11 0.85658958 No visible damage

150 1.715517415 27.5 2.14147395

150 1.715517415 32.1 2.499684138

150 1.715517415 32.2 2.507471316

150 1.715517415 41.2 3.208317336

159 1.76623328 36 2.80338408

Impact Test

14.12 Appendix L (Impact testing Procedure) 1. A bracket or hook screw was fastened to the material to be tested with the correct

fasteners

2. The sample was loaded into the holder and locked in place with 4 bolts

3. A known length of chain was hooked onto the bracket. The chain was already fastened to

the mass trolley

4. The height of the top of the trolley was measured and recorded

5. The trolley was lifted to a height determined by the outcomes of previous tests

6. The potential energy was then automatically calculated from the mass of the trolley and

height it was lifted to

7. The trolley would then be released, would fall and impact the chain, bracket and fasteners

8. The acceleration at impact was measured with an accelerometer and recorded

9. If the bracket was deemed to be unable to withstand another small drop test, it was

classed as a borderline failure. (e.g. it was nearly pulled out of the sample)

10. If the bracket was fully removed, another test was carried out on a different sample at a

lower drop height. This would be repeated until failure was found.

11. Once failure was found, that drop height was repeated 2-5 more times until 3 borderline

failures were obtained from that drop height

14.13 Appendix M: E2 External Moisture Building Code, Section 9.7

14.14 Appendix N: Heathcote Valley Primary School Station Information

14.15 Appendix O: Heathcote Valley Primary School 2011 Earthquake Plots

14.16 Appendix P (Rockcote PolyPlaster preparation steps) The poly-plaster samples were prepared by Malcom Oates from Resene Construction Systems

Both the EPS & Graphex sheets have been Base Coated with Rockcote PM100 Quick Render Base Coat

between 4-5mm thick, RCS blue mesh was lightly trowelled into the surface and then straightened with

an Aluminium Darby.

The Base coat was left to cure for 24 hours approx. and then a 2nd coat of the Rockcote PM100 Quick

Render Base Coat was trowelled on and then floated to a smooth finish of up to 2mm thick, and left to

cure for another 24 hours approx.

Rockcote Fast Float Tasman was the textured finish, this is generally 1-2mm thick and finished with a

plastic float.

This was then left over the weekend and then primed/sealed with Resene Limelock, left to cure for

another 24 hours approx., when 2 coats of Resene's X200, was applied with a minimum of 2 hours

between coats.

14.17 Appendix Q (Earthquake simulation)

Setup

Twin Pack cylinder system Figure 47 shows the basic geometry of the system. It includes a rigid wall and floor with the twin pack

cylinders restrained against them. The boundary condition applied to the model consisted of a varying

displacement load, gravity and contact conditions between the cylinders, wall, floor and strap. The

cylinders seen in figure 47 do not have the same geometry as the real life cylinders but they have the

same properties and behave in the same way.

Figure 47: Virtual simulation set up

The Chain is simulated via a strap around the cylinders. This strap has the same material properties as the

chain. These properties were determined from the chain test that was conducted. Table 41 shows the

properties of the strap. Table 42 Shows the plastic strain zone which was used in the simulation to give

the strap an accurate behaviour once it has past the yield point, these values were determined off figure

48 Which shows the chain stress strain curve.

Table 41: Material properties of Chain

Properties Values

Elastic Modulus, E 20600 (MPa)

Density, ρ 7800 kg/mm

Yield Stress 450 (MPa)

Figure 48: Stress Strain curve of chain

From this stress strain curve the plastic strain could be determined via the following equation, these values

were entered in table !!! below:

𝜀𝑝𝑙𝑎𝑠𝑡𝑖𝑐 = 𝜀𝑡𝑟𝑢𝑒 − (𝜎

𝐸)

Table 42: Plastic strain data

Stress (MPa)

Plastic strain (mm/mm)

450 0

500 0.02

600 0.022

700 0.023

800 0.025

900 0.028

1000 0.03

1100 0.033

1200 0.037

-200

0

200

400

600

800

1000

1200

1400

1600

-0.01 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07

Stre

ss (

MP

a)

Strain (mm/mm)

Chain Stress Strain Curve

The displacement load applied, consisted of displacement data taken from the 6.3 magnitude

Christchurch earthquake. This data was obtained from the heath cote valley station from Geonet (Geonet,

2011). The displacement load consisted of 170 data entries with a time interval of 0.2 sections between

them. The displacement range was between -100mm to 230mm. The load was applied to the wall and the

floor; this simulated the movement of the earthquake and showed the behaviour of the cylinders. A

section of the displacement data can be seen in table 43.

Table 43: Heath cote valley displacement data

TIME

(SEC)

DISPLACMENT

(MM)

0 7.0

0.2 2.9

0.4 -1.5

0.6 -6.3

0.8 -11.5

1.0 -17.0

1.2 -22.8

1.4 -29.0

1.6 -35.5

1.8 -42.3

2.0 -49.4

2.2 -56.7

2.4 -64.3

2.6 -72.0

2.8 -80.4

3.0 -89.0

3.2 -97.6

3.4 -105.2

3.6 -107.8

3.8 -111.4

4.0 -101.9

The contact interactions are another important factor in the simulation, as it needed to be accurately

modelled to give accurate results. Most of the surface contacts were “Hard Contacts”, which allows the

system to hit surfaces and bounce off. The contact surface between the cylinders and the floor consisted

of a frictional coefficient to simulate the weight of the cylinder on the ground; this coefficient was 0.5,

which is the frictional coefficient between steel and concrete.

Chain slackness is another major variable in the simulation. This will be simulated via the gap between the

cylinder and the strap. The size of the gap varies between 0mm to 200mm. The simulation will consist of

a test at 0mm and 200mm slackness to show the difference in force and energies. The system geometry

can be seen in figure 49.

Figure 49: System geometry of the 200mm chain slack test

220kg Cylinder

This system was set up with the same conditions as stated above, except there is no strap securing the

cylinder to the wall. The cylinder again is not modelled exactly to the actual cylinder but it has the same

properties. This simulation is to determine the stability of the cylinder and to determine if the cylinder

needs to be restrained to the wall. The system geometry can be seen in figure 50.

Figure 50: System set up of the 220kg cylinder simulation

Assumptions The assumptions that needed to be made to this virtual simulation were as follows:

The mass of the cylinders consists of a full cylinder of 80kg

The geometry of the cylinders are simplified but have the same properties

The Earthquake displacement loads do not take into account the vertical displacement.

The wall and floors are rigid and do not absorb any energy form the cylinder hitting it.

The connection of the strap to the wall does not take into account energy absorption from the

bracket

Results

Twin pack System The results of the simulation can be seen in Figure 51 and in the simulation videos provided, This figure

indicates the max stress in the straps connection to the wall.

Figure 51: Max stress in strap connection to wall 100MPa

From the stresses, the force can be determined by the equation:

𝐹 = 𝜎𝐴

Where A = 250 mm2 and the stress taken from the model. In doing so figure 52 was constructed to give

an indication of the magnitude of the forces the strap would see. A red line on the graph is the testing

limit that was applied in the tensile and impact testing.

Figure 52: Earthquake force applied to strap from February 2011 6.3-magnitude earthquake

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

2.5

3

3.5

0 5 10 15 20 25 30 35 40

Forc

e (k

N)

Time (sec)

Earthquake Force on StrapEarthquake force onBracketTesting limit

From this graph, it shows that there are some forces applied from the earthquake above the testing limit.

Majority of the force applied to the strap was below this testing limit, which indicates that the bracket will

be able to with stand most of the earthquake’s force.

The strap tightness is another big part in the system; this can affect the forces that is applied to the

connection of the strap to the wall. The results from the 200mm strap slackness test can be seen in figure

53 and figure 54 below. Figure 53 shows the stress at impact on the strap. It can be seen that the stress is

higher than that of the tight chain test.

Figure 53: Cylinders point of impact and maximum stress of 503 MPa

Figure 54 below shows a comparison of the force from the tight strap to a 200mm chain slackness. It can

be seen from the graph that the forces on the system are considerably higher than that of the tight chain.

Figure 54: Force comparison of the slackness of the chain

220 kg cylinder The 220kg simulation results have shown that the cylinder will not tip over under these earthquake-

loading conditions. Figure 55 indicates the maximum tip angle the cylinder reaches. It can also be seen

that the cylinder has pulled away from the wall. Having the cylinder pull away from the wall may cause

the hoses to break and cause a gas leak.

Figure 55: Maximum tip of the 220kg cylinder. Cylinder has also pulled away from the wall

-10

-8

-6

-4

-2

0

2

4

6

8

10

0 5 10 15 20 25 30 35 40

Forc

e (k

N)

Time (sec)

Force induced due to Slack in Strap

0mm Chain Slack

200mm Chain Slack

Testing limit

This simulation has shown that the 220kg cylinder will need to be restrained to ensure that the cylinder

will not pull away from the wall and also not tip over. If a larger magnitude and more violent earthquake

was applied to the cylinder the cylinder might tip, so restraining it will prevent this from happening.

A suggested restraint of the 220kg cylinder will be to have the same chain and bracket as seen in the twin

pack, but only using one chain per 220kg cylinder.

Validation of testing results The data that was obtained from the simulation can be used to validate the impact testing. This can be

done by comparing the impact forces and the forces seen in the simulation. Comparing the results from

the raw data tables in appendix K it can be seen that the forces the impact testing applied to the test

pieces were similar to the force the earthquake applied to the chain in the simulation. The fact that the

forces quite similar indicated that the impact testing was an excellent alternative to the shake tables and

gave forces that simulated the earthquakes.

Conclusions It can be seen from the simulation that there is a great importance of how tight the chain must be to

withstand a large earthquake. From Figure 54 it can be seen that having a tight chain reduced the force

induced onto the brackets. This is due to the cylinder moving with the wall and not being able to gain

momentum to hit into the chain. In addition, the 220 kg cylinder will need a restraint around it as it is seen

to pull away from the wall and might cause a break in the gas lines.