657886_Shane Siy Cha_Final Logbook

E N V S 1 0 0 0 3 L O G B O O K SHANE DOMINIQUE SIY CHA

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[WEEK 01]

[MATERIALS]

BRICK “Brick is a masonry unit of clay, formed into a rectangular prism wh i l e p las t i c and hardened by firing in a kiln* or drying in the sun” (Ching 2008, 12.06) [More on Bricks in Ching 12.06] STEEL “Steel is used for light and heavy structural framing, as well as a wide range of building p roduc ts such as w i n d o w s , d o o r s , h a r d w a r e , a n d fas ten ings . ” As a structural material, it also combines high strength and stiffness with elasticity. (Ching 2008, 12.08) [More on Steel in Ching 12.08]

TIMBER4 Timber can be cut into different shapes and sizes, but is generally c u t i n t o d i f f e r e n t rectangular widths and lengths or may also be wedges shaped. It is commonly used as solid timber beams or r ec tangu la r beam sections.

•  See Glossary 1 http://1.bp.blogspot.com/-3AP40miqm6I/TxDBNPpaEOI/ AAAAAAAADCU/7ImozLVR8yg/s400/Brick.jpg 2 ht tp://www.meganracing.com/uploadimage/ dpage/1052010_171416.jpg

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•  STRENGTH: Is it strong or weak? (Ex. Steel is stronger than timber. It is also stronger in terms of compression and tension, while brick is only strong in compression)

•  STIFFNESS: Is it stiff, flexible, stretch? (Ex. Rubber is flexible, while steel is not)

•  SHAPE: Mono-dimensional (linear), bi-dimensional (planar; ex. Sheet metals), tri-dimensional (volumetric; ex. Brick)

•  BEHAVIOURS: Some are strong with compression (pushing together) or tension (pulling apart). Other materials will behave differently depending on where the force is applied.

•  ECONOMY AND SUSTAINABILITY: Is the material expensive? Readily available? What impact does the manufacturing of the material have on the environment?

[STRUCTURAL FORCES]

WHAT IS FORCE? •  A force is defined by direction, sense

and magnitude and is represented as a vector.

•  2 types of forces:

•  Tension Force

When an external load pulls on a structural member, the particles composing the material move apart and undergo tension. It stretches and elongate the material

•  Compression Force

When an external load pushed a structural member, the particles of the material compacts together. It shortens the material.

3 http://businessrecycling.com.au/images/masters/ image-974-timber-scraps.jpg 4 Unknown. (2013). Sawn Timber. Wood Solutions design and build. Retrieved from http://www.woodsolutions.com.au/Wood-Product-Categories/Sawn-Timber

[LOAD PATH EXAMPLE] LOAD PATHS The direction in which each consecutive load will pass through connected members (the beams) in which any load on the structural system is transferred into the foundations and distributed to the ground. A point load can be a dead load or a live load

•  Dead load5: permanent force acting on a structure

•  It is a constant load in a structure (as a bridge, building, or machine) that is due to the weight of the members, the supported structure, and permanent attachments or accessories

•  Live load6: can be moved, changing or non-permanent force acting on a structure

•  Ex. Force of the wind and the weight of things that are in or on a structure like the pressure of feet on stairs or the wind load (if outside) when going up the stairs.

•  The load to which a structure is subjected in addition to its own weight

5  Unknown. (2014). Dead Load. Merriam-Webster. Retrieved from http://www.merriam-webster.com/dictionary/dead%20load

6  Unknown. (2014). Dead Load. Merriam-Webster. Retrieved from http://www.merriam-webster.com/dictionary/live%20load

[STUDIO] Task: To build a tower as high as possible using MDF blocks

Our group considered square or triangular bases, however, we thought that the corners would be stress points within the structure. This would make the tower unstable and making it more likely to topple o v e r b e f o r e e v e n reaching the ceiling. The diameter of the tower we planned to build was estimated to be large enough to support the structure and still reach the

height that was required. In addition, it was not too small for the tower to buckle*. Also, we thought that having a diameter too wide would take us longer to create a taller tower.

We constructed the circular base layer with the bricks standing, while the second layer and the rest on top of it were “lying down” (as seen in the sketch). We thought that by constructing the tower with the bricks “lying down” would make it more stable, which would also maximize the material we had and the compressive and friction forces; meaning building higher with lesser blocks.

With the blocks arranged in that way, the load path in the structure would be travelling down as shown on the left.

Due to the time we had left, we changed our building pattern. Since the top layers of the structure has the least force compared t o t h e b a s e , w e changed our layers from just lying down to alternately standing and lying down. This is not as stable but it allowed us to build faster. Also, there is a

dec rease o f su r face con tac t t o compression ratio in the area contributing to friction forces.

DECONSTRUCTION

W e b e g a n deconstructing where the compress ion forces were greater, which meant the bottom of the tower. We k e p t p o k i n g holes for openings, making our way up by keeping it narrow and tall to keep the forces wi th in the s t r u c t u r e a s b a l a n c e d a s possible.

CONSTRUCTION

Because there was a change with the forces within the structure due to the opening that was made, the load path changed as well. The load of the removed blocks were then transferred to the other blocks that were left. The tower collapsed just when the opening reached almost mid-point.

MATERIAL – MDF BLOCKS

The blocks used for the tower were unreinforced. The dead load is creating compression within the structure. In addition, the friction* in this structure also lets each layer stay in place. The texture of the MDF block and the compression force that was created were enough to keep the structure up and at the right size.

MDF is high in density7 as well as its compressive (crushing) strength8 of 10MPa. This means that the material is actually able to carry a very large load. Although the blocks were unreinforced for this activity, these would not be efficient in real-life situations unless it’s reinforced.

OTHER GROUPS

•  This group built their tower the same way as ours e x c e p t t h e i r b a s e i s constant with the following layers

•  The top is more narrow, which will make it buckle less.

•  Similar to ours, there was good material efficiency with this group, especially the top part.

•  Only group to have an ellipse shaped tower.

•  Took longer to build due to the width

•  Not real ly material efficient

•  Less l ike ly to fa i l because it’s short and wide

•  Higher compression forces due to its mass

•  They used a different pattern (alternate the block standing and lying down)

•  Built their tower higher faster due to the pattern, but it wasn’t as strong as the others.

•  This decreased friction forces, which has more chances of buckling.

versus

•  See Glossary 7  Unkown. (2013). Retrieved from http://www.makeitfrom.com/

compare-mater ia ls/?A=Balsa&B=Medium-Densi ty-Fiberboard-MDF

8  IIbid.

[WEEK 02]

[STRUCTURAL JOINTS]

ROLLER JOINT

The load transfers only in one direction. It allows rotation, but resist translation in a direction perpendicular into or away from their faces (Ching 2008, 2.30). Like roller skates, they stay in place with a solely vertical load. Whenever lateral force is given, they roll in response. Roller joints are necessary for the ends of long bridges to compensate for the expansion and contraction of the bridges from temperature changes.

PIN JOINT

It allows rotation, but resists translation in any direction (Ching 2008, 2.30). There is no moment and resists both lateral and vertical forces. It is a mechanical joint that will transmit axial load* but will not transmit torque*.

FIXED JOINT

It is the most complex joint because bending* can occur. It maintains an angular relationship between the joined elements, restrain rotation and translation in any direction, and provide both force and moment resistance (Ching 2008, 2.30).

* See Glossary

[CONSTRUCTION SYSTEMS] ENCLOSURE/ENVELOPE SYSTEM

The enclosure system is the shell of the building (roof, exterior, walls, windows and doors) (Ching 2008, 2.03). This includes the resistance to air, water, heat, light and noise transfer, the aspects of the appearance, structure, safety, and security. The envelope system is the outer shell that maintains a dry, heated, or cooled interior and facilitate its climate control.

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1 https://www.energystar.gov/ia/new_homes/ next_generation/images/2011House_4ThermEnv_lg.jpg 2 http://www.bentley.com/NR/rdonlyres/ EB26643C-5C2F-4CB7- AA1F-7E05CF5ED6A3/28928/3d1.jpg

STRUCTURAL SYSTEM

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A structural system of a building is designed and constructed to support and transmit applied gravity and lateral loads safely to the ground without exceeding the allowable stressed in its members (Ching 2008, 2.03). Examples of structural systems would be columns, beams and load bearing walls that support the floor and roof structures.

SERVICE/MECHANICAL SYSTEM Provides essential services to a building such as water sewage, heat ing, ventilating, electrical, vertical transportation systems or lifts, fire-fighting systems and waste disposal.

KEEP IN MIND WHEN BUILDING…

Aesthetic Qualities – physical qualities of the building (Refer to Ching 2008, 2.04) Economic Efficiencies – needs to be affordable; the initial cost looks at whether it fits the budget and the life cycle cost looks at the longevity of the material. (Ching 2008, 2.04) Environmental Impacts – If the materials used are good for the environment or not. (Ching 2008, 2.04)

ENVIRONMENTALLY SUSTAINABLE DESIGN

Embodied Energy is the total energy (oil, water, power) used during a material’s life Life Cycle starts with extraction of raw materials from the Earth and ends with waste product disposal back to earth or is recycled into other products. Recyclability is potential for a product/material to be reused or transform into a new product Carbon footprint is the measure of the amount of GHGs generated during the fabrication, transportation and use of a particular product. Common ESD Strategies: Local Materials, thermal mass, solar energy, cross ventilation, insulation, material efficiency, night air purging, wind energy, smart sun design, water harvesting

Performance Requirements – for comfort and protection such as control of heat and air flow through the building assemblies, control of migration and condensation of water vapor, and noise reduction. (Refer to Ching 2008, 2.04 for more)

[STUDIO] Task: To build a tower as high as possible using balsa wood strips

We thought that if we kept the tower straight, the balsa wood would not be heavy enough to prevent any structural errors unlike last week with the MDF blocks. This could cause the tower to topple over easily. So we changed the design by tapering* the column to make sure that the mass of the bottom part would be greater than the top of the tower to stabilize it. To build a higher tower, we needed to make use of our materials more. So we altered the design again by removing one vertical strip at one side per triangle.

T h e d e a d l o a d i s transferred downwards while the crossbeams* work to lessen the effects of any tension. The base triangle was created by overlapping and super gluing the edges of the strips.

The triangle on top of the base was the same size as the base to create a little extra mass and increase compressive forces. Joints* were s t rengthened by overlapping the strips which were held by a pin (pin joint) and strengthened with super glue as a “fixed joint”. However, removing one vertical strip at one side per triangle led to unbalanced load transfer throughout the s t ruc ture wi th to rs ion* becoming evident. As we added more levels, the tower continued to twist, but remained upright.

The rotation most probably occurred because of the displaced load that should have been balanced by the balsa strip on the missing side. This cause unevenness at the apex* because the displaced load travelled there instead.

The sketch shows that i n s t e a d o f u s i n g longer balsa strips, we t r i ed to save material and used a smaller piece to hold the angle instead.

As the vertical load w a s a p p l i e d b y pushing the tower d o w n , t h e s t r i p s buckled where one end is fully restrained a n d t h e o t h e r swayed. When he force became too g r e a t , u n e q u a l distribution caused t h e s t r u c t u r e t o collapse.

MATERIAL – BALSA WOOD

Balsa wood has excellent stiffness-to-weight and strength-to-weight ratios.3 Under axial compression, the material exhibits elastic behaviour, which terminates by the initiation of failure in the form of localized kinking*.4 Our tower did not kink or snap under stress, but the joints of the structure failed. The members that snapped were most likely because of the way the strips were cut Overall, balsa wood is efficient in carrying dead load even under stress. Failure of the joints were only because of how we bui l t and put together the tower (interlocking and overlapping).

3 h t t p : / / w w w. m a k e i t f r o m . c o m / c o m p a r e - m a t e r i a l s / ?A=Balsa&B=Medium-Density-Fiberboard-MDF 4 h t t p : / / w w w. s c i e n c e d i r e c t . c o m / s c i e n c e / a r t i c l e / p i i /S0020768307002727

GROUP COMPARISON

Compared to our tower, this group on the left put 2 triangles on top of each other, while they kept their base just 1 triangle. The top part of their tower was stronger than the bottom when deconstruction was being done. The long members buckled and bent just like ours.

This group’s tower was too wide, which wasted their material and at the same time kept it short.

However, it also did not make it any more stable and it broke easily as force was applied. This was probably because there was no brace and the base was not strong enough to hold the whole thing with force. Another reason for the collapse would be because of inefficient joining techniques.

This group’s tower was particularly interesting. It was a square based tower where the crossbeams distributed the load evenly. If only their base was stuck properly and stronger, the whole thing could have been more diff icult to deconstruct. This structure had more stress or vertical force compared to others before collapsing, which happened near the base (at the joint). Because of the bracing, it made the tower bend under stress and flexed as well.

[WEEK 03]

[STRUCTURAL ELEMENTS]

BEAM A b e a m i s a horizontal element designed to carry v e r t i c a l l o a d s using its bending resistance. It is also used to

support a roof or a building. There is a tendency for a beam to bend and change shape, which is why there is an equal amount of compression and tension to keep it balanced.

PANEL A panel carries loads v e r t i c a l l y o r horizontally. Walls can carry loads to a footing o r s l a b . I t i s a component that is sent

into the surface, a wall, ceiling or door.

SHEAR DIAPHRAGM A shear diaphragm is like a panel. It prevents over turning. Walls can also act as a bracing system; without a shear

diaphragm, bracing consists of struts or ties.

TIE

Ties are slender element designs to carry loads parallel to its long axis. The load produces tension. It is a tension element and pulls apart. In addition, it is a rod or beam that hold parts of a structure together. An example would be cable ties.

STRUT

A strut is a rod or bar forming part of a framework and designed to resist compression. Basically, it is a slender element designed to carry loads parallel to its long axis like a tie, but produces compression. It can be an element within a truss. An example of a strut would be a column.

SLAB OR PLATE

A slab or plate is a w i d e h o r i z o n t a l element designed to carry vertical loads in bending. It is usually supported

by a beam and the load is transported across. A slab is a large, thick, flat piece of stone or concrete.

[CONSTRUCTION SYSTEM]

FOUNDATION AND FOOTINGS

The foundation is a substructure of a building constructed wholly or partly below in order to support the superstructure (Ching 2008, 3.02)

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1 http://static.concretenetwork.com/photo-gallery/images/300x200Max/site_26/concretenetwork-com_6179.jpg 2 http://www.clarkebasementsystems.com/core/images/foundation-repair/foundation-problems/settlement-sinking/settling-foundation-lg.jpg

Overtime, buildings compress the earth beneath them and they tend to sink a little. Soils expand when wet and shrink when dry, so footings and foundations should be designed to ensure that the bearing capacity of the soil is not exceeded. Otherwise, there may be movement in brickwork or dif ferent ial set t lement (cracking in a building).

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Shallow footings à used when soil conditions are stable. The load is transferred vertically from the foundation to the ground.

•  Friction piles: rely on the resistance of the surrounding earth to support the structure.

•  Pad Footing: (or isolated footings) help spread a point load over a wider area of ground (See Ching 3.08).

•  Strip Footing: u s e d w h e n loads from a wall or series of c o l u m n s i s spread in linear manner (Ching 3.08)

•  R a f t Foundation: (or r a f t s l a b ) p r o v i d e s i n c r e a s e d s t a b i l i t y b y joining the the individual strips together as a s i n g e m a t (Ching 3.08)

Source: Ching 2008, 3.09



Deep foundations à usually used when buildings are heavy and when soil conditions are unstable or soil cannot bear the capacity. The load is transferred from the foundations through the unsuitable soils down to the bed rock.

•  End bear ing p i les: ex tend the foundations down to rock or soil that will provide support for the building loads

Methods to construct piles: 1.  Driving long timber/steel/concrete

members into the ground 2.  Drilling into ground then filling hole with

concrete (cages of steel reinforcement are usually placed first before filling the holes)

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BASEMENT DESIGN Retaining and Foundation Walls: used when sites are excavated to create basements or where changes in site levels need to be considered to prevent the wall from overturning.

•  Piles and Piers: Can help support and carry the load of adjacent soil then they get in filled.

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3 & 4 http://www.globalsecurity.org/military/intro/images/pile-image1.gif 5 http://www.thrasherbasement.com/core/images/foundation-repair/foundation-repair-products/pier-system/push-piers/02lg-installed-push-piers-picture.jpg

1 http://www.logibrik.co.za/images/clay-stock-bricks.jpg 2 http://static.panoramio.com/photos/large/11435929.jpg 3 http://www.recoore.com/hardware/images/detailed/1/Concrete_Block-02137484473251f2773c06bdf.jpg 4 http://www.rockymountainstoneproducts.com/img/stoneP/Ashlar/Ashlar_Amber.jpg 5 http://thumbs.dreamstime.com/x/shovel-wet-concrete-5953835.jpg 6 http://www.chiangmailifeconstruction.com/wp-content/uploads/2010/07/DSC_0236.jpg 7 http://upload.wikimedia.org/wikipedia/commons/3/3c/Stonehenge2007_07_30.jpg

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Pyramid of Giza

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1 http://www.smileysmasonryinc.com/wp-content/uploads/2012/10/masonry_feature_image.jpg

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1 h t t p : / / w w w. b r i c k s - t i l e s . c o . u k / i m a g e s / p r o d u c t s / b r i c k s /KKJ-7088_36_max.jpg 2 http://jeninavarro.wikispaces.com/file/view/Selkirk-Pressed_big.jpg/342049710/Selkirk-Pressed_big.jpg 3 http://www.pittdixon.go-plus.net/jacksons-brickworks/handmade-brick.gif 4 http://www.homezonebuilding.com.au/ImageGen.ashx?image=/media/3726/jargon_perpend_copy.jpg&width=130&alt Image=/images/homezone_template/blank.png

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[WEEK 04]

[CONSTRUCTION SYSTEMS]

SPAN

•  D i s t a n c e m e a s u r e d b e t w e e n t w o s t r u c t u r a l supports

•  C a n b e m e a s u r e d between vertical suppor ts ( fo r h o r i z o n t a l members ) o r h o r i z o n t a l suppor ts ( fo r v e r t i c a l members)

•  Not necessarily same length as the member

SPACING

•  O f t e n associated with s u p p o r t i n g elements (ex. B e a m s , columns)

•  C a n b e m e a s u r e d h o r i z o n t a l l y /vertically

•  G e n e r a l l y m e a s u r e d center- l ine to center-line

àSPACING of the supporting elements depends on the SPANNING capabilities of the supported elements

FLOOR SYSTEMS •  Concrete

•  There are slabs that spans in 2 directions or shorter distances between supporting structure

•  See Ching 2008, 4.03 for more

•  Timber •  Some joists further apart, then

floorboard has to be stronger •  Consists of joist—supported by

bearers (primary beams)— which supports the flooring

•  Usually close to each other (span of bearers)


Source: http://www.tatasteelconstruction.com/file_source/Images/Construction/Reference/architectural%20studio/design/F0700001a.jpg

Source: ht tp://steelmax.com.au/f i les/uploads/2010/10/t imber-floor-450x297.gif

[STRUCTURAL SYSTEMS]

BEAMS

•  Mostly horizontal structural element •  Function: to carry loads along the

length of the beam & transfer loads to vertical supports

•  Can be supported at: •  Both ends of the beam •  Numerous points long the beam •  Points away from ends of the

beam = creates overhangs/cantilevers beyond the supports

•  Only one end of the beam = cantilevers

•  See Ching 2.14 for more

CANTILEVERS •  Created when a structural element is

supported at only one end or the overhanging portions of a member are significant

•  Function: Carry loads along the length of the member & transfer these loads to the support

•  Can be: •  Horizontal •  Vertical •  Angled


1 http://civilengineersforum.com/difference-between-one-way-slab-two-way-slab/ 2 ibid. 3 http://2.bp.blogspot.com/-xC-5zf5Sq30/TtpIRR1XxXI/A A A A A A A A A D w / d 1 S U V F a d W m w / s 1 6 0 0 /i_Beam_drawing_large.JPG 4 http://oceanocommunity.com/wp-content/uploads/2013/06/cantilever.jpg

SLABS à various types are used to span between structural supports. These can be:

•  Steel •  Open web trusses (lightweight

joist) are close to each other •  Joists are further apart (flooring

has to be stronger) •  Framing systems: take various

forms, with some utilizing heavy gauge structural steel members & others using light gauge steel framing.

•  Heavy weight joists spanning between girders

•  Most of the time combined with concrete slab systems for compression


One-way Slab Two-way Slab

Supported by beams in only 2 sides

Supported by beams in all 4 sides

Longer span panel : shorter span panel = or > 2

Longer span panel : shorter span panel < 2

Main reinforcement provided in only 1 direction

Main reinforcement provided in both directions

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One-way Slab: Two-way Slab:

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Source: Constructing Environments Subject Outline, 2014, p. 24 Source: Constructing Environments Subject Outline, 2014, p. 23 Source: Constructing Environments Subject Outline, 2014, p. 22

Source: Constructing Environments Subject Outline, 2014, p. 25 Source: Constructing Environments Subject Outline, 2014, p. 27 Source: Constructing Environments Subject Outline, 2014, p. 28

[CONSTRUCTING WORKSHOP]

Materials used: 2x plywood (1200 x 3.2 x 90 mm) 2x pinewood (1200 x 42 x 18 mm)

We first thought that since it has to span 1 meter and has to be able to carry a heavy load, then it would be better for our structure to be flat. This way it would take longer to break that if it was curved like a bridge since there is already compression at the bottom and tension at the top. This would also save us materials

We then decided to use the pine wood as our “base” because it was much thicker than the plywood. So we cut from both pinewood and nailed it to the sides until we created a span of 1 meter. This left us with a hole in the middle.

We then cut the plywood so we can nail it to the pinewood base to cover the hole in the middle. We first drilled the plywood at 2 ends instead of n a i l i n g t h e m directly because we figured that this would have less r isk w i th cracks on the plywood. Then we just continued on to cover the hole with every p l y w o o d w e had.

Once covered, we had extra materials so we doubled the plywood in middle to make the area where the load will be placed stronger.

DECONSTRUCTION

It took our group 60mm of deflection and 350 kg later for the structure to break. Doubling the plywood on the middle made the structure a little bit stronger. However, even if plywood is strong and the pinewood was pretty thick, it could only hold so much weight so at a certain amount of tension and compression, it had to break. The nails first popped and then the pinewood cracked. This was because the plywood part was still strong enough while the pinewood was not.

MATERIAL–PLYWOOD & PINE WOOD

PLYWOOD1: Plywood is made from layers of solid timber veneer, which makes it incredibly strong. Each new layer is rotated 90° to maximize the strength of the board and prevent from warping and twisting. Since each layer added was twisted, cutting the plywood apart reduced its strength for our structure.

PINE WOOD2: Pine is considered a soft wood, which could be a cause of why it was not strong enough to carry a heavier load other that the way the structure was made. Pine is also average with its compressive and bending strengths as well as its stiffness. This means it can carry a heavy load, but only to a certain point.

* See Glossary 1 http://www.woodworkbasics.com/plywood.html 2 h t t p : / /wo r kshopcompan ion .com/KnowHow/Des ign /Nature_of_Wood/3_Wood_Strength/3_Wood_Strength.htm

GROUP COMPARISON

•  Formed like a bridge •  Cut up pine wood, put them together

using plywood – not a good idea; reduces strength for plywood

•  Deconstructed quickly because the structure tried to tense even more.

•  Formed like a bridge but not curved •  Heavy “columns” at the sides, but it did

not have support at the middle—it was a very flat beam

•  The flatness of the beam made it deflect* a lot with the force acting on it

•  Deconstructed at 200 kg with 100mm deflection

•  Very very thick structure, but it was thinner at the sides; most probably because they lack materials

•  Used plywood to connect all the other wood

•  Because of the thickness, it took a very long time to deconstruct their structure

•  It was able to carry a heavy load •  As in created tension at the top and

compression at the bottom more, it finally started to crack a little at the bottom

•  Deconstructed at 620 kg with 20mm deflection

[WEEK 05]

[STRUCTURAL SYSTEMS] COLUMNS

Columns are rigid, relatively slender structural members designed primarily to support axial compressive loads applied to the ends of the numbers (Ching 2008, 2.13).

•  Short Columns •  S h o r t , t h i c k

c o l u m n s a r e subject to failure by crushing rather t h a n b u c k l i n g ( C h i n g 2 0 0 8 , 2.13)

•  Column length: smallest cross-section dimension is lesser than 12:1 (ex. 3000:300)

•  Long Columns •  Long, slender columns are

subject to failure by buckling rather than by crushing (Ching 2008, 2.13)

•  Column length: smallest cross-section dimension is greater than 12:1 (ex. 3000:100)

1 http://degenkolb.com/images/uploads/2011/10/Copy-of-SAM_0685.jpg 2 http://static.dezeen.com/uploads/2013/06/dezeen_Harmonie-Hall-by-Takenaka-Corporation_8.jpg 3 http://www.expol.co.nz/images/masonryWall.gif 1

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FRAMES & WALLS

If the joints connecting the columns and beam are capable of resisting both forces and moments, then it becomes a rigid frame (Ching 2008, 2.17)

•  Fixed Frame: rigid frame connected to its supports with fixed joints

•  Hinged frame: rigid frame connected to its supports with pin joints

•  Three-h inged f rame: s t ruc tu ra l assembly of two r igid sect ions connected to each other and to its supports with pin joints

•  More on frames in Ching 2008, 2.17

If the plane defined by two columns and a beam is filled, it becomes a loadbearing wall that acts as a lon, thin column in transmitting compressive forces to the ground (Ching 2008, 2.17).

If the plane defined by two columns and a beam is filled, it becomes a loadbearing wall that acts as a lon, thin column in transmitting compressive forces to the ground (Ching 2008, 2.17).

•  Masonry Walls: modular building blocks bonded together with mortar to form walls that are durable, fire resistant and structurally efficient in compression (Ching 2008, 5.14)

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[STUDIO] Task: Create a model of the assigned plan from the Oval Pavilion

Our group was assigned to a part of the metal deck roof along with the plant room in the basement. To create this, we used many different materials such as foam board, cardboard and balsa wood. The foam board was used for the base or “slabs” for the floor/ or ceiling. This was also used to create the studs, which can be found in the 5th photo. On the other hand, the balsa wood was used for the walls.

To achieve our model, we had to refer to the architectural and structural plans to know the dimensions, materials and elements that were used. The beams and columns in the 5th photo were mostly steel framings.

In real life, the walls would contain insulations and flashings as well. It also consists of block work and brickwork.

Oval Pavilion Redevelopment; The University of Melbourne Basement Plan A 21-01

Oval Pavilion Redevelopment; The University of Melbourne Ground Floor Plan A 21-02

Oval Pavilion Redevelopment; The University of Melbourne Building Details – Wall Details A 46-03

Oval Pavilion Redevelopment; The University of Melbourne Building Details – Roof & Façade A 60-02

Oval Pavilion Redevelopment; The University of Melbourne Roof Framing Elevations S04.02

[WEEK 06]

[STUDIO] Task: Site Visit Presentations

PLATE STRUCTURES (Ching 2008, 2.18)

•  Rigid, planar, usually monolithic structures that disperse applied loads in a multidirectional pattern, which the loads generally following the shortest and stiffest routes to the supports.

•  Ex. Reinforced concrete slab •  It should be a square or nearly a

square for it to behave as a two-way structure

•  Rectangular ones = one way-system spanning the shorter direction

•  Shorter plate strips are stiffer & carry greater portion of the laod

•  Folded Plate Structure •  Thin deep elements joined

rigidly alone their boundaries and forming sharp angles to brace each other against lateral buckling.

•  Space Frame •  Short, rigid linear elements

triangulated in 3D and subject on ly t o ax ia l t ens ion o r compression.

•  See Ching 6.10 & 6.11 as well for more

1 http://www.columbia.edu/cu/gsapp/BT/BSI/SHELLS_BM/concrf-1.jpg 2 h t t p : / / w w w . d p m f a b r i c s t r u c t u r e s . c o m / f i l e s /DPM_Space_Frame_Potomac.jpg

1

2

http://thumbs.dreamstime.com/x/steel-truss-5644473.jpg

[WEEK 07]

[STRUCTURAL CONCEPTS] ARCHES

•  Curved structures for spanning an opening, designed to support a vertical load primarily by axial compression (Ching 2008, 2.25).

•  Transform vertical forces of a supported s u p p o r t e d l o a d i n t o i n c l i n e d components and transmit them to abutments on either side of the archway


DOMES SHELL

•  Spherical surface structure having a circular plan and constructed of stacked blocks, a continuous rigid material like reinforced concrete, or of short, linear elements as in the case of a geodesic dome

•  Similar to a rotated arch except circumferential forces are developed that are compressive near crown and tensile in lower portion


•  Thin, curved plate structure typically constructed of reinforced concrete

•  Shaped to transmit applied forces by membrane stressed

•  Can sustain relatively large forces if uniformly applied

•  Its thinness creates little bending resistance and is unsuitable for concentrated loads


1 http://s0.geograph.org.uk/photos/66/79/667977_53fc6b26.jpg 2 http://www.romanobritain.org/Graphics/arc_arch_construction.gif 3 http://s95.photobucket.com/user/nothingbettertodo_2006/media/Copenhagen/Dome2.jpg.html 4 http://www.astrodomes.com/photos/aloka/enl/f812.jpg 5 http://upload.wikimedia.org/wikipedia/commons/4/40/Sydney_Opera_House_Sails.jpg 6 http://cdn.archinect.net/images/1200x/kz/kz7tq6x9u2nmrgv8.jpg

[WEEK 08]

Steel angle fixed to header beam, PT-13 ( p a i t t o e x p o s e d structural steel

Continuous welded tab Continuous welded tab

Timber

100mm x 200mm S t e e l R H S ( R e c t a n g u l a r Hollow Section)

Structural Silicone

Glass / glazing

Vapour barrier: any material used for damp proofing, usually plastic or foil sheet to avoid moisture passing into interior spaces

Steel angle recessed into concrete slab

W o r k e d concrete finish

Steel angle fixed to base angle

Steel RHS G l a s s , glazing

The drawing was a section of the glass (in the middle).

20mm

This was the bottom part of the structure. It is the one that touches the concrete slab at the exterior of the building.

Oval Pavilion Redevelopment; The University of Melbourne Building details – function room A 60-03

OPENINGS: DOORS AND WINDOWS

DOORS (Ching 8.02 and 8.10) •  Parts:

•  Door leaf: top rail, stile (side frame), feature panel, glass/hollow/solid core infill, mid-rail, bottom rail (Ching 8.09)

•  Handle, latch and lock •  Door Swing •  Sill / Threshold •  Architrave •  Stop •  Jamb •  Head •  Rough opening

* See Ching 8.03 for labeling

•  Timber doors and frames (Ching 8.10) •  Aluminum doors and frames

•  Can also be a timber frame •  Steel doors and frames (Ching 8.17)

•  Can be used for security purposes

WINDOWS (Ching 8.23) •  Think about how it will be cleaned •  Parts:

•  Head detail •  Jamb detail •  Sill detail

•  Timber windows and frames (Ching 8.27)

•  Aluminum windows and frames (Ching 8.24)

•  Very commonly used in commercial buildings

•  Glazing is quite complex •  New architecture building: there

is still lintel above to carry the load on top of it

•  Steel windows and frames (Ching 8.25) •  More expensive and not so

commonly used •  Thermal break = produces heat

loss •  Curtain walls

•  Before putting windows into walls, you have to think about the load – it has to be around the window not through it

Ching (2008), 8.13

[WEEK 09]

[CLASS SITE VISIT] The site was located in Spencer St. where there will be 4 towers once everything will be done. Construction is done quickly where they use methods that would quicken the process. 1 level of slab is placed every 5 days, which is fast. The panels in the site are pre-cast and a lot of the structures so far are temporary. This means that there will be plenty of bracings and other structures removed when another structure can carry itself already.

Jump form are little holes on concrete elements. It can be found in the site and is a method that was commonly used. This allows faster construction, increases speed and is very efficient.

These holes ties together and fasten jump forms. T h e f o r m w o r k i s independently supported so shear walls and core walls can be completed ahead of the rest of the main building structure

At the bottom of slabs would be a timber formwork.

Post tensioning cables will be tied on these edges, which will lock it so there will be no more movement with the slab. These cables would be steel cables or PT strands.

These are hydraulic jacks which would go into a PT cable. It tenses the cable and measures its stress. This would be covered to avoid trip hazards. The cable sticking out would be cut off later on after filling it in with grout.

The steel columns on site have cables and more steel wrapped around it. However, it is not load-bearing as it only holds it together.

Steel reinforcements are also found in the site. Those were just waiting for the concrete slab to be put in. There were also starter bars which were tied into a column below, which were also waiting for the next slab to be put in.

There are also peril props that can be found in site, which they used instead of scaffolding because it takes a longer time. They are able to form a floor within a day and when it cures, they are able to remove these peril props. Other than per i l props and steel reinforcements, they have different penetrations on the slab as well such as nailing a fire collar.

[WEEK 10]

[GLOSSARY]

A Alloy – a metal made by combining 2 or more metallic elements; can give greater strength/resistance to corrosion Apex – top or highest point of something; a corner or edge Axial Load – the force acting along the lines of an axis of an object; may result to compression or tension B Beam – Rigid structural members designed to carry and transfer transverse loads across space to supporting elements (Ching 2008, 2.14) Bearings – The fastenings at the places where the main load carrying members (beams or trusses) touch down on the abutments or piers. Bending – to shape or force something straight into a curve or angle Bracing – To stabilize the main girders during construction. Cross bracing is reinforcing building structures where diagonal members intersect.

Buckle – to bend or give away under pressure or strain. It is the sudden lateral or torsional instability of a slender structural member induced by the action of an axial load before the yield stress of the material is reached (Ching 2008, 2.13) C Cantilever – a long projecting beam or girder fixed at only one end Column – Columns are rigid, relatively slender structural members designed primarily to support axial compressive loads applied to the ends of the members (Ching 2008, 2.13). Columns will tend to buckle if the dimension is not equal. Composite Beam – a steel beam, which has concrete decking above it and is connected to the concrete by shear connectors, causes the steel and concrete to act together; both will share the load Compressive Force – the pressure that acts to compact or squeeze something together Cornice – an ornamental moulding around the wall

h t tp : / /up load.w ik imed ia .o rg /w ik iped ia /commons/c /c0 /Brick_Cornice_Molding.jpg

Concrete – building material made from a mixture of stone/gravel, sand, cement and water Crossbeam – a beam extending across something (diagonally) D Deflection – perpendicular distance a spanning member deviates from a true course under t ransverse loading, increasing with load and span, and decreasing with an increase in the moment of inertia of the section or the modulus of elasticity of the material (Ching 2008, 2.14). Down pipe – pipe to carry rainwater from a roof to a drain or to ground level Drip – A metal strip that extends beyond the other parts of the roof and is used to direct rainwater off E Eave – A part of the roof that meets or overhangs the walls of a building Efflorescence – usually a white powdery substance that can appear on masonry walls after construction Expansion Joint – a joint that makes allowance for thermal expansion of the parts joined without distortion

F Fascia – a wooden board or other flat piece of material such as that it covers the end of rafters Fastening – to secure something Flashing – a strip of metal used to stop water penetrating the junction of a roof with another surface Force – an external effort that causes an object to undergo a certain change with movement, direction or geometrical construction. Frame – The fitting together of pieces to give a structure support and shape. Friction – the resistance that one surface or object encounters when moving over another G Girder – large iron or steel beam or compound structure used for building bridges and the framework of large buildings Gutter – a shallow trough fixed beneath the edge of a roof for carrying off rainwater I Insulation – material designed to prevent heat or sound from being transmitted from one area to another

J Joints – a point at which parts of a structure are joined Joist – a length of timber or steel supporting part of the structure of a building, typically arranged in parallel series to support a floor or ceiling. K Kiln – a furnace or oven for burning, baking or drying Kink – a sharp twist or curve in something that is otherwise straight L Lateral Stability – The ability of a material to remain upright and not tip over sideways. A load that is out of balance or on an uneven surface can affect lateral stability. Lintel – a horizontal support of timber, stone, concrete or steel across the top of a door or window. M Masonry – A form of construction in which structures from individual units are laid in and bound together by mortar such as stonework or brickwork Moment – a turning effect produced by force acting at a distance on an object

Moment of Inertia – measure of an object’s resistance to changes to its rotation; capacity of a cross-section to resist bending N Noggin - short horizontal wooden beam used to strengthen upright posts in the framework of a wall P Pad Footing – simplest and cost-effective footing used for the vertical support and the transfer of building loads to the ground Pane – single sheet of glass in a window or door Panel – flat or curved component, typically rectangular, that forms or is set into the surface of a door, wall, or ceiling Parapet – low protective wall along the edge of a roof, bridge, or balcony Perpend – a vertical layer of mortar between two bricks Piers – upright support for a structure or superstructure Point load – A load that is applied on one point. It is where structural weight is intense and transferred to the foundation. Applied loads are given as distributed loads are forced

Portal Frame – rigid structural frame consisting essentially of two uprights connected at the top by a third member Purlin – horizontal beam along the length of a roof, resting on principals and supporting the common rafters or boards R Rafter – a beam forming part of the internal framework of a roof Reaction Force – At the ground, the applied load has a reaction. Meaning the whole structure is stable and that reaction is that it’s equal and opposite of the applied load. Retaining Wall – wall that holds back earth and may be constructed from timber, concrete, steel, masonry, and rock or combination of any of the mentioned materials S Sandwich Panel – (Aluminum composite panel) is a type of flat panel that consists of two thin aluminum sheets bounded to a non-aluminum core. Sealant – material used for sealing something so as to make it airtight or watertight Seasoned Timber – timber dried to moisture content that is stable

Stress – pressure or tension exerted on a material object Stretcher Face – long face of a brick Strip Footing – supports the slab, also called “edge beams”, small strip of concrete placed into a trench and reinforced with steel Structural Joints – Roller joint, Pin Joint and Fixed Joint; See Ching 2.30 or Week 2 Strut – a rod or bar forming part of a framework and designed to resist compression Stud – large-headed piece of metal that pierces and projects from a surface, especially for decoration Substructure – underlying structure forming the foundation of a building (Ching 2008, 2.03; see Ching 3.02) Superstructure – vertical extension of a building above the foundation (Ching 2008, 2.03)

Shear Force – unaligned forces pushing one part in one direction and another part in the opposite direction Shear Wall – wall composed of braced panels to counter the effects of lateral loads acting on a structure Sill – a shelf or slab of stone, wood or metal at the foot of a window opening or doorway Slab – large, thick, flat piece of stone or concrete, typically square or rectangular in shape Soffit – the underside of an architectural structure such as an arch, balcony, or overhanging eaves Skirting – wooden board running along the base of an interior wall Spacing – the distance from centerline to centerline of two things Span – the full extent of something from end to end Steel Decking – used to support spans or a continuous slab Steel Gusset Plates – used to connect beams and girders to columns or to connect truss members

T Taper – diminish or reduce thickness towards one end Tension - state of being stretched tight Top Chord – top beams in a truss, generally in compression Torque – a force that tends to cause rotation Torsion – the action of twisting or the state of being twister, especially of one end of an object relative to the other Truss – structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes V Vapour Barrier – used to refer to any material for damp proofing, typically a plastic foil sheet, that resists diffusion of moisture through wall, ceiling and floor assemblies of buildings and packaging W Window Sash – a framework that holds the panes of a window in the window frame

REFERENCE: Ching, F. (2008). Building Construction Illustrated. John Wiley & Sons, Inc., Hoboken, New Jersey. *Most definitions in glossary is from Apple dictionary

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