Tutorial on Ple 4 edu

Tutorial on Tutorial on PlePle44eduedu

Educational version of PLE, THE software for strength and stability design of (buried) pipelines

After downloading

and installation,you will find this shortcut

on your desktop.

Double click to start the

program

The total tutorial will take about 50 min., but of course you can click to proceed faster.

1Tutorial version 1.2

Some tipsSome tipsUse this presentation within Powerpoint 2003 or later because of the animations contained

The presentation performs automatically and you can use the standard action buttons(down left).

In case you want to skip screens, you can use the right mouse button.

In case you want to pause the presentation, you may use as well the Pause/Break key on the keyboard (toggle).

2

To open a table from an overview list, it is indicated as “Click”. This may be a ‘double click’ or a ‘single click+show button’

After clicking the shortcut the program will startup and will result in the following screen:

ROADMAP panel

OVERVIEW panel

WORKSPACE panel

Use this icon to show or hide the ROADMAP

panel

Use this icon to show or hide the OVERVIEW

panel

Use this icon to show or hide the WORKSPAC

Epanel

..and if you are lost…use this icon

to restore the

default panel layout

LayoutLayout

3

We will now open a new ‘project’ and name it DEMO CASE

Open new empty project

Demo case

…and

‘save’

Optional ‘project name’

Design function 1Design function 1

Optional ‘project description’

4

soil settlement

Demo caseDemo case

Pipeline, crossing an old refilled ditch causing large soil settlements

PipeSoil

Pipeline bending stiffness partly resists deformation

15 m

Questions:

1. To what extent will the pipeline follow the soil settlements?2. What is the maximum stressing of the pipeline?

5

Limitations of educational Limitations of educational version version

General model only (no Code dependent General model only (no Code dependent features)features)

Maximum number of 50 elements (51 nodes)Maximum number of 50 elements (51 nodes) No print or import/export optionsNo print or import/export options No advanced options (branches, No advanced options (branches,

T-pieces, offshore, articulated, towing, material T-pieces, offshore, articulated, towing, material yielding, construction phasing etc)yielding, construction phasing etc)

But non-linear soil and geometrical behaviour But non-linear soil and geometrical behaviour included…..included…..

and of course free use for educational and of course free use for educational purposespurposes

6

ModellingModelling

As a result of the limited availability of elements and the symmetry of the questions to be answered, the model will be cut at the mid settlement section, and at the other end far enough away from the settlement section to avoid interaction.

Symmetry axis

soil

pipelinerigid, vertical roller support

main settlement area500 mm

construction subsidence 2 mm

Elastically supported, half infinite pipeline connection

7

Subdivision into Subdivision into elementselements

Symmetry axis

main settlement areaconstruction subsidence

Main points

M

1. M at mid point

M1

100

2. M1 near M to obtain near support internal forces

R

3. R at settlement transition

R1 R2

4. R1 and R2 near R for same reason

100 1007300

O

5. O at end of pipeline section considered

C

6. C at estimated point of maximum bending moment

2500 13500

1*100

elements15*487 2*100 5*500 27*500

total nr elements = 50

8

Global coordinate systemGlobal coordinate system

X-axis almost along pipelineX-axis here from M to O

Y-axis, horizontal and perpendicular to X-axis(right handed)

Z-axis, perpendicularto X and Y axes, and pointing upward(right handed)

ORIGIN

9

Now we will input the pipeline shape into the program.

This is done in Design function 2

Click on DF2‘Pipeline

Configuration’

Click on the ‘default’ icon to get default ORIGIN-data (if not yet available use

the ‘more buttons’ facility)

Click on the required ‘test’ icon to check

the input data (if not yet available use

the ‘more buttons’ facility)

Close table

Replace ‘start’ by

‘M’

Click on‘Pipeline origin’

Design function 2Design function 2

10

Now the polygon has to be defined by means of the polygon points and their X- and Y-distances relative to the previous point and their absolute Z-value.In this case all Y and Z-values remain zero.

At the polygon points the radius of the pipe bend is provided.In this case there are no bends and this is specified by R = 0

The length of ‘pipe elements’ is specified per line between thepolygon point and the previous point.

Point NPoint N+1

Point N-1

line N

line N+1

X(N) X(N+1)

Z(N)

Z(N+1)Element length line N

R(N)

PolygonPolygon

11

Next we have to input the polygon points with lines attached

clickSymmetry axis

M M1

100

RR1 R2

100 1007300

OC

2500 13500

1*100 15*487 2*100 5*500 27*500

The table is rearranged a bit to

fit all columns on the workspace. This can be done as well by

hiding the roadmap.And the workspace is enlarged vertically

‘ENTER’ to get a new line

next point

…and so on

Test..

…and close

Polygon tablePolygon table

12

All required data for this function has been provided and we will now process the function to be sure that indeed we do not exceed the allowable number of elements in this educational version

Click here to process

the function

Input tables are ‘locked’ because the

results of this input are

stored in the project

database

If you want to open the input tables

again, click here to ‘set back’ the

function.Results are

removed from the project database in

order to remain consistent.

Locked tables & Set backLocked tables & Set back

13

Let’s have a look at the results of this function.

For reason of clarity here the input tables list is hidden and the output tables list is made visible.

Hide input tables list

Check this box to show the output tables list

Click to see the

‘NODES’ list

Click here to maximize the

workspace

Scroll to end of table

Indeed there are no more

than 51 nodes.

Check on node numberCheck on node number

14

The pipeline axis has been defined now and we proceed with specification of the pipe/soil properties in the Y-Z plane perpendicular to the pipeline axis

Pipe axis

Pipe properties DF 3.1

Pipe/Soil properties DF 3.2

Boundary conditions D

F 3.3

Eventually external supports

DF = Design Function

Boundary conditionsBoundary conditions

15

Pipe data (DF3.1)Pipe data (DF3.1)

All data in N – mm All data in N – mm - - ooCC

Pipe material steelPipe material steelE = 2.1 10E = 2.1 1055 N/mm N/mm22

= 0.3 = 0.3 = 12 10 = 12 10-6-6 mm/mm/ mm/mm/ooCC

Pipe dimensionsPipe dimensionsDDoo = 1010 mm = 1010 mmWT= 10 mmWT= 10 mm

Deadweight ignoredDeadweight ignored

Do

WT

16

Click ‘Pipe data’ Click ‘material

location’

Reference name of

material to be

specified

X-coordinate where this material

starts

Test and

Close

Material location tableMaterial location table

17

Hide roadmap panel to

free space for tables

Click ‘isotropic materials’

Use ‘test’ icon to see which data are

‘required’Column headings

speak for themselves

Test and

Close

Shear modulus G is calculated from E and ,

but can be overruled by an

input datum

Isotropic material tableIsotropic material table

18

Click ‘Outer diameter’

Procedure as before

Test and

Close

Pipe diameter tablePipe diameter table

19

Same procedure

Click ‘Wall thicknesses’

Test and

Close

Pipe wall thickness tablePipe wall thickness table

20

In the tables seen so far, there often is a double set of input data, like for instance the wall thicknesses table we just passed:

Data set 1

Location of transitionfrom data set 1 to 2

Data set 2

If on a row items of data set 2 are not provided, it means by default item (2) = item (1)

If on row N items of data set 2 differ from the same items in data set 1, then there is a ‘jump’in the data line of that item at point XP(N).

If on row N+1 items of data set 1 differ from the same items in row N data set 2, then there is a linearpath from N to N+1 over the line from XP(N) to XP(N+1).

XP(N)

Item (N,1) = Item (N,2)

XP(N+1)

Item (N+1,1) = Item (N+1,2)

linear

XP(N-1)

Item (N-1,1) = Item (N-1,2)

XP(0)

by default

XP(end)

by default

(specified) (specified) (specified)

Data entry explanationData entry explanation

21

Pipe/soil interaction Pipe/soil interaction upwardupward

grade

Pipe displaces upward relative to the soil or the soil moves downward relative to the pipe.Soil reaction on top of pipe pointing downward.

Vertical soil stiffness upward [ KLT, N/mm3 ]

Vertical passive soil reaction upward [ RVT, N/mm2 ]

R

KLT

RVT

22

grade

Pipe displaces sideward relative to the soil or the soil moves sideward relative to the pipe in the other direction.Soil reaction at side of pipe pointing opposite the displacement direction.

Horizontal soil stiffness [ KLH, N/mm3 ]

Horizontal passive soil reaction [ RH, N/mm2 ]

R

KLH

RH

Pipe/soil interaction Pipe/soil interaction sidewardsideward

23

Pipe displaces downward relative to the soil or the soil moves upward relative to the pipe.Soil reaction at bottom of pipe pointing upward.

Vertical soil stiffness downward [ KLS, N/mm3 ]

Downward passive soil reaction [ RVS, N/mm2 ] (bearing capacity)

R

KLS

RVS

grade

Pipe/soil interaction Pipe/soil interaction downwarddownward

24

Pipe/soil interaction Pipe/soil interaction generalisedgeneralised

Vertical soil stiffnessKLS = 1.10-3 N/mm3

Horizontal soil stiffness KLH = 1.10-3 N/mm3

All directions soil stiffnessKL(

Upward ultimate passive soil resistanceRVT = 19.81 10-3 N/mm2

Downward ultimate passive soil resistance(bearing capacity)RVS = 100 10-3 N/mm2

Horizontal ultimate passive soil resistanceRVT = 19.81 10-3 N/mm2

All directionsultimate passive soil resistanceRV()

Extrapolation to all directions

25

Pipe displaces or rotates longitudinally relative to the soil.Soil friction reaction around pipe opposes movement of the pipe.

Ultimate elastic friction displacement [ UF, mm ] in this case 5 mm

Ultimate soil friction reaction [ F, N/mm2 ] in this case 5 10-3 N/mm2

RF

UF

Movement of pipe

Friction of soil

Movement of pipe

Friction of soil

Pipe/soil interaction axialPipe/soil interaction axial

26

Click ‘Soil data’

Hide Roadm

ap

Click horizontal soil stiffness

In this case all soil data are considered to be constant

over the pipeline

length, so we can start at

XP=0

‘Dividing’ and ‘Multiplication’

factors are ‘uncertainty factors’

on the soil data.Use for the time being the default

values

‘Half band width accuracy’ is

parameter to control the iteration accuracy on the soil reactions.

Use for the time being the default

values.Test and

Close

Soil data (DF3.2)Soil data (DF3.2)

27

The other soil data

are provided in the same

way

Click KLS

Test and close

Click F

The upward soil stiffness is equal to

the downward stiffness in this case and the table can be

left empty

Test and close

Click UF

Test and close

Click RVS

Test and close

Click RVT

Test and close

Click RH

Test and closeClick UNCER

Select for each soil parameter

‘mean’, meaning that

no variation on the soil

parameters is applied.

Test and close

Soil data tablesSoil data tables

28

Explanation on the uncertainty factorsUncertainty factors represent the uncertainty in the pipe/soil data. Soil data may differ from location to location, but there is also uncertainty in the methods of measurement of basic soil data and variation in calculation methods of pipe/soil parameters from these basic soil data.

The uncertainty factors create upper (multiplication) and lower (division) boundary values for the pipe/soil parameters in order to achieve conservative stress and strain calculation results for the pipeline.In general a stiff soil (upper values) generates conservative results in case of ‘deformation driven’ loadings (e.g. settlements, tempera-ture loadings, etc.) and a weak soil (lower values) conservative results in case of ‘force driven’ loadings. (e.g. concentrated deadweights, upheaval buckling, etc.)

‘mean’ value of soil stiffness Km

‘mean’ value of ultimate soil resistance RmRm

Ku

Km

Kl

Ru

Rl

‘stiff ‘soil performance

‘weak’ soil performance

Default values for the uncertainty factors are taken from theDutch pipeline code NEN 3650.

Uncertainty factorsUncertainty factors

29

Explanation on the ‘band width accuracy’Soil is a non-linear material in the sense that in case of a loading there is an elasto-plastic relationship between the reaction force and the related displacement.However, all FEM (finite element method) programs (like PLE) arebased on linear solution methods (N equations with N unknowns).This means that iterations are required to ‘follow’ the non-linear behaviour of the soil.

R

A bilinear R- relationship is shown,but PLE offers various curved relationships as well.

soil stiffness iteration 1: K1

(R- as result from iteration 1

5% band width

5% band width







Result fulfils R- condition

Band width accuracyBand width accuracy

30

Boundary conditionsBoundary conditionsNext step is to specify the boundary conditions at both ends of the piece of pipeline considered. The piece is cut out of a long pipeline and this shall not affect the local behaviour of the pipeline due to the local loadings.

There are three options to choose from:1. INFINITE meaning the pipeline continues, but displacements

at this end point shall stay within elastic limits,2. FREE meaning the endpoint is free to move without constraints,3. FIXED meaning the end point is rigidly fixed in all directions.

INFINITE FREE FIXED

Boundary conditions (DF3.3)Boundary conditions (DF3.3)

31

Boundary conditionsBoundary conditions

And at a boundary there are two options for the end condition:

OPEN: At an INFIN boundary, loadings (pressure, temperature, settlements) continue over the connected half infinite long pipeline.At a FREE boundary, the medium flows out freely without any restraint.At a FIXED boundary, loadings are counteracted by the support.

CLOSED: At an INFIN boundary, loadings (pressure, temperature, settlements) are

stopped at the connection to the half infinite long pipeline. At a FREE boundary, the pipeline is capped. At a FIXED boundary, internal loadings are counteracted by

a cap.

Boundary conditions tableBoundary conditions table

32

Boundary conditionsBoundary conditionsIn our case we will attach an INFINITE boundary condition to the right end of thepipeline.

The left boundary is a special case, because the boundary condition shall represent the symmetrical behaviour of the pipeline.To that purpose we attach a FREE end and attach as well an external support.

This external support shall fix this free end in all directions, except in the Z-directionto simulate the vertical roller support. The stiffness properties of the support “ROLLER’ are specified in a separate table and this support is attached to the point M in another table.

INFINITEFREE

Boundary conditions applicationBoundary conditions application

33

Show roadmap

Select ‘model

boundary’ and hide roadmap

again

Click ENDPTS

Test and close

Click ELSPRL

Test and close

Click ELSPRS

Test and close

Additional boundary conditionsAdditional boundary conditions

34

Show roadmap

againThe last three DF’s we have completed the data without processing the

functions.We will now use the

PROCESS function on the Roadmap to

process all completed functions up to the

function that cannot be processed

Process functionProcess function

35

LoadingsLoadingsUp till now we focused on the structural items of the pipeline structure, the shape of the pipeline, the geometrical and stiffnessitems of the pipe cross section, pipe/soilmechanical data and finally the structural boundary conditions.From these data the structural stiffness matrix can be composed.

Now we have to specify the loadings that act on or within the pipeline structure. Distinction is made between the loadings thatact on the pipeline structure as a ‘beam’ and the loading that work locally on the pipeline as a series of ‘rings’.

‘beam’ behaviour

‘ring’ behaviour

‘‘Beam’ and ‘Ring’ loadingsBeam’ and ‘Ring’ loadings

36

‘‘beam’ loadingsbeam’ loadings• internal or external pressure (especially the ‘Poisson’-effect)

• temperature variations

• soil settlements (3 directions) and construction subsidences

• nodal force systems

Ring expansion due to internalpressure

Axial contraction due to internal pressure

Pipe stiffness resists soil settlement

‘‘Beam’ loadingsBeam’ loadings

37

Loadings Loadings (DF4.2)(DF4.2)

Click ‘Pipeline loading’

Click SETZ

Mind the minus sign!

(Pos. Z-axis upward)

Mind the jump function at

XP=7500 mm

Test and close

Process function

38

‘‘beam’ calculationbeam’ calculationThe structural data and loading data are available now and we proceed with the actual calculation of the pipeline as a ‘beam’.To that purpose first the load combination has to be constituted from the various load cases provided in the previous function.This is done by specifying a ‘general load factor’ applicable to all load cases and ‘partial load factors’ per load case.

In this case we will set the general load factor to 1 and the soil settlement factor to 1 as well. All other factors are set to 0.

‘‘Beam’ calculationBeam’ calculation

39

Click ‘Pipeline behaviour’

Click LOCASE

Test and close

Click GEOCTL

Use default values

Test and close

Process function

Loading combination tableLoading combination table

40

‘‘Beam’ resultsBeam’ resultsLet us have a look at the results of the ‘beam’ calculation.To that purpose we open the tables: displacements, internal forces and soil reactions. Keep in mind, that most results are given as a scalar entity with angle of the vector.

orX

Z

displacement

XY

ZM

M

bending moment

YX

M

R

Z

R

soil reaction

or

For instance:

41

uncheck

check

Click displacementsClick internal forcesClick soil reactions

These three tables are ‘open’ now

Maximise Workspace

As a table provides little information on the coherence of the contained datawe will make a ‘single graph’, starting with a N-Z graph.

Click here Hold down ctl-key and click here

And click thenhere on the

single graph icon

Z-displacements(max. about 60 mm)

Nodes located on their X-coordinate

Click on axis to toggle to the X-coordinates

Go back to the ‘displacements’

table

Click here with ctl key down

….and click on S-graph icon again

Rotation graph is

added with its own scaling

Single graphSingle graph

42

…and go to ‘internal forces’

Close graph

click Ctl+click

..and click S-graph

Ctl+click

M=180o M=0o

close graph

…and go to ‘soil

reactions’

click Ctl+click Ctl+click

click

R=270oRVT

soil failure on top of pipe

R=90o

R=270o

close graph

…and go back to

‘displacements’

Multi graphMulti graph

43

Ctl+click

We will now compare the Z-displacements of the pipeline with the soil settlement load,using the multi-graph facility.

Click themulti-graph icon

Click OK

Show roadmap

Click pipeline loading

Click Overview

Click the elaborated ‘Pipeline loads’

Click Ctl+click

Click M-graph icon

Click themultiple tables

graph icon

Click OK

Show Overview

Link X2 to X1 Link Y2 to Y1Set Ymin to -500 mmSet Ymax to 0 mm

ClickShow the graph

The pipeline does not

follow the settlement and ‘spans’

the settlement

area.

Close graph

…and restore default layout

Multi graph specificationMulti graph specification

44

Stress calculation Stress calculation schemeschemeNow the internal forces are known, the stresses in the cross sections

(at the mid-elements) can be calculated, after some additional data is provided:

• the overburden load distribution

• eventual additional top load distribution (e.g. traffic load)

• horizontal grain pressure as ratio of the vertical grain pressure

• bottom support angle

180oDistribution along pipeline

180oDistribution along pipeline

120o

45

Click ‘Cross-section

data’

Hide roadmapClick

‘Neutral soil load’

Test and close

No extra top loadsClick

‘Horizontal soil support’

Test and close

Click ‘Soil support

angle’

From 0 to 50%Min. support angle = 70o

From 50 to 100%support angle grows from 70o to 180o

Grow curveis sinus

Test and close

process

Stress calculation tablesStress calculation tables

46

Stress calculation resultsStress calculation results

Finally we reached the point where we can make the stress calculations in the cross sections of the pipeline, as all data are available now.The only thing still to do is to specify the cross sections where the stresses have to be calculated and whether or not the additional top load has to be taken into account. (In this case there is no top load)The ‘allowable stress’ to be specified is for overstressing indication only.

In the various stress output tables the stress components are explained.In the regular stress output tables (‘max’-tables) only the extreme value of a stress component per cross section is shown and as a result related stress components are not necessary located at the same point of the cross section.

In the additional output tables the detailed stress components over the circumference at the inner and outer wall side are shown of the last specifiedcross section in the table SECTION.

47

Cross Cross section section tabletable

Click ‘Cross section behaviour’

Click table SECTION

First elementLast element 72% of yield

Test and close

Process function

48

uncheck

check

Hide roadmap

Click max. check stressesClick ‘Max’ icon

MaximumVon Mises stress

at element 19

Maximum Von Mises stressMaximum Von Mises stress

49

Stress results coordinate Stress results coordinate systemsystem

Additionally to the global coordinate system explained before, there is an additional coordinate system within the cross section

X [mm]

Y [mm]

Z [mm]

[mm]

Inner wall side [i ]

Outer wall side [o ]

Mid wall [m]

50

Collection of all cross sectional dataCollection of all cross sectional loading data

Click max. stresses in straight pipe

Hide Overview

Stresses due to internal forces in the ‘BEAM’

Stresses due to AXIAL FORCEUniformly distributed over circumferenceUniformly distributed over wall thickness

, ,0x u (SXUBO)


Stresses due to BENDING MOMENTLinearly distributed over circumferenceUniformly distributed over wall thickness

, ,1x u (SXUB1)


Stresses due to TWISTING MOMENTUniformly distributed over circumferenceUniformly distributed over wall thickness

, ,0z u (TZUB0)


Stresses due to SHEAR FORCESine shaped over circumference

Uniformly distributed over wall thickness

, ,1z u (TZUB1)

Maximum ‘beam’ stress tableMaximum ‘beam’ stress table

51

MaxMaximuimum m

‘rin‘ring’ g’

strestress ss

tabltablee

Bends not available here Click ‘Max stresses from lateral loadings’

Hide Overview

Stresses due to PRESSURE on the ‘RING’

Stresses due to HOOP FORCEUniformly distributed over circumferenceUniformly distributed over wall thickness

, ,0u (SFUBA)

Stresses due to internal forces in the ‘RING’

Stresses due to CIRCUMFERENTIAL FORCELoad dependently shaped over circumferenceUniformly distributed over wall thickness

, ,u A (SFURA)


Stresses due to CIRCUMFERENTIAL SHEAR FORCELoad dependently shaped over circumferenceParabolicly distributed over wall thickness

, ,x m A (TXMRA)


Stresses due to CIRCUMFERENTIAL BENDING MOMENTS

Load dependently shaped over circumference

, ( )i innerwall, ( )o outerwall

, ( )X i innerwall

, ( )X o outerwall

Linearly distributed over wall thickness (both X and )

, , , , , ,, *i i i

o o oA X A A

(SFIRA, SFORA, SXIRA, SXORA)

52

MaxMaximuimum m

strestress ss

comcomponponententss

Click ‘Maximum total stresses

…and hide ‘Overview’

Maximum stress componentseach the maximum of the component in the cross section

sxit-maxsxot-max

sfit-max

tzut-max

sfot-max

txmt-max

seit-max Von Mises

Locations of maximum stress components arbitrarily chosen for clarity

53

seot-max Von Mises

Maximum Maximum principal principal stressesstresses

Click ‘Maximum principal stresses

1 ,i M2 ,i M

,i M

1, ,o M2, ,o M

,,o M

Extreme principal stresses at outer wall side

Extreme principal stresses at inner wall side

123

54

Maximum check Maximum check stressesstresses

Click ‘Maximum check stresses’

Max. principal

stress in any point of the

cross section

Extreme negative principal

stress in any point of the

cross section

Max. shear principal stress in any point of

the cross section(third principal

stress taken into account)

Max. Von Mises stress in any point of the

cross sectionMax.

circumferential stress in any point of the

cross section

Max. axial stress in any point of the

cross section

Max. hoop pressure stress in any point of

the cross section

55

Maximum Maximum radial radial

deformatiodeformationsns

Click ‘Maximum radial deformations

Click ‘Extremes’-icon

The maximum radial deformation is -7.45 mm (inward, indicated by minus sign)2

1 = 7.45 mm

D = 1 + 2 = 1.3% of D = 0.013*1000 = 13 mm

56

Detailed stresses at maximum Detailed stresses at maximum stressed sectionstressed section

You may recall, that the maximum Von Mises stress in the pipeline occurs in element 19and amounts to 122 N/mm2.

The last calculated section, specified in the table SECTION, is stored with all its detailed stresses. So in order to make these detailed stresses available for further analysis,the section 19 has to become the last section to be calculated.In order to do so, the DF6 is set back and element 19 is added to the list and the function is processed once again.

57

AAdddd mmaaxx.. ssttrreesssseedd sseeccttiioonn

Click Set Back button of DF6

Yes

Click Section table

Add section 19, test table, close table and process the function

(on the roadmap)

uncheck

Check and hide roadmap

58

Relationship between tables with maximum stresses and tables with detailed stresses

stresses in ringsstresses in bends

stresses in straight pipe

totalled stresses principal stresses

check stresses

ring deformations

Maximum stress components per elementalong the pipeline axis

Stress components over circumferenceof one cross section

Maximum values are calculated from144 points over the circumference

of each cross section

Stress components are shown in 48 points over the circumference

of the cross section

37

1

13

25

= (N-1)*7.5 degr.

N

RelationshRelationship ip

between between stress stress tablestables

59

Stress distribution in straight pipe section

Stresses from pipe bending moment [N/mm2]

-7

+7

StressStresses es

from from pipe pipe

bendibending ng

momemomentnt

60

CircumfereCircumferential ntial

normal normal ring stressring stress

Stress distribution in ring section

Circumferential normal ring stress [N/mm2]

-2.5

315

61

CircumfCircumferential erential

wall wall bending bending stressstress

+134

(MGRAPH) Circumferential wall bending ring stresses [N/mm2]

Circumferential inner wall bending stress

Circumferential outer wall bending stress

Axial outer wall bending stress

Axial inner wall bending stress

+134

-134

+40

-40

62

Von Von Mises Mises ring ring

stressstress

Check stress distribution

Von Mises ring stress distribution [N/mm2]

122

63

RRaaddiiaal l ddeeffoorrmmaattiioonn

Radial deformation

Radial deformation [mm]

-7.5

+6.3 +6.3

-5.6

352.5o187.5o

64

Answers to the questionsAnswers to the questions

65

At the beginning of this tutorial two questions were asked:

1. To what extent will the pipeline follow the soil settlement?

The maximum deflection of the pipeline at the middle of the settlement area amounts to 61 mm, whereas the soil settlement is 500 mm.

2. What is the maximum stressing of the pipeline?

The maximum stressing occurs in a cross section near the edge of the settlementarea due to the peak in the bearing soil reaction.The maximum uniaxial circumferential stress amounts to 135 N/mm2, whereas the maximum uniaxial longitudinal stress amounts to 47 N/mm2.The maximum Von Mises stress amounts to 122 N/mm2.

Special screensSpecial screenswarnings tablewarnings table

Click ‘warnings/error’ table

In session 20 (latest) in DF5 warning W500/17 (see Help) was found, saying a largevalue of the spring support was found. This, however, was our intention.

66

Special screens history tableSpecial screens history table

Special screensSpecial screensstatus tablestatus table

The ‘status’ table provides information on the criteria (program version etc.) and options chosen by the user on which the calculations are based and the ‘occurrence’ number of each individual input and output table. This status table is for QA purposes.

Click ‘status’ table

67

Special Special screens screens history history tabletable

Special screensSpecial screenshistory tablehistory table

The ‘history’ table provides a log on the actions performed with a project. The first time a project is established, the history starts within session 1 and each next time the project is started a new session is added. The history table is for archiving purpose on the project.

Click ‘history’ table

68

Special featureSpecial feature table naming table naming

In various screens of this tutorial reference was made to names of tables, e.g. ‘Click table SECTION’ or the name of a stress component SXUB0 was used.These are names that have been used before in the MSDOS version of the programand many users are very familiar with these names, and because they are short, it is an easy reference.In the program screens these names are not shown, but there is a special facilityto show these names. If this feature has been chosen, the short names are shown ahead of the table descriptions. An example is:

‘short names’

.. and before it was:

Table namingTable naming

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‘‘Short names’ facilityShort names’ facility

Click ‘advanced setup’

Click ‘start’ on the roadmap to get the start screen

Activate the radio button ‘as with PLE3’

‘Save & Close’ project

endThank you for your patience

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Documents

Tutorial on Ple 4 edu