RM E Prestressing Basic Part1 EC

7/21/2019 RM E Prestressing Basic Part1 EC

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RM BridgeProfessional Engineering Software for Bridges of all Types

RM Bridge V8i

December 2011

TRAINING PRESTRESSING BASICANALYZER PART 1: EC


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Training Prestressing BasicANALYZERPart 1: EC I

Bentley Systems Austria

Contents

1

General ................................................................................................................... 1-1

1.1

Starting the Program ...................................................................................... 1-1

1.2

Subjects Covered in this Training .................................................................. 1-1

2

General Example Data ........................................................................................... 2-2

2.1

Structural Model ............................................................................................ 2-2

2.2

Cross-Section ................................................................................................. 2-5

2.3

Substructure ................................................................................................... 2-7

2.4

Pre-Stressed Tendon Layout for Internal Tendons ........................................ 2-8

3

Lesson 6: Analyzer ................................................................................................ 3-9

4

Lesson 6: Tendon Definitions .............................................................................. 4-11

4.1 Tendon Material Import ............................................................................... 4-11

4.2 Definition of Tendon Groups ....................................................................... 4-12

4.3 Assign the Tendon Group to the Elements .................................................. 4-13

4.4

Definition of the Cable Geometry ............................................................... 4-14

4.5 Definition of the Tendon Stressing Schedule .............................................. 4-17

5 Lesson 7: Load Management ............................................................................... 5-19

6 Lesson 8: Load Definitions .................................................................................. 6-21

6.1 Definition of Load Cases for Self Weight ................................................... 6-21

6.2 Definition of Load Cases for the Additional Loads ..................................... 6-23

6.3 Definition of Load Cases for Pre-Stressing ................................................. 6-24

6.4 Definition of Load Cases for the Creep and Shrinkage Effects ................... 6-25

7

Lesson 9: Definition of Construction Stage 1 ...................................................... 7-26

7.1

Creation of construction stages .................................................................... 7-26

7.2

First construction stage ................................................................................ 7-27

7.2.1

Activation ................................................................................................. 7-27

7.2.2

Schedule actinscalculations ................................................................. 7-27

8


8.1

Element Activation ........................................................................................ 8-1


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Training Prestressing BasicANALYZERPart 1: EC II


8.2

Calculation (Static) ........................................................................................ 8-1

9


9.1

Element Activation ........................................................................................ 9-2

9.2

Calculation (Static) ........................................................................................ 9-2

10

Lesson 12: Definition of Final Stage (Creep) ...................................................... 10-3

10.1

Calculation (Static) ...................................................................................... 10-3

11 The Calculation .................................................................................................... 11-4

11.1 Calculation options ...................................................................................... 11-4

11.2 Special settings ............................................................................................ 11-5

12

Result presentation ............................................................................................... 12-7

12.1 Possibilities in presentation of results .......................................................... 12-7

12.2 Diagram creation via RM-Sets .................................................................... 12-8


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Training Prestressing BasicANALYZERPart 1: EC 1-1


1 GeneralThe understanding of basic definitions and concepts as given in the Getting Started ex-

ample is assumed in the following example.

The principles shown in the Getting Started example for Modeler and Analyzer:

Defining the structural model

Defining a tendon geometry

Defining loads

Defining a traffic loading case

Defining a construction schedule

Running the calculation

Viewing the results

Fiber stress check

Ultimate load check

Shear capacity check

1.1 Starting the Program

The program installation must be completed before any work can be started. The instal-

lation procedure automatically creates the following icon on the desktop:

To start the program, use the desktop icon or select the icon from the Windows Start

menu atAll Programs, Bentley.

1.2 Subjects Covered in this Training Detail modeling in Modeler (temperature points + pier and support conditions).

Load definition for three construction stages.

Traffic loading case definition in accordance with DIN.

Construction schedule definition for the three construction stages.

Making the structural analysis. Calculation result viewing.

Fiber stress check.

Ultimate load check.

Shear capacity check.


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2 General Example DataIn this example, a three span bridge is presented with a hollow box girder. It is built

span by span in three construction stages.

Figure 2-1: 3D-view of the bridge.

The span widths of the pre-stressed concrete girder are 40m, 60 m and 40m. The heightof the box cross-section is variable along the curved bridge axis.

2.1 Structural Model

40m 60m 40m

10x4m 10x4m15x4m

A4A1 A2 A3

20m

Figure 2-2: Structural model.

System axis: Horizontal plan

1.Part: Straight Line: Station: 0-20 m


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2.Part: Spiral: A=100, RENDE=200m: Station: 20-70 m

3.Part: Circle: R=200: Station: 70-140 m

System axis: Vertical plan1.Part: Line: dXabsolute=65m, dZabsolute= 1.083m Station: 0-65 m

2.Part: Line: dXdifference=75m, dZabsolute= -0.2924m Station: 65-140 m

Rounding with Insert parabola by intersection R=2000m

Pier at A2:Height: 20m (4 Elements each 5m).

Pier at A 3:Height: 20m (4 Elements each 5m).

Numbering system:

Node numbers (span) : 101-111-126-136Element numbers (span) : 101-110,111-125,126-135

Active elements:

Construction Stage 1: 101-113, 1100-1103, 1200-1204

Construction Stage 2: 114-128, 1300-1304

Construction Stage 3: 129-135, 1400-1403


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10x4m

40m 60m 40m

10x4m 10x4m15x4m

A4A1A2

A3

40m

10x4m

A212m

40m 60m

15x4m

A1 A2 A3

Stage 1:

A1

Stage 2:

12m

Stage 3:

113

135

128

Figure 2-3: Construction stages.

Axis 1 Axis 2

1102

X

Z

1101

1402

1401

101-110

Axis 3 Axis 4

111-125 126-135

Figure 2-4: Support definition.


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2.2 Cross-Section

Y

Z

13,0 m

6,5 m 6,5 m

3,00 m 3,00 m

5,0 m

0,20 m

1,50m1,50m

1,0m 1,0m

0,25m

h_cs_tab(sg)

d_bot_tab(sg)d_web_tab(sg)

0,40m

0,90 m

4,0m 4,0m

0,40m12,2 m

0,15 m

1,5m1,5m

2,00 m 2,00 m

Figure 2-5: Main girder cross -section.

Node 0Spring 1100

Node 1101 Spring 1102Spring 1101

Y

Z

AXIS 1

2,40m 2,40m

Node 101

Figure 2-6: Definition of bearings at axis 1.


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Node 0

Spring 1400

Node 1401 Spring 1402Spring 1401

Y

Z

AXIS 4

2,40m 2,40m

Node 136

Figure 2-7: Definition of bearings at axis 4.

1.5m

Y

Z

5.0m

Figure 2-8: Pier cross-section.


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Table 2-1: Spring constants.

Element CX [kN/m] CY [kN/m] CZ [kN/m] CMX [kNm] CMY [kNm] CMZ [kNm]

1100 1e8 1e8 1e8 1e8 1e8 1e81101 1e8 1e8

1102 1e8

1400 1e8 1e8 1e8 1e8 1e8 1e8

1401 1e8 1e8

1402 1e8

2.3 Substructure

seg2

Pier1

0

20m

Segment 1

Connection point

Start of segment 2

Axis 2

Connection point

1202

1203

Eccentric connection of the pierwith the main girder

1204

111 seg1

1201

seg2

Pier1

Figure 2-9: SubstructureAxis 2Pier 1 (Segment2).

0

20m

Segment 1

Connection point

Start of segment 3

Axis 3

Connection point

1302

1303

Eccentric connection of the pierwith the main girder

1304

126 seg1

1301

Seg3

Pier2

Seg3

Pier2

Figure 2-10: SubstructureAxis 2Pier 2 (Segment3).


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2.4 Pre-Stressed Tendon Layout for Internal Tendons

Tendon 101Tendon 102

Tendon 103

Clearance 40cm from top Clearance 40cm from top

Clearance 20cm from bottom Clearance 20cm from bottomClearance 20cm from bottom

12 m16 m

140 m

12 m 18 m12 m

40m 40m60 m

12 m 18 m 12 m

101 123104 108 111 114 118 126 133 135129

16 m12 m

Figure 2-11: Tendon arrangement

span 1: 101 (12 tendons) Ac=16cm2, duct area Ah=50cm

2(Nodes 101-115)


2(Nodes 108-129)


2(Nodes 123-136)


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3 Lesson 6: Analyzer

In the following chapters further inputs for the preparation of the project in Analyzer

will be shown and explained.

Before continue with the inputs it is recommended to recalculate the project the sys-

tem which was exported from the analyzer. This step is necessary because on the one

hand the data is with this checked and on the other hand this is needed for geometry

depended inputs (e.g.: referring to the centre of gravity at the definition of the tendon

geometry).

By clicking the Recalc button in the main input window (Analyzer) a new windowwith recalc options opens. For now only two recalc options should be activated

Cross-section calculation and Structural check. However, it is possible to leave the

default options. In this case there would come a warning that no stage is defined this

is just information that no stage was calculated because no stage (actions) is defined.

Figure 3-1: Recalculation window

After the calculation and refreshing of the 3D View (using free hand symbols or just s

small rotation of the system) also the statical model in the main window is updated (ec-

centricities, element axis, etc). By clicking the right mouse button view options (last

button in the menu) can be defined (f.e. cross-sections, element bodies, tendons, etc).

All structure data defined in Modeler and exported to Analyzer can be seen under Prop-

ertiesor Structurein Analyzer tree menu. Theoretically all these data can be modified.


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However, note that after each export of the data fromModelerto theAnalyzer, the mod-ified structural data (those, coming from Modeler) are overwritten. In this case all the

modifications are lost and have to be done once again if they were not saved by TCL

export. In this case, if the data/modifications were properly saved into TCL, the TCL

can be imported and the data will be overwritten once again. Thats why is for perma-nent changes recommended to edit the structure in Modeler.


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4 Lesson 6: Tendon Definitions

In the following chapter, the definition for the tendons will be done. In Modeler most of

the structure definitions are already done. The only structure definition which is missing

is the specification of the tendons layout and the according stressing procedure.

4.1 Tendon Material Import

To define a tendon correctly a material is needed. All material used in Modeler were

also exported to the Analyzer and are saved to the project database

(PropertiesMaterial). The Tendon material has to be imported manually.

To load the material properties go to Menu File Load Default Properties or to

tree menu Configuration Load Default Properties.

A new window opens.

In this window are the Materials (or Variables) copied from the program database (left

side of the window) to the project database (right side). There are different material

groups from which a certain material can be selected and copied to the project database.

Multiple selection of material is possible by using the space button.

Select appropriate material for pre-stressing (as it is shown in the figure below).


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Figure 4-1: Load default propertiesimporting material to the project database.

4.2 Definition of Tendon Groups

The tendon geometry will be simplified so that all the tendons practically positioned in

the webs will grouped together and located in the middle of the cross-section. At that

principle and due to the three construction stages only three tendons have to be defined.

Further simplification will be done based on the fact that the tendons overlap each other

on some intervals. Thats why only one tendon geometry (master tendon) have to be

defined with the full 3D geometry over the whole length of the structure. Then the indi-

vidual tendon groups can be defined using the geometry of the master tendon. These

tendon groups are called slave tendons.

This procedure will be used mainly for preliminary designs where the tendon geometry

has to be designed. The advantage is that you can change the geometry of all tendon

groups by changing only the master tendon.


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Open the list for the definition of tendons under Structure Tendons Ele-

ment Assignment.

Select the insert after button to open the input window for master ten-don and tendon group definition.

Input the data as shown in the table below.

Definition of

Tendon Groups

Structure Type Type - internal Type - internal Type - internal Type - internal

Tendongeometry

Master profile Slave profile Slave profile Slave profile

TendonsOrginal

Geometry- 1 1 1

TndNum 1 101 102 103

Element Assign-

mentMaterial

EN_Eurocode:

Strand-1640/1860

EN_Eurocode:

Strand-1640/1860

EN_Eurocode:

Strand-1640/1860

EN_Eurocode:

Strand-1640/1860

Top Table Number 1 12 18 12

At [m2] 0.0016 0.0016 0.0016 0.0016

Ad [m2] 0.0050 0.0050 0.0050 0.0050

Beta

[Deg/m]0.151 0.151 0.151 0.151

Friction 0.25 0.25 0.25 0.25

Descrip-

tionMaster cable

Prestressing

cable 101

Prestressing

cable 102

Prestressing

cable 103

Note: More detailed information about the individual entries in the input window can be found by cal l-

ing the program help (F1).

4.3 Assign the Tendon Group to the Elements

Now the elements have to be assigned to the tendons. By this action the program gets

the information through which elements the tendon goes.

Select the insert after button in the lower table to open the input window

The tendon groups are listed in the upper table and the elements to be assigned to the

selected tendon are displayed in the lower table.

Input the data using the information shown in the table below.

Input the Cable As-

signment

STRUCTURE TdNum 1 101 102 103

El from 101 101 108 123

TENDON DATA El to 135 113 128 135

El step 1 1 1 1

EL. ASSIGNMENT

Bottom table


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4.4 Definition of the Cable GeometryNow the actual geometry of the tendon will be defined. As already mentioned above, in

this example will be only the geometry of the master tendon defined. The salve tendons

will have the same geometry as the master tendon due to the definition above (slave

tendons with a reference to the master tendon).

Activate the master tendon in the upper list to start the definitions of the ten-

don geometry.

Select the info button between the upper and lower list.

The input window for the graphical tendon geometry definition will be opened. Please

note that the graphical screen will be empty if you havent recalculated the cross-

sections and the structure before. However, in this window the preview can be changed

between different views (CS view, elevation, plan, isometric and side elevation) where

can be graphically seen the defined input.

Figure 4-2: Tendon geometry input window with graphical overview.


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Click the insert after button on the left bottom side of the screen to activate the

input field.

Define the tendon positions as it is shown in the table below.

The input for one tendon position is confirmed by clicking on the APPLY but-

ton.

Input the Cable

Geometry

STRUCTURE TdNum 1

Ref. Elem. 101 104 108 111 114

TENDON DATA CS pnt - SP-B - SP-T -

X/L 0 0 0 0 0

GEOMETRY eY[m] 0 0.2 0 -0.4 0

eZ[m] 0 0 0 0 0

Bottom table Rel. to Elem CS pnt Elem CS pnt Elem

Alfa1 Free Value Free Value Free

Value - 0 - 0 -

Alfa2 Free Value Free Value Free

Value - 0 - 0 -

Rel. to Elem Node Elem Node Elem

Extern

TdNum 1

Ref. Elem. 118 123 126 133 135

CS pnt SP-B - SP-T SP-B -

X/L 0.5 0 0 0 1

eY[m] 0.2 0 -0.4 0.2 0

eZ[m] 0 0 0 0 0

Rel. to CS pnt Elem CS pnt CS pnt Elem

Alfa1 Value Free Value Value Free

Value 0 - 0 0 -

Alfa2 Value Free Value Value Free

Value 0 - 0 0 -

Rel. to Node Elem Node Node Elem

Extern

The tendon definition for the master tendon is now completed and will be displayed in

the main graphic screen after calling redraw (freehand symbol V) or by rotating of the

system. The tendon profile is drawn in a turquoise color.

Note: More detailed information about the individual entries in the input window can be found by cal l-ing the program help (F1).

The different ways of referring are shown more detailed in the figures below.


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CG

NODE

RP

Tendon position

CG

NODE

RP

Tendon position

CG

NODE

RP

Tendon position

ez e

y

ey

ez

ez

ey

Figure 4-3: Different references for the tendon positionsame tendon position but different eccentricities

and different reference points.

Figure 4-4: Different references for the angle Alpha1 the same applies for


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Note: The reference point has to be created in Modeler (or even in Analyzer) and the Reference-Set hasto be of type Geometry Point or Stress Check Point.

The reference point itself can also vary along the bridge axis. And this possibility can be used to

define the tendon geometrysometimes it is the best approach. In the Analayzer there the tendon

has to be created and at the geometry definition the only thing that has to be defined is that the

tendon is in all elements relative to the reference point (with or without any eccentricity).

With finished tendon geometry definition of the master tendon also the geometry of the

slave tendons is defined the reference to the master tendon was defined and the ele-

ments were also assigned already.

To see the all tendons in the general 3D view the project has to be calculated at the

same principle as before starting with the tendon geometry definition (recalculation of

the cross-sections and structure check).

4.5 Definition of the Tendon Stressing Schedule

The tendon stressing actions are not defined in the stage directly but are defined sepa-

rately and are afterwards referenced. The tendon stressing procedure is defined under

Tendon Actions.

Select ScheduleStages Tendon Actions to start the stressing definitions.

All the actions that are applied to the tendons are defined in the two tables in this win-

dow. The top table lists all the actions applied to the tendons. The bottom table displays

details of the action for one tendon that is selected in the top table.In this window all the actions (pre-stressing, wedge slip, relaxation, etc) for certain ten-

don (group) are defined.

The Tendon 101 is stressed in the first construction sequence and can be stressed from

both sides. The Tendon 102 and 103 are stressed in the subsequent construction stages

stage 2 and stage 3. Due to practical capabilities of pre-stressing, these two cable can be

stressed only from the right side.

Note: The left and right side of the tendon is defined by the tendon orientationx coor-

dinates. The left side is there where the tendons stars and the right side is there where

the tendon endsor in another words XL < XR.

The stressing of the tendon can be defined by a force or by a factor, whereby the factor

references to the maximum allowable force in the tendon defined in the assigned ma-

terial (PropertiesMaterial).

Each tendon will be firstly for 5% overstressed and after this a wedge slip of 6 mm hap-

pens and so the stresses in the tendon are under the maximal allowable stress/force.

Define the tendon stressing actions as is shown in the tables below.


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Input the TendonSchedule

SCHEDULE. STRESS/RELAX/WEDGE

PREL

WEDL

PRER

WEDRType FACT. - FACT. -

STAGES TENDON 101 101 101 101

Factor / Wedge [m] 1.05 0.006 1.05 0.006

TENDON ACT: Stress label STG1 STG 1 STG 1 STG 1

Top table

STRESS/RELAX/WEDGE PRER WEDR PRER WEDR

Type FACT. - FACT. -

TENDON 102 102 103 103

Factor / Wedge [m] 1.05 0.006 1.05 0.006

Stress label STG2 STG2 STG3 STG3

The stress label has to be defined for referencing to it (and so to the corresponding ten-

don actions) by the construction sequence definition.

By clicking the info button the stresses (and forces) in the tendon (selected by the

action) and up to the selected stressing action are graphically displayed.

Figure 4-5: Diagram of stresses and forces in the tendon after corresponding stressing action.


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5 Lesson 7: Load Management

Load Management (Schedule Load Definition Load Management) is used for

automatic summation of permanent loads whereby certain load cases (loads) are (can

be) grouped together. For example the self weight from each construction sequences is

summed up to one load case (SW-SUM = SW-STG1 + SW-STG2 + SW-STGn).

In total the main capability of the load management is:

An individual loading case can be defined so that, after calculation, its resultsare automatically added to 1, 2 or 3 other load cases.

An individual loading case can be defined so that, after calculation, its resultsare automatically combined into 1, 2 or 3 envelopes.

Loading cases and envelopes defined in Load Management are set up (initialized;

created) using the LcInit function. Instead of using the LcInit function an automaticinitialization of the Load Management load cases can be done by activating the check

box Init Load Manager in the Recalc pad.

Define the Load Management as it is shown in the table below.

Input for the Load

Manager

Schedule Load Manag. SW SDL PT CS

Load case I SW-SUM SDL-SUM PT-SUM CS-SUMLoad Definition State Total Total Total Total

Load case II STG-SUM STG--SUM STG-SUM STG-SUM

Load Management State Total Total Total Total

Load case III - - - -

Top table State - - - -

Envelope I - - - -

Comb I - - - -

Envelope II - - - -

Comb II - - - -

Envelope III - - - -

Comb III - - - -

The load management can be also created by loading the appropriate load manager tem-

plate from Menu (Extras Loading and Stages Load Management Definitions

(English). The Load Manager for traveler load (TR), wet concrete load (WC) incremen-

tal launching method (ILM) and for cable loads (CABLE) can be deleted or ignored.

The final creep loading case is CS-SUM should not be added to the general loading case

as it is necessary to have the final creep and shrinkage effects separate so that the struc-


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ture can be checked after construction (before final creep and shrinkage) with live load-ing and other loading combinations and at the time infinity with live loading and other

combination.


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6 Lesson 8: Load Definitions

Loads are defined by Load Cases or by Load Sets ( Schedule Load Definition

Load Case Definition or Load Set Definition). Several loads can be combined into

one Load Case or also in one Load Set.

Load Set cannot be calculated directly and thats why they have to be assigned to the

Load Case. One Load Set can be assigned to different Load Cases. It is also possible to

define a different multiplication factor for the loads defined in the Load Set.

With creating a load case the defined load is not calculated. The load is calculated with

the calc action in the schedule actions.

In this example the loads will be defined only in the load cases.

6.1 Definition of Load Cases for Self Weight

The bridge is build in three construction stages and thats why also three separate self

weight load cases have to be created and each of them has to be calculated in corres-

ponding stage.

Change into Schedule Load Definition Load Case DefinitionTop Table

The window is split into two lists. At the top the load cases are listed and in the bottomlist the defined loads for the selected load case are listed.

Define the self weight load cases as is shown in the table below.

Definition of LoadCases

Schedule Name SW-STG1 SW-STG2 SW-STG3

Type Permanent Permanent Permanent

Load CaseDefini-

tionLoad Manag. SW SW SW

DescriptionSelf weight 1st

construction

stage

Self weight 2ndconstruction

stage

Self weight 3rdconstruction

stage

Top table

The type of the load case (Duration type: Permanent or Non-Permanent) defines if the

load is permanent or notwill it be considered in the calculation of creep and shrinkage

effects or not.

The input Load Manag. establishes the connection to the Load Manager. At that

principle now all the results due to the self weight loads (SW-STG1, SW-STG2 and


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SW-STG3) will be saved/copied (superposed) to two load cases defined in the loadmanagerSW-SUM and STG-SUM.

The load cases were created and now actual loads have to be defined.

Change into Schedule Load Definition Load Case Definition Bottom

Table

The load type to be used in this example is Self weig just as load or Self

weightload and mass

Definition of LoadCases

Schedule. Number SW-STG1 SW-STG2 SW-STG3

Loading

Uni-

form load

Uni-

form load

Uni-

form load

Uni-

form load

Uni-

form loadLoad Case Defini-

tionType

Self

weight

Self

weight

Self

weight

Self

weight

Self

weight

From 101 1201 114 1301 129

Bottom table To 113 1204 128 1304 135

Step 1 1 1 1 1

Rx 0 0 0 0 0

Ry -1 -1 -1 -1 -1

Rz 0 0 0 0 0

Gam

[kN/m3]0 0 0 0 0

If gamma is set to 0 then the specific weight used in the calculation of the self weight istaken from the one assigned to the element via the assigned material (see Structure

Elements Material or Properties Material data). If the values is defined (and is

unequal zero) then this values is taken as specific weight and used in the calculations.

In the load cases SW-STG1 and SW-STG2 also the self weight of the piers has to be

defined.

Note: For faster and easier definition of the load cases it would be possible to defined first one load case

and the load for it. Afterwards, the subsequent load cases could be created by copying, renaming

and renumbering of the first load case.

Another approach would be: First to create one load case (top table) and activate the option

Load only elements, activated in current stage and then in the definition of the load (bottom ta-ble) define/load all elements (stepwise: 101-135, 1201-1204 and 1301-1304; or at once: 101-1304) with the same load type. Afterwards that load case has to be copied twice (the total number

of the load cases has to be the same as the number of the construction stages in our case this

means three).

For detailed load description use program help (F1) or the Appendix where all load types areexplained.


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6.2 Definition of Load Cases for the Additional LoadsIn this example three different superimposed dead loads (left concrete barrier, right con-

crete barrier and road weigh) will be created and calculated. All of them will be defined

in one load case.

Also these loads have to be taken into account for the creep and shrinkage calculation

and have to be thats why set to permanent.

Insert Load Set

Schedule Name SDL

Type Permanent

Load Case Defini-

tion

Load Manag. SDL

Top table

Define Load Sets forthe Additional Loads

Schedule Number SDL SDL SDL

Loading Uniform load Uniform load Uniform load

Load Case Defini-

tionType

Uniform con-

centric elementload

Uniform eccen-

tric element load

Uniform eccen-

tric element load

From 101 101 101

Bottom table To 135 135 135

Step 1 1 1

Qx [kN/m] 0 0 0

Qy [kN/m] -35 -6.1 -6.1

Qz [kN/m] 0 0 0

Direction Global Global Global

Eccentricity -Local+Z

Elem-Ecc

Local+Z

Elem-Ecc

Ey [m] - 0 0

Ez [m] - +6.3 -6.3

Load applica-

tionReal length Real length Real length

DefinitionLoad/Unit

length

Load/Unitlength

Load/Unitlength

At the creation of the load case the link to the load management was defined at the same

principle as for the self weight load cases.

The Z-Element eccentricity defines the eccentricity length (in the Z-direction - transver-

sal) between the element/cross-section gravity centre to the node. At that principle it is

possible to define the eccentricity relative to the node (same applies for the definition of

the horizontal load). In our case there will be no difference due to the cross-sections

symmetry.


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Ez

CG

Figure 6-1: Local Y-Element eccentricity.

6.3 Definition of Load Cases for Pre-Stressing

For now only the tendon geometry and tendon stressing procedure was defined. To ap-

ply the load on the structure load cases have to be defined also. Define the load cases as

it is shown in the table below.

Insert Load Set

Schedule Name PT-STG1 PT-STG2 PT-SRG3

Type Permanent Permanent Permanent

Load Case Defini-

tionLoad Manager. PT PT PT

Top table

Define Load Sets forthe Tendons

Schedule Number PT-STG1 PT-STG2 PT-STG3

Loading Stressing Stressing Stressing

Load Case Defini-tion

TypeTendon stress-

ingTendon stress-

ingTendon stress-

ing

From 101 102 103

Bottom table To 101 102 103

Step 1 1 1

TypeIncrement

Force

Increment

Force

Increment

Force

The selection of the type of stressing (Incremental-Force or Total-Force) has effect only

if multi-stage stressing procedure is defined. It must be defined whether the total stress-ing force of a stress level has to be applied or only the differential force when compared

to a previously applied stress group (for more information see the RM Analysis user

guide chapter 11.5.3).


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6.4 Definition of Load Cases for the Creep and Shrinkage Ef-fects

Insert Load Case

Schedule Number CS-STG1 CS-STG2 CS-STG3 CS-INF

Type Permanent Permanent Permanent Permanent

Load Case Defini-

tionLoad Info CS CS CS -

Top table

Load cases for calculation of creep and shrinkage effects have to be just created noload definition (in the bottom table) has to be defined.

The definition of the load cases is done only because of the load management and post-

processingthe results of the calculation of the time effects (done by the creep action)

are saved to these load cases and accordingly to the load cases defined in load manage-

ment.

The creep and shrinkage load cases are linked to the load management at the same prin-

ciple as other load cases definition of the load management label/input (CS). Du to

that definition and the definition of the load management the creep and shrinkage results

are saved/copied to the CS-SUM load case and added to the STG-SUM load case.

The final creep and shrinkage effect (at time infinite CS-INF) are saved only to thatload case because there is no load management label defined for this load case. This has

to be done due to the combinations where different factors are used for time effects at

time 0 and time infinite.


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7 Lesson 9: Definition of Construction Stage 1

The definition of the required definitions (structure including tendons, load cases and

tendon stressing procedure) for the construction sequence calculation is finished and the

definitions for the construction sequence calculation can start.

This definition is done underScheduleStages Activation orSchedule Actions.

In the top table a construction stage is created (and listed) and some basic definitions are

defined. The bottom table changes between theActivationsand Schedule Actions.

In the Activation table it is defined which elements are activated in the corresponding(construction) stagethe active elements becomes a part of active structural system and

can be loaded and included in the calculation.

In the Schedule Actions table it is defined which actions (static calculations, dynamic

calculations, plot actions, design actions, list actions, etc.) should be made in the corres-

ponding (construction) stage.

Construction stages have a time start and duration.

7.1 Creation of construction stages

Change to

Schedule

Stages

Activation Top table

Select the append button to open the input window for the construction stage

definition. Insert the construction stage named STG1 and the description

Construction Stage 1 here.

Use the same principle to add also other stages (as is shown in the table below)

Input Active Elements

to Stage 1

Schedule Name STG1 STG2 STG3 STG-FIN

DescriptionFirst con-struction

stage

Secondconstruction

stage

Thirdconstruction

stage

Final con-struction

stage

Stages

Activation

Bottom table


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7.2 First construction stage

7.2.1 Activation

Change to ScheduleStagesActivation Bottom table

Select the append button to open the input window for element activation

Activate the elements as is shown in the table below.

Input Active Elementsfor Stage 1

Schedule Activate

Deactivate

Stages From 101 1201 1100 1200

To 113 1204 1102 1200

Activation Step 1 1 1 1

Age 14 42 0 0

Bottom table ts 0 0 0 0

Agedefines the ageof concrete when it is activated for the first time (becomes a part

of the structural system) and will be considered by the calculation of creep and shrin-

kage effects. The input tsdefines the time (after pouring the concrete) when shrin-

kage starts.

The spring elements have to be also activatedthey are representing the support condi-

tions.

7.2.2 Schedu le actins calculat ions

Input the Calcu-

lation (Static)

for Stage 1

Schedule ActionCalcu-

lation

(Static)

Calcu-lation

(Static)

Calcu-lation

(Static)

Calcu-lation

(Static)

Calcu-lation

(Static)

Loadcase

action

Type Calc Stress Calc GROUT Creep LcInit

StagesInp1

SW-STG1

- PT-STG1 - 1STG-SUM

Inp2 - STG1 - STG1 - -

Inp3 - - - - -

Schedule Actions Out1 - - - - CS-STG1STG1-

SUM

Out2 * * * - * -

Bottom table Delta-T 0 0 0 0 28 -

Calc is the actions which calculates a normal load case

Stressconverts the tendon forces, defined through the definition of the tendon stressing

actions, into loads whereby the corresponding elements are loaded. However, these

loads are not calculated jetthey are just converted.

These forces (pre-stressing effects) are calculated (applied on the structure) by the Calc

action which is the subsequent action, whereby the reference to the corresponding pre-


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stressing load casehas to be definedStress Label STG1 and the Load Case PT-STG1are referencing to the same tendon.

Groutaction simulates grouting of tendon ducts and with this action the composite be-

haviour between the concrete elements (cross-section) and tendon is established (strain

in the tendon is equal to the strain of the corresponding elements).

Hereby also the cross-section values changes and these changes can be in the calcula-

tion properly taken into account. This is done by the definition of the recalculation op-

tions defined in the recalc pad (- duct areas, + tendon areas, - grouted areas). The new

cross-sections values are used in the global calculation and are also saved to the corres-

ponding list file (cross.lst).

With Creepaction the time effects are calculatedcreep and shrinkage of concrete andrelaxation of tendons. The corresponding functions for the calculation are predefined

(and can be modified) under Properties Variables and are assigned to the materials

under Properties Material Data. The time effects can be also graphically displayed

underResults Plot Creep/Shrinkage Curves.

Delta-T defines how long a certain system is exposed to the time effects time to the

next structural change or when an additional permanent load is added. The Number of

time steps (Input-1) defines in how many calculation intervals the howl time interval

(Delta-T) is subdivided, whereby it is possible that the subdivision step is linear or loga-

rithmic (Recalculation pad C+S). For smaller time intervals it is recommended to

use 1 time step and for longer time interval (for time infinitefinal creep) 3 to 5time (logarithmic) time steps. Each time step is saved to a separate load case and the

total effect is saved to the predefined dummy load case (Output-4).

For the calculation of relaxation (Include Steel relaxation recalculation option) the

summation load case has to be defined in the recalculation window (pad). This has to be

done to define which (permanent) loads have to be considered in the calculation.

With the Action LcInit (Load case In i tialization) certain load case can be copied or an

empty load case is created if there is no load case defined in the Input-1empty load

case is created (initialized).

In this example the summation load case (STG-SUM) is copied to a new one (STG1-

SUM) at the end of the construction stage. At that time are in the summation load case

all (calculated) loads from the first construction stage summarized (SW-STG1+PT-

STG1+CS-STG1) due to the definitions in load management. To see the results of the

loads in the first construction stage only, this has to be done, due to the automatic add-

ing of the results from the subsequent calculations, which will be defined in the second

construction stage.

The results of each calculation action are additionally saved also to a list file defined in

each action separately (definition of the Output-2).


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8 Lesson 10: Definition of Construction Stage 2At the same principle also the activation and schedule actions in the second and third

construction stage have to be defined. Due to the analogy of the schedule actions the

howl construction stage could be copied and the definition accordingly modified. The

activations are not copied and have to be additionally defined accordingly to the active

system in the second construction stage.

Another way to define subsequent construction stages is to define (copy and modify)

them via TCL (here the data is exported, copied, modified and afterwards imported).

8.1 Element Activation

Input Active Elements

to Stage 2

Schedule Activate

Deactivate

Stages From 114 1300 1301

To 128 1300 1304

Activation Step 1 1 1

Age 14 0 42

Bottom table ts 0 0 0

8.2 Calculation (Static)

Input the Calculation(Static) for

Stage 2

Schedule ActionCalculation

(Static)

Calculation

(Static)

Calculation

(Static)

Calculation

(Static)

Type Calc Stress Calc GROUT

Stages Inp1 SW-STG2 - PT-STG2 STG2

Inp2 - STG2 - -

Inp3 - - -

Schedule Actions Out1 - - - -

Out2 * * * -

Bottom table Delta-T 0 0 0 0

ActionCalculation

(Static)Load case

action

Type Creep LcInit

Inp1 - STG-SUM

Inp2 1 -

Inp3 -

Out1 CS-STG2 STG2-SUM

Out2 - -

Delta-T 28 -


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9 Lesson 11: Definition of Construction Stage 3

9.1 Element Activation

Input Active Elementsto Stage 3

Schedule Activate

Deactivate

Stages From 129 1400

To 135 1402

Activation Step 1 1

Age 14 0

Bottom table ts 0 0


Input the Calculation

(Static) forStage 2


(Static)

Calculation

(Static)

Calculation

(Static)

Calculation

(Static)

Type Calc Stress Calc GROUT

Stages Inp1 SW-STG3 - PT- STG3 STG3

Inp2 - STG3 - -

Inp3 - - -

Schedule Actions Out1 - - - -

Out2 * * * -

Bottom table Delta-T 0 0 0 0

ActionCalculation

(Static)

Load case

action

Type Creep LcInit

Inp1 - STG-SUM

Inp2 1 -

Inp3 -

Out1 CS- STG3 STG3-SUM

Out2 - -

Delta-T 21 -


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10 Lesson 12: Definition of Final Stage (Creep)

With the last construction stage the final state of the bridge will be simulated.

For this the super imposed dead loads will be applied on the structure and final time

effects will be calculatedt= (Delta-T=10000 days).

No additional element activation is necessary because the entire system is already act i-

vated.


Input the Calcula-

tion (Static) forthe Final Stage


(Static)

Load caseaction

Load caseaction

Load caseaction

Type Calc Creep LcInit LcAddLc

Stages Inp1 SDL - STG-SUM CS-INF

Inp2 - 5 -STG-INF-

SUM

Inp3 - - - -

Schedule Actions Out1 - CS-INFSTG-INF-

SUM-

Out2 * * - -

Bottom table Delta-T - 10000 - -

In this stage first the superimposed dead loads are applied on the structure and then the

final time effects are calculated.

Because at the end two final load cases are needed including all construction e ffects

(loads) with and without final time effects. To have them two additional actions have to

be defined. After the calculation of the SDL loads the summation load cases is updated

(the SDL results are added to the STG-SUM load case) due to the definition of the load

management. After the Creepaction the summation load case (STG-SUM) is not up-

dated due to the definition of the CS-INF load casethe load case was not linked to

load management. Thats why first the summation load case is copied (LcInit actions)

and then the final time effects (CS-INF) are manually added (LcAddLc) to the copiedload case (STG-INF-SUM).


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11 The CalculationThe construction stage definition is finished now and the first calculation can be done.

Click on theRecalcbutton .

Figure 11-1: Recalc pad.

11.1 Calculation options

Cross-section calculationCross-sections have to be calculated at least once. Hereby the file cross.lst is automati-

cally created. If the cross-section doesnt change(and were once already calculated) thisstep can be skipped.

Structure check

This calculation options checks the structure, deactivates all elements, initializes the

result database and creates a number of list files (material.lst, stress.lst, struct.lst and

tendon.lst)


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If the system doesnt change also this option can be, in certain circumstances, skipped

in additional calculations (the calculation of the construction stages was done and all

stages are skipped; in this case also the optionInit Load Manger has to be turned off).

Note that the envelope files (*.sup) are saved to the main directory (and not the

sub-directoryDefaultSchedule) and are not automatically initialized (only by the SupI-

nit action in the schedule actions). The same fallows for the list (*.list), plot (*.pl and*.pla) and influence (*infl) files which are create/overwritten by the calculation.

With the action GoDel (Group System commands) it is possible to delete the corres-

ponding files in the main working directory as same as in the sub directory. This is rec-

ommended to do to ensure that no files from previous calculations remain.

Stage Calculation

Activation and calculation of the schedule actions in the constructions stages is done.

Influence-lines calculation

Influence lines have to be calculated at least once to make a live load calculation. If the

influence lines data exists (*.infl) and the structure or lane definition was not changed,

this options can be skipped for additional calculations.

Note: For now this option is not needed jet but can be activated.

Time Effects (C+S+Rel.)

To calculate the time effects this option has to be activated, irrespective that creep ac-

tions in schedule actions are defined. This allows making fast calculations, without in-

cluding time effects, very easily.

Include Steel Relexation

The relaxation of pre-stressing steel is also calculated at the calculation of creep and

shrinkage if this option is activated and the summation load case is defined.

Init Load Manager

Before starting with the calculation of the stages all load cases and envelopes defined in

load management are initialized (created).

11.2 Special settingsCross-section correction

This option activates the calculation of the new cross-section values due to the tendons

in it as it explained in7.2.2.

SumLC (summation load case)

Definition of the summation load cases of permanent loads, which is used for different

calculations (Steel relaxation, camber calculation, etc).


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It is used also as a Initial Strain load case if the input of certain standard depended de-

sign checks (seePre-Stressing Training ExampleAnalyzer Part II) references to it.

Calculation

By clicking on theRecalcbutton (in the recalc pad) the recalculation of the active sche-

dule starts. By clicking on theRecalc allbutton all schedule variants will be successive-

ly calculated depending on the defined sequence.

Note: Schedule variants can be defined under Schedule Schedule Variants. Here it is possible to

define different construction variants (construction schedules) at the same system and in the same

project (folder) whereby each variant is saved to its own subfolder.

The calculation status can be seen in the lower windows when the calculation is run-

ning. The status shows which stage, which action and which calculation steps are cur-rently calculated. If in the schedule also plot actions are defined, then the generated

plots are displayed in the main window (4 at once) also.

A calculation protocol is created (recalc.log) and saved to theDefaultSchedule (if more

schedules are calculated the protocol is saved to the corresponding folder) as text file. Ii

is possible to open in from there or by clicking the corresponding button in the program

itself.

During the calculation warnings and errors can occur. The warnings are displayed at the

end of the calculation (e.g.: WARNING: System important files(s) cross.lst cannot be

deleted!)and should be interpreted as hints which should be checked. On the other hand

the calculation is aborted automatically if the definition is incorrect (the calculationcant proceed)ERROR (e.g.: in the schedule actions a load case wants to be calcu-

lated but wasnt created; or the name of the created and calculated load case isnt the

same; in this case the calculation is aborted and an error is displayed; ERROR: Load

case name of the LC does not exist.). Where the calculation stopped can be also seen

in the schedule actions listthose stages (top list) and actions (bottom list) which were

calculated have an OKin the status column.

A running calculation can be aborted also by the user by clicking on the ESC button.

The calculations starts (depending on the calculation options) with the calculation of the

cross-section values and structure control and then the initialization of load manger

(load cases) is done. Thereafter the construction sequence calculation starts where thestages are consecutive calculated, whereby at begin of each stage first the elements are

activated and then each stage action is calculated.


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12 Result presentationIn RM Bridge there is possible to represents the results at different ways. Some of them

are more detailed explained below.

12.1 Possibilities in presentation of results

One of the possibilities to see the results is via Results Load Cases / Envelopes

(Influence lines, etc). Here certain result presentation options have to be defined:

Load case / Envelope; Element Group (if created); Result component (Displacements,

Forces, Stresses); etc. Once this is defined is possible to export the results to a list file

(Print) or to make a diagram (Diagram). By clicking on the Diagram button a new win-

dow opens where additional definitions have to done and once also this is finished the

diagram is created by clicking on the OK button.

Another possibility (with the same approach as above) to create a digram is by the defi-

nition of so calledRmSets. This approach will be more detailed explained in next chap-

ter.

The post processing can be done also with Plot Containers which are created under

Results Plot Conatiners and have to be plotted by the DoPLot actions in schedule

actions. Here not only results can be displayed but the structure itself also. The ap-

proach allows completely free design of the graphical output. The predefined Macros

facilitate the rapid generation (for more information see the RM Analysis User Guide

chapter 8.4.2).

Many predefined plots (e.g.: tendon scheme, tendon geometry, cross-sections, materialdiagrams, creep and shrinkage diagrams, load sets, etc) can be referenced directly in

schedule actions (List/Plot Actions) and plotted by recalculation of the project or only

by this actions (clickRun actionon the left side between the top and bottom list).

A comprehensive presentation (output) of structural data via cad files (DGN or DWG)

is possible withinDraw Manager(ExtrasRM Draw Manager).

Reports can be created within TDF-Reports (File Reports (TDF) Create/Edit

Structure).

An overview of schedule actions defined in each stage can be done by the HTML Stage

Viewer (Extras HTMLStage Viewer).


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12.2 Diagram creation via RM-Sets

Go to PropertiesRM-Sets Top table(list)

Click on the insert after button and define a name of RM-Set. It is possible to de-

fine the description also which will be seen in the created diagram. The type of

RM-Set is Result representation (RESULT).

Figure 12-1: New RM-Set.

After confirming the input by clicking on the OK button the window for the de-

finition of the diagram is opened by clicking on the i button.

Here are several tabs for the definition of the diagram. There are two tabs for the gener-al definitions (scale, paper size, paper orientation, etc) and three other for different re-

sult presentations:

Load Case results

Envelope results

Reinforcement

Normally the correct definition of a diagram (RM-Sets) has to include the definition of

the elements for which the results should be represented and what results should be

represented which includes

definition of the load case / envelope / reinforcement

definition of the result component (bending moment, normal force, shear

force, etc.) / leading superposition value (MinMz, MaxMz, MinQy,

MaxQ, MinNx, MaxNx, etc) and a result component / attribute set

If different result components are defined in one RM-Set the program will automatically

create more diagrams. Same fallows also for the different types of reinforcements

(Attribute Sets)


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Change to the tab Elements.

Define the elements for which the results should be displayed as is shown in the

pictures below.

Figure 12-2: Definition of elements for which the diagram should be shown.

The approach used above uses the predefined element groups which were created al-

ready in modeler (they could be also created/modified in Analyzer). The sane could be

achieved on a different way which is shown in the picture belowhere the elements are

selected by the definition of an element series.

1. Type of referencing to elements

2. Definition of elements

3. Confirming the input


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Figure 12-3: Definition of elements for which the diagram should be shown.

Change to the tab Load Cases.

Define the Load case for which the results should be displayed as is shown in

the picture below. Parallel also the results component is defined.


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It would be possible to add (Insert after) for the same result component different load

cases or for the same load case different result component. Of course, a mixture of both

is also possible. In this case more diagrams would be created.

If the stresses should be displayed, it has to be defined where in the cross-section thestresses should be represented/calculated. This is done by the definition of additional

results parameters (dashed square)for stresses the stress point has to be chosen addi-

tionally.

The diagram can be displayed by clicking on the Plot to file button. The same data

can be exported also to list file (Report file) or to MS Excel (Write to XLS).

The definition of the RM-Set is confirmed by clicking on Save.

The created RM-Set/Diagram can be also seen under Results Plot RM-Sets.

1. Choosing of an Load Case

2. Definition of a result component

3. Confirming the input


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The diagram can be also plotted in the default schedule. This is done via DgmSet action.

At that principle it is possible to plot more diagrams with one RM-Set. As it was already

explained, the summation load case is after each calculation updated. Referring to it

within an RM-Set and plotting the RM-Set using the DgmSet action at different times

will produce different diagrams. But the name of the output file (plot file), defined inthe DgmSet action, has to be different (if not the diagrams are overwritten).

The plot files created at that principle are saved to the (DefaultSchedule). A fast access

to this directory is also possible under Results Plot Directory (DefaultSche-

dule).

Documents

RM E Prestressing Basic Part1 EC