General Workflow Bridge Design

Project Work - Step by Step

The general workflow sequence inside SOFiSTiK using SSD and SOFiPLUS is recommended as follows:

  1. Prepare all project data for input into the software

  2. Create a new SSD project file

    • Define project name

    • Select design code

    • Select system

  3. Define materials

  4. Define standard cross sections

  5. Define prestressing systems

  6. Create Actions

  7. System and load generation within SOFiPLUS

    • Define a bridge axis

      • Define horizontal alignment

      • Define vertical alignment

      • Define placements

      • Define secondary axis if necessary

      • Define variables for cross sections

    • Define bridge cross sections with the Cross Section Editor inside SOFiPLUS

    • Define bridge geometry using the predefined axis geometry

    • Define tendon geometry and tendons

    • Define actions and load cases with Loadcase Manager

    • Define all loads such as additional dead weight, settlement and temperature loads

    • Mesh system

  8. Linear Analysis of already defined loads

  9. Generate envelopes from traffic loads with SSD Task “Traffic Loader”

  10. Define construction stages and start automatic analysis within CSM

  11. Define combinations and superpositions with CSM DESI

    • Intermediate Superpositioning (all variable actions/ loadcases) of inner forces related to the total cross section (final stage).

    • Final-Superpositioning (Dead load, superimposed dead load, prestress, creep & shrinkage & relaxation, envelopes of variable loads) of inner forces related to the partial cross sections.

  12. Design Code Checks

    • ULS Design for required reinforcement, bearing capacity calculation and other ultimate cases.

    • SLS Design: Serviceability checks (fibre stress checks, crack width check, displacements of the structure, fatigue, dynamics etc.)

  13. Generate Report

  14. Save project files

For practical examples and further information about the detailed input please see the available bridge tutorials.

Start a New SSD Project

Important

This is a general description, which can be different from the project discussed in this tutorial. Please make the necessary adjustments by yourself.

Title: Create a New SSD Project | Quality: 1080p HD | Captions: English

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We recommend to use a local directory for your project files to speed up communication between program and database. Later on you can zip and save your project data on a company server.

If you leave the System Information dialogue with OK the selected code is fixed and saved inside the database. You may NOT change the code later on within this dialogue.

../../_images/system-information-01.png

For bridge design we recommend to use a 3D system.

Material Definition

Important

This is a general description, which can be different from the project discussed in specific tutorial. Please make the necessary adjustments by yourself.

Inside the SSD task-tree the task Materials is one of the default settings.

../../_images/material_tree.png

Simply use the right mouse click e.g. New Material from Design Code to generate a new material. You may repeat this command as many times as necessary.

../../_images/materials-01.png

Note

In case you have different construction stages in your cross section (e.g. composite section), it is necessary to define separate materials for every stage even if the material properties are the same for both parts.

Extra material constants may be defined for any type of material (AQUA:MEXT record). Please refer to AQUA manual for more details:

../../_images/materials-03.png

Cross-section definition

Important

This is a general description, which can be different from the project discussed in specific tutorial. Please make the necessary adjustments by yourself.

Inside the SSD task-tree the task “Cross Sections” is one of the default settings.

../../_images/cross-section_tree.png

With a right mouse click on this task you open the context menu. Select the command New Standard Section and decide, which type of cross section you want to define.

The following standard cross sections are available:

../../_images/cross-section-menu.png

Note

Simply use the right mouse click function to generate as many standard cross sections as necessary. Specific bridge cross sections will be generated later via SOFiPLUS - Cross Section Editor.

For user defined cross sections please use the cross section editor inside SOFiPLUS. You may select between a New Solid Section or a New Thin Walled Section.

../../_images/cross-section-graphical.png

Prestressing System

Important

This is a general description, which can be different from the project discussed in specific tutorial. Please make the necessary adjustments by yourself.

Please add a new SSD-task Prestressing Systems to your project. With a right mouse click on this task you open the context menu. Select the option New and generate a new prestressing system. Simply fill out all necessary information within the three tabs.

../../_images/prestressing-01.png ../../_images/prestressing-02.png ../../_images/prestressing-03.png

It is also possible to import prestressing systems from a different database. Simply use the right mouse click on the task and select the command Import.

Action Manager

A new task called “Action Manager” will be added to our bridge project. Define all necessary actions for the bridge design in this task before starting to model the bridge within SOFiPLUS.

../../_images/actions-01.png

We recommend the following list of actions.

Description

Action

PART

SUPP

Self weight

G_1

G

PERM always

Additional Dead load

G_2

G

PERM always

Temperature

T

Q

EXCL exclusive

Settlement

F

Q

COND conditional

Traffic load TS

GR_T

Q_1 Load Group 1

EXCL exclusive

Traffic loads UDL

GR_U

Q_1 Load Group 1

EXCL exclusive

Prestressing

P

P

PERM always

Note

Action for Creep and Shrinkage will be defined later on inside the construction stage manager CSM

System Generation within SOFiPLUS

Open SOFiPLUS from the SSD task “SOFiPLUS(-X) GUI Model creation”.

Note

It may be useful to collect and write down all necessary project data before starting with the system generation. E.g.:

  • bridge geometry information including axes information

  • cross section geometry

  • construction sequence including influence on cross sections and bridge structure

  • concept for element group numbering. All elements such as beams, quads, springs, couplings are organised in groups.

Inside the SOFiPLUS window all necessary commands are organised in a Sidebar on the left side. Tab “System” repeats the options from SSD to define materials, cross sections and prestressing systems. You also find the command to define new geometric axes.

../../_images/sofp-system.png

Define Bridge Axis

First we define a new bridge axis. Go to sidebar > tab “System” and use the right mouse click on the command “Geometric Axes”. From the possible commands we use the option “New Axis..”.

../../_images/sofp-axis-01.png

Now define a new name for your axis.

Warning

There are only 4 letters and/or numbers allowed for the axis name.

../../_images/sofp-axis-02.png

Confirm the name with “OK” and you will get into the first dialogue, where you define the horizontal alignment of the new bridge axis. Most important is to understand the concept of stations along the axis. Just imagine you start walking along the axis for 15.0 m and you started at station 10.0 m. Now you stop at station 25.0 m = 10.0 +15.0 m . For further description please see the SOFiPLUS manual.

../../_images/sofp-axis-03.png

Note

We recommend to define your axis longer than your real bridge length. Usually an extension of 10.0 m at the beginning and > 10.0 m at the end of the bridge is sufficient. This is necessary to add bridge elements later on, because you are not allowed to use negative station values.

After the horizontal alignment you define the vertical alignment. Usually you can use the information from the bridge layout drawing.

../../_images/sofp-axis-04.png

A very important option is to define variables along the bridge axis. These variables can be used for the cross sections generation later on. The idea is to define a master cross section with all necessary variables inside. During the meshing process the program will use cross section and variable information to generate all necessary interpolated cross sections for the final finite element mesh.

Warning

You are not allowed to use variable for material numbers inside the cross section. It is also not possible to use variables for the area of longitudinal reinforcement along the bridge axis.

../../_images/sofp-axis-05.png

A next important step is to define placements along the bridge axis. Placements represent special points along the bridge axis to define supports, construction points, beginning and end of a bridge structure. We will use these placements later on for an easy and fast system generation with structural lines and structural areas. They are also very important for the influence line evaluation later on. Support placements will be used together with the cross members editor later on to generate support elements and align them automatically with the placements and the axis.

../../_images/sofp-axis-06.png

The last setting during the axis generation is the option to define secondary axes. Secondary axes can be used for grid structures to define the positions of multiple beams parallel to the bridge axis, or also for shell bridges to define the boundary of the bridge including the position where the shell thickness changes.

You do have two options to generate a scondary axis. With a right mouse click on the option “Secondray Axes” you have two options. The first one generates a secondary axis with a fixed offset in y and/or z direction. With the second option you can create a secondary axis from any AutoCAD 3D curve available inside your drawing.

../../_images/sofp-axis-07.png ../../_images/sofp-axis-08.png

Note

At the moment the secondary axis are always parallel to the main bridge axis. It is only possible to define a constant offset in y and z direction.

Define Cross Sections

Besides the standard cross sections, we already defined inside the SSD, we will now define more complex bridge cross sections. This will be done within the Cross Section Editor inside SOFiPLUS. First go to the “System” tab and use the right mouse click on “Cross Sections” . We want to define a new solid cross section for reinforced concrete.

../../_images/sofp-cse-01.png

Note

You will find detailed descriptions and videos, how to use the cross section editor, in our bridge tutorials.

Define Bridge Geometry

Whether you will use beam or shell elements, defining the bridge geometry follows the same principles based on an existing bridge axis. Go to the tab “Structural Elements”and select a command “Line” or “Area”. Use the right mouse click to open the context menu and select the command “SEGment on geometric axis”. Now click on the axis in your drawing area. The next context menu opens. Select the command “Between all placements”. The program will automatically generate structural elements between all predefined placements.

../../_images/segment-on-axis.png ../../_images/between-all-placements.png

For more detailed information please see the different bridge tutorials.

Define Tendons

The tendon geometry and the tendons will be defined graphically inside SOFiPLUS. There are two general options to define tendons inside SOFiPLUS:

  • with “PT Editor” based on bridge axis

  • with “Tendon (Draw)” command based on existing AutoCAD spline or line objects.

Note

In case you do have multiple beams you should use secondary axes to define the beam elements and also to define the tendon geometry.

For new bridges the “PT Editor” is the most useful command, we recommend to use. Simply go to the sidebar tab “Prestressing” and select the command “PT Editor (Developed Geometry)”. Please be careful according to the elements you are using inside your system. In case of beam elements you must use the command below the title “Beam PT: Create and Modify”.

../../_images/tendon-01.png

In the next step you must select a geometric axis as a reference. Inside the upcoming dialogue all settings for the tendon geometry and the tendons are defined according to the selected bridge axis. The general principle is to define one tendon geometry and use this geometry to define multiple tendons if necessary with different start and end stations for every single tendon. The tendon geometry is a spatial spline defined by several Geometry Points. Inside the table of Geometry Points you may edit every setting. Alternatively you may select multiple points and change the settings of all selected points inside the Properties field.

../../_images/tendon-03.png

Clicking on the “Edit Tendons” button you get into the Tendon definition dialogue. The first tendon is already set inside the table. With the button “Draw Tendon” you may define new tendons with variable start and end stations. Important is to define a load case for the static determinant tendon forces and moments. Usually we recommend to have the necessary load cases defined before you start defining the tendons. Nevertheless it is also possible to generate a new load case right from this dialogue. In case you define a load case (LC0) the static determinate forces and moments are saved separately inside this load case. Usually this input is not necessary. The CSM procedure, described later, will automatically take care of the two parts of the prestressing forces and moments.

../../_images/tendon-04.png

After defining all tendons you see a list of all tendons in the sidebar. In case you want to define new tendons, which are parallel to your already defined tendons, you may use the command “Clone…”, or “Copy…” from the context menu. Simply use the right mouse click on any “Tendon geometry”. In case you want to clone a tendon geometry, the new ones have a fixed offset in y- and z-direction related to the connected bridge axis. In the other case, you make a copy with the ability to edit all properties.

../../_images/tendon-05.png

In case you want to edit the tendon properties simply double click on the tendons listed in the sidebar.

Note

Editing the cloned tendon geometry is not possible.

Now the tendon generation process is finished.

Define Load Cases

We recommend the following list of load cases. All these load cases are defined inside SOFiPLUS > Loadcase Manager tab “Loadcases”.

Basic Loads

LC Number

Description

Action

1

self-weight structure

NONE

2

additional dead load (e.g asphalt)

NONE

51-5X

settlement in every support axis, e.g. 10 mm

F

81-82

uniform temperature load

NONE

83-84

temperature difference

NONE

91-98

temperature combinations delta TN + wm*delta TM and wn*delta TN + delta TM

T

Note

  • The load cases 1 and 2, self weight and additional dead load, will be used later on inside the construction stage manager (CSM). Processing the construction stages, the load cases will be connected automatically to the corresponding action types. Connecting LC 1 and 2 to action “NONE” will secure, that they will not be used twice in a manually defined combination later on.

  • According to the code, a combination of temperature loads is necessary. This will be done in a separate user task .

Traffic Loads

LC Number

Description

Action

120x

load train e.g. LM1 with 300 kN axle load

NONE

2xx

envelope from “Traffic Loader”, TS Load Group 1

L_T

3xx

envelope from “Traffic Loader”, UDL Load Group 1

L_U

Define Loads

For defining loads, you may follow two general principles:

  • Element Loads

  • Free Loads

Element loads are directly related to a structural point, line or area. In case the geometric properties of these elements changes, the load changes as well. As we are defining our bridge system according to a bridge axis, we also want our loads to follow the axis, in case we change the axis parameters of our bridge. For that reason we recommend to use “Element Loads” for bridge design.

The “Free Loads” are based on the geometric input. Later on, during the meshing process, the loads will be connected to existing elements. In case no element can be found also no loads will be applied.

Note

If any load is not fully applied to the elements, there will be a warning:

../../_images/sofp-warning999.png

Mesh System

To start the meshing process click on the export button on the top left of the sidebar.

../../_images/sofp-export-00.png

The export dialogue contains two tabs: “Common” and “Text Output”. Usually the default settings are sufficient and you simply click “OK” to start the automatic mesh generation. The settings inside the tab “Text Output” control the amount of output. The standard rule in SOFiSTiK is, that the maximum amount of output is based on the settings before any calculation. Later on it is possible to reduce (or increase again) the existing output in the documentation (Report). But you cannot increase a non-existing output without a new calculation.

../../_images/sofp-export-01.png ../../_images/sofp-export-02.png

Now the input is finished and we can go back to the SSD window. Usually you may close the SOFiPLUS window.

Linear Analysis

Before we start analysing all existing load cases, we have to create combined temperature loads.

Combination of Temperature Loads

Temperature loads will be combined according to the requirement of the code later on in the SSD project, with a task “User Text”, because this is very easy to do numerically.

The input sequence is printed below:

+PROG SOFILOAD
HEAD Temperature Load Combinations
$ Load combinations
LC 91 TYPE T TITL 'T summer posdt TN+wm*dT' ; COPY 81           ; COPY 83 FACT 0.75
LC 92 TYPE T TITL 'T summer negdt TN+wm*dT' ; COPY 81           ; COPY 84 FACT 0.75
LC 93 TYPE T TITL 'T winter posdt TN+wm*dT' ; COPY 82           ; COPY 83 FACT 0.75
LC 94 TYPE T TITL 'T winter negdt TN+wm*dT' ; COPY 82           ; COPY 84 FACT 0.75
LC 95 TYPE T TITL 'T summer posdt wn*TN+dT' ; COPY 81 FACT 0.35 ; COPY 83
LC 96 TYPE T TITL 'T summer negdt wn*TN+dT' ; COPY 81 FACT 0.35 ; COPY 84
LC 97 TYPE T TITL 'T winter posdt wn*TN+dT' ; COPY 82 FACT 0.35 ; COPY 83
LC 98 TYPE T TITL 'T winter negdt wn*TN+dT' ; COPY 82 FACT 0.35 ; COPY 84
END

Task “Linear Analysis”

For the linear analysis we add the task “Linear Analysis” to our project file. When opening this task all available load cases within the database are selected for analysis. As we do have self weight, additional dead load and the single temperature loads in our database, but we don’t want to have them used in our project we change the selection manually.

../../_images/linear-analysis-01.png

In every SSD task there is a tab “Graphical Output”. These pictures are designed for a simple 2D slab project. Therefore we recommend to switch of all standard graphics. We will generate our own graphics in a separate task called “Interactive Graphic”.

../../_images/linear-analysis-02.png

Traffic Loader

Important

This section describes the general settings of the Traffic Loader Task. It contains explanations of the corresponding dialog options, grouped by tab. The CADINP input per dialog is shown as example. This is a supplement to the tutorials. It does not contain step-by-step instructions for applying traffic loads according to the concept of influence lines.

Overview

../../_images/76.png

Lanes

Inside the dialogue there are 5 tabs. The first tab - Lanes - you define the lanes, where the traffic passes over your bridge.

../../_images/77.png
+PROG SOFILOAD $ Traffic Loader
HEAD POSITIONAL VARIANTS OF LOAD TRAINS
PAGE UNII 0

LANE AXIS TYPE EN WL -9 WR 9 YLA -10 YRA 10
ECHO LANE FULL
...
END

Eurocode EN 1992-2 Table 4.1 Number of notional lanes

  • By selecting the standard cross-section “EN” the rules of table 4.1 are applied.

  • Depending on the dimensions, several lane orientations are generated: “centered”, “right”, “left” and “superstructure width”

  • The idea behind it: The resulting lane orientations are used to load the bridge unfavorably.

  • Ultimately, the user has to decide for himself, which lanes/notional lanes have to be loaded with which load trains.

  • If necessary, lanes/notional lanes can be created manually.

../../_images/79.png

Note

EN 1991-2 Chapter 4.2.4(2): (2) For each individual verification (e.g. for a verification of the ultimate limit state of resistance of a cross-section to bending), the number of lanes to be taken into account as loaded, their location on the carriageway and their numbering should be so chosen that the effects from the load models are the most adverse.

Definition of the terms ‘lane’, ‘notional lane’ and ‘residual area’

  • A ” lane ” contains a left and right edge and a line yc, which does not have to be located centrally between the edges. The vehicle moves along the line yc. Loads always act only within the loaded lane, loads outside the lane are “clipped”, i.e. simply ignored.

  • A “notional lane” results only through the load train, which is applied in a lane: the load train LM1 has a defined width of 3.00 m; if this is applied in one lane, the “notional lane” results to exactly this width, i.e. 3.00 m; this notional lane is centered on the line yc within the lane.

  • A “residual area” is always within the loaded lane next to the vehicle: If a lane has a width of 4.00 m and an LM1 is placed on this lane, a “residual area” of 0.50 m width results to the right and left of the LM1 (of the notional lane) when yc is positioned centrally.

Alignment

The following lane orientations are automatically generated when selecting stand cross-section “EN”.

Note

If there is exactly space between the curbstones for 1,2,3,4,5 or 6 lanes (i.e. 3.00 m, 6.00 m, … 18.00 m), a lane orientation is generated “centered”: Lanes 1 to 6 are arranged side by side from right to left, all of them have a width of 3.00 m. In the graphic, the “notional lanes” that would result with a 3.00 m wide vehicle within the lane are highlighted in light blue.

../../_images/78.png

The following lane orientations are automatically generated when selecting stand cross-section “EN”.

  • From more than approx. 20.00 m between the curbstones, a lane alignment is also generated “centered”. Again, all lanes from 1 to x are numbered from right to left, but these are arranged in the middle between the curbstones. All lanes in the middle have a width of 3.00 m, only the two edge lanes reach to the curbstones and have a larger width. In these wider lanes, the “notional lane” is again indicated in light blue, which would result in a 3.00 m wide vehicle.

../../_images/85.png
  • Edge lanes 1 and 7 are wider than 3.00 m

  • The line yc is, for example, for lane 1 1.50 m next to the left edge of the lane. Thus, a vehicle would drive eccentrically in this lane.

  • The lane widths are verifiable in the lane table

The following lane orientations are automatically generated when selecting standard cross-section “EN“:

  • If there is a width between the curbstones unequal to an integer multiple of 3.00 (and up to a maximum of about 20.00 m), the lane alignments are generated “centered”, “right” and “left”.

  • At the alignment “centered” the lane 1 is in the middle, then alternately follow right, left, right, left lanes 2, 3, 4 and 5 (up to a maximum of 5 lanes). The middle lanes have a width of 3.00 m each, only the edge lanes reach with an edge to the curbstone and are therefore wider.

../../_images/87.png
  • Edge lanes 4 and 5 are wider than 3.00m

  • The line yc is, for example, for lane 4 1.50m next to the lane. Thus, a vehicle would drive eccentrically in this lane.

  • The lane widths are verifiable in the lane table

The following lane orientations are automatically generated when selecting standard cross-section “EN“:

  • With the “right” alignment, lane 10 is right-aligned on the curbstone, lanes 11 to a maximum of 15 follow on the left.

../../_images/89.png

The following lane orientations are automatically generated when selecting standard cross-section “EN“:

  • With the “left” alignment, lane 20 is left-aligned on the curbstone, followed by tracks 21 to a maximum of 25 on the right.

../../_images/91.png

The following lane alignments are generated automatically:

  • In addition, a lane “0” is defined in all cases. This is the “overall width”, i.e. the width between the curbstones plus the width of the cycle path or footpath and is referred to, as the “superstructure width”. In order to load the cycle/footpath, the remaining areas of lane “0” are addressed.

../../_images/93.png
  • Lane 0 => Superstructure.

  • The residual areas of lane 0 are the cyle/footpaths.

Residual Area

../../_images/94.png

Distribution of lanes in the bridge cross-section - residual area

Important

Residual areas are always part of a lane! This means that the edge lanes in the image have a widt of 3.00m + width of the residual area, see also below!

Results

../../_images/95.1.png

In the Report of PROG SOFiLOAD, from task Traffic Loader, you will find informations about lane geometry (ECHO LANE FULL).

Important

These should always be checked!

Load Trains

../../_images/96.png
+PROG SOFILOAD $ Traffic Loader
HEAD POSITIONAL VARIANTS OF LOAD TRAINS
PAGE UNII 0

LANE AXIS TYPE EN WL -2.6 WR 2.6 YLA -3.15 YRA 3.15

ECHO LANE FULL

$ Input Load Trains
LC NO 1200 TYPE none TITL 'EN 1991-2 Load model LM1'
TRAI LM1 P1 300 P2 300 P4 9 P5 2.5 P8 1 PFAC 1 WIDT 3
$ Input Load Trains
END

Calculation

../../_images/97.1.png

Important

in the dialog, no evaluation of the RSETs can be selected yet!

This has to be done manually at the moment. Recommended workflow:

Make all necessary and possible settings in the dialog, disable the option “Run Immediately” at the bottom left and exit the dialog with “OK”. Then copy the task, convert it to a text task and manually add required lines regarding the RSETs (see the following pages). Then open the original task with the teddy and deactivate the modules -> this ensures that when the complete task tree is recalculated, only the manually adapted task is calculated.

+PROG ELLA urs:32.1 $ Traffic Loader
HEAD AUTOMATIC EVALUATION OF LOAD TRAINS
PAGE UNII 0
SIZE URS 0 HDIV 3 $ 0.30
ECHO OPT LPOS VAL FULL $ Load position
SHOW SNO AXIS TYPE BEAM NO 200010 ETYP EXTR

$Input Calculation Tab
LSEL AXIS INT 0 DZ 0.1 $ RSEL GRP 0
CALC N LMAX 2 LMIN 1
CALC VY LMAX 4 LMIN 3
CALC VZ LMAX 6 LMIN 5
CALC MT LMAX 8 LMIN 7
CALC MY LMAX 10 LMIN 9
CALC MZ LMAX 12 LMIN 11
CALC P LMAX 14 LMIN 13
CALC UX LMAX 16 LMIN 15
CALC UY LMAX 18 LMIN 17
CALC UZ LMAX 20 LMIN 19
APPL FULL
$Input Calculation Tab
...

Distribution of loads - Beam systems

../../_images/98.png

Distribution of loads - Area elements

../../_images/99.png

Necessary addition for RSETs

  • In PROG ELLA, a superposition of the RSET values must now also be requested

  • In the CALC command, the input RSET:…

  • The input CALC RSET:PX requests the determination of the maximum RSET size ‘PX’ (again analogue to the input CALC MY, which requests the determination of the maximum beam force MY)

  • Just as CALC MY treats all beams, that have the internal forces MY, CALC RSET:PX treats all RSETs that contain this RSET value

  • For the RSETs a reasonable numbering LMAX and LMIN must be selected

 +PROG ELLA urs:32.1 $ Traffic Loads
HEAD AUTOMATIC EVALUATION OF LOAD TRAINS
PAGE UNII 0

 SIZE URS 0 HDIV 3 $ 0.30

 SHOW SNO AXIS TYPE BEAM NO 200010 ETYP EXTR

 LSEL AXIS INT 0 DZ 0.1 $ RSEL GRP 0
 CALC N LMAX 2 LMIN 1
 CALC VY LMAX 4 LMIN 3
 CALC VZ LMAX 6 LMIN 5
 CALC MT LMAX 8 LMIN 7
 CALC MY LMAX 10 LMIN 9
 CALC MZ LMAX 12 LMIN 11
 CALC P LMAX 14 LMIN 13
 CALC UX LMAX 16 LMIN 15
 CALC UY LMAX 18 LMIN 17
 CALC UZ LMAX 20 LMIN 19

 $ addition for RSETs
 let#start 21
 CALC RSET:PX LMAX #start+1 LMIN #start
 CALC RSET:PY LMAX #start+3 LMIN #start+2
 CALC RSET:PZ LMAX #start+5 LMIN #start+4
 CALC RSET:VX LMAX #start+7 LMIN #start+6
 CALC RSET:VY LMAX #start+9 LMIN #start+8
 CALC RSET:VZ LMAX #start+11 LMIN #start+10
 CALC RSET:PHIX LMAX #start+13 LMIN #start+12
 CALC RSET:PHIY LMAX #start+15 LMIN #start+14
 CALC RSET:PHIZ LMAX #start+17 LMIN #start+16
 $ addition for RSETs
 APPL FULL

Load Groups

../../_images/102.2.png
+PROG ELLA urs:32.1 $ Traffic Loader
HEAD AUTOMATIC EVALUATION OF LOAD TRAINS
...
SAVE LCB 100 TYPE GR_T TITL 'TS'
CASE 1 GRP GR0
POSL AXIS.1 TRAI 1200 FACT 1 YEX 0 P 2.5 SYNC OFF PLON VAR PTRA VAR FUGA CODE IMPA ON EXCE FIX EXTR ALL OPT FREE
CASE 2 GRP GR0
POSL AXIS.1 TRAI 1200 FACT 1 YEX 0 P 2.5 SYNC OFF PLON VAR PTRA VAR FUGA CODE IMPA ON EXCE FIX EXTR ALL OPT FREE
CASE 3 GRP GR0
POSL AXIS.1 TRAI 1200 FACT 1 YEX 0 P 2.5 SYNC OFF PLON VAR PTRA VAR FUGA CODE IMPA ON EXCE FIX EXTR ALL OPT FREE

SAVE LCB 200 TYPE GR_U TITL 'UDL'
CASE 1 GRP GRU
POSL AXIS.1 TRAI 1200 FACT 1 YEX 0 P 2.5 SYNC OFF PLON VAR PTRA VAR FUGA CODE IMPA ON EXCE FIX EXTR ALL OPT FREE
CASE 2 GRP GRU
POSL AXIS.1 TRAI 1200 FACT 1 YEX 0 P 2.5 SYNC OFF PLON VAR PTRA VAR FUGA CODE IMPA ON EXCE FIX EXTR ALL OPT FREE
CASE 3 GRP GRU
POSL AXIS.1 TRAI 1200 FACT 1 YEX 0 P 2.5 SYNC OFF PLON VAR PTRA VAR FUGA CODE IMPA ON EXCE FIX EXTR ALL OPT FREE
CASE 4 GRP GR3
POSL AXIS.0 P 2.5

COMB A0 1 1.0 4 1.0
     A0 2 1.0 4 1.0
     A0 3 1.0 4 1.0

Note

Categories to map load groups: By defining the parameter ACT… PART Q_1, Q_2, Q_3 … these effects are treated in the same way as the load groups in Table 4.4a: only load cases of either group Q_1 or Q_2 or Q_3 … A call in the PROG MAXIMA with ACT GR _ … automatically considers these categories of action GR with correct psi values. MAXiMA also knows, that the categories GR_T and GR_U can act simultaneously, since both were defined as PART Q_1

+PROG SOFiLOAD
HEAD 'ACTIONS'

ACT 'GR_T' GAMU 1.35 0.00 PSI0 0.75 0.00 PART Q_1 SUP EXCL TITL "gr1a TS"
ACT 'GR_U' GAMU 1.35 0.00 PSI0 0.40 0.40 PART Q_1 SUP EXCL TITL "gr1a UDL"
ACT 'GR_2' GAMU 1.35 0.00 PSI0 0.00 0.00 PART Q_2 SUP EXEX TITL "gr2 Horizontal Forces"
ACT 'GR_3' GAMU 1.35 0.00 PSI0 0.00 0.00 PART Q_3 SUP EXEX TITL "gr3 Footways"
ACT 'GR_4' GAMU 1.35 0.00 PSI0 0.75 0.75 PART Q_4 SUP EXEX TITL "gr4 crowd load"
ACT 'GR_5' GAMU 1.35 0.00 PSI0 0.00 0.00 PART Q_5 SUP EXEX TITL "gr5 LM3 freq LM1"

END
../../_images/104.1.png

Table EN 1991-2- Table 4.4a - Groups of traffic loads

Text Output

../../_images/105.png
+PROG ELLA urs:32.1 $ Traffic Loader
HEAD AUTOMATIC EVALUATION OF LOAD TRAINS
PAGE UNII 0

SIZE URS 0 HDIV 3 $ 0.30

ECHO OPT LOAD VAL YES $ Loadtrains
ECHO OPT EVAL VAL NO $ Evaluation
ECHO OPT LPOS VAL FULL $ Load positions
ECHO OPT RES VAL NO $ Results

SHOW SNO AXIS TYPE BEAM NO 200010 ETYP EXTR
...

Results

For Results please open the Report Browser:

../../_images/108.png ../../_images/107.png

Construction Stages

With the construction stage manager we are able to analyse the whole building process. This process will effect the forces and moments inside our structure and cannot be neglected. When having prestressed or composite structures the CSM is mandatory.

Before adding the SSD task “Construction Stage Manager (CSM)” from our task library, you should set up a time line with all necessary incidents. Construction stages are defined inside cross sections and also inside the tendon geometry and layout already made in SOFiPLUS. All elements of your structural system are organised in groups. This is important as you may activate and also deactivate single groups of elements at any time during the construction process.

Note

Usually there are different incidents between two major stages like prestressing, grouting, temporary loads, creep and shrinkage. For that reason it is useful to increase the stage number by 10. This enables you also to add new stages in between, without renumbering everything.

Recommended Stage Numbers:

  • 10th: a new group of elements is active

  • 11th: prestressing, static determinate part

  • 12th: prestressing, static indeterminate part

  • 13th: grouting (optional)

  • 14th: new loads, e.g. formwork

  • 15th: up to 4 creep and shrinkage steps (15,16,17,18)

  • 19th: for precamber analysis or activation of self weight from cross section stage

The first construction stage should start with stage number 10.

If all the predefinion work is finished, you may insert the CSM task and open it. Inside this dialogue the first three tabs are the most important ones.

The first table contains a list of all construction stages. This describes the timeline of all incidents of our structure. Only the creep and shrinkage stages have a time duration.

../../_images/csm-014.png

The second table defines the properties and activation stages of all element groups.

../../_images/csm-023.png

The third table defines the properties and activation stages of load cases during the construction process.

../../_images/csm-033.png

For checking purposes it is possilbe to select specific elements direct from the ANIMATOR. You do have this option inside the tab “Beam selection for check print”.

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The remaining two tabs are dealing with control parameters and the amount of output. For the first application the default settings are good. If you close the input with the “OK” button the option “Process immediately” is active and the whole process starts.

Important to know is the fact, that all the results are saved again in a serie of load cases. The numbering follows a very clear concept.

../../_images/csm-04.png

Overview of load cases used by CSM:

CSM Construction stages:

LC Number

Description

3970- 3997

Comparison load cases - cast in one (CTRL cast)

4000- 4999

Total CS displacements and forces without pre-stress losses from C+S

5000- 5999

Difference displacements and forces -> CSM DESI with safety factors

6000- 6999

AQB inner stresses from creep and shrinkage including pre-stress losses -> CSM DESI

7000- 7999

Sum stress results (real stresses) of the AQB−LCST−evaluation incl. pre-stress losses from C+S

15000- 15999

Primary part effect of prestress separated in construction stages

16000- 16999

Secondary effect of prestress in construction stages using more than 1000 stages:

40000-49999

Total CS displacements and forces

50000-59999

Difference displacements and forces

60000-69999

AQB inner stresses from creep and shrinkage

70000-79999

AQB-LCST result stresses (real stresses)

For CSM new segments with CTRL CANT 3:

LC Number

Description

180000-189999

help load cases for analysis of restraint

For CSM precamber analysis (CAMB)

LC Number

Description

140000-149999

Total CS displacements without CAMB modification

For CSM Equation System usage

LC Number

Description

1999

CSM_Combination loadcase (CTRL LCEQ)

For CSM DESI Design usage

LC Number

Description

1101-1199

SLS rare (characteristic) superposition and design

1201-1299

SLS nonfrequent superposition and design

1301-1399

SLS frequent superposition and design

1401-1499

SLS permanent superposition and design

1701-1799

SLS construction design rare (characteristic)

1801-1899

SLS construction design permanent

1901-1998

1.0 superposition

2101-2199

ULS design

2201-2299

ULS construction design

2501-2599

Accidential

2601-2699

Earthquake

2801-2899

Fatigue LM3 with pk-inf and pk-sup prestress

2901-2999

Fatigue simplified LM1 with pk-inf and pk-sup prestress

9001-9499

Superposition with pk-inf and pk-sup prestress

Note

In case of more than 1000 construction stages, the number of the result load cases is increased by a factor of 10 to 40000-49999 and so on.

Combinations and Superpositioning

For the design process a combination in ULS and SLS state of all loads is necessary. For prestressed, post tensioned or composite beam bridges it is necessary to have the combinations from all loads, acting on the final bridge construction separate. The final combinations are done in the beam design program AQB. The module CSM is able to generate all necessary combinations.

To apply the automatic generation of all necessary combinations, add a task “CSM Bridge Design - Superpositioning” inside your project. Besides the default selection of actions like GR_T, GR_U, you need to select the actions you want to have inside your further superpostioning and design.

../../_images/csm-maxi-01.png

Note

For the pure Eurocode it is sufficient to have only one action F..settlement. According to the German Code it is necessary to have two different actions for settlements which will be used for different design checks:

  • possible settlement SF will be used for ULS design check

  • probable settlement ZF will be used for SLS design check

Design Checks

According to the code selected at the beginning of the project, several design checks are necessary. Again, the module CSM is able to generate all necessary design checks automatically. Simply add a new Task “CSM Bridge Design - Beams” to your project. You may select the necessary design checks inside this task. In case you want to separate the different design checks, you may insert this task multiple times with different settings.

../../_images/csm-desi-01.png

For a detailed output of specific beam sections, you may select these sections graphically from the ANIMATOR. The selection is saved inside the task on tab “Beam selection for check print”.

../../_images/csm-desi-02.png

Note

This task is only available after the task “CSM Bridge Design - Superpositioning” was added to your project!

With every CSM run a new file $(name)_xxx.dat is generated automatically. The variable $(name) represents the project name and the XXX represents a number. If you right click on the task “CSM Bridge Design - Beams” > “Test Editor” you may open the text file generated by this task. There you will see the number generated by the program, which will be used for the new generated file.

../../_images/csm-desi-03.png

It is always helpful to have a view inside this generated TEDDY input file. You may open this file from the menu bar, TEDDY icon > “Open Text File”. See the following picture.

../../_images/open-text-file.png

Generate Report

In SSD, every single task produces a report file project.plb. For a graphical visualisation of all results we recommend to add several tasks “Interactive Graphic”. You may move these tasks at any place inside your task-tree. Usually it is helpful to have system plots, plots with the resulting forces and moments and finally some plots with the design results.

Note

In every task “Interactive Graphics” you may define as many pictures as you want. Lots of pictures may slow down the performance. Therefore we recommend to use multiple tasks for graphical results.

There is an option to generate a complete documentation file. Go to SSD ribbon tab “Home” > “Report”.

../../_images/docu-01.png

Inside the complete document you may insert a table of contents. This can be done inside the Report Browser ribbon tab “Home”. Simply mark the option “Table of Contents”, see picture below.

../../_images/docu-02.png

To have a secure output file we recommend to print the final document to a pdf file. This can be done easily with the print function from the Report Browser. Open the Report Browser and go to menu “File” > “Export to PDF”

../../_images/generate-pdf.png

Save Project Files

After the project is finished, all calculations are done and a final report was generated, you should save your project on a company server. For that reason we recommend to pack your project files together in one project.zip file. Simply go to SSD ribbon tab “Home” > “Tools” or use the button Archive.

../../_images/archive.png

Note

To reproduce a project, only the files project.sofistik and project.dwg are necessary.