Analysis Guide 170 Enu

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Tekla Structures

Analysis Guide

Product version 17.0

December 2010

2010 Tekla Corporation


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2010 Tekla Corporation and its licensors. All rights reserved.

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TEKLA STRUCTURES 17 3

Conventions used in this guide

Typographicalconventions

The following typographical conventions are used in this guide:

Noteboxes The following types of noteboxes are used in this guide:

Font Usage

Bold Any text that you see in the user interface appears in bold. This fontis used, for example, for window and dialog box titles, box and

button names, and list items.

I tal ic bo ld New terms are in i ta l ic bo ldwhen they appear in the current contextfor the first time.

Monospace Extracts of program code, HTML, or other material that you wouldnormally edit in a text editor, appear in monospaced font.

This font is also used for file names and folder paths, and for anytext that you should type yourself.

A tip might introduce a shortcut, or suggest alternative ways of doingthings.

A note draws attention to details that you might easily overlook. It canalso point you to other information in this guide that you might finduseful.

You should always read very important notes and warnings, like thisone. They will help you avoid making serious mistakes, or wasting yourtime.

This symbol indicates advanced or highly technical information thatis usually of interest only to advanced or technically-oriented readers.


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Contents

Conventions used in this guide ........................................................................................................................... 3

1 Getting Started wi th Analysis ................................................................... 7

1.1 Basics..................................................................................................................................................... 7

Carrying out structural analysis.......................................................................................................... 9

Members, bars and area objects...................................................................................................... 10

Nodes and rigid links........................................................................................................................ 10

1.2 Determining member properties........................................................................................................... 11

Member analysis class..................................................................................................................... 12

Support conditions........................................................................................................................... 14

Defining support conditions.............................................................................................................. 15

Support condition symbols............................................................................................................... 16

Analyzing composite beams............................................................................................................ 18

Viewing analysis results ............................................................................................................ 18

Manual method - limitations ...................................................................................................... 19

Design information........................................................................................................................... 19

Member position............................................................................................................................... 20Analysis member offsets.................................................................................................................. 21

Analysis properties of components.................................................................................................. 22

Analysis properties of slab components........................................................................................... 23

Properties of intermediate members................................................................................................ 24

Defining buckling lengths (columns) ................................................................................................ 24

Effective buckling length ............................................................................................................ 24

Kmode options .......................................................................................................................... 25

1.3 Analysis information and settings......................................................................................................... 26

A closer look at the analysis model.................................................................................................. 26Objects ...................................................................................................................................... 27

Nodes connecting members and elements ............................................................................... 27

Loads in analysis.............................................................................................................................. 28

Load modeling code......................................................................................................................... 29

Analysis method............................................................................................................................... 30

1.4 Additional information resources .......................................................................................................... 30

2 Loads ........................................................................................................ 31

2.1 Basics................................................................................................................................................... 31


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Automatic loads and load groups..................................................................................................... 32

2.2 Grouping loads..................................................................................................................................... 32

Load group properties...................................................................................................................... 33

Load group compatibility.................................................................................................................. 33

Working with load groups................................................................................................................. 34Checking loads and load groups ............................................................................................... 34

Changing the load group ........................................................................................................... 35

Importing and exporting load groups ......................................................................................... 35

2.3 Load types and properties.................................................................................................................... 35

Load types........................................................................................................................................ 36

Load forms....................................................................................................................................... 37

Load magnitude............................................................................................................................... 38

Temperature loads and strain.......................................................................................................... 39

2.4 Distributing loads.................................................................................................................................. 39Attaching loads to parts or locations................................................................................................ 39

Applying loads to parts..................................................................................................................... 40

Loaded length or area...................................................................................................................... 41

Modifying load distribution................................................................................................................ 41

2.5 Working with loads................................................................................................................................ 42

Changing loaded length or area....................................................................................................... 43

Scaling loads in model views........................................................................................................... 43

Defining varying wind loads............................................................................................................. 44

2.6 Load reference...................................................................................................................................... 45

Load Groups... ................................................................................................................................ 45

Create Point Load............................................................................................................................ 47

Create Line Load.............................................................................................................................. 48

Create Area Load............................................................................................................................. 49

Create Uniform Load........................................................................................................................ 50

Create Temperature Load................................................................................................................ 51

Create Wind Load............................................................................................................................ 52

3 Analysis and Design ............................................................................... 55

3.1 Analysis part properties........................................................................................................................ 55

3.2 Analysis model properties..................................................................................................................... 59

Objects in an analysis model........................................................................................................... 60

Analysis model filter .................................................................................................................. 61

Member axis..................................................................................................................................... 61

Member end connectivity................................................................................................................. 62

Model merging with analysis applications........................................................................................ 62

Analysis method............................................................................................................................... 62

Seismic analysis............................................................................................................................... 63


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6 TEKLA STRUCTURES 17

Modal analysis.................................................................................................................................. 64

Design codes and methods.............................................................................................................. 65

Design properties ....................................................................................................................... 65

Contents of STAAD.Pro results files and reports............................................................................. 65

3.3 Load combination.................................................................................................................................. 66

Load combination properties............................................................................................................ 66

Load combination factors................................................................................................................. 66

Load combination types................................................................................................................... 67

Creating load combinations.............................................................................................................. 68

Automatic load combination............................................................................................................. 69

Automatically including loads in combinations................................................................................. 70

Manual load combination................................................................................................................. 70

3.4 Working with analysis and design models............................................................................................ 71

Checking objects contained in an analysis model............................................................................ 71Adding or removing analysis objects................................................................................................ 72

Viewing analysis results................................................................................................................... 72

Exporting an analysis model ............................................................................................................ 72

Copying an analysis model .............................................................................................................. 73

Copying an analysis part.................................................................................................................. 73

3.5 Analysis and design reference.............................................................................................................. 73

Analysis > Analysis & Design Models... ........................................................................................... 74

Create Node..................................................................................................................................... 75

Create Rigid Link.............................................................................................................................. 76Merge Selected Nodes..................................................................................................................... 76

New... ............................................................................................................................................... 77

Creating analysis model rules .................................................................................................... 80

Add selected objects........................................................................................................................ 81

Remove selected objects................................................................................................................. 81

Load combinations... ........................................................................................................................ 81

Get results........................................................................................................................................ 82

Reset Editing Of Selected Parts....................................................................................................... 83


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Getting Started with Analysis

1 Getting Started withAnalysis

Introduction This chapter explains how to prepare a Tekla Structures model for structural analysis anddesign. It includes a general description of the principles of analysis and design and discussesthe theoretical basis of the analysis method used in Tekla Structures. This chapter also explainswhat is included in the analysis model, and how it is included. You will also learn how to definesupport conditions for parts.

Audience This chapter is for engineers and designers who run structural analysis on concrete and steelstructures.

Assumedbackground

We assume that you have created parts.

Contents This chapter is divided into the following sections: Basics (p. 7)

Determining member properties (p. 11)

Analysis information and settings (p. 26)

1.1 Basics

In this section This section presents the basic vocabulary and concepts we use to describe structural analysisin Tekla Structures. The illustrations below show the analysis concepts and procedures.


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Physical model A phys ica l modelincludes the parts you have created in the model, and information related tothem. Each part in the physical model exists in the completed structure.

Load model The l oad modelcontains information about loads and load groups. It also contains informationabout the building code Tekla Structures uses in load combination. To create a load model, see

Loads (p. 31).

Analysis model An analysis modelis used when structural analysis is run.Tekla Structures generates therequired analysis members automatically for the physical model parts when you have ananalysis model selected in the Analysis & Design models dialog box. The following analysisobjects are generated:

Nodes and analysis members and elements of the physical parts

Support conditions for nodes

Connectivity between the members and nodes

Loads to members and elements

The analysis model also includes load combinations.

Analysisapplication

Tekla Structures links with a number of analysis applications and also supports export withthem in several formats. The analysis application you use to run structural analysis uses datafrom the analysis model to generate analysis results.

For more information on the analysis applications that you can use with Tekla Structures, visitTekla Extranet at https://extranet.tekla.com. You can also access Tekla Extranet from TeklaStructures at Help > Online Support > Tekla Extranet.

Topics Carrying out structural analysis (p. 9)

Members, bars and area objects (p. 10)

Nodes and rigid links (p. 10)

Carrying out structural analysis

To carry out structural analysis in Tekla Structures:

1. Create the main load-bearing parts to form the physical model. See About parts. There isno need to detail or create connections at this stage.

Parts

Loads

Node

Analysis bar and member

Analysis model

Physical and load models

Tekla Structures analyzes parts using properties in the profile andmaterial catalogs, including user-defined properties. If there are no

profile or analysis properties in the catalog, Tekla Structures calculatesthem using the profile dimensions in the model.


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2. Create the load model. See Loads (p. 31).

3. Create a new analysis model and define its properties. See Analysis model properties (p.59) and New... (p. 77). The analysis parts are created automatically for the analysis model.

4. Set the support conditions for parts and connections, as well as other analysis propertiesfor individual members. See Determining member properties (p. 11).

5. Create load combinations. See Load combinations... (p. 81).

6. Check the analysis model in a Tekla Structures model view. See Checking objectscontained in an analysis model (p. 71).

7. Check the analysis parts and modify their properties if needed.

Now you are ready to run the analysis by exporting the analysis model. See Exporting ananalysis model (p. 72).

See also The following sections discuss the theoretical basis of the analysis method used in TeklaStructures. They also explain what is included in the analysis model, and how it is included.

Members, bars and area objects (p. 10)

A closer look at the analysis model (p. 26)

Loads in analysis (p. 28)

Load modeling code (p. 29)

Analysis method (p. 30)

Members, bars and area objects

Every physical part that you select to include in the analysis model is represented by ananalysis part, containing various analysis properties.

Frame objects(beams, columns, bracings) consist of one or more bars, and each bar objectconsists of one or more members. Specifically, a bar consists of one or more members which liealong the same line. In the most typical case, an analysis part consists of one bar, and one ormore members ifspl i t posi t ionsneed to be created on the bar. Split positions are created tocreate proper connectivity with intersections with other parts. An analysis part contains morethan one bar if it is a polybeam, or if it is tapered in a way that members do not lie on the sameline.

Some analysis engines work on members whereas others work on bars. This affects also thedrawing of the analysis model. Either member or bar numbers are drawn in the view.

Slabs and walls are modeled as area objec ts. When transferred to the analysis engine, meshing

creates the individual elements of the area object.

See also Determining member properties (p. 11)

Nodes and rigid links

Nodes Nodesconnect analysis members and elements. Tekla Structures creates nodes at:

The ends of members

The intersection points of member axes

The corners of elements

The following properties affect the exact location of nodes:

To create accurate analysis models, make sure that connected parts havecommon handles, for example, at grid line intersections.


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Part profiles, i.e. neutral axis and orientation

Part reference lines (see Part handles)

Location of member axes (see Member position (p. 20) and Member axis (p. 61))

Location and shape of elements

To force members to meet in the analysis model, Tekla Structures may need to merge nodes,

shift or extend member axes, create rigid links between nodes, ignore minor members, etc.

You can create additional nodes when needed. Sometimes, intermediate nodes are needed alonga member, for example, in frequency analysis.

For more information on where and how Tekla Structures creates nodes, members, andelements, see A closer look at the analysis model (p. 26).

Rigid links Rigid links are links between nodes that do not permit relative motion between them.

Rigid links have the following properties in the analysis model:

Profile = PL300.0*300.0

Material = RigidlinkMaterial

Density = 0.0

Modulus of elasticity = 100*109 N/m2

Poissons ratio = 0.30

Thermal dilatation coefficient = 0.0 1/K

See also Create Node (p. 75)

Create Rigid Link(p. 76)

1.2 Determining member properties

You can define analysis properties for individual parts, or for an entire analysis model. Thissection describes the properties of the individual analysis members. To define these, use theAnalysis, Start releases, End releases, Composite, Spanning, Loading, Design, Position,Bar Attributes and Area Attributes tabs in the analysis part properties dialog boxes, or theAnalysis tab in the connection and detail dialog boxes.

To display the analysis part properties dialog box, select the part and clickAnalysis > AnalysisPart Properties.

The methods used to create a physical model affect the analysis model.Because of this, you may need to try different modeling methods andanalysis model properties in order to create an accurate analysis modelof a complex physical model.

The analysis engine may model rigid links by dedicated rigid linkobjects.


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For more information on using common properties for the parts in an analysis model, seeAnalysis model properties (p. 59).

Topics Member analysis class (p. 12)

Member position (p. 20)Analysis member offsets (p. 21)

Analysis properties of components (p. 22)

Analysis properties of slab components (p. 23)

Analyzing composite beams (p. 18)

Support conditions (p. 14)

Defining support conditions (p. 15)

Design information (p. 19)

Properties of intermediate members (p. 24)

Defining buckling lengths (columns) (p. 24)

Member analysis class

Use the Analysis tab in the analysis part properties dialog boxes to define how Tekla Structureshandles individual members in the analysis. The following table lists the options in the Classlist.

Tekla Structures shows the member analysis class of parts using different colors in the analysismodel. The Color column lists these colors.


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Option Description Color

Beam Line object of two nodes.

Member can take any load, includingtemperature.

Dark red

Column Line object of two nodes.


Dark red

Secondary Line object of two nodes.


Members that are classified asSecondaryKeep axis position alwaysis off by default and secondary partssnap to nearest nodes instead of partend nodes.

Dark red

Wall Polygon object of three or more nodes.

For rectangular concrete panels andconcrete slabs using design codes ACIand BS 8110 only.

Tekla Structures analyzes the concretepanel or slab as a shear wall that doesnot take any direct loads.

Aqua

Slab Polygon object of three or more nodes.


Aqua

The options above combined with one of the following:

Truss Member can only take axial forces, notbending or torsion moments, or shearforces. Usually used for brace members.

Green

Truss - Tension

only

Member can only take tensile axialforces, not moments or shear forces. Ifthis member goes into compression, it isignored in the analysis.

Pink

Truss -

Compression only

Member can only take compressiveaxial forces, not moments or shearforces. If this member goes into tension,it is ignored in the analysis.

Yellow

Ignore Member ignored in the analysis.Self weight load is taken into account, ifyou have set the Generate self weightload toYes on the Loading tab.

Member isnot shown inthe model.

Shell Member can take any load, excepttemperature. Use to analyze slabs,

panels, and plates.

Aqua


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For more information on members with the Truss, Tension only, orCompression onlysetting, see A closer look at the analysis model (p. 26).

To indicate the member analysis class of parts in an object group using colors:

1. Click View > Representation > Object Representation....

2. Select the object group.

3. In the Colorcolumn, select Color by analysis type.

4. Click Modify.

For more information on object representation and object groups, see Object representationsettings and Object groups.


Support conditions

In structural analysis, the stresses and deflections of a part depend on how it is supported by, orconnected to, other parts. You normally use restraints or springs to model connections. Thesedetermine how analysis members move, deflect, warp, deform, etc., in relation to each other, orto nodes.

Member ends and nodes have degrees of freedom (DOF) in three directions. The displacement

of a member end can be free or fixed, and the rotation can be pinned or fixed. If the degree ofconnectivity is between free, or pinned, and fixed, use springs with different elastic constants tomodel them.

Tekla Structures uses part, connection, or detail properties to determine how to connectmembers in the analysis model. To define the member end conditions, use the Start releasesand End releases tabs in the analysis part properties dialog boxes. The connection and detaildialog boxes have Analysis tabs.

The analysis properties of a member determine the degrees of freedom for each end of a mainpart or member. The first end of a part has a yellow handle, the second end has a magentahandle. See also Part handles.

See also Defining support conditions (p. 15)


Rigid diaphragm Only applies to contour plates andconcrete slabs parallel to the global xy

plane.

Nodes that belong to a part matching

the filter will be connected with rigidlinks which together affectdisplacement. For example, you can usecolumn_filterto connect only columnnodes to rigid diaphragms.

Lilac

Plate Same as Shell but plate, membrane, ormat foundation elements are used in theanalysis application.

Aqua

Membrane Aqua

Mat foundation Aqua

The analysis application that you use may not support all options.

Option Description Color


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Defining support conditions

Parts Use the Start releases and End releases tabs in the analysis part properties dialog boxes todefine support conditions. The Start releases tab relates to the first part end (yellow handle),the End releases tab to the second part end (magenta handle).

Plates To define the support conditions of contour plates, concrete slabs, and concrete panels, use theSupported list box on the Area attributes tab in the analysis part properties dialog box.

Connections anddetails

Use the Analysis tab in the connection or detail dialog boxes to define the support conditionsfor the members and node in a connection. Use the Member selection list box to associate thesupport conditions with each connection part (Primary, 1. secondary, 2. secondary, etc.).

Supportconditions

Tekla Structures includes four predefined combinations for member ends, and an option foruser-defined settings. The predefined combinations (the first four in the following table)automatically set the appropriate support conditions and degrees of freedom. The combinationsare:

The support conditions of a member end can be:

Combination

Supportcondition

TranslationalDOFs

RotationalDOFs

Supported Fixed Fixed

Supported Fixed Pinned

Connected Fixed Fixed

Connected Fixed Pinned

Use this option to define your own settings for the supportsand connections at member ends. You can use springs andalmost any combination of degrees of freedom.

To ensure that the part remains stable, and that all loads applied to it passthrough to the other structures, avoid using combinations with too manydegrees of freedom.


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Displacementsand rotations

U denotes translational degrees of freedom (displacement). R denotes rotational degrees offreedom (rotation). Define the degrees of freedom in the global coordinate system. The options

are:

See also Support conditions (p. 14)


Analysis part properties (p. 55)

Support condition symbols

Tekla Structures displays symbols for nodes that indicate the support conditions of a node.

Option Description

Connected Member end is connectedto an intermediate analysisnode (another part).

Indicate degrees offreedom for the node.

Supported Member end is theultimate support for asuperstructure (forexample, the foot of acolumn in a frame).

Indicate degrees offreedom for the support.

Option More information

Free Only applies to translational degrees of freedom.

Pinned Only applies to rotational degrees of freedom.

Fixed

Spring Enter translational and rotational spring constants.The units Tekla Structures uses depend on the

programs unit settings.

Partial release Only applies to rotational degrees of freedom.

Use to specify the degree of connectivity, if it isbetween fixed and pinned. Enter a value between 0(fixed) and 1 (pinned).


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Symbol Support condition

No supports

Pinned connection

Fixed connection

Translational direction fixed

Translational direction spring


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See also Support conditions (p. 14)

Defining support conditions (p. 15)

Analyzing composite beams

Composite beams consist of a beam and studs, with a concrete slab on top of the beam. You candefine the analysis properties of the slabs in composite beams, and define the width of the slabmanually or automatically.

To define the properties of the concrete slab in a composite beam:

1. Open the Beam Analysis Properties dialog box and go to the Composite tab.

2. Select the Composite beam option in the Composite beam list.

3. Select a Material and enter the Thickness of the slab.

4. To define the effective slab width:

Manual method: Select the To the left from the beam and/orTo the right of thebeam option button and enter a value in the field next to these buttons. See alsoManual method - limitations (p. 19).

Automatic method: For the left and right side, select the Automatic, half of spanlength divided by option button and enter a value in the field next to these buttons.When you run the analysis, Tekla Structures calculates the effective slab width bydividing the span length of the beam by the value you enter.

See also Viewing analysis results (p. 18)

Viewing analysis resultsTo view the analysis results for composite beams, right-click the beam and select Inquire on the

pop-up menu. The analysis results include:

Element and node IDs

Effective width

Slab thickness

Slab material

Concrete strength

Rib width and height

Rotational fixed

Rotational spring

Symbol Support condition


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Stud diameter and length

Manual method - limitations

Effective width cannot exceed the distance to the nearest beam.

Effective width cannot be more than half the distance to the nearest composite beam.

If there is no beam on either side of the composite beam, the slab width is zero. Use theAutomatic composite beam option to have Tekla Structures calculate the slab width.

Design information

Use the Design tab in the part properties dialog boxes to view and modify the design propertiesof individual parts in an analysis model. Design properties are properties which can vary,according to the design code and the material of the main part (for example, design settings,factors, and limits).

The properties you see when you first open the dialog box are the properties that apply to theentire analysis model you have selected in the Analysis & Design Models dialog box. See alsoDesign codes and methods (p. 65).

To set different design properties for specific parts, modify the values in the appropriateanalysis part properties dialog box.

For example, if the analysis model contains parts with different material grades, define themost common material grade using the analysis model properties. Then change the materialgrade of specific parts using the appropriate analysis part properties dialog box.

To omit individual members from the design check when you run the analysis, set the following

properties to No:


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Steel parts: Check design - Enable design check of member

Concrete parts: Calculate required area - Enable design check of member


Defining buckling lengths (columns) (p. 24)

Effective buckling length (p. 24)Kmode options (p. 25)

Member position

Location ofmember axes

The locations of the member axes of parts define where the analysis members actually meet,and their length in the analysis model. They also affect where Tekla Structures creates nodes.See Members, bars and area objects (p. 10) and A closer look at the analysis model (p. 26).

Use the options in the Axis list on the Position tab in the analysis part properties dialog boxesto define the member axis location of individual parts for analysis purposes. The options are:

Tekla Structures uses the options above for each part when you select the Model default optionfor the member axis location in the analysis model properties. See New... (p. 77) and Memberaxis (p. 61).

Keeping axisposition

Use the options in the Keep axis position list to define whether the axis position is changedaccording to changes in the physical model. The options are:

Option Description

Neutral axis The neutral axis is the member axis for this part.The location of the member axis changes if the

profile of the part changes.

Reference axis The part reference line is the member axis for thispart. See also Part handles.

Reference axis(eccentricity byneutral axis)

The part reference line is the member axis for thispart. The location of the neutral axis defines axiseccentricity.

Top plane The member axis is bound to the top plane.

Middle plane The member axis is bound to the middle plane.

Bottom plane The member axis is bound to the bottom plane.

Left plane The member axis is bound to the left plane.

Right plane The member axis is bound to the right plane.

Middle plane (of left/

right)

The member axis is bound to the middle plane ofleft/right.

If you select the Neutral axis option, Tekla Structures takes the partlocation and end offsets into account when it creates nodes. See Endoffsets. If you select either of the Reference axis options, TeklaStructures creates nodes at part handles.


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Connectivity Use the Connectivity options to define the snapping conditions.

Bound memberlocation

Use the options in Axis modifier X,Y and Z to define whether the member location is bound toglobal coordinates, grid line or neither. The options are:

Offset Use the Offset X,Y and Z boxes to define the member location in global coordinates.

Use the options in the Longitudinal offset mode list to define if the part end offsets of thephysical part are considered when Tekla Structures creates the analysis part. For moreinformation see Analysis part properties (p. 55).


Analysis member of fsets

Use offsets at the ends of analysis members to shorten or lengthen members in their local xdirections, for analysis purposes and to take the eccentricity effects into account.

For example, if a beam only actually spans the clear distance between two supporting columns,you can use offsets to only include the clear distance in the analysis, instead of the distance

between the center points of the columns.

Another example is an eccentric connection between a precast concrete column and beam. To

take the eccentricity of the load from the beam into account, use the analysis offsets of thebeam.

Option Description

No The axis is free to move when snapping end positions tonearby objects. Use this option for secondary members.

Partial - keep in major

direction

The axis is free to move partially, but the member is not moved

in major direction.

Partial - keep in minor

direction

The axis is free to move partially, but the member is not movedin minor direction.

Yes The axis are not moved, but end positions can move along axis(thus extending or shortening the member).

Yes - Keep end

positions also

The axis and the end positions of the member are not changed.

Option DescriptionAutomatic The member snaps or connects with rigid

links to other members.

Manual The member does not snap or connect withrigid links to other members. Automaticconnectivity to other members is createdonly if the member position matches exactlythe other member.

Option Description

None The member location is not bound.

Fixed coordinate The member location is bound to thecoordinate you enter in the X,Y orZ box.

Nearest grid The member is bound to the nearest grid line(the snap zone is 1000 mm).


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Use the Bar attributes tab in the analysis part properties or connection dialog boxes to definethe offset at each end of a member. For more information, see Analysis part properties (p. 55).


Analysis part properties (p. 55)

Analysis properties of components

Use the Analysis tab in the connection or detail dialog boxes to define how Tekla Structureshandles connections and details in the analysis.

The analysis properties of connections and details are:


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Analysis propert ies of s lab componentsUse the Analysis tab in the Slab generation with polygon plate (61) and Slab generationwith points (62) dialog boxes to define the analysis properties of parts created using thesecomponents.

The following table lists the analysis properties of slab components. The option you select inthe Analysis type list box limits the other properties you can define (see the Only use forcolumn).

Property Description

Use analysis

restraints

Set toYes to use the analysis properties of theconnection or detail in the analysis, instead of theanalysis properties of the parts in the connection.

You must also selectYes in the Member endrelease method by connection list box in theAnalysis Model Properties dialog box when youcreate the analysis model. See Member endconnectivity (p. 62).

Member selection Use to associate the analysis properties with eachconnection part (Primary, 1. secondary, 2.secondary, etc.).

Restraint

combination

See Support conditions (p. 14) and Definingsupport conditions (p. 15).

Support condition

Longitudinalmember offset See Analysis member offsets (p. 21).

Analysis profile Tekla Structures uses this profile in the analysis,instead of the one in the physical model, in order totake the stiffness of the connection or detail intoaccount.

Analysis profile

length

This means that in the analysis, Tekla Structuresoverrides the profile of the part in the physicalmodel, for this length.

Property DescriptionOnly usefor

Analysis type How Tekla Structures analyzes the slabs.

Ignore: Slabs are not analyzed.

Beam: Analyze each slab as a beam.

Plate: Analyze each slab as a plate.

Rigid diaphragm: Analyze slabs as arigid diaphragm.

See also Member analysis class (p. 12).

Beam axis The location of the beam axis. See alsoMember position (p. 20).

Beam

Restraints The support conditions of beam ends. The

options are Pinned and Fixed.

Beam


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Properties of in termediate members

When creating an analysis model, Tekla Structures may need to produce more than one analysismember for each physical part. This can result in intermediate members and member ends.

Tekla Structures determines the analysis properties of intermediate members as follows:

1. The member analysis type and member axis location of the analysis members are the sameas of the original part.

2. The analysis offsets of the part ends apply to the corresponding analysis member ends.

Intermediate member ends do not have analysis offsets.3. The support conditions of all intermediate member ends are Connected. The translational

and rotational degrees of freedom are all Fixed. This reflects the nature of the physicalpart, which is a continuous length.

4. The effective buckling length of each analysis member is K*L. K is the length factor forbuckling. L is length, a value described by the Kmode design property. For moreinformation, see Defining buckling lengths (columns) (p. 24).

5. The other design properties are the same for the analysis members as for the original part.


Defining buckling lengths (columns)

Tekla Structures allows you to define buckling lengths for column segments, which representthe building levels. Tekla Structures automatically divides columns into segments at the pointwhere a support in the buckling direction exists, or where the column profile changes.

See also Effective buckling length (p. 24)

Kmode options (p. 25)

Effective buckling lengthEffective buckling length is K*L, where K is the length factor and L is the buckling length. Tocalculate a parts effective buckling length:

1. Open the analysis part properties dialog box and go to the Design tab.

Plate plane The plane on which to create the elementsand nodes. If you select Top plane, TeklaStructures creates the elements on the topsurface of the slab.

Plate

Element type The shape of the elements. Plate

Element size x and y: The approximate dimensions of theelements, in the local x and y direction ofthe slab. For triangular elements, theapproximate dimensions of the bounding

box around each element.

Holes: The approximate size of theelements around openings.

Plate

Filter Nodes that belong to a part matching thefilter will be connected to the rigiddiaphragm. For example, you can use

column_filterto connect only columnnodes to rigid diaphragms.

Rigiddiaphragm

Property DescriptionOnly usefor


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2. Select an option forKmode. For more information about the available options, see Kmodeoptions (p. 25).

3. Enter one or more values in the K - Length factor for buckling field. The number ofvalues you can enter depends on the option you selected in the Kmode field. For multiplevalues:

Enter a value for each column segment starting with the lowest segment, and

Use spaces to separate multiple values:

You can also use multiplication to repeat factors, for example, 3*2.00.

4. Go to the L - Buckling length field:

To automatically calculate length values, leave the fields blank.

To override one or more length values, enter values in the relevant buckling lengthfields. The number of values you need to enter depends on the option you selected inthe Kmode field. You can use multiplication to repeat buckling lengths, for example,3*4000.

5. Create the analysis model and use the Tools > Inquire > Object command on a part. TheInquire Object dialog box opens and displays the member number and the effective

buckling length for each segment:

Kmode optionsUse the Kmode options to define how Tekla Structures calculates buckling lengths. Theoptions are:

Option Description

Physical member L is the length of the column.

Column segment L is the length of one column segment.

Column segment,

multiple values

L is the length of one column segment withuser-defined factors and lengths for eachcolumn segment.


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1.3 Analysis information and settings

This section generally discusses the analysis process and describes analysis settings.

Topics A closer look at the analysis model (p. 26)

Loads in analysis (p. 28)

Load modeling code (p. 29)

Analysis method (p. 30)

A c loser look at the analysis model

This section gives detailed information on how Tekla Structures creates analysis models ofphysical models.

See also Objects (p. 27)

Analytical member L is the length of the member in the analysismodel.

Analytical member,

multiple values

L is the length of the member in the analysismodel with user-defined factors and lengths for

each member.

Option Description

The methods used to create a physical model affect the analysis model.Because of this, you may need to try different modeling methods andanalysis model properties in order to create an accurate analysis modelof a complex physical model.


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Nodes connecting members and elements (p. 27)

ObjectsTekla Structures ignores the following objects in the analysis, even if you have included themin the analysis model (see Objects in an analysis model (p. 60)):

Parts and loads that are filtered out (see Analysis model filter (p. 61)) Component objects (minor parts, bolts, reinforcing bars, etc.)

Parts with the Ignore setting (see Member analysis class (p. 12))

Truss members Tekla Structures does not split members with the Truss, Tension only, orCompression onlysetting (truss members) when two or more truss members intersect with a normal member orwith another truss member.

Nodes connecting members and elementsTekla Structures first creates analysis nodes:

On member axes at the ends of parts

At the intersection points of member axes At the corners of elements

Tekla Structures then checks if the analysis members have common nodes.

Tekla Structures creates common nodes for members if a connection exists between themembers.

Element nodes This is how Tekla Structures creates nodes when plates connect with other parts:

Node colors The color of the node shows the status of the connectivity of the node and whether the node hasbeen selected.

Connected part Action

Beam Tekla Structures splits the beam and creates nodes in it

at the element corners.Column Tekla Structures creates a node at the column.

Another plate Tekla Structures creates the analysis elements so thatthe plates have common nodes on the edges of the

plates.


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Loads in analysis

These are the principles that Tekla Structures follows when it processes loads in the physicalmodel to create analysis model loads.

You define which loads are included in the analysis model. Tekla Structures applies these loads

to members and elements, based on each loads part name or selection filtering criteria,bounding box, and load panel properties. See Applying loads to parts (p. 40) and Modifyingload distribution (p. 41).

In load decomposition, the parts to which a load is applied are projected to the load plane. Theload is then applied to these parts according to the load panel properties, of which the loadsspanning properties and distance from each part are most important.

Point loads A point load is applied to the nearest node, or member or element location. If the point load isnot located directly on any of these, it may either snap to the nearest location or it may be splitinto several loads, depending on the filtering criteria, bounding box, and load panel properties.

Node colorConnectivitystatus Selection Example

Magenta Disconnected Selected

Magenta Disconnected Not selected

Green Connected Selected

Green Connected Not selected


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Line loads A line load is transferred to members and elements that are inside the bounding box of the lineload, and that match the part name or selection filtering criteria of the load. In special cases theline load may be decomposed to point loads if it is not perpendicular to the part it is applied to.If several members receive the load, the load is distributed based on the length of each memberand the distance between the load and member.

Area and uniform

loads

Area loads are decomposed to line loads, and in special cases to point loads if they are not

perpendicular to the part they are applied to. These decomposed loads are then applied tomembers and elements. Members inside the bounding box of the load and that match the partname or selection filtering criteria receive the load. Load panel properties, especially single ordouble spanning and spanning direction, also affect load decomposition.

Nodal load Tekla Structures binds loads to nodes or members in the analysis model. A load is a nodal loadif:

It is between two nodes and the distance to the nearest node is less than 110 mm.

It is not between two nodes (even outside the member) but inside the bounding box andmeets the part name or selection filtering criteria.

Nodal loads do not cause parts to bend.

Member load If a load does not meet the criteria for the nodal load, it is a member load. Member loads liealong the length of the member and cause member deformations.

Other loads Temperature loads are like line loads which affect an entire member. The left, right, top, andbottom surfaces of the member a temperature load affects define the direction of the load.

Load modeling code

Use the Options dialog box to determine the building code and safety factors Tekla Structuresuses in load combination.

1. Click Tools > Options > Options... > Load modeling.

2. Go to the Current code tab.3. Select the code in the Load modeling code list box.

4. Change load combination factors on the appropriate tab if needed:

Tab Description More information

Current code The code to follow in analysisand load combination.


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Loads

2 Loads

Introduction Once you have modeled physical structures by creating parts you can start adding loads. InTekla Structures, you can create point loads, line loads, area loads with uniform or variabledistribution. You can also model temperature, wind, and seismic loads. Either attach loads tospecific parts or to locations.

In this chapter This chapter explains how to create and group loads. It also includes a general description ofload groups, load types, and load properties. Load reference (p. 45) contains step-by-stepinstructions for all load commands.

Assumedbackground

We assume that you have created a Tekla Structures model and have a basic understanding ofmodeling.

Contents This chapter is divided into the following sections:

Basics (p. 31)

Grouping loads (p. 32)

Load types and properties (p. 35)

Distributing loads (p. 39)

Working with loads (p. 42)

Load reference (p. 45)

2.1 BasicsThis section presents some Tekla Structures vocabulary and concepts to help you start to modelloads.

Load model A l oad modelis the portion of the Tekla Structures model that includes all loads, together withthe load group and building code information related to them. Each load in a load model has to

belong to a load group. Each load can only belong to one load group. A load group can containone or more loads.

Load group A l oad groupis a set of loads that are treated alike during load combination. Load groupsshould contain loads caused by the same action and to which you want to refer collectively.Tekla Structures assumes that all loads in a group:


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Loads

Have the same partial safety and other combination factors

Have the same action direction

Occur at the same time and all together

See Grouping loads (p. 32) and Load combination (p. 66).

You need to create load groups because the same action can cause different types of loads, for

example, point loads and area loads. See Load types (p. 36). You can include as many loads asyou like in a load group, of any load type.

Working withloads

In Tekla Structures, you can attach each load to a part for modeling purposes. You can alsocreate floating loads that are bound to locations rather than parts. See Attaching loads to partsor locations (p. 39).

Use the loads bounding box and part name filter or a selection filter to define which parts carrythe load. See Applying loads to parts (p. 40).

Topics Automatic loads and load groups (p. 32)

Automatic loads and load groups

Self-weight Tekla Structures automatically calculates the self-weight of structural parts using the density ofthe material and the dimensions of the part.

To automatically include the self-weight of parts in load combinations, select the Include self-weight check box when you create load combinations. See Creating load combinations (p.68).

Wind loads Use the Wind load generator (28) tool to define the effects of wind on a structure. See CreateWind Load (p. 52).

Seismic loads To automatically include seismic loads in the x and y directions in load combinations:

1. Define the code to follow in the seismic analysis.

2. Define the load groups to include in the seismic analysis and their factors.

For more information, see Seismic analysis (p. 63).

See also Load combination types (p. 67)

Attaching loads to parts or locations (p. 39)

2.2 Grouping loads

Load groups should contain loads caused by the same action and to which you want to refer

collectively. Tekla Structures assumes that all loads in a group:

Have the same partial safety and other combination factors

Have the same action direction

Occur at the same time and all together

Topics Load group properties (p. 33)

Load group compatibility (p. 33)

Working with load groups (p. 34)


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Loads

Load group properties

To define the properties of a load group, click the Load groups icon on the Loads andAnalysis toolbar to open the Load Groups dialog box. The properties are:

Current When you apply loads in the model, Tekla Structures applies the Current load group. You can

only define one load group as Current.

Name Each load group must have a unique name. Use load group names to define the visibility andselectability of loads. For example, you can select, modify, or hide loads based on their loadgroup. See Filtering objects.

Type The type of a load group is the type of action that causes the loads.

Actions causing loads are building code specific. See Load modeling code (p. 29). Mostbuilding codes use some or all of the following actions and load group types:

Permanent, dead, and/or prestressing loads

Live, imposed, traffic, and/or crane loads

Snow loads

Wind loads

Temperature loads

Accidental and/or earthquake loads

Imperfection loads

Direction The direction of a load group is the global direction of the action that causes the loads.Individual loads in a load group retain their own magnitudes in the global or local x, y, and zdirections. See also Load magnitude (p. 38).

Load group direction affects which loads Tekla Structures combines in load combination:

z direction groups are combined with both x and y direction groups.

x or y direction groups are not combined with each other.

Color Use different colors for different load groups.

See also Load Groups... (p. 45)

Load group compatibility (p. 33)


Load group compatibility

When Tekla Structures creates load combinations for structural analysis, it follows the buildingcode you select in Tools > Options > Options... > Load modeling. See Load modeling code(p. 29) and Load combination (p. 66).

To accurately combine loads which have the same load group type, you need to identify whichload groups:

Can occur at the same time (are compatible)

Exclude each other (are incompatible)

Tekla Structures automatically determines and applies the self-weight ofparts. See Automatic loads and load groups (p. 32).


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Loads

To define load group compatibility, clickLoad groups icon on the Loads and Analysistoolbar to open the Load Groups dialog box. Enter numbers to indicate compatibility.

Compatibility Compatible load groups can act together or separately. They can actually be one single loading,for example, a live loading that needs to be split in parts acting on different spans of acontinuous beam. Tekla Structures then includes none, one, several, or all of the compatibleload groups in a load combination.

Incompatibility Incompatible load groups always exclude each other. They cannot occur at the same time. Forexample, a wind loading from the x direction is incompatible with a wind loading from the ydirection. In load combination Tekla Structures only takes into account one load group in anincompatible grouping at a time.



Working with load groups

Use the Load groups dialog box to view, define, modify, and delete load groups. For example,this is where you set load group properties and indicate load group compatibility.

Click the Load groups icon on the Loads and Analysis toolbar to open the dialog box:

Checking loads and load groupsTo find out which load group a load belongs to, select the load in the model and click the Loadgroups by loads button. Tekla Structures highlights the load group in the dialog box.

Tekla Structures automatically applies basic compatibility facts, such asself-weight being compatible with all other loads, or live loads beingcompatible with wind load.

Tekla Structures does not combine loads in the x direction with those inthe y direction.

Compatibility indicators are all 0 by default. It indicates that TeklaStructures combines the load groups as defined in the building code.

Load group types vary according to the code defined in Tools > Options> Options... > Load modeling. If you have to change the code during a

project, you will also need to change the load group types and check loadcombinations.


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Loads

To find out which loads belong to a load group, select the load group in the dialog box and clickthe Loads by load groups button. The associated loads are highlighted in the model.

If you have many loads in the model, you can show the group name and magnitude in themodel view by right-clicking a load and selecting Inquire from the pop-up menu. TeklaStructures also highlights the parts that carry this load.

Changing the load groupTo move a load to a different load group, select the load in the model, then select a load groupin the dialog box and click the Change load group button.

Importing and exporting load groupsTo use the same load groups in other models, you can import and export load groups.

Right-click on a load group in the Load Groups dialog box and select Export... from thepop-up menu to allow the load group to be used in other models.

Right-click on the load group list in the Load Groups dialog box and select Import... fromthe pop-up menu to use load groups from another model.


2.3 Load types and properties

Introduction Each load has a type and properties which define it (e.g. magnitude, direction, and distribution).This section describes the different load types and the properties of each load type.

Use the load properties dialog box to view or modify the properties of a load. ClickAnalysis >Properties > Loads and select a load type to open its properties dialog box.

Filtering byproperties

You can use load types and groups in filters. For example, you can select, modify, or hide loadsbased on their type and load group. See Filtering objects.

Topics Load types (p. 36)


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Loads

Load forms (p. 37)

Load magnitude (p. 38)

Temperature loads and strain (p. 39)

See also Grouping loads (p. 32)

Distributing loads (p. 39)

Load types

Tekla Structures includes the following load types:

Uniform load

Area load

Point load

Line loads


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Loads

Load forms

Distributed loads (line and area loads) can have different load forms.

Line load The load form of a line load defines how the load magnitude varies along the loaded length.

The options are:

Load type Description

Point load A concentrated force or bending moment thatcan be attached to a part.

Line load A linearly-distributed force or torsion. By

default it runs from a point to another point.You can also create a line load with offsets fromthe points. A line load can be attached to a part.Its magnitude can vary linearly across theloaded length.

Area load A linearly-distributed force bounded by atriangle or quadrangle. You do not have to bindthe boundary of the area to parts. Area loadscan have openings.

Uniform load A uniformly-distributed force bounded by apolygon. Uniform loads can have openings.You do not have to bind the polygon to parts.

Wind load An area load that can be defined for zones in thestructure.

Temperature load A uniform change in temperature, that isapplied to specified parts, and that causesaxial elongation in parts.

A temperature difference between twosurfaces of a part that causes the part to

bend.

Strain An initial axial elongation or shrinkage of apart.

To ensure that load analysis is correct, use area and uniform loads forloads on floors. For example, when the layout of beams changes, TeklaStructures recalculates the loads to the beams. It will not do this if youuse point or line loads on individual beams.

Option Description

The load magnitude is uniform across the loadedlength.

The load has different magnitudes at the ends of theloaded length. The magnitude changes linearly

between the ends.


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Loads

Temperature loads and strain

Temperature loads can be caused by:

An increase or decrease in temperature

A difference in temperature between the top and bottom surfaces of a part

A difference in temperature between the sides of a partTemperature changes cause axial elongation or uniform volume expansion in parts.

Different surface temperatures cause parts to bend.

Strain Strain is an initial axial elongation (+) or shrinkage (-) of a part.

To define the temperature loads and strain that affect parts, clickAnalysis > Properties >Loads > Temperature Load... and use the Magnitude tab.

See also Create Temperature Load (p. 51)

2.4 Distributing loads

This section explains how to attach loads and how to define which parts, or lengths and areas ofparts, carry loads.

Topics Attaching loads to parts or locations (p. 39)

Applying loads to parts (p. 40)

Loaded length or area (p. 41)

Attaching loads to parts or locat ions

You can attach loads to parts or locations for modeling purposes.

Attaching a load to a part binds the load and the part together in the model. If the part is moved,copied, deleted, etc., it affects the load. For example, a prestressing load moves with the part towhich it is attached, and disappears if the part is deleted.

If you do not attach a load to a part, Tekla Structures fixes the load to the position(s) you pickwhen you create the load.

To attach a load to parts or locations, open the load properties dialog box. On the Distributiontab, select an option in the Load attachment list box:

Option DescriptionAttach to member Attaches the load to a specific part. If the part is

moved, copied, deleted, etc., it affects the load.

Dont attach The load is not attached but it is considered afloating load. This load is bound to the positionyou pick when you create the load, not to parts.

If you select the Attach to memberoption, you must select the partbefore picking the position for the load.


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Loads

To define which parts carry a load, see Applying loads to parts (p. 40).

Applying loads to parts

In order to apply loads in the structural analysis model, Tekla Structures searches for parts in

the areas that you specify. For each load, you can define the load-bearing parts by name orselection filter, and the search area. To do this, open the loads properties dialog box and clickthe Distribution tab.

Load-bearingparts

To define the load-bearing parts by name:

1. In the Load-bearing parts list box:

Select Include parts by name to define the parts that carry the load.

Select Exclude parts by name to define the parts that do not carry the load.

2. Enter the part names.

To define the load-bearing parts by selection filter:

1. In the Load-bearing parts list box:

Select Include parts by filterto define the parts that carry the load.

Select Exclude parts by filterto define the parts that do not carry the load.

2. Select the selection filter in the second list box.

For more information on selection filters and filtering, see Filtering objects.

Bounding box Use the loads bounding boxto define the area to search for the parts that carry the load. Thebounding box is the volume around the load that Tekla Structures searches for load-bearingparts.

You can use wildcards when listing the part names. See Wildcards.


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Loads

Each load has its own bounding box. You can define the dimensions of a bounding box in the x,y, and z directions of the current work plane. The dimensions are measured from the reference

point, line, or area of the load. See also Handles (p. 43).

Offset distances from the reference line or area do not affect the size of the bounding box. SeeLoaded length or area (p. 41).

See also Each loads load panel properties also affect which parts receive the load. See Modifying loaddistribution (p. 41).

Loaded length or area

If a line, area, or uniform load affects a length or area which is difficult to select in the model,select one close to it. Then use the values in the Distances fields in the load properties dialog

boxes to pinpoint the length or area. You can shorten or divide the loaded length, and enlarge orreduce the loaded area.

Line load To shorten or divide the length of a line load, enter positive values fora and b.

Area load To enlarge the area an area load affects, enter a positive value fora. To reduce the area, enter anegative value.

Modifying load distribution

By default, Tekla Structures distributes loads using the panel method. To modify the way loadsare distributed, modify the properties on the Load panel tab in the load properties dialog box.The properties are:


Spanning Single: in the direction of the primary axis only

Double: along the primary and secondary axes

Primary axis direction IfSpanning is set to Single, you can define theprimary axis direction by selecting a part in themodel and setting this option to Parallel to part orPerpendicular to part.

To manually define the primary axis weight whenSpanning is set to Double, you must also definethe primary axis direction.

Automatic primary

axis weight

Yes: Tekla Structures automatically calculates theload portions for primary and secondary directions.

No: Enter the weight for the primary direction inthe Weight field. Tekla Structures calculates theweight for the secondary direction by subtracting

this value from 1.


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Loads

Example When using double spanning, automatic primary axis weight and the weight value affect theproportions of the load which is applied to the primary axis and to the perpendicular axis.

IfAutomatic primary axis weight isYes, the proportions will be in proportion to the thirdpower of the span lengths in these two directions, i.e. the shorter the span, the bigger the

proportion of the load. The Weight value does not matter.

IfAutomatic primary axis weight is No, the given Weight value (0.50 in this example) is

used to divide the load.

2.5 Working with loads

To modify the properties of a load, double-click it in the model to open the relevant loadproperties dialog box.

When you have finished, clickModify to update the properties of the load in the model.

Topics Changing loaded length or area (p. 43)

Scaling loads in model views (p. 43)

Defining varying wind loads (p. 44)

Load dispersion angle The angle by which the load is projected onto thesurrounding elements.

Use continuousstructure load

distribution

Yes: for uniform loads on continuous slabs. For thefirst and last spans, the distribution of support

reactions is 3/8 and 5/8, instead of 1/2 and 1/2.

No



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Loads

Changing loaded length or area

As well as changing load properties, you can modify loads by:

Moving line load ends

Moving uniform load corners

Changing the shape of openings in loads Adding corners to uniform loads

Handles Tekla Structures indicates the ends and corners of line, area, and uniform loads using handles.When you select a load, the handles are magenta.

You can use these handles to move load ends and corners:

1. Select the load to display its handles.

2. Click the handle you want to move. Tekla Structures highlights the handle.

3. Move the handle(s) like any other object. See Moving an object. If you have Drag anddrop on, just drag the handle to a new position. See Moving an object using drag-and-drop.

To add corners to uniform loads, use the Modify Polygon Shape command. See Modifying

the shape of a polygon.

Scaling loads in model views

You can have Tekla Structures scale loads when you are modeling. This ensures that loads arenot too small to see, or so large that they hide the structure.

To scale loads in model views, clickTools > Options > Options... > Load modeling and go tothe Arrow length tab:


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Loads

Example You define that point loads with magnitude of 1 kN or less are 250 mm high in the model, andpoint loads with magnitude of 10 kN or more are 2500 mm high. Tekla Structures linearlyscales all point loads that have a magnitudes between 1 kN and 10 kN between 250 mm and2500 mm.

Defining varying wind loads

The Create Wind Load (p. 52) command allows you to define which zones have concentratedwind load. Each zone is the height of the wall. Define the width of the zone using eitherdimensions or proportions. You can define up to five zones for each wall.

In the example below, the loads in the global x direction are multiplied by 3 at both corners ofwall 1.


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Loads

The Wind load generator (28) dialog box contains one tab for each wind direction.

2.6 Load reference

This section consists of the reference pages for the load commands.

To create loads, use the icons on the Loads and Analysis toolbar or select a command from theAnalysis > Loads menu. The following table lists the commands for creating loads and gives ashort description of each one.

Load Groups...

Synopsis This command displays the Load Groups dialog box that you can use to manage load groups.

Command Icon Description

Load Groups... (p. 45) Displays the Load Groups dialog box.

Create Point Load (p.47)

Creates a point load at a pickedposition.

Create Line Load (p.48)

Creates a line load between two pickedpoints.

Create Area Load (p.49)

Creates an area load using three pickedpoints.

Create Uniform Load(p. 50)

Creates a uniformly-distributedpolygonal area load using at least three

picked points.Create Wind Load (p.52)

Creates wind loads on a structure.

Create TemperatureLoad (p. 51)

Defines a temperature change in a part,or a temperature difference betweentwo part surfaces.


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Loads

Description Tekla Structures lists all the existing load groups in the Load Groups dialog box. Use thedialog box to view, define, modify, and delete load groups.

Usage ClickAnalysis > Loads > Load Groups....

To define a new load group:

1. Click Add.2. Select the default load group from the list.

3. Click the load group name to modify it.

4. Click the load group type and select a type from the list box.

5. Click the load group direction to modify it.

6. To indicate compatibility with existing load groups:

In the Compatible column, enter the number you have used for the load groups thatare compatible with this load group.

In the Incompatible column, enter the number you have used for the load groups thatare incompatible with this load group.

7. Click OK to close the dialog box.

To modify an existing load group:

1. Select the load group from the list.

2. Change the name, direction, group type, or compatibility indicators.

3. Click OK to close the dialog box.

To delete a load group:

1. Select the load group from the list.

2. Click Delete.

3. Click OK in the warning dialog box. This also deletes the loads in the load group.

Column Description More information

Current The @ symbol identifies the

current load group. To changethe current load group, select aload group and click the Setcurrent button.

Load group

properties (p. 33)

Name Unique name of the load group.

Type Load group type, based on theaction that causes the loads inthe group.

Direction Direction of the action thatcauses the loads in the loadgroup.

Compatible A number that identifies all theload groups that are compatiblewith each other.

Load groupcompatibility (p. 33)

Incompatible A number that identifies all theload groups that areincompatible with each other.

Color The color that Tekla Structuresuses to show the loads in thegroup.

Load groupproperties (p. 33)


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Loads

To find out which loads belong to a load group:

1. Open the Load Groups dialog box.

2. Select a load group in the dialog box.

3. Click the Loads by load groups button. Tekla Structures highlights the loads in themodel.

To find out which load group a load belongs to:

1. Open the Load Groups dialog box.

2. Select a load in the model.

3. Click the Load groups by loads button. Tekla Structures highlights the load group in thedialog box.

To move a load to a different load group:

1. Select the load in the model.

2. Select a load group in the Load Groups dialog box.

3. Click the Change load group button.

To export load groups:

1. Select the load groups to export in the Load Groups dialog box.

2. Right-click and select Export... from the pop-up menu.

3. In the Export Load Groups dialog box, browse for a folder and enter a name for the loadgroup file.

4. Click OK.

To import load groups:

1. In the Load Groups dialog box, right-click on the load group list and select Import... fromthe pop-up menu.

2. In the Import Load Groups dialog box, browse for the load group files (.lgr) to import.

3. Click OK.

See also Working with load groups (p. 34)

Grouping loads (p. 32)

Create Point Load

Synopsis This command creates a point load at a position you pick.

Preconditions Shift the work plane to create loads perpendicular to sloped parts.

Description Tekla Structures creates the point load using the properties in the Point Load Properties dialogbox. The filename extension of a point load properties file is lm1.

When you delete a load group, Tekla Structures also deletes all the loadsin the load group.

If you try to delete the only load group, Tekla Structures will warn you.At least one load group must exist.

You can include several load groups in one load group file.


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Loads

Usage 1. Double-click the Create point load icon.

2. Enter or modify the load properties.

3. Click Apply orOK to save the properties.

4. If you have selected the Attach to memberoption, select the part to attach the load to.

5. Pick the position of the load.

See also Points

Creating a point

Using commands

Create Line Load

Synopsis This command creates a line load between two picked points.

Preconditions Shift the work plane to create loads perpendicular to sloped parts.

Description Tekla Structures creates the line load using the properties in the Line Load Properties dialogbox. The filename extension of a line load properties file is lm2.

Field Description More informati

Documents

Analysis Guide 170 Enu