Action > TempVar

Calculation of the equivalent linear strain corresponding to a given non-linear temperature distribution. The temperature distribution is given by a set of reference points with defined temperature value collected in a Reference Set of the type "Temperature points". Results are stored in a specified load set as fixed end forces (load type TB) equivalent to the give temperature distribution. This load set can be addressed in a subsequent load case calculation.

Setting

Description

Action

Code of the selected Action. It is possible to switch to defining an other action without leaving and re-entering the input function.

Action will be skipped (Option)

The action will be skipped in the calculation process if the option is selected.

Input-1 > Reference Set

Name of the reference set containing the temperature points which define the temperature distribution in the cross-section.

Note: Points have to be arranged in the correct sequence (usually top-down). The first point has to be defined as type POINT. Max. 50 points are allowed.

Input-2 > 3D/2D

Option defining whether the full fixed end vector shall be applied, or just normal force + bending in one of the local axis directions.

Setting	Description
3D (empty)	Default. Full vector applied.
My2D	Only bending about y axis considered.
Mz2D	Only bending about z axis considered.

Input-3 > (Gradient only)

Option for excluding the constant part of the equivalent strain.

Setting	Description
empty	Default. Full linear temperature considered. The temperatures defined in the diagram are assumed as temperature differences to an initial temperature where the structure is stress-less.
Grad	Only the temperature gradient is applied.

Input-3 > (Primary State)

Only relevant when the option Include Primary TempVar effects is set in the Recalc pad: Option for relating primary stresses to the actual strain plane or to an artificially modified fictitious primary strain plane defined by the primary stresses of the extreme fibers.

Setting

Description

empty (create primary strain plane)

Default. The program calculates a fictitious primary strain plane defined by the primary stresses of extreme fibers (load type TB0). Primary stresses of any stress points with the respective store option (load type TSTR0) are calculated as the difference to the primary stress defined by the fictitious primary strain plane, such that the total primary stress (due to TB0 and TSTR0) is correct.

Note: This option is in principle obsolete when stress points are defined with the option "Store results for stress-point" where the primary stress is taken properly into account. The option for storing primary stresses for individual stress points has been implemented in July 2011 and this option has been kept as default for compatibility reasons with older program versions.

Stress (create only primary stresses)

The program stores the primary stresses for individual stress points and does not create a fictitious primary strain plane if the option Include Primary TempVar effects is set in the Recalc pad (i.e. internal forces remain correct).

Output-1 > Load Set Name

Name of the Load Set that will be generated to be used in the load case calculation. This Load Set must be initialized prior to this operation.

Output 2 > List File

Output file where the results of this calculation will be documented.

Default: Load-set-name.lst

Delta-T

Duration of the Action (not applicable for this action)

Description

Descriptive text for the selected Action (max. 80 characters)

Non-linear Temperature Distribution

Some design codes require a non-linear variation of the temperature over the cross-section to be investigated. This is for instance the case in the

AASHTO Code, Australian Standard
British Standard BS 5400, Korean Standard

All these Standards only require considering a non-linear variation in the vertical direction. A constant distribution may be assumed for the horizontal direction and may be combined with the non-linear case. This fact has been considered in the program, and therefore only a distribution in the local y-direction can be defined.

Some codes prescribe the temperature state to be investigated as a function of the distance of the point from the upper surface and the bottom surface of the cross-section; other formulations refer to the related distances (with respect to the total cross-section height). Also mixed formulations can occur.

Two cases have usually to be investigated: a temperature increase and a temperature decrease. The required variations for these 2 cases generally differ and 2 separate Load Cases have therefore to be investigated.