In SAP2000, you can evaluate the effect of warping only by modeling the member that is subjected to warping by shell or solid elements. Members with certain of cross sections (for example I-girders) could be also modeled by a combination of shell elements for the webs and frame elements for the flanges to evaluate warping. You can define section cut to obtain normal stresses due to combined flexure and warping.

SAP2000 does not evaluate warping directly for frame elements and it does not explicitly calculate or use the warping moment of inertia, Iw.

FAQ

How can I obtain warping stresses from SAP2000?

Use shell elements to create a detailed model of the beam.

Can I evaluate warping stresses using only frame element, or do I need to create more detailed model using shell elements?

Modeling by shell elements is requiredWarping may be evaluated in structural members which are modeled using shell or solid objects. Warping is not evaluated directly for frame objects. Further, warping moment of inertia Iw is not explicitly calculated. To characterize local warping within frames, members should be modeled as a combination of shell objects. Wide-flange (W) sections may be modeled this way, for example, when analysis is to consider the warping of flanges. Section cuts may then be defined to obtain normal stresses which result from combined flexure and warping.

How are warping stresses obtained for a beam?

Answer: Warping within a frame object may be analyzed by using a combination of shell objects to model the member.