can I model a bridge pier with shell elements

[goanga]

I tried to model a bridge pier with shell elements but the results I obtained with SAP2000 from a "QUAKE" load (UBC94) are different from the results obtained from the frame model;

 

[Qshake]

Unless your bridge pier is made of hollow units which have a relatively thin wall thickness (especially steel), I would stay away from the shell elements.

Without going into too much detail, the shell elements are much more complex than the frame elements and in my experience unless you meet the requirements above, it's best to stay with something simplistic that works and is understood.

Most bridges, if not all, can be modelled with fair accuracy using 3D beam elements. I say fair accuracy because more complex bridges will require different arrangements while for regular bridges it works very well.

Regards,
Qshake

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