Question regarding connecting trussed beams to a diaphragm.

[IngDod]

Greetings, I am currently modeling a building in SAP2000 and/or ETABS where I have frames with trussed beams supporting metal decks. My question is: how can I assign a diaphragm to the entire floor that doesn't restraint Z displacements, I was using the "traditional" (rigid) approach, but the resulting diaphragm inhibits the truss behavior of the beams. I think i need to use a Semi-Rigid diaphragm but my trials have been unsuccessful.

I don't want to model the steel deck, i just need a way to transfer horizontal loads (earthquake loads) at the floor level. Specifically, I want to create a joint (connected to the diaphragm)at the center of mass of the level, apply horizontal loads to this joint and have them transferred to other members by the diaphragm. I know that in ETABS (Don't know if this is possible in SAP2000) it is possible to assign a semi-rigid diaphragm based on an area object, however I don't know how to set up the area to not restraint Z displacements.

 

[johnbridge231]

You can do the following:
Select all joints belonging to the level you would like to restraint
Click on Assign->Joint->Diaphragms


Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis

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