Modeling Members With Overhangs
Modeling Members With Overhangs
(OP)
Are rigid elements the best way to model simply supported roof purlins overhanging an inclined truss (eg pratt, scissor, etc)? The help file does include some guidance on using rigid elements to represent the offset. My question comes into the correct fixity and trying to capture a realistic simply supported condition. Releasing rigid element i- (top of inclined member) or j-end (bottom of My and Mz at both supports would cause a warning for the members rolling over. One approach I've found is releasing i-end My and Mz in one support and releasing i-end Mx and strong axis (My or Mz depending on orientation) moment at the other support. This leaves an weak axis bending in the connection, which would be counter intuitive for a simply supported connection. Does this connection get designed to resist the weak axis bending? Any thoughts would be appreciated.
RE: Modeling Members With Overhangs
My tendency is to use end releases NOT in the rigid links themselves, but in the simply supported members that frame into them. Most of the time, this is easier in that the orientation of the member's local axis is easiest to understand. I don't think this should lead to instabilities though I may not have your exact situation pictured correctly.