Support Types in Truss Model - Engissol
Support Types in Truss Model - Engissol
(OP)
Just wondering what support types you guys use when modeling roof trusses? I've been using fixed/roller when solving by hand, but is there a more realistic, or accepted method when using software to model?
Thanks so much for the help.
Thanks so much for the help.






RE: Support Types in Truss Model - Engissol
The horizontal resistance for a roof truss typically comes from the roof diaphragm (under wind or seismic loading, that is).
Hard to model that easily.
RE: Support Types in Truss Model - Engissol
Regards
Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis
http://www.engissol.com/cross-section-analysis-des...
RE: Support Types in Truss Model - Engissol
The majority of common 2x trusses are typically modeled with fixed-roller. Other than special circumstances, such as collector trusses, when would you feel that you would not model it that way?
RE: Support Types in Truss Model - Engissol
BA
RE: Support Types in Truss Model - Engissol
As I said, experience, software knowledge and supervision.
If you think you lack one of those, I can kindly suggest you where to start from.
We are here to help.
Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis
http://www.engissol.com/cross-section-analysis-des...
RE: Support Types in Truss Model - Engissol
@Johnbridge231 - you did not answer my question
RE: Support Types in Truss Model - Engissol
Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis
http://www.engissol.com/cross-section-analysis-des...
RE: Support Types in Truss Model - Engissol
You still did not answer my question.
RE: Support Types in Truss Model - Engissol
As for your question, in order to account for thermal loads and their effect on the truss members, a fixed roller as you suggest is wrong.
Sorry to say that but you wanted to know.
Happy reading and many many regards.
Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis
http://www.engissol.com/cross-section-analysis-des...
RE: Support Types in Truss Model - Engissol
RE: Support Types in Truss Model - Engissol
Design of the roof diaphragm is a separate issue.
BA
RE: Support Types in Truss Model - Engissol
the user can easily assign any type of them at any joint of the truss.
PS: This post is very educational, as it seems that terms like "restraint", "stiffness", "thermal loads" etc. are explained in deep.
RE: Support Types in Truss Model - Engissol
In my experience the goal in design is not to simulate the field conditions as much as it is to find a conservative simplified model.