Truss Design
Truss Design
(OP)
I have a condition in a church that needs me to design a king post steel truss spanning 96' feet. The truss is going to carry a movable wall below and concrete roof tile on top. My coworkers is saying that I could use double angles as truss members. However, I want to know if any of you guys had designed a truss with such a long span. Is it possible to do the truss w/ double angles.
Would RAM Advanse be a good tool to design the truss or is there any other program that could do the truss design?
Would RAM Advanse be a good tool to design the truss or is there any other program that could do the truss design?






RE: Truss Design
RE: Truss Design
As hokie66 noted, you have a lot of options for members, depending on configurations.
As for the analysis, most FEA programs don't handle trusses very well without a lot of care in the modeling. If you do it, be careful with each member's restraint conditions or bracket the extremes, knowing you'll be somewhere in the middle. Welded trusses are more likely to act like an FEA model than other connections, but it isn't usually necessary to develop the moment in such connections. Do as hokie66 suggests...hand calcs and check by program.
RE: Truss Design
RE: Truss Design
RE: Truss Design
RE: Truss Design
i agree, double angles might be a stretch. i used double L8x8 and L8x6 for a 80 long truss, but it's depth was a constant 10 feet so the compression members weren't that long. with a pitched top chord, your web members are going to become quite long.
you might try using W shapes. rotate all truss members so that the strong axis is in the horizontal direction. this provides great out of plane stiffness for compression members, keeps the truss from being wobbly during erection, and allows you to use a variety of member sizes while maintaining good connections. for example: W12x65 top and bottom chords, W12x22 and W12x26 web members. members are bolted together on each side to their flanges b/c they all have relatively same depths (horizontal truss thickness) make sense?