Deflection in Truss Design
Deflection in Truss Design
(OP)
Hello - New to the forum and looking for help! Here's the problem:
I'm helping my brother build a permanent dock (for boats) and want to span as far as possible; shooting for 65' at this point. I have a roof truss design that I believe will be a good starting point except I cannot determine "I" for the geometry. This particular roof truss is made of steel angles on top and bottom (4 total) with ~ 1" diameter wire rod connecting the top two steel angles to the bottom two steel angles (up and down at some angle). Hopefully the design sounds familiar... I can calculate "I" for the steel angles in this particular geometry, but can't get any meaningful information regarding overall stiffness because I don't know how to handle the rod (straight members) in the calculations...
Any help would be appreciated.
I'm helping my brother build a permanent dock (for boats) and want to span as far as possible; shooting for 65' at this point. I have a roof truss design that I believe will be a good starting point except I cannot determine "I" for the geometry. This particular roof truss is made of steel angles on top and bottom (4 total) with ~ 1" diameter wire rod connecting the top two steel angles to the bottom two steel angles (up and down at some angle). Hopefully the design sounds familiar... I can calculate "I" for the steel angles in this particular geometry, but can't get any meaningful information regarding overall stiffness because I don't know how to handle the rod (straight members) in the calculations...
Any help would be appreciated.





RE: Deflection in Truss Design
Example: four each L-2x2x3/8, two top and two bottom with total dpth of 30". Composite I of joist equal 4 times ((1.36 in<2)x(14.4 in x 14.4 in) + 0.479 in<4), or 1130 in<4.
RE: Deflection in Truss Design
With regard to the web, my main concern is buckling - right? I suspect buckling before failing in tension? Is there a preferred method for evaluation of the web? I have an old statics book from college and found the truss section with "method of joints." I must admit - it has been a while since I've had to do anything like this, is there anything online to help? Recommended reading?
RE: Deflection in Truss Design
RE: Deflection in Truss Design
RE: Deflection in Truss Design