huangyhg

risa3d reaction results for wind don't look right
the structure in question is a weldment of plates with stiffeners and multiple columns. in plan view it is a rectangle with the side walls having seven columns and six bays for a total of fourteen columns. the center bay has a large stack supported off the four center columns. if you hand calculate wind and dead loads on the center bay the loads at the base plates would be the largest, but risa3d results is pushing everything to the corners of the weldment on the opposing wall and they are the largest load. has anyone ran into this problem?
i've used risa 3d for years and have a high trust in its performance and accuracy. i would bet you have a modeling issue. one of the best things to do is to always first look at your models deflection as this usually reveals how the model is being interpreted and how the matrix solution is panning out.
per your statement "pushing everything to the corners" ... re
i've also been using risa for 10+ years and every funky result was caused by a misfit model. there was one time that my risa output of a truss with unusual geometry didn't at all match someone else's ramadvanse truss model (the ramadvanse model was giving us 0 force web
thanks for your responses. please don't get me wrong, i have been a fan of risa for quite some time (if anyone re
it's sort of difficult to envision your model. if you can post it on a web-photo sharing site (
are you making a finite element model with plates? i have only used that part of risa once, and that was to analyze a glulam beam that had a huge hole cut in the middle. i bet i put 40 hours into that model. before i cut the hole in the middle, i analyzed the beam by hand and with risa (the typical matrix analysis part of it) and messed around with my plate model until i got results that essentially matched the other, then i cut a hole in it.
unless you really know what you are doing, i think it would really be good idea to first get your model to give you the results you already know and then modify it. also read the help for using plates and make sure you aren't doing anything they tell you not to, like use them for diaphragms. also, the smaller the mesh the better and no triangles.

__________________
借用达朗贝尔的名言：前进吧，你会得到信心!
[url="http://www.dimcax.com"]几何尺寸与公差标准[/url]