Hello,
I am modeling a building that has a concrete pan joist system. I model the columns, support beams, pan joists (using the pan joist tool), and slab. I wanted to check my work so i did no apply any external loading, but entered the concrete design tab to check the self weight reactions. When I check the max moment on a joist, I am getting a number that is 2x the expected moment from self weight. I then deselected the slab self weight and got a number that was closer to the expected results, but still a couple k-ft smaller.
I have never used RAM to model concrete before, is there a trick I am missing?
Thanks,
ANdrew
Please refer to: https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/3037/ram-ss-gravity-loads-faq
I understand that the program will count the slab and the overlapping area of the beam in its self weight calculation if the beam is rectangular, but the pan joist command creates t-beams. This is where I am confused, that link says in t-beam self weight calculations the slab is calculated separately from the t-beam. So why do I get an answer that is 2x my expected moment if I include the self weight of the slab?
I would have to see your model to say. Perhaps your flanges overlap? Secure File Upload
I ran a test model in v17.01 with some pan joists and rectangular beams. The difference in the total reactions when using or not using the beam self-weight works out in my case, i.e. it's only the weight of the pan joist stems (and the entire rectangular beam weight) that is applied.