You are in a seismic zone in which ordinary or intermediate moment frames are not permitted, and you are trying to cantilever the columns to hold up a concrete slab? Why would you expect to be allowed to use a system that is LESS robust than ones that you KNOW are disallowed? The way I read...
Concrete filled lally columns are very common in Massachusetts, at least in Eastern MA. Maybe that's because John Lally lived in Waltham. From the beginning of the 20th Century up through at least the 1930s or so, they were made with structural steel pipe. I've replaced many of them that were...
Does anybody know when they stopped making "lally columns" from structural (standard) pipe, concrete filled, and switched to the current 16 GA shells? I am looking at 1987 plans for a building that calls for 3-1/2" lally columns. When I calculate the load, it is more than twice what I would...
It occurs to me that, depending on the exact nature of the fabric roof and its supporting framework, the fabric could sag, and collect more snow load, rather than shedding it, even if sloped. I have not designed many fabric and cable structures, but I recall that second order effects are very...