resources for poured gypsum bulb tee roof construction

[teemarie110]

I am looking for resources for poured gypsum bulb tee roof construction. We are doing some renovations to an existing building, built in 1957, and I can’t find the information I need to determine the horizontal diaphragm capacity of the existing roof. The roof construction is 1/2" formboad, with #134 bulb tees @ 24" oc (I think... these old smudged drawings are tough to read!) Reinforcement is galvanized welded wire fabric of #12 wire @ 4" oc across bulb tees and #14 wire @ 8" oc parallel to bulb tees. Any links/tables/articles would be great... thanks!

 

[hokie66]

In 1957, engineers typically did not worry about diaphragm action in roofs of this sort, so I wouldn't expect to find the information you need. If the gypsum was only poured to the top of the bulb tees, I doubt you could depend on much diaphragm action.