Response Modification Factor for diaphragm attachment upgrade at existing tilt up structure?
Response Modification Factor for diaphragm attachment upgrade at existing tilt up structure?
(OP)
We have a precast tilt up structure, seismic design category D. Would you use the current code to determine the R factor for seismic forces for roof diaphragm connections? Current ASCE 7-10 does not allow ordinary precast shear walls in design category D (R=3). The engineer on the project used R=4 for intermediate precast shear walls, but to me this seems un-conservative for an existing building pre-dating intermediate shear walls.






RE: Response Modification Factor for diaphragm attachment upgrade at existing tilt up structure?
Have you read ASCE 41?
"It is imperative Cunth doesn't get his hands on those codes."