Masonry Building Retrofit 1

[Kazzio]

I am starting on a new project, the seismic retrofit design of a 30,0000 sft 3 wythe masonry building (zone 4). I have worked on many brownfield renovation projects in Detroit, so I am not daunted by a facility of this size. I am a bit unfamiliar with modeling this kind of work and would like suggestions. I have a considerable amount of background information concerning the building that was prepaired during the property transaction. I expect present and proposed archtectural drawings in autocad format in about a month. I plan on conducting third party masonry shear (push) tests. Any suggestions on modeling software and design strategies would be appreciated.

 

[Taro]

Get a copy of FEMA 273 (and the new FEMA 356 if you can). This is a valuable resource for seismic retrofit work.

Assuming the existing masonry is unreinforced, the most likely retrofit strategy will be to add new reinforced concrete shear walls or steel concentric braced frames. The benefit of these systems is to stiffen the structure so that large deflections that would damage the masonry are avoided. Shear walls can be conveniently placed by shotcreting against existing masonry walls.

Some historic buildings cannot accomodate new shear walls or braced frames. In these instances, base isolation + dampers is a potential solution (expensive though).