Lateral Restraint for a Low Rise RC Bldg

[dcStrucEng]

According to the IBC 2003 (1616.4.1), all structures need to be designed with a lateral force resisting system capable of resisting even the smallest lateral loads (SDC A), either from quake or wind.

I haven't been able to find good guidance for the design of a lateral restraining system for a situation where you have a low-rise (60 ft max), small footprint (60'x60') reinforced concrete flat slab or flat plate building in a low seismic/low wind region.

But, the bottom line is: I need a lateral restraining system, don't I? It seems silly to include concrete shearwalls for such a small building. So can I design the flat slab or flat plate system to work as an ordinary moment frame? If so, are there added detailing requirements needed for the column-slab connections? Added reinforcing steel needed in the columns strips?

The preliminary design of the structure doesn't require many concrete beams (from a gravity loading standpoint), except for around the elevator shaft, stair shaft, and some other openings. So I don't want to add unnecessary structure.

So can my small RC flat slab or flat plate structure be designed as a lateral force resisting system without shearwalls or continuous beams?

Thanks.

 

[frv]

This seems like an odd question.

You certainly have to include a LFRS. You can design it as an equivalent frame system. There are provisions in ACI for the transfer of moments at the column / slab interface. For a flat plate system, make sure you look at punching shear closely.

Also, you have a sway frame, so you will have to design for increased moments. Again, there are provisions for this in ACI.

Do you have more than one elevator / stair shaft? If so, wouldn't it be simpler just to design these as shearwalls?