Seismic Loads for Cranes

[nategemb]

When determining the seismic load for a crane, is it more appropriate to use Chapter 12 or Chapter 13 of ASCE 7? Specifically, we are looking at the seismic force on the clips holding the rails, as well as the seismic lateral load on the crane beams (in this instance it's a bridge crane).

 

[HTURKAK]

Two points;
- All runway beams , rails , supporting bridge , crane own wt , connection wts shall be included in the calculation of effective seismic weight,
- Chapter 13 (SEISMIC DESIGN REQUIREMENTS FOR NONSTRUCTURAL COMPONENTS ) is the applicable section. Pls look also 13.6 MECHANICAL AND ELECTRICAL COMPONENTS.

 

[nategemb]

HTURKAK,

Thanks for the response. I agree with your first point. Your second point is where I've been getting stuck. Table 13.6-1 does not list coefficients for cranes nor do I see anything in 13.6 that references cranes. Perhaps cranes could be considered to fall under "other mechanical or electrical components?" It seems odd to me that a component as significant as a crane isn't specifically addressed.

 

[HTURKAK]

"other mechanical or electrical components?"

Yes. You are expected to use ( Other mechanical or electrical components) and design the connections as per 13.4 NONSTRUCTURAL COMPONENT ANCHORAGE AND ATTACHMENT.