» Read more recent posts about seismic calculations, seismic rack designs, and the latest version of ANSI MH16.1.

 

It’s a common misconception that seismically designed rack is only found west of the continental divide. In fact, earthquake activity exists in multiple regions throughout the U.S. This includes the Midwest and Southeast. That’s why, depending on where within the U.S. a facility is located, a seismic force review may be necessary. Therefore, rack manufacturers take a seismic force review into account when engineering, manufacturing, and installing a pallet rack system.

Will My Rack Need A Seismic Force Review?

One of the fastest ways to determine the projected intensity of a potential earthquake in a new rack’s geographic location is to consult the Seismic Maps website (www.seismicmaps.org). By inputting the facility address (or latitude and longitude coordinates), the site shares the seismic parameters of a given location.

Two separate numbers represent the ground acceleration at the site as a percentage of gravity:

Your rack design engineer will use that information as part of the determination of the facility’s seismic design category and design the rack to withstand those anticipated forces accordingly.

Subsequent design decisions are a result of a series of engineering calculations. These increase the safety of any persons in proximity to a rack by reducing the risk of its collapse should an earthquake occur.

MH16.1 Standard Discusses Earthquake Loads

Section 2.6, “Earthquake Loads,” of the ANSI MH16.1-2012 (R2019): Specification for the Design, Testing and Utilization of Industrial Steel Storage Racks, published by RMI, includes a complete listing of the calculations to be performed by a qualified rack design engineer. Considerations include:

Learn More About the Seismic Force Review Process

RMI includes a section on Seismicity in its list of Frequently Asked Questions.