It Matters! Are You Prepared?

           One of the many uncertainties expressed by academia, personal line insurers, and homeowners is the ability of residential structures to survive damage from moderate to large earthquakes.  US seismic zones with relatively short recurrence intervals between damaging events have mandated strict building and retrofit codes because the population and infrastructure undergoes damaging ground motions every few decades.  Because no significantly damaging earthquakes have occurred in Mid-America since 1895 (magnitude 6.2, Charleston, MO) and the recurrence interval between damaging events is long (70 to 90 years, magnitude 6.0), most of the residential inventory has not been built to any seismic code and is vulnerable to moderate ground shaking.  Thus, the earthquake damage potential of Mid-America is commonly characterized as “low recurrence, high consequence”.

            Well-established retrofit standards have evolved over the past decade by integration of knowledge gained from the performance of residential structures in the Loma Prieta and Northridge, CA earthquakes.  This information was collected by the Seattle Project Impact Home Retrofit Project Team and was organized into a 3 manual plan set.  The SMARRT manual will incorporate this current West Coast retrofit information.  The digital information will be edited where necessary to better conform to the common framing and foundation construction practices of the Central U.S.  Local building officials and engineers will be consulted for further revisions of SMARRT products.

            Information on the general earthquake hazard faced by Mid-Americans can be found in US Geological Survey Fact Sheet-2006-3125, “Earthquake Hazard in the Heartland”.