Nov 28 2007 2:47PM | Permalink | Email this | Comments (0) |
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The Precast/Prestressed Concrete Institute has released the first edition of Seismic Design of Precast/Prestressed Concrete Structures. The manual represents the first comprehensive guidelines for meeting the requirements of the International Building Code and other engineering standards in regions of varying seismic hazard across the country.

Q: Across the country, you say? Why should a builder in Nashville worry about an earthquake?

A: Ever hear of New Madrid? Probably not unless you’re from the area or you watch too much History Channel (like me). The New Madrid Seismic Zone, also known as the Reelfoot Rift or the New Madrid Fault Line, is a major seismic zone running through Illinois, Missouri, Arkansas, Kentucky and Tennessee.

The fault system was responsible for the 1811-12 New Madrid Earthquake in which three earthquakes of a magnitude of 7.0 or greater struck with great ferocity and left behind catastrophic damage and hundreds of aftershocks. Since 1812 frequent smaller intraplate earthquakes (earthquakes within a tectonic plate) were recorded for the area.
 
Though the guide isn’t a panacea for earthquake prevention, it does satisfy a huge need. “There has never previously been a publication that addressed seismic needs as they related to precast concrete design for all regions across the country and all code requirements,” says Jason Krohn, director of technical activities for PCI. “The manual was created especially because of the number of new provisions impacting seismic design in the last few code cycles.”

According to the PCI, the authors examined various styles and classifications of precast concrete lateral-force-resisting systems and review code and behavior requirements. These requirements are then applied to realistic examples. The manual includes an examination of energy dissipation, ongoing research, diaphragm design and anticipated code developments.