VIEW Q4 2012

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The Quarterly Newsletter for Commercial Real Estate Women | San Francisco

2012: Finishing Strong!

4TH Quarter 2012

Five Common Myths about Building Performance and Business Continuity after an Earthquake in the Bay Area © 2012 Lizzie Blaisdell, S.E., Degenkolb Engineers with Donald Ballantyne, Degenkolb Engineers Through working with clients – building owners, architects, and contractors – we have come to realize that there are common misunderstandings or “myths” regarding building performance and business continuity after an earthquake in the Bay Area. Presented below are the top five most common myths that I have come across here at Degenkolb and why these myths are just not true. Myth 1: My building was designed to Code, so it is earthquake-proof Despite what many people believe, buildings are not designed to be earthquake-proof; they are designed for a minimum level of earthquake resistance deemed adequate to protect life-safety in our communities. Society, through its elected officials, has decided that we should all be safe in a major earthquake, but that we can’t afford to spend the amount of resources necessary to ensure that safety. The minimum forces that engineers use to design buildings in California are prescribed in the California Building Code. In other words, the Code is intended to provide a minimum standard for life-safety; there is no intent

or guarantee that a building designed to the Code will not suffer extensive damage, will be useable after a major earthquake, or even will be economically feasible to repair. The “major” earthquake upon which the Code is based is the largest earthquake that is expected to occur during a 475-year period. The Great San Francisco Earthquake of 1906 was such an earthquake. On a probability basis, there is a 10% chance that every 50 years a larger earthquake might occur, so it is evident that there are even larger earthquakes that the Code does not address. Some new buildings, such as hospitals and other critical facilities, are required by Code to be designed for slightly better performance, i.e., less damage, but even they aren’t earthquake “proof.” Many building owners and occupants do not think much about the earthquake damage that will occur to non-structural components (partitions, utilities, cladding systems, shelving, contents, etc.) in a major earthquake or the risk to lifesafety that these falling objects pose to building occupants. Short of a building collapse, a person is much more likely to be injured in an earthquake by fall-

ing objects than by the structure itself. Non-structural components, including larger contents, are also required by the building code to be anchored or secured to the building structure. But even with that, damage occurs, and this level of performance is far from earthquakeproof. Similar to building design, nonstructural seismic design is intended to protect life and will not necessarily ensure that the components will be useable after an earthquake. The structural engineering industry has the tools to design buildings to higher performance levels with less damage; this approach is called PerformanceBased Design. With Performance-Based Design, the building owners specify a (continued on page 2)

ISSUE HIGHLIGHTS: Russian Connection Restores Historic Windmill {P3} Spotlight on Sponsorship {P5} Offices of Tomorrow and Office Trends {P6} CREW SF Boat Tour Feature {P7} Zynga Headquarters Building Tour {P8} OUR SPONSORS {P10}

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