![]() ![]() In 2008, an annual earthquake drill known as the Great ShakeOut began in Southern California to teach the basic safety technique of “drop, cover and hold on.” Initially based on a scenario of a magnitude 7.8 quake on the southern end of the mighty San Andreas fault, the drill has since spread across the United States and around the world. Since Northridge there has been a push toward progress - sometimes frustratingly slow - on everything from making buildings safer to increasing society’s overall ability to deal with seismic threats. The damage to hospitals led the state to require strengthening of those buildings. The California Department of Transportation, which had already retrofitted many of the bridges that ended up being damaged, would spend hundreds of millions of dollars to further strengthen numerous bridges identified as being at risk. Vivid images from the quake included scenes of vehicles stranded high on an elevated section of freeway with the road fallen away in front and behind, and the wrecked motorcycle of a police officer who plunged to his death off the end of a broken overpass while rushing to work in the early morning darkness. Some 200 steel-frame high-rises sustained cracked welds. disaster at the time.Īccording to Earthquake Country Alliance, 82,000 residential and commercial units and 5,400 mobile homes were damaged or destroyed, nine parking structures toppled, nine hospitals were evacuated due to structural or other problems, seven key freeway bridges collapsed, and hundreds more were damaged. The widespread damage to buildings, freeways and infrastructure made the Northridge quake the costliest U.S. The catastrophe at Northridge Meadows revealed a particular seismic hazard due to so-called soft-story construction in which a building’s ground level has large open areas for purposes such as parking spots or shop windows. The greatest concentration of deaths occurred at the Northridge Meadows, a 163-unit apartment complex where 16 people were killed when it collapsed onto the parking area below, crushing first-floor apartments. The state said at least 57 died in the earthquake, though a study issued the following year put the death toll at 72, including heart attacks. ![]() The ground shook horizontally and vertically for up to 10 seconds, most strongly in an area 30 miles (48 kilometers) in diameter around LA’s Northridge neighborhood, according to the public-private partnership Earthquake Country Alliance. Most of the energy was released toward mountains that line the northern side of the valley, but there was more than enough energy sent in other directions to cause devastation. The so-called blind thrust fault - one with no surface features to reveal its presence - caused a block of earth to move upward. ![]()
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