Indonesia to Build Monumental Suspension Bridge in Ring of Fire
Released: 4/14/2008 12:02:15 PM
California has more than a 99% chance of having a magnitude 6.7 or larger earthquake within the next 30 years, according scientists using a new model to determine the probability of big quakes.
The likelihood of a major quake of magnitude 7.5 or greater in the next 30 years is 46%-and such a quake is most likely to occur in the southern half of the state.
[Editor] At Left: Figure 1. The colors on this California map represent the UCERF probabilities of having a nearby earthquake rupture (within 3 or 4 miles) of magnitude 6.7 or larger in the next 30 years. As shown in the table, the chance of having such an event somewhere in California exceeds 99%. The 30-year probability of an even more powerful quake of magnitude 7.5 or larger is about 46%. [/Editor]
A magnitude 6.8 earthquake struck Japan on 7/16/07, killing 9 and injuring more than 150. The hardest hit areas were near the town of Kashiwazaki, northwest of Tokyo. It triggered mudslides in the town that was already effected by a Typhoon several days before. One of the most newsworthy things about this earthquake is the damage to and minor leakage of radioactive waste and coolant from the world’s largest nuclear power plant in Kashiwazaki. Read on for links and video. (Photo by Kazuhiro Nogi, AFP – Getty Images)
The Claremont tunnel beneath the Berkeley Hills on the east side of Oakland is a water supply tunnel that serves over 800,000 customers in Richmond, Oakland, San Leandro and neighboring communities. One of the unique things about the tunnel is that it crosses the active Hayward Fault. Most of the time when you talk about designing for earthquakes you’re talking about designing to withstand the seismic forces. In this case, the designers needed the water transmission tunnel to withstand up to 7.5-ft of offset due to fault slip and still maintain a minimum level of service. (Photo credit: Sue Bednarz, Jacobs Associates, Inc. by way of Civil Engineering Magazine)
This post describes the relatively recent Claremont Tunnel Seismic Upgrade Project as reported in Civil Engineering Magazine (May 2008, v. 78, no. 5, pp 58-63, 96-97).
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