Simulating the Response of High-Rise Buildings to Great and Giant Subduction Earthquakes

这项研究的目标是调查高层建筑在大俯冲地震中的表现。这包括预计将在卡斯卡迪亚俯冲带发生的大地震(Mw9)。不幸的是，这类地震从来没有记录到强烈的地面运动，尽管它们预计会在长时间内丰富并持续很长时间。目前，2003年高知冲8.3级地震是有记录以来最大的俯冲地震；北海道有276个高质量的强震记录。这个研究小组分析了这276个地震动记录，并模拟了它们对根据1994年《统一建筑规范》设计的6层和20层钢框架结构的重要性。虽然在北海道强烈震动的地区没有这样的建筑，但这些模拟表明，如果有高层建筑，那么整个沿海地区都会发生强烈的地震，一些地方有倒塌的可能性。这项为期两年的研究项目的主要重点是扩展现有的关于东京奥基地震的工作，以推断高层建筑在更大震级地震中的表现。提出用经验格林函数技术模拟卡斯卡迪亚俯冲带的一次9级地震。使用2003年的Tokachi-Oki地震作为格林函数的来源，研究小组将模拟2004年苏门答腊岛地震(M 9.2)的强震和远震体波。将密切关注西雅图盆地的长周期波的放大。模拟的地震动将作为钢框架结构非线性分析的输入。这项研究应该对太平洋西北地区高层建筑目前使用的设计程序的充分性进行评估。

The goal of this research is to investigate how high-rise buildings may perform in large subduction earthquakes. This includes giant earthquakes (Mw9) such as are expected on the Cascadia subduction zone. Unfortunately, strong ground motions have never been recorded from such events, although they are expected to be rich in long periods and have long durations. Currently, the M 8.3, 2003 Tokachi-Oki earthquake is the largest well recorded subduction earthquake; 276 high-quality strong motion records are available from Hokkaido Island for this event. This research team has analyzed these 276 ground motion recordings and has simulated their importance to 6- and 20-story steel moment-frame buildings that were designed according to the 1994 Uniform Building Code. Although there were no such buildings in the strongly shaken regions of Hokkaido, these simulations indicate that if there had been high-rise buildings, then they would have been strongly excited throughout the coastal region, with the potential for collapse in some locations.The primary focus of this 2-year research project is to extend the existing work on the Tokachi-Oki earthquake to infer the performance of high-rise buildings in even larger magnitude earthquakes. It is proposed to use the empirical Green's function technique to simulate a M 9 earthquake on the Cascadia subduction zone. Using the 2003 Tokachi-Oki earthquake as source of Green's functions, the research team will simulate both strong motion and teleseismic body waves for the 2004 Sumatran earthquake (M 9.2). Careful attention will be given to the amplification of long period waves in the Seattle basin. Simulated ground motions will be used as inputs to the nonlinear analysis of steel frame buildings. This study should provide an assessment of current the adequacy of current design procedures used for high-rise buildings in the Pacific Northwest.