Earthquake Deformations of Subway Infrastructure

地铁基础设施的地震变形

• 批准号: 9714859
• 负责人: Vincent Lee
• 金额: $ 10万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-10-01 至 1999-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9714859&HistoricalAwards=false
• 关键词: Earthquake; Deformations; Subway; Infrastructure

9714859 Lee Most large metropolitan areas here in the United States, or countries in other parts of the world, already have or are planning to have underground infrastructure systems as an alternate way of urban transportation. It is important to understand the characteristics of damages associated with the underground construction and to find out the cause of both geotechnical as well as structural deformations, and also, to study the influence of local site effects in the vicinity of the structure on the amplification of structural deformations resulting from strong earthquake motions. Experiences from previous earthquakes suggest that the recorded motions in some areas had larger than expected amplitudes. These are usually areas with large depths of alluvial sediments together with comparatively soft soil deposits near the surfaces. Massive civil infrastructures (dams, freeway networks, bridges and now the underground subways) respond to strong earthquake ground motions that are highly dependent on the surface and subsurface topographies at the local sites. This project is to study the effects of the interactions among the subways, the multiple structural foundations and the local geology, to explore how all these key elements will affect the resulting amplifications of foundation motions. The proposed method is based on the wave propagation in elastic solid media. The challenge in solving the problem will be in the boundary conditions where the nonorthogonal compressional and shear potentials are coupled. This will be overcome with expanded series and integral representations of the wave potentials. Results from these studies will be compared with the actual deformations as recorded from previous earthquakes. The comparisons will serve as guidelines to the correct modelling of the problem under consideration. With proper understanding of how surface (buildings and freeways) and subsurface (underground subways) structures performed during str ong-motion earthquakes, future structural design of new buildings and retrofit plans for existing structures can be improved by including these local site effects to provide the correct design strength and reinforcement. Then it will help to minimize property damage and the loss of life in future earthquakes to come. ***

9714859 Lee 美国的大多数大城市地区或世界其他地区的国家已经拥有或计划拥有地下基础设施系统作为城市交通的替代方式。 重要的是要了解与地下建筑相关的损坏特征，找出岩土工程和结构变形的原因，并研究结构附近的局部场地效应对放大的影响。强烈地震引起的结构变形。 以往地震的经验表明，记录到的某些地区的震动幅度比预期的要大。 这些区域通常有较深的冲积沉积物以及靠近地表的相对松软的土壤沉积物。 大型民用基础设施（水坝、高速公路网络、桥梁以及现在的地下地铁）对强烈地震地面运动的响应高度依赖于当地的地表和地下地形。 该项目旨在研究地铁、多重结构基础和当地地质之间相互作用的影响，探索所有这些关键因素将如何影响基础运动的放大。 所提出的方法基于弹性固体介质中的波传播。 解决该问题的挑战在于非正交压缩势和剪切势耦合的边界条件。 这将通过波势的扩展级数和积分表示来克服。 这些研究的结果将与以前地震记录的实际变形进行比较。 这些比较将作为对所考虑的问题进行正确建模的指南。 通过正确了解地面（建筑物和高速公路）和地下（地下地铁）结构在强震期间的表现，可以通过考虑这些当地场地效应来改进新建筑的未来结构设计和现有结构的改造计划，以提供正确的设计强度和加固。 这样，它将有助于最大限度地减少未来地震中的财产损失和生命损失。 ***