Seismic Response and Retrofit Studies of Selected Steel and Composite Buildings

这是一个事后调查项目，目的是从洛马普里埃塔地震(1989年10月)中吸取工程经验教训。洛马普里塔地震提供了有关工程结构在强烈地面震动下的性能的重要信息。仪器建筑物产生的强震数据提供了一个独特的机会，可以进一步提高对建筑物的地震行为和抵抗力的认识，并为其设计开发改进的方法。本项目选择了三种钢结构和组合建筑结构进行了详细的研究。其中一辆结构受损严重，另一辆摇摆过度，第三辆表现出色。将开展两项主要研究工作。第一种是进行分析计算，利用地下室记录的运动来研究这些建筑物的地震反应，并将分析结果与上层记录的反应相关联。对于严重受损的建筑，还将进行弹塑性时程分析。第二项任务是制定翻新或加固方案，以改善受损建筑物和经历过度动力运动的建筑物的抗震性能。这项研究将基于大地震期间的性能数据，提高对钢结构抗震性能的理解。

This is a post-event investigation project to learn engineering lessons from the Loma Prieta earthquake (October 1989). The Loma Prieta earthquake has produced important information on performance of engineered structures subjected to strong ground shaking. The strong-motion data generated from the instrumented buildings provide a unique opportunity to further advance the knowledge about the seismic behavior and resistance of buildings and to develop improved methodologies for their design. Three steel and composite building structures have been selected for detailed studies in this project. One suffered serious structural damage, another experienced excessive sway motion, and the third showed excellent performance. Two main research tasks will be conducted. The first is to perform analytical calculations to study the seismic response of these buildings using the recorded motions at their basement and to correlate the analytical results with the recorded responses at the upper levels. For the seriously damaged building inelastic time- history analyses will also be carried out. The second task is to develop retrofit or strengthening schemes to improve the seismic performance of the damaged building and the building experiencing excessive dynamic motion. The study will improve the understanding of seismic behavior of steel structures based on the performance data during a major earthquake.