Near-Source Ground Motion: Probabilistic Prediction of Accelerograms & Structural Demands

该项目旨在提高我们对近源强地面运动和极端结构响应的理解，以开发改进的强地面运动强度矢量值测量方法，这些测量方法将更接近于对结构的潜在破坏。特别是，近源效应所带来的问题及其对非线性结构响应的影响将集中在这些效应可能导致比当前工程实践中与常用强度测量（如谱加速度）相关的更大的结构位移。该研究项目的一个主要内容是改进近源强地面运动的预测。它们的工程应用意味着，由于震源、地点和路径的影响，这些运动的范围和理解被理解和表示，特别是在近断层区域。这将有助于对非线性多自由度系统的动力响应及其在可能震源下的变异性进行最优预测。这种跨领域的地面运动和响应研究将在实际概率性能估计这一更大目标的背景下得到独特的协调。本项目是工程与地学研究相结合的项目，是国家自然科学基金（NSF） 98-36项目“美日城市地震减灾合作研究”的第二年资助项目

This project is aimed to improving our understanding of near-source strong ground motions and extreme structural response to develop improved vector-valued measures of strong ground motion intensity that will correspond more closely to the potential to damage structures. In particulalr, the problems posed by near source effects and their consequences for structural response in the nonlinear regime will be focussed on such effects may lead to substantially larger structural desplacements than current engineering practice associates with common measures of intensity, such as spectral acceleration.A major element of this research project will be improved prediction of near-source strong ground motions. Their engineering application implies that the range and undertainty in these motions due to source, site and path effects be understood and represented, particularly in the near-fault region. This will lead to optimal prediction of the dynamic response of nonlinear multi-degree-of-freedom systems, and its variabilty from likely earthquake sources. This cross-cutting ground motion and response research will be uniquely coordinated in the context of the larger objective of practical probabilistic performance estimation.This project involves integration of engineering and earth science investigation and is supported under the second year initiative "US-Japan Cooperative Research in Urban Earthquake Disaster Mitigation, " NSF 98-36