Development of spatial correlation and coherency model for simulating tri-directional ground motion fields at the dam-foundation interface

占地面积大的结构和基础设施，包括水坝，受到空间变化的影响， 多分量地震动多点或多点三向地震动 对于给定的空间相干性和三分量， 在给定概率水平下指定的反应谱（即，地震危险）。然而，空间信息 三向地面运动的相干性是不可用的。此外，地震危险性建模是敏感的 地震动残差的标准差和（事件内）空间相关性 预测方程（GMPEs），通常是根据来自广泛网络的记录估计的， 记录站之间的最小距离大于约一千米的站。的 如果最小值 基础设施的支撑之间的距离与记录的距离相似。然而，一个必须 调查什么是最合适的GMPE，如果兴趣集中在估计地震危险性， 局部区域（如坝基）内的多个支座。 本建议旨在评估地震运动措施和地震危险的概率模型， 适用于局部区域，并通过考虑开发经验空间相干性模型 多方向的地面运动为了分析，从密集台阵的地震动记录与短 将采用站到站距离。地震动测量的概率模型 并以空间相干模型为基础，模拟了多个方向的三向地震动 局部区域内或坝基界面处的支撑。该项目开发的算法是 有助于评估大坝的地震风险，并可作为HATCH基于风险的工具的一部分， 评估大坝安全性，并确定长期安全维护计划的优先次序。 NSERC为该项目提供的资金将用于支持一名博士后研究员六个月。

Structures and infrastructure with large footprints, including dams, are affected by spatially varying multi-component ground motions. The tri-directional ground motions at multiple supports or the ground motion fields at the dam-foundation interface can be simulated for given spatial coherency and tri-component response spectra specified at given probability level (i.e., seismic hazard). However, information on spatial coherency for tri-directional ground motions is unavailable. Moreover, the seismic hazard modeling is sensitive to the standard deviation and the (intra-event) spatial correlation of the residuals of the ground motion prediction equations (GMPEs), which are usually estimated based on records from a broad network of recording stations with a minimum distance between the stations more than about one kilometer. The application of the GMPEs together with their residuals derived using such records is adequate if the minimum distance between the supports of the infrastructure is similar to those of the records. However, one must investigate what are the most appropriate GMPEs, if the interest is focused on estimating the seismic hazards at multiple supports within a localized area, such as dam base. This proposal is to assess the probabilistic model of ground motion measures and seismic hazard that are applicable to a localized area, and to develop empirical spatial coherency model by considering multi-directional ground motions. For the analysis, the ground motion records from the dense arrays with short station-to-station distance will be employed. The developed probabilistic models of ground motion measures and the spatial coherency models are used as the basis for simulating tri-directional ground motions at multiple supports within a localized area or at the dam-foundation interface. The algorithm developed in this project is useful to assess seismic risk of dams, and could be integrated as part of HATCH's risk-based tools for evaluating dam safety and for prioritizing long-term safety maintenance program. The funding from NSERC for this project is to be used to support a post-doctoral fellow for six months.