Seismic Canyon Interaction Effects in Earth and Rockfill Dams

[9320824] Bielak本项目研究土石坝的抗震性能，重点研究坝与支护之间的耦合效应，以及入射地震波空间变异性的影响。目前的设计方法通常假设一个刚性的大坝基础，然而在地震期间对土坝和石坝行为的观察表明，峡谷坝的相互作用可以显著影响它们的地震反应。本文的主要目的是阐明在何种条件下坝-峡谷相互作用效应具有实际意义，并发展可用于设计和修复实践的计算这些相互作用效应的方法。这些项目包括用二维和三维模型进行计算机模拟，以反映现实情况。由于主要的重点是清楚地了解大坝和峡谷之间的动力耦合影响大坝地震反应的机制，注意力主要局限于由干燥或致密饱和颗粒土和粘性土建造的大坝，这些土壤不易液化。然而，对于存在疏松饱和砂和无黏性粉砂的情况，也考虑了地震液化的评价。＊＊＊

9320824 Bielak This project investigates the seismic performance of earth and rock-fill dams, focusing on the coupling effects between the dam and its support, as well as on the effects of the spatial variability of the incoming seismic waves. Current design methods generally assume a rigid dam foundation, whereas observations of the behavior of earth and rock-fill dams during earthquakes suggest that canyon-dam interaction can significantly influence their seismic response. The main objective is to elucidate the conditions under which dam- canyon interaction effects are practically significant, and to develop methods that can be used in design and remediation practice for calculating these interaction effects. The projects involves computer simulations with two- and three-dimensional models which reflect realistic conditions. In as much as the main focus is on gaining a clear understanding of the mechanism by which the dynamic coupling between the dam and the canyon affects the seismic response of the dam, attention is confined largely to dams constructed of either dry or dense saturated granular soils and cohesive soils that are not susceptible to liquefaction. Some consideration, however, is given to seismic liquefaction evaluation for cases in which loose saturated sands and cohesionless silts are present. ***