Identification and Modeling of Earthdam Response During Northridge, January 17, 1994 and Previous Earthquakes

9416248 Elgamal地震加速历史被记录在1994年北岭地震震中50英里半径内的8个测量良好的土坝上。在1971年的圣费尔南多地震和1987年的惠蒂尔地震中，这些大坝也遭受了强烈的地面震动。目前有大量有价值的输入数据和响应加速历史数据（Northridge、Whittier和San Fernando地震）可用于校准和验证简化和复杂的计算分析程序。过去对圣费尔南多和惠蒂尔记录的加速度的分析大大有助于我们对土坝地震反应机制的理解；只有通过分析实际的全面地震反应才能做出贡献。最近恢复的北岭加速历史提供了一个独特的机会，可以在早期对Santa Felicia， pudingstone， Cogswell和Brea水坝进行的深入研究结果的基础上进行研究。该项目的目标是：(i)利用先前从圣费尔南多和/或惠蒂尔地震中确定的动力特性，对每个大坝进行预测性（a /B级）计算分析；（ii）根据新获得的北岭数据集（不同的震动幅度和频率内容），严格评估先前确定的土坝特征；（iii）定义简化的分析/设计程序，并明确识别任何相关的限制和/或优势；（iv）以数据库形式记录已确定的属性，其中包括北加州（列克星敦、安德森和长谷水坝）、南加州（圣费利西亚、普丁斯通和布雷亚水坝）和墨西哥（拉维利塔和埃尔因菲尔尼洛水坝）的大量现代土/堆石坝。＊＊＊

9416248 Elgamal Earthquake acceleration histories were recorded on and around eight well instrumented earth dams within a 50 mile radius of the 1994 Northridge earthquake epicenter. These dams were also subjected to strong ground shaking during the 1971 San Fernando, and the 1987 Whittier earthquakes. A large data set of valuable input and response acceleration histories is currently available (Northridge, Whittier, and San Fernando earthquakes) for calibration and verification of simplified as well as elaborate computational analysis procedures. Past analyses of the San Fernando and Whittier recorded accelerations have significantly contributed to our understanding of earth dam seismic response mechanisms; contributions which were possible only through analyses of actual full-scale seismic response. The recently recovered Northridge acceleration histories offer a unique opportunity to build on the results of thorough studies conducted earlier for the Santa Felicia, Puddingstone, Cogswell and Brea dams. The objective of this project is to: (i) conduct a predictive (Class A/B) computational analysis for each dam using the dynamic properties identified earlier from the San Fernando and/or Whittier earthquakes, (ii) critically assess the previously identified earth dam characteristics in view of the newly acquired Northridge data set (of different shaking amplitudes and frequency contents), (iii) define simplified analysis/design procedures, and clearly identify any associated limitations and/or strengths, and (iv) document the identified properties in a database form that includes a large number of modern earth/rockfill dams in Northern California (Lexington, Anderson and Long Valley dams), Southern California (Santa Felicia, Puddingstone, and Brea dams), and Mexico (La Vilita and El Infiernillo dams). ***