基于实际震害的土石坝永久变形估算

土石坝地震震害主要表现为震后永久变形,利用永久变形来评价大坝的抗震稳定与安全更为合理可行。本文结合30余座土石坝的震害资料,研究了土石坝的自振周期等基本自振特性,同时对场地地震卓越周期、滑块屈服加速度与大坝最大加速度反应等主要影响因素进行了深入分析,提出了基于土石坝实际震害的永久变形计算公式,并与Makdisi、Sarma等方法的计算值进行比较,该方法具有较好的计算精度。

Estimation of earthquake-induced permanent deformation for earth dam based on seismic damage

Earthquake-induced permanent deformation is the main performance of rockfill dams and embankments subjected to earthquake shaking,which is more reasonable than a factor of safety in evaluating seismic stability and safety of dams. In this paper,according to seismic damage of more than 30 earth dams, an in-depth study is anducted on natural vibration characteristics such as natural period are studied, factors affecting earthquake displacement such as predominant period,yield acceleration of sliding mass,maximum crest acceleration,and then calculation formulas are given to evaluate the permanent deformation. Compared with values of Makdisi''s,and Sarma''s method,this method is relatively precise.