汶川地震对硗碛大坝影响分析

硗碛大坝为砾石土心墙堆石坝,最大坝高125.5 m,坝基覆盖层深70 m.其坝址距5.12汶川地震震中71km,地震发生时坝区有强烈震感.该坝埋设有较完整的大坝安全监测仪器,通过对大坝变形、渗流渗压及应力应变监测资料的分析,考察汶川地震对硗碛大坝工作性态产生的影响.分析结果表明,整个大坝在遭遇M8.0级大地震之后,外观无异常现象,总体运行性态基本稳定.但此次地震对大坝各个部位的变形、渗流渗压和应力应变仍有一定影响,特别是左岸防渗帷幕受到局部损坏.

Analysis of effect of Wenchuan earthquake on Qiaoqi Dam

The Qiaoqi Dam on the Baoxing River is a rockfill dam with gravelly soil core.The maximum dam height is 125.5 m;and the overburden thickness as the dam foundation is about 70 m.The dam site was shocked intensely during 5.12 Wenchuan Earthquake at an epicentral distance of about 71 km.The dam is well instrumented to monitor its working sate.Through the comparative analysis of the pre-earthquake and post-earthquake monitoring data of the deformation,stress and strain,seepage flow and seepage pressure of the dam,the impact of the Wenchuan Earthquake on Qiaoqi Dam is obtained.The results show that the dam remains a normal working state after the great earthquake.However,certain effects were displayed on the dam's deformation,seepage and stress and strain.Especially,some parts of the grouting curtain in the left abutment were damaged by the earthquake.