【摘要】 映秀湾水电站是汶川"5.12"大地震距离震中最近的水电工程,该电站已投产多年,震时受到严重影响,地震影响烈度高达XI度。首先,根据震后现场考察,分析地下厂房受到的震害影响。调查表明,震后的映秀湾地下厂房围岩总体稳定,但主厂房内出现了局部震损现象,造成吊车无法正常运行;母线洞和交通洞与主厂房的交口处有外漆脱落、围岩轻微开裂现象。然后,根据距离震中最近的强震测站卧龙台在主震时监测到的数据,运用通用软件FLAC3D,对映秀湾地下厂房进行了动力响应分析。计算结果表明,地下厂房上、下游边墙在极短时间内发生的横向变形变幅分别达到5.4和3.0cm,边墙部位围岩拉应力超过围岩抗拉强度,出现拉裂。动力响应分析结果与现场震损考察所反映的基本规律相符,可以从数值分析的角度大致解释在震害调查中所发现的震损现象,为水电工程震后修复加固和相关科研提供参考。更多还原

【Abstract】 Yingxiuwan hydropower station is the nearest hydropower project to the epicenter of Wenchuan"5.12" earthquake. This hydropower station has been put into operation for several decades. It was severely affected by the earthquake,and its earthquake response intensity amounted to 11 degrees. Firstly,according to the in-situ investigation after the earthquake,the earthquake damage of underground powerhouse is analyzed. The following results are obtained:(1) The general stability of Yingxiuwan underground powerhouse is favorable. However,a certain local deformation is observed at the sidewall area of the main powerhouse,which lead to local failure in the main powerhouse causing crane to be unable to operate. (2) The paint on the bus bar opening sheds off and the surrounding rock in the traffic opening slightly cracks. Then,according to the data of Wenchuan earthquake monitored by Wolong strong motion station,which is the nearest station to the epicenter,the dynamic response analysis was conducted by FLAC3D. The calculation results show that the transverse deformation increments of the upstream and downstream sidewalls are 5.4 and 1.0 cm,respectively,in a short time;and the tensile stress at sidewall area exceeds surrounding rock′s tensile strength,which causes tensile crack. Comparison of the monitoring data and calculating results show that the dynamic response analysis results agree with the regularity derived from the in-situ earthquake damage investigations. Therefore,the investigated earthquake damage can be explained through numerical analysis;and it provides references to the postseismic reinforcement and rebuilt work of hydropower projects as well as relative researches.更多还原