密松水电站面板堆石坝抗震设计与安全性评价

Anti-seismic design of CFRD of Myitsone Hydropower Station and its safety evaluation

密松水电站面板堆石坝属于超宽河谷的面板堆石坝,其抗震分析还缺少相应的工程经验。针对面板堆石坝在强震中易产生坝体永久变形过大及面板易破损等问题,采用拟静力法和有限元时程动力法,分析了堆石坝的加速度和应力反应、面板应力、接缝变形、坝体地震残余变形以及坝坡的动力稳定性,对大坝的抗震安全性进行了综合评价。结果表明,在设计与校核地震作用下,坝坡稳定性满足规范要求,坝体永久变形与同类工程相当,面板应力状态满足抗震安全要求,面板接缝变形在止水结构允许范围之内。

The concrete faced rockfill dam （CFRD） of Myitsone Hydropower Station is built in an extra -wide valley, and lit- tle seismic engineering experience is available in the anti - seismic design. In view of the problems such as large permanent de- formation in the CFRD and face slab breakage in a strong earthquake, quasi - static method and FEM time - history method are applied to analyze the dynamic response of acceleration and stress of roekfill dam, face slab stress, joint deformation, and residu- al deformation of dam body and dynamic stability of dam slope. And the anti - seismic safety of dam is evaluated. The results show that in the ease of design and check earthquake, the dam slope stability meets the requirements of specification; the dam permanent deformation is at an equivalent level comparing with other similar projects; the face slab stress status meets the seismic safety requirements; the joint deformation of face slab is within the permissible range of sealing structure.