从汶川地震特点谈水电站选址中地震地质灾害问题

Consideration on the Geological Hazards in Hydropower Station Site Selection from the Experiences of Wenchuan Earthquake

合理选址是提高大中型水电工程抗震能力的重要基础,在选址和枢纽布置过程中,应坚持"先避让,后处理,再防护"的原则,主要建筑物不宜建在已知的活动断层上,并应尽量远离活动断裂带。高烈度山区的地震地质灾害威胁水电工程的安全,坝址选择时应尽量避开地形陡峻、风化卸荷强烈地段。选定坝址后,应坚持适当扩大工程区地震地质灾害的调查、评价及工程处理范围,尽可能地处理可能影响工程安全的边坡。对工程处理范围以外的自然近坡,也要采取一些被动、主动或二者相结合的防护措施,最大程度地减少地震灾害对工程建筑物的影响。

Reasonable site is an important basis to improve the seismic capacity of large and medium hydropower projects. In the process of site selection and project layout, the principle of ＂first avoidance, post-treatment and then protective＂ should be respected, the main building should not be built on the known active fault and should try to stay away from active faults. In mountain areas with high-intensity earthquake, dam site selection should try to avoid the area with steep topography, strong weathering and unloading rock. After selecting, it should insist on appropriate expansion of the project area survey and evaluation of seismic geological disasters, the slope that may affect the safety of project should be dealing with as possible. For natural slope outside the scope of project treatment, some passive, active or a combination of both protective measures should also be taken to minimize the seismic hazards.