我国核电站选址的区域稳定性研究

核能是重要的能源之一。利用核能发电在世界能源构成中占有愈来愈重要的地位。 修建核电站,要求严格的安全和环境条件,必须绝对保证核电站在各种可能遭遇的自然和人为事件情况下,均不致发生造成放射性物质外泄的事故。因此,除了要求核电站建筑物和各种装置本身安全可靠并拥有周密而充分的安全措施外,特别要求在选择厂址时,必须充分查明和预测各种可能遭受的自然灾害。在各种能危及核电站安全的自然灾害中,与工程地质直接有关的问题有许多方面,本文仅就核电站选址中,厂址地区的区域稳定问题作一简要探讨。

REGIONAL STABILITY RESEARCH TO NUCLEAR POWER PLANT SITING IN CHINA

China is a high-seismic country.Eegional stability research is one of very important topics for evaluating geological conditions at a nuclear power plant site.According to the concrete cases in China,this paper gives an analysis of the investigations and evaluation of both the surface faulting and ground motion caused by earthquakes.The surface faulting has two categories in nature.One belongs to slow creeping,and the other to sudden breaking.The former is quite uncommon and only happens in the seismically active areas in China.Hence,it may be left ?out of consideration.The latter i.e.a seismic fault caused by a strong earthquake is a general phenomenon in China.The historical earthquake records show that such breaking could be produced only by a earthquake of M_s>6.Accordingly the authors propose following criteria to identify the capable faults.1)Faults,offsetting the Quarternary deposits since Middle Pleitocene(Q2).2)Faults,where the earthquakes of the magnitude large than 6 have occurred or will occur.3)Faults,which have tectonical relation with the abovementioned 1)and/or 2)capable faults,such as a branching fault,a cross-intersecting subfault.China is the only one country having records of the earthquakes in earlier history.The intensity zoning on the basis of these abundant records of historical earthquakes together with the regional seismic-geoloieal conditions and seismic activities is available in China.Therefore,the authors believe that the Operation Basis Earthquake(OBE)of a nuclear power plant would be determined by this local site basis intensity and the Safe Shutdown Earthquake(SSE)of it would be appraised according to those principles and methods delineating the future earthquake risk areas and predicting their maximal,magnitude,with the assumption that the hypocenter will occur in a potential seismic structure at the nearest portion from the site.