多堆核电场址概率风险评价中的始发事件分析

绝大多数核电厂概率风险评价均以单个反应堆为单位，安全目标的制定也是如此。事实上，同一场址（site）上有多座核电厂（plant）、同一厂址（plant）上有多个反应堆（reactor）的情况并不罕见。为将概率风险评价从单个反应堆推广至整个场址，本文在定义场址风险的基础上，针对始发事件展开分析，给出其分类及识别方法建议。分析表明，多堆场址的始发事件可归入2类单堆始发事件，以及3类多堆始发事件。此结果是开展多堆场址概率风险评价的第1步，具有重要价值。

Initiating Event Analysis in Probabilistic Risk Assessmentfor Multi-unit Nuclear Power Site

As for most of the nuclear power plants worldwide,both the probabilistic risk assessments(PRA)and the safety goals are from a single reactor unit basis.In fact,the sites with multiple plants,as well as the plants housing multiple reactors,are definitely not rare.This study is aimed at bringing the PRA scope from the "single reactor" to the "whole site".With the site risk definition clarified,the initiating events(IEs)and proposed recommendations on classification and identification were analyzed in the paper.According to the results,the initiating events for the multi-unit sites can be categorized as two single-reactor IEs(SRIE)and three multi-reactor IEs(MRIE).This study is of great value as the first fundamental step to conduct the PRA for the multi-unit nuclear power sites.