北京地区泥石流灾害临界雨量阈值分析

Analysis of the critical rainfall thresholds for mudflow in Beijing,China.

对历史上北京市泥石流灾害发生时前3日的雨量、当日激发雨量和最大1小时雨量进行了分析,确定了临界雨量闽值。参照山洪灾害与降雨频率分析法,分3种方案对北京市的泥石流灾害与降雨频率进行分析,计算了各地区不同时段(最大10分钟、最大30分钟、最大60分钟、最大360分钟、最大24小时、最大3天及最大7天)的临界雨量;并利用历史上泥石流灾害发生时的雨量值对3种方案下的计算结果进行了验证和对比,最后确定了准确度较高的一种计算方案。

Mudflow is the main geological disaster in mountainous areas of Beijing, and rainfall is the main factor for causing mudflow. Based on the statistical data, the authors analyzed the rainfall three days before mudflow occurrence, mudflow-triggering rainfall on the event day and one-hour maximum rainfall and determined the critical rainfall thresholds. According to analyses of mountain torrents and rainfall frequencies, the authors used three schemes to analyze the mudflow disaster and rainfall frequencies in Beijing Municipality and calculated the critical rainfalls for mudflow in different time intervals （maximum 10 minutes, maximum 30 minutes, maximum 60 minutes, maximum 360 minutes, maximum 24 hours, maximum 3 days and maximum 7 days）. In addition, they checked and compared the results of calculations of the three schemes by using the rainfalls at the time of occurrence of historical mudflow disasters and finally determined one calculation scheme with a higher accuracy.