大降雨型滑坡临界雨量及潜势预报模型研究

Study of Critical Rainfall Amount and Potential Forecasting Model about Heavy Rainfall Regime Landslide

通过对湖北省1975～2002年发生的194次滑坡个例进行分析发现:滑坡时间主要发生在5～8月,占全年总次数的80%左右,与多年月平均雨量分布比较一致;滑坡区域主要位于湖北西部山地,高频中心在三峡库区;滑坡与前期降雨尤其是大降雨关系非常密切,大降雨型滑坡占滑坡总次数的63.1%.利用实效雨量计算方法,确定了大降雨型滑坡临界雨量,以此为依据建立了潜势预报模型.

By analyzing 194 landslide cases from 1975 to 2002 in Hubei Province,it is found that landslides in Hubei mainly occurred from May to August, which is similar to the monthly mean rainfall distribution;the main landslide area is the mountainous region in the western Hubei; and the high-frequency center is in the Three Gorges Reservoir area;landslides have a close relation with the antecedent rainfall amount, especially heavy rainfall, which accounts for 63.1% of the total amount. The critical rainfall amount was determined and the potential forecasting model of heavy rainfall regime landslides was built with the effective rainfall method.