汶川8.0级地震后，震区在强降雨作用下不仅诱发形成大量的一般暴雨型泥石流灾害，还诱发形成危害性更大的溃决型泥石流。通过泥石流勘查应急报告和野外实地调查，核实选取了汶川震区9条溃决型泥石流沟和34条一般型泥石流沟冲出量的相关参数作为样本数据，先对汶川震区溃决型泥石流的特征进行分析总结，其次对比分析汶川震区溃决型泥石流与一般型泥石流冲出量的特点及其是否堵江的原因，结果表明溃决型泥石流冲出量较一般型泥石流要大出几十倍，且比一般型泥石流更易造成堵江。最后建立一般型泥石流冲出量多因子统计预测模型，提高了一般型泥石流冲出量普遍预测模型的精度，验证显示该预测模型对汶川震区一般型泥石流冲出量的预测具有科学有效性。研究结果为进一步深入研究震区溃决型泥石流提供理论依据，也为震后灾区一般型泥石流的减灾防灾工程设计提供计算方法。%A large number of general debris flows were triggered by rainstorm in the seismic area after Wen-chuan earthquake.Meanwhile,bam-break debris flows were triggered by rainstorm.Therefore,we select the inves-tigation data from the report of emergency exploration for debris flow in the seismic area and field investigation which conduct 34 common debris flow gullies and 9 break debris flow gullies.Firstly,we analyze and summarize the characteristics of break debris flow in Wenchuan earthquake area.Secondly,break debris flow is easier to block the river than general debris flow,because the run-out amount of break debris flow is several times larger than the common debris flow.Finally,applying the multivariate regression analysis,a multiple-factor and regression-statisti-cal model which has been improved the accuracy ofthe runout volume is established to estimate the run-out volume of the common debris flow.The validation shows that the new model is suitable for predicting the run-out volume of the common debris flow in Wenchuan earthquake areas.The results of the study not only provides more effective and scientific equations to design disaster prevent and mitigation engineering for the common debris flow,but pro-vides the basis theory of researching further depth for dam-break debris flow in the seismic area.
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