【摘要】 对汶川地震灾区2008-2010年的暴雨泥石流以及我国台湾集集地震后2001、2004、2009台风引发的泥石流雨量过程进行了分析。结果表明,34.4 mm是震后短时间内泥石流暴发的特征雨量;临界降雨强度/持续时间的关系式表明:在相同的降雨过程下,汶川地震灾区的泥石流比集集地震灾区的泥石流要容易暴发。通过泥石流暴发时段与峰值降雨时段的时间先后关系以及与前期雨量关系的研究,将强震后泥石流分为前期雨量控制型和短历时降雨控制型。其差异主要体现在超强短历时雨强直接触发和充足的前期雨量条件下,接近或达到34.4 mm/h的雨强触发。造成不同的泥石流控制类型的原因在于两地震对泥石流影响程度差异以及激发的雨量过程特征不同。更多还原

【Abstract】 This paper proposed a study on the rainfall of debris flows between 2000 and 2010 in Wenchuan earthquake zone,and debris flows triggered by typhoon of 2001,2004,and 2009 in Chichi earthquake zone.The analysis reveals that a rainfall intensity of 34.4 mm/h is the characteristic threshold of debris flows after a short time of strong earthquake.Both of the two relationships between mean rainfall intensity and duration in Wenchuan and Chichi earthquake zone tell us that the debris flows in Wenchuan earthquake zone can be triggered more easily when suffered a same storm.The selected debris flows after strong earthquake can be classified into pre-storm control pattern and short-duration rainfall control pattern by the relationship of the chronological order between debris flow occurrence and time of peak rainfall during a rainstorm,as well as the triggering rainfall when debris flow occurred.The short-duration rainfall control pattern refers to that debris flows were triggered by rainfall intensity far beyond 34.4 mm/h,and debris flow occurrence coincides with the peak rainfall interval.The pre-storm control pattern debris flows refers to that debris flows were triggered by a rainfall intensity close to 34.4 mm/h while cannot been triggered without insufficient rainfall even there is a larger rainfall intensity than 34.4 mm/h before the triggering rainfall interval.Finally,the reasons why these debris flows were triggered differently may attribute to the properties of strong earthquake,such as the magnitude,ground shaking duration,and influence on volume of loose materials as well as the different rainstorm.更多还原