【摘要】 为研究震后环境突变条件下的泥石流形成模式和机理,开展震后泥石流防治和预测,根据震后泥石流形成环境特点,设计泥石流起动装置,开展震后泥石流形成模式和机理试验。本研究共进行了25组试验,主要研究了泥石流在不同坡度情况下的泥石流形成模式和机理,结果表明:1)在坡度8°～12.5°情况下,泥石流的形成模式是冲蚀→冲沟→崩塌→堵塞→溃决→泥石流的模式;2)在坡度12.5°～17.5°情况下,泥石流的形成模式是逐渐侵蚀加剧(朔源侵蚀、下切侵蚀和侧蚀),容重逐渐增加形成泥石流的模式;3)在坡度17.5°～25°情况下,泥石流的形成模式是坡面流水→入渗→失稳→下滑→流态化的模式;4)根据孔隙水压力变化特征,不同的起动模式下的土体内部孔隙水压力变化特征不同,孔隙水压力的变化可以解释不同泥石流起动模式的机理特征。根据研究结果,可以对不同起动下的泥石流模式进行不同的防治规划,同时结合泥石流起动过程中孔隙水压力的变化,可以解释泥石流起动的模式,对开展震后泥石流预报提供了参考。更多还原

【Abstract】 In order to understand the initiation model and mechanism of debris flow,and forecast and prevent it after earthquake,the facilities of debris flow initiation were designed according to the post-earthquake environment to study the debris flow initiation mechanism.The tests of 25 groups were carried out at different slopes using the same soil material to study the debris flow initiation at varies slopes.The results showed that the initiation mode of debris flow was erosion → gully → collapse → block → failure and transformed into debris flow between 8° ~ 12.5° as initiation due to dam-failure.The initiation mode of debris flow was increased erosion gradually(down cut erosion,back word cut and lateral erosion) with the bulk density increasing and transformed into debris flow between 12.5° ~ 17.5° as initiation due to erosion.The initiation mode of debris flow was surface flow → infiltration → failure → fluidization and transformed into debris flow between 17.5° ~ 25° as initiation due to slope failure.The change character of water pore-pressure was different at different slope experiments,and the water pore-pressure inner soil revealed the initiation mechanism of debris flow at different slope.更多还原