日本盖马哈雷溪泥石流发生在旱季（１９９６年１２月６日），这个季节通常是很少发生泥石流的。通过从直升飞机上观察（由于大雪无法进入泥石流物质来源区）和分析航空照片，并采用不排水扭矩控制式高速环剪切试验仪模拟洪积物的不排水加载试验，认为引发这次泥石流的可能机制是，初始滑坡落在洪积物上，导致洪积物液化，从而发生泥石流。在传统概念中，液化作用仅在非常松散和充分饱水的沙中发生。然而，只要剪切带中的颗粒在剪切期间被压碎并在剪切带中发生负剪胀作用，滑面液化作用甚至可发生在密实状态下。 The mud-rock flow in the Gaihamaki Creek in Japan occurred during the dry season (December 6, 1996), and debris flow is usually rare in this season. Through the observation from the helicopter (due to heavy snow can not enter the debris source area) and analysis of aerial photographs, and using undrained torque-controlled high-speed ring shear testers to simulate the non-drainage load test of the sediment, that caused this debris flow The possible mechanism is that the initial landslide landed on the alluvial material, resulting in the liquefaction of the alluvial material, resulting in debris flow. In the traditional concept, liquefaction occurs only in very loose and well-saturated sand. However, as long as the particles in the shear band are crushed during shearing and negative dilatancy occurs in the shear band, slip surface liquefaction can occur even in tight conditions.