ENGINEERING MEASURES AND THEIR EFFECT FOR MOBILIZATION OF DEBRIS FLOW FROM LANDSLIDES AT SHAOFANGGOU STREAM VALLEY

The function and effect of check dams and griile dams in certain catchments are studied extensively in China. However, there has been comparatively little research oncontrol measures and their effect to mobilization of debris-flow from landslides. A rainstorm induced debris flow hazard occurred on August 14, 2008 in Yingxiu Town of Sichuan Province, where was affected by the Wenchuan earthquake. The paper examines the motion process and the gully characteristics, landslides blocking point, the high depth of cutting, and their combinations. It is discovered that the whole basin comprehensive treatment shall prevent clogging and cutting. In order to control debris flow disaster happening again, check dams can weaken the leading kinetic energy in the upper reaches of the valley. Retaining plate and bed boards can control the landslide blocking point and protect the toecap in the middle reaches of the valley. Grillage damsand aqueduct can intercept the coarse particle and discharge debris flow smoothly. Then the paper compares the accumulated rainfall, solid matter involved in quantity, dynamic energy reserves and the gully characteristics around control measures. After discussing the initiation, the engineering measures for mobilization of debris-flow from landslides at Shaofang stream course has a good result. It provides a reference for engineering measures for debris-flow mobilization from landslides in the earthquake areas.