摘要
The Daguangbao landslide in Anxian County is the largest landslide occurred in the Wenchuan earthquake.In order to examine the formation mechanism of the landslide,based on field investigation,a 3-dimensional vibrostand physical simulation test is used to study the formation mechanism and destroy process and the affinity of the landslide and the slope structures is discussed.The results indicate that the landslide is a wedge and trough shaped fall,it formed by the underlying layer of sinianperiod dolomitite and early X tectonic fractures orthogonal to the layer.The landslide formed by the layer and crevice in the earthquake.Tension crevice appeared first on top of the slope,soon after shearing crack appeared on the bottom of the slope,the crevice formed in order.The pull cracks on top of the slope under vibrations,the slope slide face forms by the layer on the right of the slope,and tension crevice appear on the left of the slope.They form a wedge and trough shaped fall.The slope is a fallback one and it fell back repeatedly.