Study On The Rock-soil Characteristics Of Slope Disintegration In South China

This paper took the serious erosion area in Changting country, Fujian Province as the research object. Based on field investigation wildly, 6 typical profiles of slope disintegration were chosen, being for field test and laboratory analysis, relationships between slope disintegration and rock-soil characteristics was discussed, and compress the rock-soil characteristics index of slope disintegration into several comprehensive factors by factor analysis.It's showed that, lots of joints and fractures exist in granite weathering mantle, include the decency joints and fractures, the tectonic cracks and release fractures; The forming and the scale of development of slope disintegration were controlled by the thickness of weathering mantle; There are 4 layers in typical profile of slope disintegration: the red soil layer, the sandy soil layer, the detritus layer and the crack weathered layer(also claimed the globular weathered layer); The main reason of disintegration is the microstructure destruction and the massive dry crevasses which made by dehydrates of soil body; Under the natural state and the air seasoning state, the intensity of disintegration is in order of the detritus layer>the sandy soil layer>the red soil layer; The content of organic matter are below 5.00g/kg mostly, in low level, and from strong to week ,it has a order ,the red soil layer, the sandy soil layer and the detritus layer; The texture in the order of the red soil layer>the sandy soil layer>the detritus gradually turn rough; The bulk density and the degree of compaction are the comprehensive reflection of rock-soil characteristics of slope disintegration. The total porosity has little difference in layers, the capillary porosity higher than non-capillary porosity, from the red soil layer to the detritus, the capillary porosity turn down and the non-capillary porosity turn up. The microaggregate mainly concentrate on two size which diameter in 0.25~0.05mm and 0.05~0.01mm.The content of >0.25mm aggregate is in low level, and in order of the red soil layer >the sandy soil layer>the detritus layer. While the layer deepening, the dispersion increase, the aggregation rate and the aggregation reduce obviously; The cohesive force of the red soil layer is bigger than the other layers, the equivalent friction angle also big relatively, so the...