STUDY OF MECHANISM OF LANDSLIDE INDUCED BY RAINFALL IN GENTLY INCLINED RED STRATUM IN EAST SICHUAN BASIN
ZHANG Ming1，HU Ruilin2，YIN Yueping3，WU Ruian1
(1. Faculty of Engineering，China University of Geosciences，Wuhan，Hubei 430074，China；2. Institute of Geology and Geophysics，Chinese Academy of Sciences，Beijing 100029，China；3. China Institute of Geo-environment Monitoring，Beijing 100081，China)
Abstract：Gently inclined red stratum widely distributes in East Sichuan Basin. Dip angle of this type of stratum is always between 3° and 10°，which is far less than the friction angle between bedding planes. In theory，the bedding landslide is unlikely to occur in red stratum. But in fact，rainfall induced landslide in gently inclined red stratum occurs frequently，which leads to a huge threat to the local people. Taking Qingning landslide in Da County，Sichuan province as an example，the geological model through field investigation and exploration is built；then analyzes the seepage field and static water pressure distribution before the landslide；a slope stability was analyzed based on the results of above seepage analysis. In order to obtain the characteristics of pore water pressure and shear resistance，the sliding zone soil is sampled to conduct ring shear test. The results indicate that landslide is due to coupled action of water pressure and shear resistance decreasing of sliding zone soil. The horizontal pushing force and vertical uplifting force due to rainfall infiltration initiated the landslide to deform and slid slowly，and then shear resistance decreasing of sliding zone soil led to the rapid sliding. Furthermore，a long rainfall and then a strong rainfall are deemed to be the necessary condition of landslide. Conclusions of this paper are the new findings in this field and can supply theoretical support for landslide forecasting and prevention in East Sichuan Basin.
张 明1，胡瑞林2，殷跃平3，吴瑞安1. 川东缓倾红层中降雨诱发型滑坡机制研究[J]. 岩石力学与工程学报, 2014, 33(S2): 3783-3790.
ZHANG Ming1，HU Ruilin2，YIN Yueping3，WU Ruian1. STUDY OF MECHANISM OF LANDSLIDE INDUCED BY RAINFALL IN GENTLY INCLINED RED STRATUM IN EAST SICHUAN BASIN. , 2014, 33(S2): 3783-3790.
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2014, Vol. 33 
