The derived mechanism and deformation characteristics of slip surface of loess- weathered rock contact surface slope
WANG Ping1，2，3，WANG Huijuan2，CHAI Shaofeng2，3，FENG Wei4，WANG Jun2，3，XU Shuya2
(1. Institute of Geotechnical Engineering，Xian University of Technology，Xian，Shaanxi 710048，China；2. Lanzhou Institute of Seismology，China Earthquake Administration，Lanzhou，Gansu 730000，China；3. Key Laboratory of Loess Earthquake Engineering，Gansu Province and China Earthquake Administration，Lanzhou，Gansu 730000，China；4. Xian Geological Survey Center，China Geological Survey，Xian，Shaanxi 710048，China)
Based on the shaking table model test，the characteristics of deformation and failure of the slope under different ground motion intensity are studied in the loess-weathered rock contact surface slopes in Haitou Village，Tianshui，Gansu Province. Furthermore，the development of vertical cracks during the period of crack generation，surface peeling and slop slide were analyzed. Combined with the results of soil strain test，the mechanism of the slope instability and the derivation of the slip surface are revealed. The results show that the influence of vertical loading on the model is less than that of horizontal under the same seismic intensity. The vertical direction of soil is easily to induce vertical crack while the horizontal is more intend to induce transverse crack. Moreover，vertical crack is the main cause of surface friability，but transverse crack is the main driving force of slope instability. At the top of the slope，the composite failure of tension and shear occurs under the action of seismic load，which leads to the downward transition of the transverse surface of the slope to the contact surface of the loess-weathered rock，forming the slip surface of the slope failure.
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2018, Vol. 37 
