(1. Key Laboratory of Mountain Hazards and Surface Process，Chinese Academy of Sciences，Chengdu，Sichuan 610041，China；2. Institute of Mountain and Environment，Chinese Academy of Science and Ministry of Water Conservancy，Chengdu，Sichuan 610041，China；3. Department of Civil Engineering，University of Tokyo，Tokyo 113–8656，Japan)
Abstract：It has been observed that during an earthquake，the seismic response of slopes could be affected by the topography. Therefore，a general earthquake-induced slope model is defined and designed with five different slope shapes based on the statistical relations between the earthquake-induced landslides and the slope shapes. According to the test results，the amplification factor of the peak ground acceleration(PGA) on the surface of the slope was higher than that in the slope when the intensity of the input motion was relatively high. The site at the upper of the slope with the largest curvature on the middle of the slope surface(AC2) had the most notable amplification effect. The shape of the slope affected the natural frequency of the ground for the slope. The upper convex and lower concave slope had a natural frequency close to 5 Hz while the slopes of other shapes had a natural frequency close to 10 Hz. The critical acceleration values at failure ranged from 500 to 700 Gal，which were consistent with the calculated values for the slope from material strength tests. The shape of the slope affects the location and depth of its failure surface. The slope with large curvature radius(positive for convex and negative for concave) usually has a deeper sliding failure surface. The concave slopes have a shorter sliding distance and a smaller hazardous range. The convex and the upper convex and lower concave slopes have a longer sliding distance and a larger hazardous range. The linear and the upper concave and lower convex slopes have the longest sliding distance and the largest hazardous range. Therefore，the slopes with the linear or the upper concave and lower convex configurations have the highest risks，followed by the convex and the upper convex and lower concave slopes，while the concave slopes have a relatively strong ability to resist the ground motions and pose the lowest danger.
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2017, Vol. 36 
