Abstract Landslides on low-angle slopes can be caused under the coupled effect of rainfall and earthquake. In order to investigate the influence of duration of time between rainfall and earthquake on the scale and failure mode of landslides, a low-angle loess slope at Lanzhou New Area was adopted as a prototype, and a large-scale shaking table test was performed. By using self-designed artificial rainfall equipment, 30 mm of rainfall 12 h before shaking and 20 mm rainfall immediately before shaking were exerted on the slope model to investigate the responses and determine the differences in the failure mode of the low-angle slope under different rainfall cases. To measure the dynamic response of the test model at each working condition, 18 acceleration sensors, 7 soil-pressure sensors, 10 pore water-pressure sensors, and optical measurement techniques were used. The results show that the acceleration amplification effect increased with increasing intensity and the soil pressure increased with decreasing elevation under the long-term effects of rainfall before earthquake, but the value on the slope surface decreased under the short-term effects of rainfall before earthquake. The dynamic pore pressure value varied considerably between positive and negative and the maximum displacements at slope surface increased about 69.7% under the short-term effects of rainfall before earthquake. Large displacements and deep cracks occurred on the surface of the slope, mainly caused by the loess losing its strength and the large inertial force on the surface owing to the long-term effect of rainfall before the earthquake. The damage to the low-angle slope was mainly caused by liquefaction and the loss of loess strength under the influence of short-term rainfall before the earthquake. The failure of the slope was soil flow, which was similar to the sliding process of the Yongguang village landslides. Finally, we note that the effect of coupled effect on the low-angle slope should be evaluated in future work from two aspects: the intensity of rainfall and earthquake and the time when rainfall occurred before the earthquake.

中文翻译：

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震前长短期降雨影响下低倾角黄土边坡动力特性试验研究

摘要 在降雨和地震的耦合作用下，低倾角斜坡容易发生滑坡。为研究降雨和地震间隔时间对滑坡规模和破坏模式的影响，以兰州新区低倾角黄土边坡为原型，进行了大型振动台试验。利用自行设计的人工降雨设备，对边坡模型施加摇前12 h降雨30 mm和摇前即刻降雨20 mm，研究低角度边坡在不同条件下的响应，确定其破坏模式的差异。降雨情况。测量试验模型在各工况下的动态响应，加速度传感器18个，土压力传感器7个，孔隙水压力传感器10个，并使用了光学测量技术。结果表明，在震前降雨的长期作用下，加速度放大效应随着强度的增加而增大，土压力随着海拔的降低而增大，而在震前降雨的短期作用下，坡面值减小。动孔隙压力值正负变化较大，在震前降雨的短期影响下，坡面最大位移增加了约69.7%。边坡表面出现大位移和较深裂缝，主要是由于地震前长期降雨的影响，黄土失去强度，地表惯性力较大。低倾角边坡的破坏主要是由于震前短时间降雨的影响，造成黄土液化和强度损失。斜坡的破坏是土流，类似于永光村滑坡的滑动过程。最后，我们注意到耦合效应对低倾角边坡的影响在未来的工作中应从降雨和地震的强度和地震前降雨发生的时间两个方面来评估。