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| Geotechnical centrifugal model test on sandy soil slope stability |
| LUO Qiang1，2，ZHU Jiangjiang1，2，ZHANG Ruiguo1，2，JIANG Liangwei1，2，ZHANG Zheng1，2 |
| (1. School of Civil Engineering，Southwest Jiaotong University，Chengdu，Sichuan 610031，China；2. MOE Key Laboratory of High-speed Railway Engineering，Southwest Jiaotong University，Chengdu，Sichuan 610031，China) |
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Abstract The effects of slope gradient and soil moisture content on the stability of sandy soil slopes were investigated with the geotechnical centrifugal model test，the deformation characteristics and failure modes of sandy soil slopes under centrifugal load were analyzed and the mechanism of water migration influencing the slope stability was discussed. Meanwhile，the test results together and the data from other laboratories in the parallel tests of geotechnical centrifugal modeling that were performed in 2013 were analyzed on the characteristics of error probability of centrifugal model test on sandy soil slopes. It is shown that the deformation of the sandy soil slope presents obvious brittle failure characteristics，and the failure mode features the shallow slippery with a straight linear failure plane. There is a close relationship between the centrifugal acceleration at failure and the slope gradient under the condition of weak water migration. The water migration that exists in sand with high moisture content leads to the remarkable variation of the sand strength，which is the essential factor affecting the stability of the sandy soil slope. The statistical data of centrifugal acceleration at failure present the feature of normal distribution. Notable systematic error is observed in the test process，though the test error is mainly the random one.
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2018, Vol. 37 
