Energy identification method for dynamic failure mode of bedding rock slope with soft strata
FAN Gang1, 2, ZHANG Jian-jing1, 2, FU Xiao1, 2, WANG Zhi-jia1, 2, TIAN Hua3
1. School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031, China; 2. Southwest Jiaotong University, Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, Chengdu 610031, China; 3. Southwest Geotechnical & Design Institute of China Nuclear Industry, Chengdu 610061, China
Abstract:Based on the Hilbert-Huang transformation and marginal spectrum theory, large scale shaking table tests on rock slope with soft strata are performed. The energy method for dynamic failure mode identification of bedding rock slope with soft strata is studied according to the test results. The research results in this work show that the peak value and characteristic frequency of marginal spectrum can represent the dynamic damage development process in the rock slope clearly. In the bedding rock slope with soft strata, the dynamic damage first occurs on the slope shoulder, and then the damage location moves to the lower elevation with the increase of input seismic wave amplitude, and finally, the slope is sheared out at the location of upper soft strata. In the displacement monitoring, the displacement on the slope shoulder has fast change and then that at the upper location has quick change, that is to say, the displacement monitoring results are in agreement with the results of the marginal spectrum analysis. The dynamic damage degree near the slope face is more severe than that in the inner part of slope. The characteristic frequency in the lower-middle part is of great difference, indicating that the lower-middle part is a discontinuous zone of dynamic response for bedding rock slope with soft strata. The dynamic failure of bedding rock slope mainly includes vertical rip in the trailing edge of slope and the shearing out at the upper soft strata, that is, the dynamic failure mode of bedding slope with soft strata is a rip-slippage-avalanche mode. The proposed method will be a guide for identification of slope dynamic failure mode.
范刚, 张建经, 付晓, 王志佳, 田华. 含软弱夹层顺层岩质边坡动力破坏模式的能量判识方法研究[J]. 岩土工程学报, 2016, 38(5): 959-966.
FAN Gang, ZHANG Jian-jing, FU Xiao, WANG Zhi-jia, TIAN Hua. Energy identification method for dynamic failure mode of bedding rock slope with soft strata. Chinese J. Geot. Eng., 2016, 38(5): 959-966.
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