A predictive model on equivalent number of strain cycles for earthquake loads
GAO Guang-yun, SHI Chao, CHEN Qing-sheng
1. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji University, Shanghai 200092, China; 2. Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
Abstract：The equivalent number of strain cycles plays an important role in seismic response analyses. The existing calculation methods for the equivalent number of strain cycles are mostly based on accumulated damage theories. However, the time history of an earthquake load is required in the prediction using these methods, which is complicated in the equivalent conversion. In order to address these issues, 296 records of horizontal seismic time-history records, which cover different kinds of the epicenter distance and magnitude, are used in this study. The equivalent number of strain cycles is calculated for the sand with a relative density of 45% subjected to the selected earthquake load. Based on the statistical analysis using the nonlinear mixed-effects model, a predictive model for the equivalent number of strain cycles is proposed for both unidirectional and bi-directional earthquake loads. By examining the p-value and the residual distribution, the results show that the predictive values are reasonable. The proposed predictive model is validated by the measured data.
高广运, 石超, 陈青生. 地震荷载等效循环周数的预测模型[J]. 岩土工程学报, 2015, 37(11): 2040-2044.
GAO Guang-yun, SHI Chao, CHEN Qing-sheng. A predictive model on equivalent number of strain cycles for earthquake loads. Chinese J. Geot. Eng., 2015, 37(11): 2040-2044.
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