A simplified model of equivalent calculated pile length for pile–soil–structure interaction analysis
(2.School of Civil Engineering, Shandong Jianzhu University, Jinan, Shandong Province, China 250101)
【Abstract】To a certain extent, the pile length is one of the key factors affecting the complexity of the dynamic analysis of the pile–soil–structure system. A proper simplification for the pile length can improve the calculation efficiency, especially for a structural system with a large number of long pile foundations. Based on Boulanger model and OpenSees, this study analyzed the earthquake response of the single pile–soil–structure system in the soft clay site, including the displacement, bending moment, shear force of the pile and the acceleration response of superstructure, and investigated the variation of vibration modes and mode periods with different pile lengths, and then proposed a pile–soil–structure model with equivalent calculated length pile. The results show that the model with equivalent calculated length pile has high simulating accuracy, and the calculation error of the dynamic response of structure system is less than 5% when the change rate of the first three-mode periods of structure system is lower than 2.5%; the equivalent calculated pile length can be determined by the accuracy requirement of the dynamic response error, and for the single pile structure in the soft clay site, it is suggested that the corresponding calculated pile length should be regarded as the equivalent calculated pile length when the change rate of the first three-mode periods is controlled to 2.5%.
【Keywords】 Pile–soil–structure interaction; equivalent calculated pile length; simplified model; change rate of vibration mode period; Boulanger model; OpenSees;
(Translated by LIU T)
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