Abstract:The liquefaction characteristics and anti-liquefaction treatment measures of coral sand sites are one of the key issues in the construction of tropical ports. Based on the dynamic centrifuge model parallel test,the seismic liquefaction characteristics of coral sand and standard sand in free fields are analyzed from the aspects of excess pore water pressure ratio,site amplification effect,surface subsidence,shear modulus and damping ratio. The results show that the load intensity triggering liquefaction of coral sand site is significantly higher than that of standard sand site,and the liquefaction depth is significantly lower than that of standard sand site under the same conditions. The acceleration amplification coefficient of coral sand site is obviously smaller than that of standard sand under the loads of 0.2 g and 0.3 g sine wave. The cumulative surface subsidence of coral sand site is about 2/3 of that of standard sand site under 0.05 g–0.3 g sequence loads. In liquefied soil layer,the shear strain of coral sand site is higher than that of standard sand site and the shear stress is lower than that of standard sand site. In the non-liquefied soil layer,under the strong loads of 0.2 g and 0.3 g sine wave,the shear stress and shear strain of coral sand site are smaller than that of standard sand. The attenuation rate of shear modulus of coral sand site with shear strain is faster than that of standard sand site under the same conditions. The damping ratio of coral sand site is slightly smaller than that of standard sand site under 0.05 g–0.3 g sequence loads. The research results provide important guidance basis and rich data for understanding the liquefaction characteristics of coral sites and designing the anti-liquefaction behavior of port engineering.
陈平山1,2,梁小丛1,2,王体强3,4,王德咏1,2,王永志3,4,樊 旭3,4,陈卓识3,4,袁晓铭3,4. 珊瑚礁砂与标准砂场地液化特征动力离心试验研究[J]. 岩石力学与工程学报, 2023, 42(9): 2283-2294.
CHEN Pingshan1,2,LIANG Xiaocong1,2,WANG Tiqiang3,4,WANG Deyong1,2,WANG Yongzhi3,4,. Dynamic centrifuge model test study on liquefaction characteristics of #br#
coral sand and standard sand #br#. , 2023, 42(9): 2283-2294.
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