Dynamic characteristics of marine soft clay under variable phase difference and initial static shear stress

Abstract

Under seismic loading, the soil layer is subjected to multidirectional cyclic shear stress with different amplitudes and frequencies because of the coupling of multiple shear waves and the soil element within a slope or behind a retaining wall is subjected to initial static shear stress before subjected to cyclic loading. Due to the complexity of seismic loading propagation, a phase difference exists between the initial static shear stress and cyclic shear stress. To investigate the influence of the phase difference and initial static shear stress on cyclic shear strain, cyclic modulus, and cyclic strength, a series of laboratory tests are performed on Wenzhou marine soft clay by multi-directional simple shear system, which can simulate the actual state better by controlling the horizontal cyclic stress in the x and y directions simultaneously. As the phase difference varies from 0° to 90°, the dynamic shear modulus increases and cyclic strain accumulation decreases with an increasing number of cycles. The shear strain increases with the initial shear stress.     

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印度海上战略通道的新动向、动因及影响

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海洋中的烃及其迁移和衰变

对海洋中有关烃类的研究工作进行回顾和总结，分别介绍海洋中烃的来源，迁移和衰变及石油对海洋的污染。     

海洋遥感的应用与展望

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渤海海洋线虫与底栖桡足类数量之比的应用研究

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长江三角洲北翼全新统底界和“硬粘土层”的讨论

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西菲律宾海沉积物铁族元素地球化学

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