Impact of multidirectional shaking on liquefaction potential of level sand deposits
Impact of multidirectional shaking on liquefaction potential of level sand deposits
复制标题
DOI：
10.1680/geot.2008.58.4.259
复制
发表时间：
2008-04
期刊：
影响因子：
5.8
通讯作者：
D. Su;X. Li
中科院分区：
文献类型：
--
作者：
D. Su;X. Li
由多向振动引起的多向剪切不仅涉及剪切大小的变化，而且涉及剪切方向的变化，并且通常涉及与应力不共轴的变形。饱和砂土试件的双轴单剪试验结果表明，加载方向的变化可能会导致无粘性土的抗液化能力显着降低。然而，离心试验结果表明，双向振动对水平砂层液化潜力的影响有限。从数值分析，使用一个完全耦合的地面响应程序（SUMDES），将一个全面的本构模型砂，和塑性理论的基础上的理论研究，它被发现，在原位k0条件，和事实上，在地震下的动剪应力往往会减少超孔隙水压力的建立，减弱水平地面反应的多方向剪切的效果。
Multidirectional shearing, as induced by multidirectional shaking, involves variations not only in shear magnitude but also in shear direction, and in general involves deformations non-coaxial with the stress. Experimental results on saturated sand specimens using a biaxial simple shear device suggest that loading involving changes of direction may introduce significant reduction in the liquefaction resistance of cohesionless soil. However, centrifuge test results indicate that biaxial shaking has only limited impact on the liquefaction potential of level sand deposits. From numerical analysis, using a fully coupled ground response procedure (SUMDES) incorporating a comprehensive constitutive model for sand, and a theoretical study on the basis of the theory of plasticity, it was found that the in situ k0 condition, and the fact that the mobilised shear stress under earthquake tends to decrease as the excess pore pressure builds up, abate the effect of multidirectional shearing on level ground response.