ABSTRACT

Centrifuge shaking table tests were conducted to reveal the intrinsic mechanisms of the effects caused by complicated seismic histories on the liquefaction resistance of a saturated sand deposit. The centrifuge model was shaken by a well-designed seismic sequence including 16 shakings in a certain order. Macroscopic and mesoscopic dynamic responses of the sand deposit were measured and analyzed. Experimental results demonstrated that seismic histories had positive or negative effects on sand liquefaction resistance though sand was densified after previous shakings; these effects were well indicated by the changes in anisotropy characteristics of sand fabric caused by the previous shakings.

摘要

为了揭示复杂的地震历史对饱和砂层液化阻力影响的内在机制，进行了离心振动台试验。离心机模型通过精心设计的地震序列进行震动，包括按一定顺序进行的 16 次震动。对砂层的宏观和细观动态响应进行了测量和分析。实验结果表明，虽然沙子在前次震动后致密化，但地震历史对沙子的抗液化能力有正向或负向影响；这些影响从先前的震动引起的砂织物各向异性特性的变化中得到了很好的体现。