A novel experimental system for studying the sand liquefaction characteristics from macroscopic and microscopic points of view

Abstract

A novel experimental system for studying the macro- and micro-liquefaction behaviors of sand deposits was designed, developed, and applied in this paper. The developed system mainly consists of a shaking table sub-system, a visualized model container, and a fast-shutter-speed micro-image acquisition sub-system. Liquefaction tests on saturated Fujian sand deposit with less permeable Zhuhai clay overburden were conducted to check the performances of the system and study the micro-liquefaction behaviors. Throughout the total liquefaction process, the excess pore water pressures and micro-liquefaction images were recorded and analyzed. It was shown that satisfactory performances can be provided by the developed experimental system. The results showed that the obtained micro-fabrics of sand particles (i.e., the orientations of the contact normal and the long axis of sand particles, the average contact number, and apparent void ratio) agree well with the macro behaviors (i.e., the excess pore water pressure) throughout the total process of liquefaction. Void redistribution during liquefaction was observed beneath the overburden. The developed novel experimental system helps to illuminate the mechanisms of sand liquefaction from the micro-perspective.