Laboratory study on flow characteristics of liquefied and post-liquefied sand

Abstract

According to the theory of dropping ball viscosimeter, the test apparatus of flow characteristics of liquefied and post-liquefied sand was developed based on the shaking table test. A steel sphere, which embedded in the sand box, can be moved in the horizontal direction when the soil liquefaction occurred. The resistance force and velocity were measured during the sphere dragging and the apparent viscosity was evaluated. The initial relative density of the deposited sand, the velocity of the sphere and excess pore pressure ratio were the main factors in the tests. The results show that the apparent viscosity of the liquefied and post-liquefied sand is decreasing with the strain rate increasing. The liquefied and post-liquefied sand are shear thinning non-Newtonian fluid. The apparent viscosity of post-liquefied sand is increasing with the excess pore pressure ratio decreasing and the curves slope of the apparent viscosity vs. excess pore pressure ratio is decreasing with the strain rate increasing.

Keywords:

• sand liquefaction
• post-liquefaction
• flow characteristics
• non-Newtonian fluid
• laboratory test

Acknowledgements

This project was supported by the Program for Changjiang Scholars and Innovative Research Team in University (Grant No. IRT1125), the 111 Project (Grant No. B13024), “333 Project” of Jiangsu Province (Grant No. BRA2011146), and the Fundamental Research Funds for the Central Universities (Grant No. 2011B07014).