关键词: 液化砂土, 流动效应, 黏滞剪切力, 率相关性, 表观黏度

Abstract: A series of shaking table tests on the saturated sands are conducted. The embedded aluminous tube in the sands is pulled laterally to simulate relative motion between liquefied sands and tube. The theories and methods of fluid mechanics are introduced to analyze the mechanical effects induced by the flows of liquefied sands. The real-time apparent viscosity of liquefied soils and the viscous shear force acting on the tube wall are calculated according to the measured pulling force. Fluid characteristics and flow effects of the liquefied soils are analyzed. For the soils during shaking and after shaking, their flow effects are rate-dependent and dependent on the excess pore water pressure. The influences of initial relative density on the flow effects are also discussed. The experimental results show that apparent viscosity of the liquefied sands is positively correlated with their initial relative density. The apparent viscosity and the viscous shear forces acting on the tube wall are negative correlated with the excess pore water pressure in the soils. Furthermore, the viscous shear forces acting on the tube wall are strongly rate-dependent. Therefore, the rate-dependent soil-structure interaction is suggested to be considered for the seismic analysis of structures in the liquefiable site.

Key words: liquefied sands, flow effects, viscous shear force, rate-dependent, apparent viscosity