Abstract In this paper, a fully Lagrangian particle-based method for coupled fluid-particle interaction is utilized to evaluate liquefaction of saturated granular soils subjected to dynamic base excitations. The discrete element method (DEM) is employed to model the solid particles and the fluid motion is simulated using the smoothed particle hydrodynamics (SPH). A coupled SPH-DEM scheme is achieved through local averaging techniques and well-established semi-empirical formulas for fluid-particle interaction. A key feature of the employed technique is that it does not presume undrained conditions for the granular deposit and allows for spatial fluid movements within the deposit. The responses of loose and dense granular deposits to seismic excitation are first analyzed. As expected, the loose deposit exhibited significant pore pressure development and liquefaction while the dense deposit barely showed any considerable buildup of pore pressure and did not liquefy. Liquefaction of the loose deposit resulted in significant surface settlement while that experienced by the dense deposit was within tolerable limits. A liquefaction mitigation technique through the installation of gravel drains was then introduced to the loose deposit and its effect on mitigating pore pressure buildup was examined. Results of conducted simulations show that the installation of gravel drains effectively reduced pore-pressure buildup and, for the most part, the soil maintained its strength. However, the drains did not reduce the overall surface settlement of the deposit to acceptable levels.

中文翻译：

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土壤液化的耦合光滑粒子流体动力学-离散元方法模拟及其使用砾石排水的缓解

摘要 在本文中，一种完全基于拉格朗日粒子的耦合流体 - 粒子相互作用的方法被用来评估受到动态基础激励的饱和颗粒土的液化。离散元法 (DEM) 用于模拟固体颗粒，并使用平滑颗粒流体动力学 (SPH) 模拟流体运动。耦合 SPH-DEM 方案是通过局部平均技术和完善的流体 - 粒子相互作用半经验公式实现的。所采用技术的一个关键特征是它不假定粒状沉积物的不排水条件，并允许沉积物内的空间流体运动。首先分析松散和致密颗粒沉积物对地震激发的响应。正如预期的那样，松散沉积物表现出显着的孔隙压力发展和液化，而致密沉积物几乎没有表现出任何显着的孔隙压力增加并且没有液化。松散沉积物的液化导致显着的地表沉降，而致密沉积物的液化在可接受的范围内。然后通过安装砾石排水管将液化缓解技术引入松散沉积物，并检查其对缓解孔隙压力增加的影响。进行的模拟结果表明，砾石排水管的安装有效地降低了孔隙压力的积累，并且在大多数情况下，土壤保持了其强度。然而，排水管并没有将沉积物的整体表面沉降降低到可接受的水平。