عنوان مقاله [English]
Detonation of explosives in saturated sandy soils generates high-intensity compressive stress waves. These stress waves cause a significant increase in pore water pressure and a decrease in effective stress that may cause soil liquefaction. Therefore, understanding the mechanism of explosion-induced soil liquefaction development and how to decrease its damages can be vitally
important for geotechnical and passive defense engineers. Because of the complex structure of soil, high amplitude blast loading, short time of detonation, high strain and pore water pressure, the numerical modeling of explosion-induced liquefaction is very complicated. Moreover, experimental results are highly dependant on the site condition and methods of experiment. In this paper, an explosion-induced soil liquefaction phenomenon has been simulated in three-dimensional space using LS-DYNA V971 R4.2 explicit dynamic nonlinear finite-element analysis code. To model soil properties in these analyses, MAT-FHWA-SOIL saturated sandy soil has been used which is available in LS-DYNA code with the modified Mohr-Coulomb behavior. To apply blast loading, a buried cylindrical explosive charge located on the axis of symmetry of the model has been used. The JWL equation of state has been applied to simulate blast phenomenon. In addition to numerical modeling of explosion-induced soil liquefaction phenomenon, parametric studies have been conducted for the investigation of effects of parameters in relation to soil properties and loading conditions on the generation of residual excess pore water pressure. The obtained results from this research demonstrate that increasing the skeleton bulk modulus of the soil leads to the increasing residual excess pore water pressure. Soil parameters, such as cohesion, maximum, and residual internal friction angle, are the factors that have no effect on the generation of residual excess pore water pressure.