【摘要】 地震动使海底倾斜土层软化、液化并产生永久变形和位移。基于有限元理论,提出一种海底缓坡场地地震引起水平侧移的数值计算方法,将波浪荷载简化为恒定压力荷载和初始孔压,采用二维有效应力动力有限元分析方法进行液化分析,同时由模量软化理论得到土层在地震动各时段的模量,通过非线性静力方法计算软化、液化引起的水平侧移。由算例分析了土层坡度、液化层及上覆非液化层厚度、波浪荷载等因素对侧移的影响,通过对比分析表明了该方法的有效性,可为近海工程场地地震地质灾害评价提供参考数据。更多还原

【Abstract】 Soil softening and liquefaction due to earthquake cause permanent deformations and displacements of submerged slope. Based on finile element theory, a numerical method for lateral displacement analysis of submerged gentle slope is presented. Wave loads are simplified as constant pressure and initial pore pressure. Liquefaction analysis is performed by 2-d dynamic effective stress finite element method. In each time segment, gradually softened modulus are calculated based on module soften theory; lateral displacements analysis are performed with the new modulus by nonlinear static method. By examples, the influences on lateral displacements are studied with different slope angles, wave loads, thicknesses of liquefied layers and surface non-liquefied layers. Compared with the results of other researches, the validity of the new method was confirmed and it is applicable to solutions of earthquake geological hazards evaluating in offshore engineering field.更多还原