简谐线载荷作用下考虑预应力的流体饱和双重孔隙介质层的动力响应  

Dynamic response of a fluid-saturated double-porosity layer with initial stress

作　　者：吴佳平[1] 苏军[1] 赵社戌[1] 

机构地区：[1]上海交通大学船舶海洋与建筑工程学院工程力学系,上海200240

出　　处：《应用力学学报》2015年第4期519-523,699,共5页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金(50978162)

摘　　要：基于Biot型流体饱和双重孔隙介质理论,考虑地基和基岩的预应力,在平面应变条件下研究了下卧垂向不均匀粘弹性半平面基岩的有限厚度双重孔隙地基在简谐线载荷作用下的动力响应。根据Berryman理论,通过引入势函数和运用Helmholtz原理,并利用Fourier变换求解本问题的控制微分方程,得到变换域内应力、位移、孔隙水压力的一般解。结合边界条件,利用Fourier逆变换得到了相应的数值计算结果。结果表明:双重孔隙和半平面的竖向位移随频率、基质孔隙、阻尼因子、不均匀性、预拉应力的增大单调递减;基质孔隙和裂缝孔隙水压力随渗透率的增大单调递减,随频率的增大单调递增。Based on the extended Biot's theory for double-porosity media, the dynamic response of a fluid-saturated double-porosity finite-thickness subgrade with inhomogeneous substratum due to harmonic line loading is investigated theoretically under the condition of plane strain. Effect of Initial stresses in the subgrade and substratum are also considered. By introducing potential functions and applying Helmholtz decomposition theorem, the complementary solutions in transformed domain for stress, displacement and pore pressure are derived after solving governing differential equations by means of Fourier transform. According to the boundary conditions, numerical results are obtained by using the inverse Fourier transform which show vertical displacements decrease with the increase of frequency, matrix porosity, damp coefficient, inhomogeneity parameter and tensile initial stresses, pore pressure increases with permeability decreases and frequency increases.

关 键 词：流体饱和双重孔隙介质 不均匀 预应力 动力响应 

分 类 号：O347[理学—固体力学]