考虑土体水平渗透系数变化的复合地基固结解

为了体现桩体施工扰动对桩周土体造成的负面影响，考虑了排水影响区土体水平渗透性的3种变化模式，即扰动区渗透系数不变、扰动区渗透系数线性变化和整个影响区渗透系数线性变化.采用由平衡条件和等应变假设得到的新的初始条件，分别给出了在各种模式下桩体和土体中的超静孔压的解.将桩体的固结引入复合地基按应力定义的固结度，并分别给出了复合地基按应力和变形定义的总平均固结度.最后分析了4个参数对地基固结性状的影响，并比较了计算结果和文献结果.结果表明，分别按应力和变形定义的总平均固结度相等；土体的最大与最小水平渗透系数之比越大，固结越慢；扰动区范围越小，固结越快；桩体越硬，固结越快.

Analytical solution for consolidation of composite foundation accounting for variation of soil horizontal permeability coefficient

To incorporate the detrimental influence on the surrounding soil due to column installation,three types of variation patterns of the horizontal permeability of soil in the disturbed soil zone were considered,including a constant and a linearly changed permeability coefficient within the disturbed soil zone and a linearly changed permeability coefficient within the whole influence zone.By using a new initial condition derived from the equilibrium condition and the equal strain assumption,the solutions for excess pore water pressure within the surrounding soil and the column were obtained,respectively.The column consolidation was incorporated into the definition of average consolidation degree of a composite foundation.Then the solutions for the total average consolidation degree defined by stress and deformation respectively were put forward.The results indicate that the solution of total average consolidation degree in terms of stress is equal to that in terms of deformation.Finally,the influences of four parameters on the consolidation behavior of composite foundation were analyzed,and several available solutions were compared with the present solution.The results show that the greater the ratio of the maximum to the minimum coefficient of horizontal permeability coefficient of soil is,the slower the consolidation is;the less the size of disturbed soil zone is,the faster the consolidation is;the stiffer the column is,the faster the consolidation is.