特殊条件下考虑起始比降的一维固结解析解

Analytical solution for one dimensional consolidation with considering initial gradient under special condition

针对考虑起始比降的一维固结问题,假定初始孔压降不小于起始比降,分析了考虑起始比降后土体的一维固结特性.采用分离变量法,获得了该条件下考虑起始比降的一维固结精确解并对其进行分析.结果表明:由于起始比降的存在,固结结束时,土中的孔隙水压力不会完全消散,考虑起始比降后,均质地基平均固结度按沉降定义和按平均孔压定义是不同的.起始比降越大,按孔压定义的地基平均固结度越小,当初始孔压呈梯形分布时,按沉降定义的地基平均固结度越大;当初始孔压呈正三角形分布时,按沉降定义的地基平均固结度并不会随着起始比降变化.初始孔压降越小,无论是按沉降定义还是按孔压定义,平均固结度都越大.

For one dimensional consolidation problem with considering the initial gradient,the one dimensional consolidation characteristics for soil with considering initial gradient were analyzed through assuming that the initial pore pressure drop was not less than the initial gradient.An exact solution of one dimensional consolidation with considering the initial gradient under the present condition was obtained and analyzed with the variable separation method.The results show that due to the existence of initial gradient,the pore water pressure in the soil will not completely dissipate at the end of consolidation.With considering the initial gradient,the average consolidation degree defined by settlement for the homogeneous soil is different from that defined by average pore pressure.The greater the initial gradient is,the smaller the average consolidation degree defined by pore pressure is.When the initial pore pressure distributes in a trapezoidal shape,the greater the initial gradient is,the larger the average consolidation degree defined by settlement is.When the initial pore pressure distributes in a regular triangle shape,the average consolidation degree defined by settlement will not change with the initial gradient.The smaller the initial pore pressure drop is,the larger the average consolidation degree defined by both settlement and pore pressure is.