初始孔压非均布考虑起始比降的一维固结解

Solution for one-dimensional consolidation with threshold gradient subjected to non-uniformly distributed initial pore water pressure

研究了考虑起始比降的一维固结问题,获得了初始孔压非均布条件下考虑起始比降的一维固结解答,并与已有文献解答进行了对比,讨论了考虑起始比降后土体的一维固结特性。计算分析表明,当初始孔压降小于起始比降时,渗流并不会在整个土层中瞬间发生,而是逐渐向下发展的,起始比降越大,渗流边界移动速度越慢;固结结束时,土体中的孔隙水压力并不会完全消散,且起始比降越大,残余孔隙水压力越大。与不考虑起始比降不同,均质地基平均固结度按沉降定义和按孔压定义是不同的,随着起始比降的增大,按沉降定义的固结度随之增大,而按孔压定义的固结度则随之减小。

An analytical solution is obtained for the one-dimensional consolidation problem considering the threshold gradient.The proposed solution is compared with previous solutions.The results show that the proposed approach is reasonable.Based on the solution,the consolidation behaviors of the ground are discussed.The results show that when the initial pore pressure gradient is less than the threshold gradient,the flow will not occur throughout the whole layer instantaneously but rather gradually from top to bottom.The greater the threshold gradient is,the slower the boundary of seepage moves.The excess pore pressure will not be completely dissipated at the end of consolidation.The greater the threshold gradient is,the larger the residual excess pore pressure is.It is shown that,unlike without the threshold gradient,the average degree of consolidation defined by settlement considering the threshold gradient is different from that defined by pore pressure.The greater the threshold gradient,the larger the average degree of consolidation defined by settlement and the smaller that defined by pore pressure.