摘要针对吹填土地基大应变固结课题涉及材料非线性、几何非线性等复杂问题,基于孔隙比e与土体有效应力、渗透系数之间的对数函数关系,结合以往研究中的一维大应变固结方程,推导简化后的固结方程,并分别对自重固结(单面排水、双面排水)及正常固结(单面排水、双面排水)问题进行深入研究,结合相应初始及边界条件,利用函数变换法及分离变量求解法,分别给出孔隙比、总平均固结度的解析解,通过与P. J. Fox中算例CS2模型计算成果对比验证分析,认为自重固结双面、单面排水情况的计算孔隙比分别选取第一分层、第二分层(总10分层)的最终平均孔隙比时,该解析解的总固结度曲线及不同时刻孔隙比与CS2模型计算成果的吻合性较好,基本满足工程实践应用精度要求;最后通过舟山市某吹填工程的相关试验监测资料对比分析,表明该理论成果具有一定工程应用价值。
Abstract:The problem of large-strain consolidation of saturated soft soil foundations is complex,such as material nonlinearity and geometrical nonlinearity,and it is generally difficult to get analytical solutions. Based on the relationship between the porosity and the effective stress and permeability coefficient of the soil,combined with the one-dimensional large-strain consolidation equation proposed by Gibson,the consolidation equation was implified. Then,the separates self-weight consolidation and normal consolidation problems were studied under the corresponding initial and boundary conditions. The analytical solution is verified by the calculation results of the CS2 model of the example in Fox,which calculated porosity ratio of double-sided with self-consolidation with the first layer,and single-sided drainage with the second layer(total 10 layers). The results revealed that the total consolidation degree curve of the analytical solution and the corresponding moment porosity are in good agreement with the calculation results of the CS2 model. Finally the theory has a certain value engineering in the comparative analysis of a reclamation project.
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