为加快固结排水速率并提高地基承载力，组合型复合地基加固技术被广泛应用于地基改良工程，而目前关于此类复合地基的非线性固结理论研究很少。通过对数模型来描述土体的非线性固结特征，并考虑桩-土压缩模量比随固结的变化，建立了散体材料桩-不透水桩复合地基非线性固结解析模型。此外，为减小研究高置换率复合地基固结时产生的计算误差，对传统假定进行修正，并引入新的流量连续性关系来考虑散体材料桩的固结变形。综合考虑散体材料桩井阻效应、桩体施工扰动效应和土体内径-竖向渗流，基于等应变假设和达西定律，推导了该模型的固结控制方程及其解析解。通过参数敏感性分析对复合地基非线性固结特性进行研究，分析了不同荷载形式下各参数对固结性状的影响。此外，与现有模型展开比较研究，并与实测数据进行对比分析，验证了该解答的正确性。结果表明：忽略散体材料桩的桩体固结变形会高估复合地基的固结速率，随着桩体置换率的增加，计算误差最大可达10.5%；当压缩指数Cc小于渗透指数Ckh(v)时，不考虑土体的非线性特征会低估地基固结速率；Cc/Ckv的变化对固结速率的影响很小，与Cc/Ckh相比可以忽略不计；施工场地布置越密集、桩-土压缩模量比越大、散体材料桩渗透系数越大或扰动区半径越小，均会导致地基固结加快。 In order to enhance theground strength and accelerate the consolidation rate

the technique ofcombined composite ground has been widely utilized in ground improvementprojects. However

there are few theoretical investigations on the nonlinearconsolidation behavior of this combined technique. To fill this gap

thelogarithm models of are incorporated to describe the nonlinear consolidationcharacteristics of soils

then an analytical model for the nonlinear consolidationof composite ground with combined use of granular columns and imperviouscolumns is established by accounting for the variation of the column-soilcompression modulus ratio with consolidation. Further

the consolidationdeformation of granular columns is considered by introducing a new flowcontinuity relationship. Based on the equal strain assumption and Darcy’s law

the governing equations and analytical solutions are then obtained withconsideration of the well resistance of granular columns

disturbance effectsof both impervious columns and granular columns and the coupled radial-verticalseepage within soil. Moreover

the present solutions under different loadingschemes are adopted to investigate the influence of several crucial parameterson the nonlinear consolidation behavior of composite ground. Furthermore

theaccuracy of the current model is verified by comparing it with the existingsolutions and applying it to analyze two tests. The results reveal thatignoring column consolidation deformation leads to an overestimate ofconsolidation rate

with maximum error reaching up to 10.5% as the replacementratio increases. Neglecting the nonlinearity will underestimate theconsolidation rate when the soil’s compressive indices Cc are smaller than the permeability indices Ckh(v). Additionally

thevariation of Cc/Ckv has little influence onthe consolidation rate and can be ignored when compared with Cc/Ckh. Factors such as a denser construction site layout

a higher column-soil compression modulus ratio

a larger permeabilitycoefficient

or a smaller smear zone area of granular columns will acceleratethe consolidation of composite ground.