软土地基中群桩稳定性分析是岩土工程的难点之一.通过对饱和软土地基中群桩贯入全过程的力学分析,结合群桩效应与工作性能,根据功能平衡原理,建立了贯入过程中附加应力(含超静孔隙水压力)引起的耗散能量与外力做功、弹性势能三者的平衡关系;同时,针对饱和软土地基中高预应力管桩(PHC)的排土特性,结合现行桩基规范,分别给出了超静孔隙水压力势能、挤土耗散能、重力做功、超静孔隙水压力做功、摩擦耗能、土体弹性势能等的定量表达,构建了PHC群桩贯入过程的能量耗散模型;在此基础上,导出了局部能量安全系数与整体能量安全系数.将上述模型应用于某工程PHC群桩基础的稳定性分析中,并与数值模拟结果对比,验证了该模型的合理可靠性,对饱和软基中PHC群桩稳定性状态的判别具有一定指导意义. The analysis of pile group stability in soft ground is one of the difficulties in geotechnical engineering.According to mechanics analysis of pile group penetration in saturated soft soil foundation and combined with pile group effect and working performance, In the process of penetration, the dissipated energy caused by additional stress (including excessively static pore water pressure) and the balance of the elastic force and elastic energy are also discussed. In the meantime, according to the soil drainage characteristics of high prestressed tubular piles (PHC) in saturated soft soil foundation , Combined with the current code for pile foundation, the quantitative expressions of excess pore water pressure potential energy, soil squeezing energy, gravity work, excess pore water pressure work, friction energy dissipation and soil elastic potential energy are given respectively. The PHC Based on this, the local energy safety coefficient and the overall energy safety coefficient are derived. The above model is applied to the stability analysis of pile foundation of an engineering PHC group, and compared with the numerical simulation results The results show that the model is reasonable and reliable, which is of guiding significance for judging the stability of PHC group pile in saturated soft ground.