An elastoplastic solution of drained cylindrical cavity expansion is presented based on a well-known critical state model for soils exhibiting a natural structure. The model referred to as the structured Cam-clay (SCC) model is capable of describing the properties of the soil structure and its subsequent stress-induced degradation. The asymmetric stiffness matrix of the elastoplastic constitutive equation for structured soils is derived due to the assumption of the non-associated plastic flow rule. The solution procedure is formulated by transforming the boundary value problem of cylindrical cavity expansion into the problem of solving four ordinary differential equations with three stress components and the specific volume as the basic unknown variables. The theoretical solution is numerically calculated and validated against the existing solution and finite element simulation results. Furthermore, the significance of the soil structure and its stress-induced degradation in the expansion response, and the interaction between the soil structure and overconsolidation are emphasized by extensive parametric analyses. The results demonstrate that the soil structure has a substantial influence on the cavity expansion response, and its degradation is closely related to overconsolidation. Particularly, among the solutions considered, the solution considering the soil structure provides higher effective stress values near the cavity surface due to the additional strength conveyed by the natural structure.

基于众所周知的显示自然结构的土壤的临界状态模型，提出了排水圆柱腔膨胀的弹塑性解。称为结构化凸轮粘土（SCC）模型的模型能够描述土壤结构的特性及其随后的应力诱发的退化。基于非关联塑性流法则的假设，得出结构化土弹塑性本构方程的非对称刚度矩阵。通过将圆柱孔扩张的边值问题转化为以四个应力分量和比容为基本未知变量的四个常微分方程的求解问题来制定求解过程。对理论解进行了数值计算，并针对现有解和有限元模拟结果进行了验证。此外，广泛的参数分析强调了土壤结构及其应力引起的膨胀反应的重要性，以及土壤结构与超固结之间的相互作用。结果表明，土壤结构对空腔膨胀响应有很大影响，其降解与超固结密切相关。特别地，在所考虑的解决方案中，考虑到土壤结构的解决方案由于自然结构传递的额外强度而在模腔表面附近提供了更高的有效应力值。广泛的参数分析强调了土壤结构及其应力诱发的膨胀反应的重要性，以及土壤结构与超固结之间的相互作用。结果表明，土壤结构对空腔膨胀响应有很大影响，其降解与超固结密切相关。特别地，在所考虑的解决方案中，考虑到土壤结构的解决方案由于自然结构传递的额外强度而在模腔表面附近提供了更高的有效应力值。广泛的参数分析强调了土壤结构及其应力诱发的膨胀反应的重要性，以及土壤结构与超固结之间的相互作用。结果表明，土壤结构对空腔膨胀响应有很大影响，其降解与超固结密切相关。特别地，在所考虑的解决方案中，考虑到土壤结构的解决方案由于自然结构传递的额外强度而在模腔表面附近提供了更高的有效应力值。结果表明，土壤结构对空腔膨胀响应有很大影响，其降解与超固结密切相关。特别地，在所考虑的解决方案中，考虑到土壤结构的解决方案由于自然结构传递的额外强度而在模腔表面附近提供了更高的有效应力值。结果表明，土壤结构对空腔膨胀响应有很大影响，其降解与超固结密切相关。特别地，在所考虑的解决方案中，考虑到土壤结构的解决方案由于自然结构传递的额外强度而在模腔表面附近提供了更高的有效应力值。