Abstract In this paper, a novel elastoplastic solution is developed for the undrained expansion of a spherical cavity in overconsolidated soils, with the aim of providing a mechanical model for the interpretation of cone penetration tests in overconsolidated soils. The well-established unified hardening (UH) model is adopted in the present solution to represent the unique mechanical behaviors of the overconsolidated soil during cavity expansion. The problem considered is formulated as a system of first order partial differential equations in terms of a Lagrangian description; these equations are solved as an initial value problem with the code developed based on the Runge-Kutta algorithm. The results, including the expansion-pressure curves, the distributions of the stress components, and the evolution of the potential strength during cavity expansion are presented to show the expansion responses in overconsolidated soils. The results reveal that the unique expansion responses in overconsolidated soil during cavity expansion, such as the development of a negative excess pore water pressure, the strain-hardening and softening behavior, the peak strength and the decay of the potential strength during cavity expansion could be well represented by the present solution.

中文翻译：

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超固结土中球腔不排水膨胀的弹塑性解决方案

摘要 在本文中，针对超固结土中球形空腔的不排水膨胀问题，提出了一种新的弹塑性解决方案，旨在为超固结土中锥入度试验的解释提供力学模型。本解决方案采用完善的统一硬化 (UH) 模型来表示超固结土在空腔膨胀过程中的独特力学行为。所考虑的问题根据拉格朗日描述被表述为一阶偏微分方程组；这些方程作为初值问题使用基于 Runge-Kutta 算法开发的代码求解。结果，包括膨胀压力曲线，应力分量的分布，并给出了空腔膨胀过程中潜在强度的演变，以显示超固结土中的膨胀响应。结果表明，超固结土在空腔膨胀过程中的独特膨胀响应，如负超孔隙水压力的发展、应变硬化和软化行为、空腔膨胀过程中的峰值强度和潜在强度的衰减可能是本解决方案很好地代表了这一点。