Canadian Geotechnical Journal, Ahead of Print.
Various undrained cavity expansion solutions for elastic–plastic soil have been proposed previously. However, no solution has been presented for elastic–viscoplastic (EVP) soil until now. This paper presents a general solution method for solving the classical one-dimensional (1D) boundary value problem (BVP) for undrained cylindrical or spherical cavity expansion in EVP soil with an emphasis on the rate effect of soil. The solution method is summarized as three standard procedures: (i) obtaining the soil displacement and strain under incompressible conditions, (ii) calculating the effective stress of soil through a suitable constitutive law, and (iii) obtaining the pore pressure by numerically solving the stress equilibrium equation through the finite difference method (FDM) or other numerical solution techniques. The numerical algorithms for calculating the effective stress and pore pressure are very simple, without any complex iteration processes, and they require little calculation time but provide high computational accuracy. In addition, some numerical results are given to investigate the influence of the cavity expansion velocity on the cavity expansion response. The proposed solution procedure is general and can be applied not only for the EVP model but also for other plasticity models, and the given EVP solution can be applied to interpret the rate effect of the cone penetration test and pile penetration.

中文翻译：

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弹-粘塑性土中不排水的圆柱形和球形空腔膨胀

加拿大岩土工程杂志，提前印刷。
之前已经提出了各种弹塑性土的不排水腔膨胀解决方案。然而，到目前为止，还没有针对弹性粘塑性 (EVP) 土提出解决方案。本文提出了求解 EVP 土壤中不排水圆柱形或球形空腔膨胀的经典一维 (1D) 边界值问题 (BVP) 的通用求解方法，重点是土壤的速率效应。求解方法概括为三个标准程序：(i) 获得不可压缩条件下的土壤位移和应变，(ii) 通过合适的本构法则计算土壤的有效应力，以及 (iii) 通过数值求解通过有限差分法 (FDM) 或其他数值求解技术求解应力平衡方程。计算有效应力和孔隙压力的数值算法非常简单，没有复杂的迭代过程，计算时间少，计算精度高。此外，还给出了一些数值结果来研究腔膨胀速度对腔膨胀响应的影响。所提出的求解程序是通用的，不仅可以应用于 EVP 模型，还可以应用于其他塑性模型，并且给定的 EVP 解决方案可用于解释锥入试验和桩穿透的速率效应。给出了一些数值结果来研究腔膨胀速度对腔膨胀响应的影响。所提出的求解程序是通用的，不仅可以应用于 EVP 模型，还可以应用于其他塑性模型，并且给定的 EVP 解决方案可用于解释锥入试验和桩穿透的速率效应。给出了一些数值结果来研究腔膨胀速度对腔膨胀响应的影响。所提出的求解程序是通用的，不仅可以应用于 EVP 模型，还可以应用于其他塑性模型，并且给定的 EVP 解决方案可用于解释锥入试验和桩穿透的速率效应。