本工作的重点是约束混凝土在多轴载荷作用下的非线性材料响应的数值模拟。特别地，这里提出了一种改进的回归映射程序来处理屈服面中的奇异点(角点)问题，能够局部地捕获有效屈服面上的最优回归点。该算法应用于测温法和Willam屈服面，具有Grassl提出的塑性势和Cervenka提出的适用于混凝土材料的软化定律。本文讨论了模拟混凝土约束行为、峰后行为以及预测其完全塑性或软化的模型能力。该方法可应用于沿静压轴的任何具有奇异屈服面的弹塑性材料。

原文题目：Apex control within an elasto-plastic constitutive model for confined concretes

原文：This work focuses on the numerical modelling of confined concretes when subjected to multiaxial loading accounting for a nonlinear material response. Particularly, an improved return mapping procedure is here presented to cope with the issue of singularities (corners) in the yield surface, able to catch locally the optimal return point on the active yield surface. The algorithm is applied to the Menetry and Willam's yield surface, with a plastic potential as suggested by Grassl and the softening law proposed by Cervenka suitable for concrete materials. The model capabilities to reproduce the confined behaviour of concrete, as well as its post-peak behaviour, and to predict perfect plasticity or softening are here discussed. The proposed approach can be applied to any elastoplastic material with singular yield surface along the hydrostatic axis.

原文作者：Gianluca Mazzucco, Beatrice Pomaro, Valentina A. Salomoni, Carmelo E. Majorana

原文地址：https://arxiv.org/abs/2003.05872