Abstract Direct numerical simulation based on experimental stress–strain data without explicit constitutive models is an active research topic. In this paper, a mechanistic-based, data-driven computational framework is proposed for elastoplastic materials undergoing finite strain. Harnessing the physical insights from the existing model-based plasticity theory, multiplicative decomposition of deformation gradient and the coaxial relationship between the logarithmic trial elastic strain and the true stress is employed to perform stress-update, driven by two sets of the specifically measured one dimensional (1D) stress–strain data. The proposed approach, called MAP123-EPF, is used to solve several Boundary-Value Problems (BVPs) involving elastoplastic materials undergoing finite strains. Numerical results indicate that the proposed approach can predict the response of isotropic elastoplastic materials (characterized by the classical J2 plasticity model and the associative Drucker–Prager model) with good accuracy using numerically/experimentally generated data. The proposed approach circumvents the need for the several basic ingredients of a traditional finite strain computational plasticity model, such as an explicit yielding function, a hardening law and an appropriate objective stress rate. Demonstrative examples are shown and strengths and limitations of the proposed approach are discussed.

中文翻译：

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MAP123-EPF：一种基于力学的数据驱动的有限应变数值弹塑性建模方法

摘要 基于实验应力-应变数据而无需显式本构模型的直接数值模拟是一个活跃的研究课题。在本文中，针对承受有限应变的弹塑性材料提出了一种基于力学的、数据驱动的计算框架。利用现有的基于模型的塑性理论的物理见解，变形梯度的乘法分解以及对数试验弹性应变与真实应力之间的同轴关系被用来进行应力更新，由两组专门测量的一维驱动(1D) 应力应变数据。所提出的方法称为 MAP123-EPF，用于解决涉及承受有限应变的弹塑性材料的几个边界值问题 (BVP)。数值结果表明，所提出的方法可以使用数值/实验生成的数据以良好的精度预测各向同性弹塑性材料的响应（以经典的 J2 塑性模型和关联的 Drucker-Prager 模型为特征）。所提出的方法避免了对传统有限应变计算塑性模型的几个基本成分的需求，例如显式屈服函数、硬化定律和适当的客观应力率。展示了示范性示例，并讨论了所提议方法的优势和局限性。所提出的方法避免了对传统有限应变计算塑性模型的几个基本成分的需求，例如显式屈服函数、硬化定律和适当的客观应力率。展示了示范性示例，并讨论了所提议方法的优势和局限性。所提出的方法避免了对传统有限应变计算塑性模型的几个基本成分的需求，例如显式屈服函数、硬化定律和适当的客观应力率。展示了示范性示例，并讨论了所提议方法的优势和局限性。