The contribution at hand introduces a novel formulation that couples the Material Point Method (MPM) and Finite Element Method (FEM) based on nonlocal mechanics using an implicit time integration scheme. A constitutive formulation at finite deformations to describe fiber-reinforced concrete is applied. A damage approach within the microplane framework is utilized to capture the induced anisotropy in concrete structures. Furthermore, the microplane model is able to capture the initial anisotropy due to fiber inclusion. In addition, an implicit gradient enhancement is utilized to overcome problems of numerical instabilities when modeling softening phenomena. Numerical examples are presented to demonstrate the capability of this new approach to couple the mechanical and nonlocal fields between MPM and FEM in a reliable and physical manner.

中文翻译：

---

耦合隐式 MPM-FEM 中的隐式梯度增强微平面损伤材料模型


手头的贡献引入了一种新的公式，它使用隐式时间积分方案将基于非局部力学的物质点法 （MPM） 和有限元法 （FEM） 耦合在一起。应用有限变形时的本构公式来描述纤维增强混凝土。利用微平面框架内的损伤方法来捕获混凝土结构中的诱导各向异性。此外，微平面模型能够捕获由于纤维夹杂引起的初始各向异性。此外，在模拟软化现象时，利用隐式梯度增强来克服数值不稳定性问题。通过数值示例，证明了这种新方法能够以可靠的物理方式耦合 MPM 和 FEM 之间的机械场和非局部场。