Numerical simulations of multiaxial damage behaviour of concrete using the method of discrete elements

混凝土多轴损伤行为的离散元数值模拟

• 批准号: 214361667
• 负责人: Professor Dr.-Ing. Manfred Curbach
• 金额: --
• 依托单位: Institut für Massivbau
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/214361667?language=en
• 关键词: Numerical; simulations; multiaxial; damage; behaviour

The aim of the project is to explore the potential of the discrete element method with regard to the quasi-static and dynamic material behaviour of concrete and to obtain insights into crack evolution and damage mechanisms. The aim includes, in particular, the investigation of material behaviour under different loading conditions using one and the same basic model approach and the principally same simulation code. DEM simulations allow to use the same virtual specimens under different loading conditions and loading velocities. The underlying contact approach which is used for the calculation of the contact forces of interacting particles and the parameters of the contact approach are the only a priori assumptions. No assumptions or elements regarding potential cracks and no damage model are included. Effects based on fragmentation and mesostructural rearrangement are the result of the simulation instead.Furthermore, discrete element simulations are suited for the analysis of the material behaviour under high loading velocities as they occur in impact situations. Due to the particle-based character and due the usage of Newtons second law the DEM simulations allow the qualitative and quantitative study of the complex dynamic phenomena related to the shock wave propagation in concrete. As part of the project, discrete element simulations are to be developed further with a numerical tool for conception and design of laboratory experiments in view. The interpretation and extrapolation of experimental results are further applications of numerical simulations using discrete elements. Investigations under quasi-static load and under impact load using virtual homogeneous specimens and specimens with mesostructure as well as investigations of the strain rate effect are planned within the proposed project phase.

该项目的目的是探索关于混凝土准静态和动态材料行为的离散元方法的潜力，并获得裂缝演化和损伤机制的见解。目的包括，特别是，材料的行为在不同的加载条件下的调查使用一个和相同的基本模型方法和基本相同的模拟代码。DEM模拟允许在不同的加载条件和加载速度下使用相同的虚拟试样。用于计算相互作用粒子的接触力的基本接触方法和接触方法的参数是唯一的先验假设。没有关于潜在裂缝的假设或要素，也没有包括损伤模型。基于碎片化和细观结构重排的效应是模拟的结果。此外，离散单元模拟适合于分析材料在高加载速度下的性能，因为它们发生在冲击情况下。由于基于粒子的特性和牛顿第二定律的使用，DEM模拟可以定性和定量地研究与混凝土中激波传播有关的复杂动力学现象。作为该项目的一部分，离散元模拟将进一步发展，并考虑使用用于实验室实验概念和设计的数值工具。实验结果的解释和外推是离散元数值模拟的进一步应用。拟在项目阶段进行准静态载荷和冲击载荷下使用虚拟均匀试件和具有细观结构的试件的研究以及应变率效应的研究。