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离散元方法在混凝土准静态和动态材料行为方面的潜力，并深入了解裂纹演化和损伤机制。其目的特别包括使用一种相同的基本模型方法和基本相同的模拟代码来研究不同负载条件下的材料行为。 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样本。用于计算相互作用粒子的接触力的基础接触方法和接触方法的参数是唯一的先验假设。不包括有关潜在裂缝和损坏模型的假设或元素。相反，基于破碎和细观结构重排的效应是模拟的结果。此外，离散元模拟适用于分析冲击情况下发生的高加载速度下的材料行为。由于基于粒子的特性以及牛顿第二定律的使用，DEM 模拟允许对与混凝土中冲击波传播相关的复杂动态现象进行定性和定量研究。作为该项目的一部分，将进一步开发离散元模拟，并使用用于实验室实验构思和设计的数值工具。实验结果的解释和外推是离散元数值模拟的进一步应用。计划在拟议的项目阶段内使用虚拟均质样本和细观结构样本进行准静态载荷和冲击载荷下的研究以及应变率效应的研究。