基于近场动力学理论的混凝土非局部本构建模与渐进破坏研究

项目名称： 基于近场动力学理论的混凝土非局部本构建模与渐进破坏研究

项目编号： No.51209079

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 水利科学与海洋工程学科

项目作者： 黄丹

作者单位： 河海大学

项目金额： 25万元

中文摘要： 混凝土材料和结构的破坏一直是研究者关注的焦点，但其损伤累积和渐进破坏机制尚无法精确描述。本项目引入新兴的适于求解不连续问题的近场动力学（Peridynamics，PD）思想，对混凝土细微观结构进行参数表征和统计分析，基于物质点间的相互作用建立考虑材料细微观结构特征的混凝土积分型非局部PD本构模型；构建相应的混凝土PD模型均质化方法、自适应算法以及误差估计方法，通过求解空间积分方程模拟混凝土结构中损伤累积以及裂纹萌生、扩展、贯通的渐进破坏全过程，突破基于连续介质力学理论的传统方法在模拟破坏问题时的瓶颈；通过不同静、动荷载实验验证混凝土PD本构模型和算法模拟结构渐进破坏的精度与效率；根据数值模拟结果找出混凝土细微观结构参数与宏观力学特性之间的内在联系，分析混凝土破坏的物理机制，为新型高性能混凝土的研发和混凝土结构的安全评估提供科学依据，并为混凝土类复杂非均质材料的损伤破坏模拟提供新的思路。

中文关键词： 混凝土；破坏；近场动力学；非局部模型；微结构

英文摘要： Even though concrete materials and structures have been studied for many years, their failure process has not been fully understood yet. Especially, the progressive failure process in concrete materials and structures cannot be predicted accurately due to the incapability of current available simulation tools. To potentially solve this problem, the objective of the proposed research is to study the effect of microstructures on mechanical behavior of concrete， and shed new light on predictability of damage accumulation and progressive cracking in concrete materials and structures using a novel and promising numerical tool of non-local peridynamics. The proposed study is divided into the following three major tasks:(a) characterizing the microstructures of concrete with experiments and statistical analysis, and developing an integral-type non-local peridynamic constitutive model for concrete correspondingly.(b)establishing the theoretical aspects for homogenization, mesh adaptivity and error estimation under the framework of peridynamics, and then conducting numerical simulations on damage accumulation, crack initiation and propagation in concrete materials and structures. Without using the gradient of displacement in its equation of motions, the non-local peridynamic model in the proposed study can evidently enh

英文关键词： Concrete；Failure；Peridynamics；Non-local Model；microstructure