Peng Yijiang, Wang Qing, Ying Liping, Kamel Mahmoud M A, Peng Hongtao
Key Laboratory of Urban Security and Disaster Engineering, Ministry of Education, Beijing University of Technology, Beijing ,100124, China.
Department of Civil Engineering, Faculty of Engineering, Fayoum University, 63514 Fayoum, Egypt.
Materials (Basel). 2019 Feb 20;12(4):643. doi: 10.3390/ma12040643.
Based on the base force element method (BFEM), the dynamic mechanical behavior of concrete under uniaxial compression loading at different strain rates is investigated. The concrete can be considered as a three-phase composite material composed of aggregate, cement mortar, and interfacial transition zone (ITZ) on the meso-level. A two-dimensional random aggregate model is generated by the Monte Carlo method. A multi-linear two-dimensional damage model is applied to describe the damage properties of each phase in the concrete. The strain-softening behavior, strain-rate effect, and failure patterns of the concrete are studied. The numerical results find that the peaks of compressive stress and compressive strain of concrete show the rate-sensitivity in various degrees under different strain rates. The calculated results of the dynamic enhancement factors are in a good agreement with the formula given by the Comité Euro-International du Béton (CEB) and other experimental results. The failure diagram of the specimen clearly describes the compressive failure process of the concrete specimen. This failure's characteristics are similar to the experimental results.
基于基力元法（BFEM），研究了混凝土在不同应变率下单轴压缩加载下的动态力学行为。在细观层面上，混凝土可被视为由骨料、水泥砂浆和界面过渡区（ITZ）组成的三相复合材料。通过蒙特卡洛方法生成二维随机骨料模型。应用多线性二维损伤模型来描述混凝土中各相的损伤特性。研究了混凝土的应变软化行为、应变率效应和破坏模式。数值结果表明，在不同应变率下，混凝土的抗压应力峰值和抗压应变峰值在不同程度上表现出率敏感性。动态增强因子的计算结果与欧洲国际混凝土委员会（CEB）给出的公式以及其他实验结果吻合良好。试件的破坏图清晰地描述了混凝土试件的受压破坏过程。这种破坏特征与实验结果相似。
