【摘要】 用二维梁-颗粒模型BPM2D(Beam-Particle Model in Two dimensions)模拟了混凝土动态破坏过程.梁-颗粒模型BPM2D是在离散元法基础上,结合有限元法开发的二维数值计算模型. 在模型中用三种类型梁单元形成混凝土数值试样.每种类型梁单元的力学性质均按韦伯(Weibull) 分布随机赋值以模拟混凝土细观结构的非均匀性,同时梁单元的强度随应变率不同而变化.利用此模型分析了混凝土板在弹体冲击条件下的破坏过程,并给出不同弹体初始速度条件下混凝土内部应力波传播过程.通过将计算结果与实验数据相比较,表明梁-颗粒模型可有效应用于计算和模拟脆性材料动态破坏问题.更多还原

【Abstract】 The dynamic fracture process of concrete is simulated with the BPM2D(Beam-Particle Model in Two Dimensions) which is based on DEM in combination with FEM. In the BPM2D three types of beam are chosen to be the concrete specimens to simulate. The mechanical properties of the elements of each and every beam vary with their strain-rate and are randomly assigned according to Weibull distribution so as to model the initial heterogeneity of concrete at microscale level. The failure process of a concrete panel under dynamic impact was analyzed by this model. The stress wave propagation in concrete at different impact velocities was displayed. A comparison of the simulated results with experimental data declares that the BPM2D is available to simulate the dynamic failure of brittle materials.更多还原