物质点法在椭圆骨料混凝土损伤模拟中的应用

Application of material point method in damage simulation of elliptical aggregates concrete structure

为研究混凝土结构的宏观力学响应及损伤行为,应用物质点法这一新型数值方法对椭圆骨料混凝土进行数值模拟研究。基于蒙特卡罗模拟方法,考虑混凝土的细观结构,提出了一种构建随机椭圆骨料混凝土细观几何模型的方法。在该几何模型的基础上,进一步提出一种快速建立混凝土细观物质点模型的方法。分别以弹塑性损伤本构模型和弹性本构模型模拟砂浆和骨料的力学行为,采用开发的物质点法程序对混凝土数值模型进行了单轴拉伸及单轴压缩数值试验。结果表明,物质点法模拟所得的结果与设计规范及有限元结果相近。可见,物质点法为混凝土结构损伤行为的数值模拟提供了一条可行的途径。

In order to study the macro mechanical response and damage behaviors of concrete structures,the material point method(MPM)was applied to numerical simulation of elliptical aggregate concrete.Based on the Monte Carlo simulation method and considering the mesostructure of concrete,a method of constructing the meso-geometric model of concrete with random elliptical aggregate was proposed.Then,on the basis of the geometric model,a method of fast establishing the meso-material point model of concrete was proposed.The mechanical behaviors of mortar and aggregate were simulated by elastoplastic damage constitutive model and elastic constitutive model respectively.The numerical model of concrete under uniaxial tension and uniaxial compression was tested by the material point method program.The results show that the simulation results obtained by the material point method were similar with those obtained by the design code and the finite element method.It can be seen that the material point method provides a feasible way for numerical simulation of damage behavior of concrete structures.