光面钢筋拉拔试验细观数值模拟研究

Research on Mesoscale Numerical Simulation of Smooth Rebar Pullout Test

从钢筋-混凝土界面的细观粘结机理出发,把化学胶结力、机械咬合力的弱化过程看成损伤过程,对其进行了库仑摩擦模拟;考虑混凝土的非均质特性,并假定其界面细观单元力学特性服从Weibull分布,对光面钢筋的拉拔试验进行了数值模拟,并对随机生成的100组试件的细观数值模拟结果进行了统计分析。结果表明:计算结果与试验结果吻合良好,拉拔强度呈正态分布,拉拔强度的均值接近于规范建议值,验证了模型的合理性。

On the basis of the interface bonding mechanism between rebar and concrete, the weaken process of the chemical adhesive force and the machinery bite force was taken as a damage process. After that, the friction force would become the main force between rebar and concrete, which would be simulated by Coulomb friction model. Furthermore, Weibull distributed parameters were also used in the analysis to describe the inhomogeneity of the interface. Finally, based on statistical analysis on the mesoscale numerical simulations of 100 sets of random test specimens, the smooth rebar debonding procedure in the pullout test was numerically simulated. The results show that the calculation results coincide well with the test results, the tensile strength shows normal distribution and its mean value meets well with the advice value in specification, which can validate the rationality of the model.