论文部分内容阅读
为了探讨再生混凝土中各相力学性能对其宏观力学性能的影响、寻找改善再生混凝土静力与疲劳性能的有效途径,基于ABAQUS软件建立了九骨料模型再生混凝土的有限元模型,并对各相材料赋予不同的损伤本构.分别采用显式准静态分析步和直接循环分析步对九骨料模型再生混凝土的单轴受压静力和低周疲劳加载进行数值模拟,并将静力性能仿真结果与试验结果进行对比.变参数分析结果表明:静力性能仿真结果与试验结果吻合较好;模型再生混凝土在界面过渡区会产生明显的应力集中现象,导致界面区砂浆塑性变形加剧,促使裂纹产生和扩展;随着再生粗骨料取代率的降低,模型再生混凝土的单轴受压强度和峰值应变逐渐增大;随着新砂浆强度的提高,模型再生混凝土的单轴受压强度逐渐增大;模型再生混凝土的疲劳性能较再生混凝土低,且应力-疲劳寿命曲线的趋势与普通混凝土相近.
In order to investigate the influence of the mechanical properties of recycled concrete on its macroscopic mechanical properties and find an effective way to improve the static and fatigue properties of recycled concrete, a finite element model of recycled aggregate concrete based on ABAQUS software was established. The materials are given different damage constitutive models.Experimental static analysis steps and direct cycle analysis steps are used to simulate the uniaxial compressive and low cycle fatigue loadings of recycled aggregate concrete with nine aggregates respectively and to simulate the static performance The results of the comparison with the test results show that the results of the static performance simulation agree well with the experimental results, and the obvious stress concentration will occur in the transition zone of the model recycled concrete, resulting in aggravating plastic deformation of the mortar in the interface zone and promoting the crack The uniaxial compressive strength and peak strain of recycled concrete gradually increase with the decreasing of the replacement rate of recycled coarse aggregate. The uniaxial compressive strength of recycled concrete increases with the increase of new mortar strength The fatigue performance of model recycled concrete is lower than that of recycled concrete, and the trend of stress-fatigue life curve and Ordinary concrete is similar.