利用基面力单元法分析再生混凝土端部摩擦效应  

Analysis of Friction Effect on Recycled Concrete Ends Using Base Force Element Method

作　　者：王茜[1] 应黎坪 彭一江[1] 

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京

出　　处：《力学研究》2021年第4期205-214,共10页International Journal of Mechanics Research

摘　　要：本文利用基面力单元法,建立了二维再生混凝土随机骨料细观模型,该模型采用了与界面对齐的Delaunay三角形剖分,模型中的各相材料均采用多折线损伤本构模型,并运用Kupfer双轴强度破坏准则作为双压区损伤的判定依据。其中采用零厚度界面单元考虑了再生混凝土试件与加载垫板之间的摩擦,并讨论了端部摩擦对再生混凝土试件峰值强度和破坏模式的影响。数值结果与前人试验结果吻合较好,证明了本文建立的模型能较好地模拟再生混凝土试件的宏观力学行为。此外,数值结果表明:端部摩擦会显著影响再生混凝土的峰值强度和破坏模式,并且随着高宽比减小,影响程度增大;端部摩擦的影响范围有限,距离端部越远,受到的影响越小。In this paper, a two-dimensional random aggregate mesoscopic model of recycled concrete is de-veloped using the base force element method, which employs Delaunay triangular dissection aligned with the interface, and the constitutive relation of multi-line damage evolution is used for each phase material in the model, and the Kupfer criterion is applied as the basis for determining damage in the biaxial compression zone. The friction between the recycled concrete specimens and the loading plate was considered using the zero-thickness interface element, and the influence of end friction on the peak strength and failure mode of the recycled concrete specimen was discussed. The numerical results are compared well with experimental results. It is proven that the model established in this paper can simulate the macroscopic mechanical behavior of recycled concrete specimens. In addition, the numerical results show that: End friction significantly affects the peak strength and damage mode of recycled concrete, and the degree of influence increases as the aspect ratio decreases;the influence range of end friction is limited, and the farther away from the end, the smaller the influence is.

关 键 词：再生混凝土 混凝土试件 端部摩擦效应 随机骨料 高宽比 界面单元 细观模型 强度破坏准则 

分 类 号：TU5[建筑科学—建筑技术科学]