相邻钢筋非均匀锈蚀引发混凝土保护层开裂的细观数值模拟-《建筑科学与工程学报》

文章信息/Info

Title:: Meso-scale Numerical Simulation on Crack Process of Concrete Cover Induced by Adjacent Rebar Nonuniform Corrosion

Author(s):: ZHANG Ren-bo, DU Xiu-li, JIN Liu; Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education

Keywords:: concrete cover; mesoscale numerical simulation; rebar nonuniform corrosion; corrosion mechanism; failure mode

摘要:: 对2根相邻钢筋非均匀锈蚀膨胀引发的混凝土保护层破坏行为进行了细观数值模拟研究；考虑到混凝土细观结构非均质性的影响，将混凝土视为由骨料、砂浆和界面过渡区组成的三相复合材料，以施加强制位移的方式模拟钢筋的非均匀锈胀作用，建立了混凝土保护层开裂分析的细观尺度数值模型，并进行了影响参数分析。结果表明：细观数值模拟结果与已有文献中的试验结果吻合良好；相邻钢筋非均匀锈蚀时会发生内部裂纹相互贯通先于和落后于外部开裂2种破坏模式；钢筋直径不是影响混凝土保护层破坏的主要参数；混凝土保护层厚度主要影响外部开裂的发展；钢筋间距则主要控制内部裂纹的相互贯通。

Abstract:: In order to investigate the crack process of concrete cover induced by two adjacent rebar nonuniform corrosion, a mesoscale numerical model was established. Considering the influence of concrete mesostructure, the concrete was assumed to be a threephase composite material composed of aggregate, mortar matrix and interfacial transition zone (ITZ), and the mechanical effect of rebar nonuniform corrosion was simulated by the forced displacement. A parametric study was conducted based on the model. The results show that the mesoscale simulation results are coincided with the test results from the literature; there are two failure patterns including internal cracking penetration taken place more easily or difficult than external cracking; rebar diameter is not a main parameter influencing the failure of concrete cover; concrete cover thickness effects the development of external cracking principally; and rebar distance controls internal cracking penetration predominantly.