钢筋与混凝土的时变性能研究进展

RESEARCH PROGRESS ON TIME-VARYING PERFORMANCE OF REINFORCED CONCRETE

作为混凝土结构中的受力材料,钢筋和混凝土的力学性能变化将直接影响结构构件的安全性。主要从钢筋混凝土结构的材料层次、环境层次和构件层次出发,对混凝土强度时变性、钢筋性能时变性及锈蚀钢筋与混凝土粘结性能变化的现有研究成果进行综述。首先,阐述了混凝土时变性能研究的分析方法,包括考虑单一影响因素的混凝土碳化、氯盐侵蚀、冻融循环作用以及考虑多因素耦合作用条件下混凝土性能的经时变化;其次,基于国内外大量研究成果,归纳总结了在一般大气环境下,由钢筋锈蚀引起的混凝土锈胀裂缝在开裂前和开裂后的钢筋性能变化;最后,综合分析现阶段研究,为今后既有结构混凝土和钢筋的性能变化研究方向提供参考。

As the stress material in concrete structure,the change of mechanical properties of steel bar and concrete will directly affect the safety of structural members.Based on the material level,environmental level and member level of reinforced concrete structure,the existing research results on the time-varying strength of concrete,the time-varying performance of steel bar,and the change of bond properties between corroded steel bar and concrete were summarized.Firstly,the analysis method of time-varying performance of concrete was described,including concrete carbonation,chloride erosion,freeze-thaw cycle,and time-dependent change of concrete performance considering multi-factor coupling.Secondly,based on a large number of research results at home and abroad,the property changes of concrete steel bars before and after cracking caused by steel corrosion in general atmospheric environment were summarized.Lastly,the comprehensive analysis of the present research provided a reference for the future research direction of the performance change of the existing structural concrete and steel bar.