锈蚀钢筋与TRC约束混凝土黏结滑移本构关系

尹世平 董朋杰 胡长顺 史振宇

摘   要：采用试验和理论分析相结合的方法，基于电化学锈蚀中心拉拔试验，研究在有无纤维编織网增强混凝土（TRC）约束下，对不同电化学锈蚀率变形钢筋与混凝土界面黏结性能的影响，并且对试件破坏形态以及黏结滑移曲线等进行了分析研究. 研究结果表明：在无TRC约束的情况下，锈蚀钢筋与混凝土极限黏结应力随锈蚀率增加而降低，尤其是混凝土产生锈胀裂缝后极限黏结应力下降明显;TRC约束对锈蚀钢筋与混凝土的黏结性能尤其是锈蚀程度较大的试件有很好的改善作用;对于产生锈胀裂缝的试件，TRC约束具有良好的限制试件开裂以及提高极限黏结应力的作用，同时TRC约束对维持锈蚀钢筋与混凝土的黏结刚度也有明显效果;最后建立了TRC约束混凝土与锈蚀钢筋上升段的黏结滑移本构关系.

关键词：TRC约束混凝土;黏结滑移;本构关系;锈蚀;加固

中图分类号：TU375                             文献标志码：A

文章编号：1674—2974（2021）01—0144—10

Abstract：In this paper， the combination of experimental and theoretical analysis was used to study the effect of Textile Reinforced Concrete （TRC） confinement on the bond behavior between the deformed steel bars and concrete with different corrosion ratios through the pull-out experiment at electrochemical corrosion center. The experimental results showed that，without TRC confinement， the bond strength decreased with the increase of the corrosion ratio， especially after the rust crack was obvious. The TRC confinement had a good effect on the bond performance between the rust bar and the concrete， especially when the degree of corrosion was large. For the specimens with rust cracks， TRC confinement had a good effect on limiting cracking and increasing ultimate bond stress， and also had a significant effect on maintaining the bond stiffness. Finally， the rising section of the bond-slip constitutive relationship between the TRC-confined concrete and the corroded steel bar was established.

Key words：TRC-confined concrete;bond slip;constitutive relationship;corrosion;reinforcement

钢筋混凝土材料由于其相对低廉的价格、成熟的施工工艺以及设计理念，已经成为土木工程领域应用最为广泛的建筑材料. 钢筋与混凝土界面良好的黏结性能是钢筋混凝土结构正常工作的前提，而在结构使用中不可避免地会发生钢筋锈蚀，这使得钢筋与混凝土黏结作用受到影响，降低了结构的性能和可靠性，从而缩短结构的服役期限[1].

为了提高锈蚀钢筋与混凝土界面的黏结性能，进行结构加固是一种行……