锈蚀对钢筋强度影响试验研究

通过从实桥构件和电化学快速锈蚀构件中获得361根锈蚀钢筋样本,基于锈蚀钢筋拉伸试验,分别建立了HPB235和HRB335两种类型钢筋的质量锈蚀率、截面锈蚀率与屈服荷载、极限抗拉荷载、屈服强度及极限抗拉强度间的关系,对比了锈蚀率对不同类型钢筋屈服强度、极限抗拉强度、屈服荷载和极限抗拉荷载的影响;回归了快速锈蚀与自然锈蚀两种环境下钢筋质量锈蚀率与屈服荷载和极限抗拉荷载的关系,分析了两种环境对锈蚀钢筋力学性能影响的差异。研究表明:锈蚀对极限荷载、极限强度的影响分别大于屈服荷载、屈服强度;锈蚀对HRB335钢筋的影响比对HPB235钢筋的大;快速锈蚀条件下钢筋屈服荷载和极限荷载下降速度较自然锈蚀条件的快。

Experimental Study on Effect of Corrosion on Reinforcement Strength

The tensile test on 362 corroded reinforcements, which obtained from the electrochemical accelerated corrosion members and the field bridge members, was made. For HPB235 and HRB335, the relationships  of quality corrosion rate, cross section corrosion rate with yield load, ultimate tensile load, yield strength and ultimate tensile strength were established respectively based on the test. The effects of corrosion rate on yield strength, ultimate tensile strength, yield load, and ultimate tensile load of different types of reinforcement were analyzed. The regression analysis on the relationships of reinforcement quality corrosion rate with yield load and ultimate tensile load in nature and accelerated corrosion environments were carried out. The influencing difference of the two environments on the mechanical property of corroded reinforcement was analyzed. The experimental results show that (1) the effect of corrosion on the ultimate load and strength is greater than that on yield load and yield strength respectively; (2) the HRB335 is more sensitive for corrosion than HPB235; (3) the degradations of yield load and ultimate load are faster in accelerated corrosion environment than that in nature environment.