Influence Of Corrosion On The Bond Performance Between Rebar And Concrete

As for reinforced concrete structures, member performance can be normally exerted with full use of bar strength due to good bond between reinforcement and concrete under regular design, construction and service conditions. However, abominable environment can induce reinforcement corrosion in concrete, which will further lead to a series of durability problems. Corrosion induced deterioration of bond between rebar and concrete has great influence on the bearing capacity, ductility and failure mode of structures. Hence, research on the influence of corrosion on the bond performance between rebar and concrete has important significance on both bond theory and durability problems.Current researches are mostly conducted with small members, and results of them have not been unified yet. Meanwhile, there are fewer experiments focused on larger reinforced concrete members, especially columns with certain eccentricity. As a result, there is not certain evidence to certify whether conclusions of small members are available for larger one and whether the results of pull-out or beam test are as the same as that of columns. Aiming at these shortages, short hooped reinforced concrete columns with certain eccentricity were adopted to study the bond performance between corroded rebar and concrete at the layer of large member here. The accelerated corrosion method with current was used simultaneously.In this paper, test values of bond strength in compression-bending columns were gained. Compared with calculated values obtained through theoretical way, correlation between them was analyzed. By comparison between other research results and conclusions here, understanding of bond durability at lower corrosion layer (5%) was unified, which will expand the application range of former researches. Besides, the bond anchorage capacity of compression-bending members can be calculated according to known bond strengthτu using formula presented in this paper.Research achievements concerning the durability of bond between reinforcement and concrete in this paper give us to understand the bond regularity more roundly. Reference for future research in this field and instructions for engineering practice are also provided.