78 / 2022-04-14 20:51:22

Mechanical performance of concrete structure component after Electrochemical Rehabilitation

Reinforced concrete structure; electrochemical repair; low-cycle reciprocating loading; bond slip; seismic performance; time effect

The electrochemical repair technology drives the harmful substances in the protective layer of concrete structures through the action of an electric field to improve durability. Unreasonable electrochemical repair parameters have adverse effects on material properties, such as reducing the strength of the bond between steel and concrete, increasing the hydrogen embrittlement of steel, declining plasticity, changing the pore structure of concrete, and varying the strength of concrete. The degradation of material performance will further affect the static, fatigue, and seismic performance of the components of structures. To study the influence of the degradation caused by electrochemical repair on the mechanical performance of structures, reinforced concrete beams and columns were set up at different current densities for electrochemical hydrogen charging. Considering the time effect, components was distinguished into EHC components with static standing and EHC components without static standing. The static loading and low-cycle reciprocating test determined the failure mode, crack characteristics, hysteresis curves, skeleton curve, stiffness degradation curves, and ductility performance of the reinforced concrete components. The experimental results show that the crack characteristics of the components remarkably differ based on the influence of the strength of concrete and bond-slip performance degradation of the reinforced concrete; however, the differences disappear with increasing the static standing time. The failure mode, bearing capacity, and energy dissipation capacity of the components do not change significantly under the different parameters used herein. The test results are discussed, and the degradation and recovery mechanism for the structural performance of reinforced concrete component undergoing electrochemical repair are expounded. The research conclusions provide a scientific basis for applying electrochemical repair technology.