Degradation of bond between steel bar and freeze-thaw concrete after electrochemical chloride extraction

【摘要】 The effect of electrochemical chloride extraction(ECE) on bond strength between steel bar and freeze-thaw concrete contaminated by chloride was experimentally investigated for beam specimens with dimensions of 100 mm×100 mm×400 mm.During the experiment,3% NaCl(vs mass of cement,mass fraction) was mixed into concrete to simulate chloride contamination,and the specimens experienced 0,25,50,75 freeze-thaw cycles before ECE.In the process of ECE,different current densities and durations were adopted.It is indicated that the bond strength between reinforcement and concrete decreases with the increase of freeze-thaw cycles;the more the current and the electric quantity of ECE are,the more the loss of bond strength is;and the largest loss is up to 58.7%.So,it is important to choose proper parameters of ECE for the reinforced concrete structures contaminated by chloride and subjected to freeze-thaw cycles.更多还原

【Abstract】 The effect of electrochemical chloride extraction(ECE) on bond strength between steel bar and freeze-thaw concrete contaminated by chloride was experimentally investigated for beam specimens with dimensions of 100 mm×100 mm×400 mm.During the experiment,3% NaCl(vs mass of cement,mass fraction) was mixed into concrete to simulate chloride contamination,and the specimens experienced 0,25,50,75 freeze-thaw cycles before ECE.In the process of ECE,different current densities and durations were adopted.It is indicated that the bond strength between reinforcement and concrete decreases with the increase of freeze-thaw cycles;the more the current and the electric quantity of ECE are,the more the loss of bond strength is;and the largest loss is up to 58.7%.So,it is important to choose proper parameters of ECE for the reinforced concrete structures contaminated by chloride and subjected to freeze-thaw cycles.更多还原