组合结构中栓钉腐蚀的半电池电位检测

CORROSION DETECTION OF STUDS IN STEEL-CONCRETE COMPOSITE STRUCTURES BY HALF-CELL POTENTIAL TEST

对力学试验后,在大气中自然暴露7年的钢-混凝土组合结构中的栓钉腐蚀情况,用半电池电位法进行检测,结合破损检查,探讨了ASTM C876标准的适用性。试验研究了测点间距、混凝土表面润湿程度、混凝土保护层厚度及上层钢筋网对栓钉电位检测值的影响。试验结果表明:当混凝土表面充分润湿时,测点间距对栓钉电位检测值基本无影响;混凝土表面润湿程度和混凝土保护层厚度会显著影响栓钉电位的测量值;上层钢筋网的影响尚待进一步研究。经无损和破损试验结果对比后认为,ASTM C876方法仍可用于组合结构中栓钉腐蚀可能性的判定。

Half-cell potential method was employed to detect the corrosion of studs in steel-concrete composite structures after natural exposure in air for 7 years, which had experienced mechanical test. It was explored the applicability of ASTM C876 based on destructive test . The influence of the electrode distance, the wetness degree of concrete surface, the thickness of concrete cover and the rebar mat on the. electrochemical potential of studs was preliminarily studied. The results showed that the electrode distance did not affect the stud potential when the concrete surface fully wetted. However, the wetness degree and the thickness of concrete cover had a remarkable effect on the studs＇ potential. The influence of rebar mat needs further study. Based on the results obtained by non- destructive and destructive tests, it is concluded that the ASTM C876 method is still applicable to judge the corrosion state of studs in the composite structures.