【摘要】 对腐蚀的发生机理和影响因素进行了概括,介绍了基于宏腐蚀原理开发的阳极梯系统的工作原理和评价体系;鉴于阳极梯系统难以捕捉到腐蚀发生时的微电流,运用法拉第第二定律计算钢筋锈蚀质量损失存在较大误差,因此采用干湿循环交替试验修正了混凝土开裂后锈蚀质量损失与宏电流的函数关系;根据苏通大桥索塔锚固区的实测数据,简要评估了当前索塔塔壁混凝土碳化程度和钢筋的腐蚀状态。结果表明:索塔锚固区混凝土不同深度的电位及电阻率变化较为稳定,腐蚀宏电流曲线相对平稳,宏电流极值远小于耦合电流的临界值15μA,锚固区混凝土的碳化速度缓慢,钢筋尚未发生腐蚀。研究结果可为相关桥梁结构腐蚀监测提供一定的参考。更多还原

【Abstract】 The corrosion mechanism and the influence factors were summarized,and the working principle of anode-ladder system,which was developed based on the macro corrosion,was introduced in details.The anode-ladder system could hardly catch the micro current,which resulted in large errors when the Faraday’s Second Law was used,to calculate the mass loss caused by corrosion of steel bar.The functional relation between macro current and the mass loss was fixed through wet-dry cycling experiment.According to the measured data in anchorage zone for Sutong Bridge,the current carbonization degree of concrete and the corrosion state of steel bar in cable tower could be assessed.The results show that the cable tower anchorage zone concrete potential and resistivity change in different depths is relatively stable,macro corrosion current curve is relatively smooth,macro current extremum is far less than the critical value of the coupling current about 15 μA,the rate of concrete carbonization is relatively slow in anchorage zone,and the corrosion of steel bar has not occurred.The research can provide some references for the corrosion monitoring in correlation bridge structures.更多还原