交变温度对细骨料珊瑚混凝土中钢筋耐腐蚀性能的影响  

Effect of Alternating Temperature on Corrosion Resistance of Reinforcements in Fine Coral Aggregate Concrete

作　　者：冯兴国[1] 范琦琦 杨洋[1] 路新伟 卢向雨 FENG Xingguo;FAN Qiqi;YANG Yang;LU Xinwei;LU Xiangyu(Jiangsu Key Laboratory of Coast Ocean Resources Development and Environment Security,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学江苏省海岸海洋资源开发与环境安全重点实验室,江苏南京210098

出　　处：《建筑材料学报》2022年第5期525-531,共7页Journal of Building Materials

基　　金：南通市科技计划项目(JC2021048,JC2021049)。

摘　　要：为模拟热带海洋环境中温度突变对细骨料珊瑚混凝土结构耐久性的影响,研究了20~70℃交变温度条件下细骨料珊瑚混凝土性能及3种钢筋腐蚀特征的演变,并将其与恒温20、70℃的试样进行对比.结果表明:20~70℃交变温度条件下试样的表观密度与恒温条件下相差不大,但其孔隙率比恒温条件下增加了6%;温度交变下细骨料珊瑚混凝土中钢筋的开路电位(OCP)、腐蚀电流密度(i_(corr))、钢筋/混凝土界面极化电阻(R_(ct))均介于恒定高温和恒定低温试样之间,且更接近恒定低温试样.因此,可推断交变温度会显著加剧细骨料珊瑚混凝土的劣化,但在混凝土保护层防护下,其对钢筋/混凝土界面的劣化作用显著下降.For simulating the effect of alternating temperature,which is caused by the weather variations,on the durability of fine coral concrete,mechanical properties of fine coral aggregate concrete and corrosion behavior of its reinforcement under 20-70 ℃ alternating temperature cycles were studied,and the counterparts at constant 20,70 ℃also were investigated for comparison.The results show that their density values don’t show significant difference when the coral concrete samples experience various temperature conditions.However,the porosity of the fine coral aggregate concrete under 20-70 ℃ alternating temperature conditions is about 6% higher than the ones under the constant temperature solutions.Simultaneously,the open circuit potential(OCP),corrosion current density(i_(corr)),and polarization resistance of the reinforcement/concrete interface(R_(ct))of the reinforcement under alternating temperature cycles are much lower than their counterparts at the higher temperature of the thermal cycle,while the aforementioned parameters of samples under the former conditions are close to the ones at the constant lower temperature of the cycle.Consequently,it can be concluded that the alternating temperature obviously degrades the coral concrete layer,while its degradation effects on the reinforcement/concrete interface are dramatically declined by the concrete cover layer.

关 键 词：温度交变 细骨料珊瑚混凝土 不锈钢钢筋 开路电位 线性极化 交流阻抗 

分 类 号：TU511.3[建筑科学—建筑技术科学]