通过试验模拟海洋环境下氯离子对在役混凝土柱的侵蚀,探究了干湿交替环境下应力水平及试验周期对氯离子在混凝土中传输特性的影响规律.采用干湿时间比为2∶1的干湿循环制度,试验历时1a,研究了不同应力水平下混凝土内的氯离子含量分布特性.通过数据分析得到应力水平和试验周期对混凝土内氯离子传输进程、表面氯离子含量、对流区深度及峰值氯离子含量的影响规律;建立了同时考虑应力水平和试验周期影响的氯离子扩散系数预测公式;阐释了应力水平对干湿交替环境下混凝土中氯离子不同传输机制的影响机理.
By the test of reinforced concrete columns in simulated marine environment under sustained load, the influence rules of stress level and test period were explored on transport characteristics of chloride ions. Using dry-wet time ratio of 2 : 1, concentration distribution characteristics of chloride ions were studied by the experiment of specimens with different stress levels for one year. The influence rules of stress level and test period were obtained on chloride ion transport process, surface chloride ion concentra- tion, convection zone depth and the peak value of chloride ion concentration by data analysis. Formula was established to predict the chloride ion diffusion coefficient considering both stress level and test period. The influence of stress level was illustrated on the different transmission mechanisms of chloride ion in concrete under dry-wet cycles.