钢筋混凝土结构物抗盐冻性能的影响因素与寿命预测

对钢筋混凝土结构物抗盐冻性能的影响因素进行了研究,并对其使用寿命进行了预测.结果表明,硫酸盐能使混凝土中氯离子侵蚀浓度降低,在侵蚀早期比较明显,在晚期表现不显著.在钢筋混凝土结构进入到了冻融循环的时候开始,保持二者的龄期基本趋向一致,就会发现这两种混凝土材料中的耐腐蚀混凝土材料中所收到的侵蚀远比普通混凝土材料的严重,尤其体现在质量的变化上.温度对混凝土氯离子扩散速度具有显著影响,氯离子扩散速率随温度降低而变慢.临界氯离子浓度提高、混凝土保护层厚度增加、氯离子结合系数增大都能延长结构耐久性寿命;结构材质的耐久性寿命对于多个参数的影响程度很是敏感,例如氯离子的扩散系数、钢筋混凝土的保护层层厚度、其最原始的氯离子浓度、临界值氯离子浓度等,发现其表面的氯离子浓度的敏感程度比较低。

Influencing factors and life prediction of salt and frost resistance of reinforced concrete structures

The influencing factors of salt-frost resistance of reinforced concrete structures are studied,and their service life is predicted.The results show that sulfate can reduce the chloride ion corrosion concentration in concrete,which is more obvious in the early stage of corrosion,but not significant in the late stage.When the age of freeze-thaw cycles is the same,the quality loss of corrosion-resistant concrete is greater than that of ordinary concrete.Temperature has a significant effect on the diffusion rate of chloride ions in concrete.The lower the temperature,the slower the diffusion rate of chloride ions.The durability life of the structure can be prolonged by increasing the critical chloride ion concentration,the thickness of the concrete protective layer and the chloride ion binding coefficient.The durability life of the structure is sensitive to the chloride ion diffusion coefficient,the thickness of the concrete protective layer,the initial chloride ion concentration and the critical chloride ion concentration,and is sensitive to the surface chloride ion concentration.The degree of perception is low.