氯离子在混凝土桩基中扩散过程的有限元分析

Finite Element Analysis of Chloride Ion Diffusion Process in Concrete Pile Foundation

文中考虑扩散时间、环境温度以及湿度因素,建立了改进的氯离子扩散模型,并通过模型计算对比混凝土中氯离子质量分数试验值和模拟值,验证了该方法对于氯离子在混凝土扩散模拟的准确性;运用该方法,对海洋环境中科特迪瓦阿比让四桥桩基氯离子扩散过程进行模拟.结果表明:桩基中钢筋对氯离子扩散存在影响,在考虑有无钢筋存在情况下,桩基内部同一深度位置的氯离子质量分数值最大差值为19.8%;并预测了科特迪瓦阿比让四桥桩基的耐久性寿命,考虑钢筋存在时的耐久性寿命比不考虑钢筋存在时的耐久性寿命缩短了4.8%.

Considering the factors of diffusion time,ambient temperature and humidity,an improved chloride ion diffusion model was established.Through the model calculation,the experimental value and simulation value of chloride ion concentration in concrete were compared,and the accuracy of this method for chloride ion diffusion simulation in concrete was verified.Using this method,the chloride ion diffusion process of the pile foundation of the Fourth Bridge in Abidjan,Cote d’Ivoire was simulated in the marine environment.The results show that reinforcement in pile foundation has influence on chloride ion diffusion,and the maximum difference of chloride ion concentration at the same depth in pile foundation is 19.8%considering whether reinforcement exists or not.The durability life of the pile foundation of the fourth bridge in Abidjan,Cote d’Ivoire is predicted,and the durability life with steel bars is 4.8%shorter than that without steel bars.