海洋环境中氯离子和硫酸根离子交互作用下钢筋混凝土结构力学性能劣化研究

The diffusion behavior of chloride ions and sulfate ions in concrete, as well as the deterioration of the corrosion behavior of corroded reinforced-concrete interface are the key scientific problems for the deterioration of mechanical properties of reinforced concrete structures in marine environment. The present project focuses on the interaction between chloride ions and sulfate ions. On the basis of the diffusion test of these two kinds of ions in concrete, the two diffusion models describing the evolution of micro characteristics of concrete are established. Combined the bonding test of corroded reinforcement-concrete interface and the microscopic analysis of corrosion zone, the corresponding interface debonding model is established. With the aid of selected constitutive relations of sulfate corroded concrete and chloride corroded reinforcement, the calculation module is compiled for simulating the performance degradation of reinforcement concrete structure. Further, the mechanical properties of the reinforcement concrete members under the interaction of sulfate ions and chloride ions are experimentally studied, and the rationality analysis of the module is carried out. The achievement of this project will contribute to understanding the degradation mechanism of reinforced concrete structures under marine environment, to evaluating efficiently the mechanical properties, and to predicting the service life of reinforcement concrete structures in the off-shore engineering.

氯离子、硫酸根离子在混凝土内的扩散行为，以及锈蚀钢筋-混凝土界面粘结性能退化是海洋环境中钢筋混凝土结构力学性能劣化的核心科学问题。本项目重点考虑两种离子的交互作用效应，基于试验开展混凝土内氯离子、硫酸根离子扩散系数研究，建立描述混凝土微观特征演化的离子扩散模型；通过锈蚀钢筋-混凝土粘结性能试验和腐蚀区微观特性研究，建立描述界面微观特征的锈蚀钢筋-混凝土界面粘结模型；整合已有的硫酸盐腐蚀混凝土本构模型和锈蚀钢筋力学模型，编制腐蚀钢筋混凝土结构力学性能计算模块；结合氯离子和硫酸根离子交互作用下的钢筋混凝土构件力学试验，开展模型验证和腐蚀构件性能分析，加深对海洋环境中钢筋混凝土结构劣化机制的理解，为近海工程钢筋混凝土结构力学性能评估和寿命预测提供计算手段。

硫酸根离子、氯离子在混凝土内的扩散行为，以及锈蚀钢筋-混凝土界面粘结性能退化是海洋环境中钢筋混凝土结构力学性能劣化的核心科学问题。本项目通过不同侵蚀环境下硫酸根离子和氯离子的扩散行为试验研究，建立了描述硫酸根离子和氯离子交互作用的受腐蚀混凝土离子扩散模型；通过不同锈蚀程度下钢筋混凝土开裂行为和粘结滑移特性试验研究，建立了锈胀开裂前后钢筋混凝土粘结强度模型；在此基础上，建立了综合考虑硫酸盐腐蚀混凝土和氯盐锈蚀钢筋的受腐蚀钢筋混凝土损伤模型，并结合钢筋混凝土构件力学试验进行了模型验证。项目成果加深了对海洋环境中钢筋混凝土结构劣化机制的理解，为近海工程钢筋混凝土结构力学性能评估和寿命预测提供了计算手段。