Lun Pei-Yuan, Zhang Xiao-Gang, Jiang Ce, Ma Yi-Fei, Fu Lei
Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, China.
School of Civil Engineering, Central South University, Changsha 410000, China.
Materials (Basel). 2021 Mar 16;14(6):1440. doi: 10.3390/ma14061440.
The premature failure of reinforced concrete (RC) structures is significantly affected by chloride-induced corrosion of reinforcing steel. Although researchers have achieved many outstanding results in the structural capacity of RC structures in the past few decades, the topic of service life has gradually attracted researchers' attention. In this work, based on the stress intensity, two models are developed to predict the threshold expansive pressure, corrosion rate and cover cracking time of the corrosion-induced cracking process for RC structures. Specifically, in the proposed models, both the influence of initial defects and modified corrosion current density are taken into account. The results given by these models are in a good agreement with practical experience and laboratory studies, and the influence of each parameter on cover cracking is analyzed. In addition, considering the uncertainty existing in the deterioration process of RC structures, a methodology based on the third-moment method in regard to the stochastic process is proposed, which is able to evaluate the cracking risk of RC structures quantitatively and predict their service life. This method provides a good means to solve relevant problems and can prolong the service life of concrete infrastructures subjected to corrosion by applying timely inspection and repairs.
钢筋混凝土（RC）结构的过早失效受到钢筋氯化物诱导腐蚀的显著影响。尽管在过去几十年里，研究人员在RC结构的结构能力方面取得了许多出色成果，但使用寿命这一主题已逐渐引起研究人员的关注。在这项工作中，基于应力强度，开发了两个模型来预测RC结构腐蚀诱导开裂过程的临界膨胀压力、腐蚀速率和保护层开裂时间。具体而言，在所提出的模型中，既考虑了初始缺陷的影响，又考虑了修正后的腐蚀电流密度。这些模型给出的结果与实际经验和实验室研究结果吻合良好，并分析了各参数对保护层开裂的影响。此外，考虑到RC结构劣化过程中存在的不确定性，提出了一种基于随机过程三阶矩法的方法，该方法能够定量评估RC结构的开裂风险并预测其使用寿命。该方法为解决相关问题提供了一种良好手段，通过及时检查和修复，可以延长遭受腐蚀的混凝土基础设施的使用寿命。
