Shao Wei, He Xiaoqing, Shi Danda, Zhu Wenjin
College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai 201306, China.
Department of Hydraulic Engineering, School of Civil Engineering, Tongji University, Shanghai 200092, China.
Materials (Basel). 2023 Sep 26;16(19):6403. doi: 10.3390/ma16196403.
A novel prediction model for crack development of reinforced concrete (RC) piles with localized chloride corrosion in the marine environment is proposed. A discrete method is used to solve the corrosion pit radius model and a crack extension model is developed to investigate the initiation and extension of cracks. The maximum corrosion degree of the reinforced concrete pile is predicted according to the limit crack criterion, and finally, a sensitivity analysis is carried out on the important parameters of crack extension. The results show that the radius of the corrosion pit, the depth corrosion pit, and the cross-sectional area loss of reinforcement gradually increase as the corrosion level increases. The loss of the local reinforcement section at crack initiation increases with the increase in the ratio of concrete cover to initial diameter and increases with the increase in the pitting factor. The required pit depth for reinforcement cracking increases with the increase in the ratio of concrete cover thickness to diameter. The loss of the cross-sectional area of reinforcement and the radius of the corrosion pit increase with the increase in the initial diameter of reinforcement. Increasing the pitting factor can reduce the pit depth and make the crack width develop faster before reaching the limit crack width. Increasing the concrete cover thickness can provide an improvement in the propagation of cracks. A comparative analysis shows that the localized corrosion pattern is more in conformity with marine engineering practice.
提出了一种针对海洋环境中局部氯化物腐蚀的钢筋混凝土（RC）桩裂缝发展的新型预测模型。采用离散方法求解腐蚀坑半径模型，并建立裂缝扩展模型以研究裂缝的萌生与扩展。根据极限裂缝准则预测钢筋混凝土桩的最大腐蚀程度，最后对裂缝扩展的重要参数进行敏感性分析。结果表明，随着腐蚀程度的增加，腐蚀坑半径、腐蚀坑深度和钢筋截面积损失逐渐增大。裂缝萌生时局部钢筋截面损失随混凝土保护层厚度与初始直径之比的增加而增大，且随点蚀系数的增加而增大。钢筋开裂所需的坑深随混凝土保护层厚度与直径之比的增加而增大。钢筋截面积损失和腐蚀坑半径随钢筋初始直径的增加而增大。增加点蚀系数可减小坑深，并使裂缝宽度在达到极限裂缝宽度之前发展得更快。增加混凝土保护层厚度可改善裂缝的扩展。对比分析表明，局部腐蚀模式更符合海洋工程实际。
