Abstract

This paper presents a case study of corrosion damage of a concrete chimney sited in a steel production plant in front of the Mediterranean Sea. The aggressive environment to which the chimney is exposed and its limited accessibility make the assessment of its condition critical. Destructive and non-destructive tests have been carried out over time to evaluate possible deterioration phenomena of concrete and corrosion of the reinforcement. The available documentation both on the construction and on previous repair interventions, besides the results of several investigations are discussed in the paper with the aim of assessing the chimney and proposing guidelines for the design of a durable and effective repair intervention, in relation with reinforcement corrosion. Results show that it is not possible to identify a single cause of damage, but rather a synergistic effect of corrosion of steel reinforcement due to chlorides ingress and carbonation and a moderate chemical attack of concrete due to exposure to fumes of the plant. Moreover, although the chimney was repaired several times, such interventions, not properly realized, promoted corrosion rather than control it.

摘要

本文介绍了位于地中海前的一家钢铁生产厂的混凝土烟囱腐蚀损坏的案例研究。烟囱所处的恶劣环境及其有限的可达性使得对其状况的评估变得至关重要。随着时间的推移，已经进行了破坏性和非破坏性试验，以评估混凝土可能的劣化现象和钢筋的腐蚀。除了几项调查的结果外，本文还讨论了有关施工和先前维修干预措施的可用文件，目的是评估烟囱并提出与钢筋腐蚀相关的持久有效维修干预措施的设计指南. 结果表明，不可能确定单一的损坏原因，而是由于氯化物进入和碳化引起的钢筋腐蚀的协同效应，以及由于暴露于工厂烟雾而导致的混凝土中度化学侵蚀。此外，虽然烟囱被修复了几次，但这种干预措施没有得到正确的认识，反而促进了腐蚀而不是控制腐蚀。