Burlington Skyway
The Problem
The Burlington Skyway has a total of 75 spans supported by 44 concrete piers and 30 structural steel beams. Some of these structural members were exposed to severe chloride contamination due to deicing salts used for winter maintenance, creating a large corrosion potential within the structure. The ICCP system installed in the late 80s and early 90s was also rendered inadequate in preventing corrosion due to a cementitious overcoat that was used in its cover. Another solution was required to extend the service life of the structure.
Our Solution
The structure was a perfect candidate for the first field trial use of Norcure Electrochemical Chloride Extraction (ECE) in North America. The Ontario Ministry of Transportation funded the field study and built upon the SHRP Contract C-102A findings, which indicated the technique was feasible. The system was installed on the lower 13 ft (4 m) of the west column in July 1989. Only three sides of the square column were treated, leaving the north side to act as a control area.
The Result
Throughout the duration of the treatment, the system was monitored very closely, often daily, to have sound results throughout testing. After treatment was completed, it was found that the percentage of chloride ions removed above reinforcing steel was as high as 87% in some areas. Corrosion potential results showed that six months later, after depolarization, the reinforcement was in a passive and noncorroding state. MTO has continued to monitor the pier since the application of the Norcure System. These long-term results show how ECE’s effectiveness has withstood the test of time.
Technology Used
These innovative products and technologies were used on this project.