LAKEVIEW — The Chicago Transit Authority’s new Red-Purple Bypass has been repaired after chunks of concrete started falling from the structure last year.
The missing sections of concrete, which left steel rebar and PVC drainage pipes exposed, was spotted last year by locals who questioned the safety of the structure just months after it started service.
CTA officials said at the time the damage to the concrete structure supporting the flyover was only cosmetic and caused by “spalling,” a condition in which concrete fragments break off off their larger body. It happened when water got into parts of the bypass’s PVC drainage sleeves and froze, putting pressure on the surrounding material that broke it off.
CTA spokesperson Tammy Chase said it was a “quality issue” related to work performed by Walsh-Fluor, the contractor that built the bypass. Until its repair, Walsh-Fluor performed daily inspections of the bypass to remove any loose concrete before it had a chance to fall.
Stephanie Cavazos, another CTA spokesperson, told Block Club Tuesday that work to repair the spalling damage was finished in December.
“The workers performed ‘form work,’ using lumber to create the shape of the area on the bypass exterior that needed to be filled with concrete material — similar to how a new sidewalk is poured and cured,” Cavazos said. “Each anchor rod, the metal elements that connect the concrete to the steel in the new bridge, was successfully removed and regrouted at the time of completion.”
The repairs were done entirely at the expense of Walsh-Fluor, Cavazos said.
The Red-Purple Bypass is part of the CTA’s $2.1 billion Red and Purple Modernization project, which is in Phase 1. The flyover began service in November 2021 to allow Brown Line trains to more efficiently pass the Red and Purple line tracks in Lakeview.
The bypass eliminates a 114-year-old rail junction between the Red, Purple and Brown line trains just north of Belmont Avenue that had become a chokepoint for rail service, according to the CTA.
The bypass improves service on the three train lines by allowing the Brown line trains to pass over the Red and Purple line tracks, rather than crossing in front of the them, according to the CTA. Previously, trains on the three lines regularly had to stop and wait for each other to cross the junction.
Phase 1 of the Red and Purple Modernization project includes three major components, including the Red-Purple Bypass, which began work in October 2019.
The project includes reconstructing the Red Line’s Lawrence, Argyle, Berwyn and Bryn Mawr stations so they are larger and 100 percent accessible, according to the CTA. That work already began and should be finished by the end of 2024.
For the last major component of Phase 1, the CTA will install a new signal system on 23 miles of track between the Howard and Belmont stops, which will improve train flow and service reliability, according to the CTA.
More information on the Red and Purple Modernization project can be found on the CTA’s website.
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