RailWorks improved track quality and safety by replacing 38,000 wood half-ties with direct-fixation fasteners cast in concrete.
The $2.7 million effort was performed in a tunnel on the 22-mile Red Line. The line is the busiest of eight routes comprising Chicago's rapid transit system, known as the "L." RailWorks crews coordinated their work among up to 100 laborers, operating engineers, concrete finishers, electricians and others.
Special hi-rail demolition and concrete delivery equipment was modified for use in tight spaces within the tunnel. Wet conditions are prevalent in the tunnel, and to avoid the maintenance involved with wood-tie track construction, direct-fixation fasteners were used. The fasteners, cast into concrete, withstand the weather and rail wear over time. They also can be adjusted continually to maintain the proper gauge.