IL 120 Over U.S. 41

HNTB provided Phase III construction engineering and inspection services for improvements to IL 120 over U.S. 41, Old Skokie Road, Union Pacific Railroad, Canadian Pacific Railroad ramps, Greenleaf Avenue and U.S. 41 to Knight Avenue. The project consisted of two contracts constructed concurrently, which required close coordination of the maintenance of traffic and construction sequencing. The HNTB team successfully managed both contracts by leveraging proactive strategies.

The project involved the rehabilitation of 10 bridge structures along IL 120 in Waukegan, Park City and Gurnee. Work included deck removal and replacement, and superstructure and substructure rehabilitation. Bridge abutment backwalls were removed and replaced, wing walls repaired, rocker bearings replaced with elastomeric bearings, and diaphragms added to the bridge framing units. Work also included girder cleaning and painting, removing and replacing approach slabs, slope walls, bridge drainage systems, ripraps and other incidental work.

Maintenance of traffic during construction used temporary crossovers, ramps and pavements that were converted into permanent shoulders. Through HNTB innovations, Stages 1 and 2 were accelerated to complete bridge work within the first year. Stage 3 consisted of patching, milling and HMA paving. Both contracts were completed on time.