Chicago TARP Project Perini-ICA-O&G J.V.
Agitors and Mobile Maxcrete Solve Chicago Tunnel Building Challenge
The original design of this project called for approximately 5 miles of 32′ 4” bore (30’ 4” finished) tunnel and a 4-mile – 24′ bore extension. Unfortunately, this tunnel design consisted of many turns, making it difficult for the Tunnel Boring Machine (TBM) to mine, resulting in lost time/delays due to TBM repairs. To expedite the project, the Joint Venture (J.V.) requested/was granted a change order to bore the complete 9 miles of tunnel at 32′ 4”, thus eliminating any time needed for a change out of the TBM or the concrete lining system.