Structural Repair of Cross-Passage 5, Interstate 70 Hanging Lakes Tunnel

摘要

The twin bore Hanging Lake Tunnels (HLT) in Colorado on Interstate 70 (I‑70) are operated byrnthe Colorado Department of Transportation (CDOT). The tunnels include eight (8) cross-passages that housernsensitive equipment and provide emergency egress. Structural integrity inspections were conducted in 2009.rnCracked shotcrete was observed in Cross-Passage 5 (CP‑5).rnAreas in CP‑5 had substantial de-lamination of the shotcrete. A ground characterization plan was accomplishedrnbased on exploratory drilling and testing. An innovative repair was developed including Polyurethanern(PUR) injection, and installation of tensioned rock bolts. The repair was successfully completed in late 2010rnand monitoring of the cross-passage is ongoing.