New QUIKRETE® Wet Shotcrete process wins award
The American Shotcrete Association recognizes Oregon Tunnel Project
By Chad Corley
The QUIKRETE® Companies latest innovation, QUIKRETE® Wet Process Shotcrete, was recently recognized as a critical element in the award-winning Oregon Department of Transportation (ODOT) U.S. Highway 26 Dennis L. Edwards Tunnel Project in Portland, Ore. More than 1,200 bags of 3,000-pound QUIKRETE® Shotcrete MS – Steel Fiber Reinforced was used in the tunnel renovation, which was named 2011 “Outstanding Repair & Rehabilitation Project” by the American Shotcrete Association (ASA).
After 70 years of continuous vehicle traffic between Portland and the Oregon coast on Highway 26, the 772-foot Dennis Edward Tunnel was in need of significant structural restoration. However, renovating the tunnel could not interfere with the daily commute of thousands and had to be complete before traffic doubled when the tourist season began in May 2011. To make the project even more challenging, general contractor, Johnson Western Gunite Company faced wet weather and unstable ground conditions when the project started in Jan. 2011. This made the use of a traditional rock bolt and shotcrete application system impossible, so an extremely unique approach was taken to restore the tunnel. QUIKRETE® Shotcrete MS – Steel Fiber Reinforced was applied up to 18-inches thick between existing timber sets so lagging could be removed and reinforcement applied a section at a time. This process enabled construction to be performed safely and efficiently throughout the night.
In addition to exceeding project strength specifications by reaching 3,800 PSI at one day and more than 9,400 PSI at 15 days, the QUIKRETE® Wet Process Shotcrete limited dust in the application process by batching the shotcrete wet in advance rather the combining the water and shotcrete during the shooting process. As a result, there was little clean-up each morning in preparation for traffic and Johnson Western Gunite Company completed the project on time.
“A combination of factors including the project schedule and traffic considerations really made this a uniquely challenging renovation,” said Don Dodroe, Regional Sales Manager for The QUIKRETE® Companies. “However, with the wet mix process, the Johnson Western Gunite team experienced nearly no rebound and was able to methodically rehabilitate the tunnel in a timely manner without creating any traffic disruptions. This award from the Shotcrete Association really validates that the right approach was taken to restoring the tunnel.”
The QUIKRETE® Companies offers a full line of shotcrete products that can be applied through a wet or dry process to deliver high strength, high adhesion, low rebound and low sag in rehabilitating bridges, tunnels, parking garages, ramps, piers, dams and other concrete structures. In the past decade, QUIKRETE® shotcrete has been used on variety of renovation projects ranging from the Stanford Linear Accelerator in California and the New World Symphony in Florida to the Ashton Hydro Electric Plant in Idaho and Rankin Bridge in North Carolina.
About the Author
Chad Corley is the Director of Public Relations at QUIKRETE.