RepairUndergroundStructuralCSX Pinkerton Tunnel
Dennis Bittner, Nick Laviolette, and Denis Laviolette
Read MoreAs part of the National Gateway Clearance Project, the Pinkerton Tunnel, located in Markleton, PA, was to be removed because it did not have the required height clearance to accommodate double-stack freight railroad cars.
RepairUndergroundStructuralWhere Are We Now with Sprayed Concrete Lining in Tunnels?
Andrew Pickett and Dr. Alun Thomas
Read MoreTraditional methods of sprayed concrete lining (SCL) tunnels (in soft ground) comprise a temporary primary lining of sprayed concrete with a sheet membrane inside and a permanent cast in-situ concrete lining, usually reinforced with steel bars
UndergroundStructuralReaching 20 MPa (2900 psi) in 2 Hours is Possible
Simon Reny and William Clements
Read MoreIn the mining and tunneling industries, time is critical; and as the mining/tunneling cycle becomes shorter, production increases.
UndergroundStructuralGeneralSustainable Shotcrete Using Blast-Furnace Slag
Philip Sawoszczuk, Dr. Michelle Nokken, and Dr. Marc Jolin
Read MoreTwo shotcrete mixtures were designed based on sustainability for use in mining ground support.
UndergroundAbility to Access Restricted Space and Difficult-to-Reach Areas, Including Overhead and Underground
Top 10 Sustainability #10
Read MoreAccessing the site of a concrete pour can often be one of the biggest challenges faced by contractors.
RepairUndergroundStructuralFort McHenry Tunnel Miscellaneous Structural Repairs
John Becker
Read MoreAt the time of its construction, the widest underwater tunnel in the world, the Fort McHenry Tunnel in Baltimore, MD, was opened to traffic in 1985.
UndergroundRapid-Setting Cement in Shotcrete
Mike Ballou
Read MoreEvolving technology in the shotcrete industry using a rapid-setting mixture with calcium sulfoaluminate (CSA) cement in lieu of a more common portland cement mixture is helping to meet the challenges for shotcrete repairs and underground projects throughout the world.
RepairUndergroundStructuralSoudan Mine Shaft Rehabilitation
Shane McFadden
Read MoreThe Soudan Mine is a historic taconite and iron ore mine in Northeastern Minnesota.
RepairUndergroundStructuralShotcrete Work in Confined Space Area
Ted W. Sofis
Read MoreShotcrete work, by its very nature, provides an excellent method of installing concrete materials in storage bins, hoppers, culverts, inlets, vaults, tanks, and other areas, where it is difficult to transport and efficiently install materials by conventional casting methods.
RepairUndergroundStructuralUnderground Shotcrete Roof Repair of Hanging Lake Tunnel
Warren Harrison
Read MoreDuring a Federal Highway Administration annual safety inspection in March 2007, a crack was found in the flat roof portion of the cut and cover section of the Hanging Lake Tunnels along Interstate 70 in Glenwood Springs, CO.