
The Transportation Expansion Project, also known as T-REX, is a landmark collaborative effort between the Colorado Department of Transportation (CDOT) and Regional Transportation District (RTD), and is shaped by extensive public input from across the metro Denver area. This project is the next step in the evolution of an aging, outdated transportation system to a modern, integrated network of highway and light rail options. It includes highway expansion and safety improvements, the addition of light rail along I-25 and I-225, reconstruction of interchanges and bridges, a new drainage system and improved pedestrian and bicycle access. Loadtest is pleased to be involved in this landmark project with Southeast Corridor Constructors and the Anderson Drilling Co.
Franklin Street/I-25 Overpass
Loadtest’s first O-cell on the T-Rex site was at the new Franklin Street overpass, spanning I-25. Anderson Drilling excavated the production test shaft, socketed in rock. The shaft was constructed with a 42-inch (1066-mm) auger to a total length of 25.3 feet (7.70 meters) from tip of shaft to the concrete cut-off elevation. The test shaft was successfully loaded to a combined side shear and end bearing of more than 5610 kips (25.0 MN).
I-25/I-215 Interchange
Anderson Drilling excavated this 42-inch (1070-mm) diameter dedicated test shaft to a total length of 22.6 feet (6.89 meters) to top of concrete. The test shaft was successfully loaded to a combined side shear and end bearing of 1086 kips (4.83 MN)
Countyline Rd. Test Shaft
Anderson Drilling excavated this 42-inch (1070-mm) diameter dedicated test shaft a total length of 16.3 feet (4.95 meters) to top of concrete. The test shaft was successfully loaded to a combined side shear and end bearing of 1348 kips (6.00 MN).
Broadway Viaduct
Anderson Drilling excavated this shaft to a total depth of 48.1 feet (14.65 meters) from ground surface. The shaft started by advancing a 60-inch (1524-mm) O.D. temporary casing to the top of rock. A 54-inch (1372-mm) diameter auger was used to excavate the 30-foot (9.13-meter) rock socket in the dry condition. The reinforcing cage with attached 34-inch (670-mm) diameter O-cell was then inserted into the excavation and allowed to settle into a seating layer of wet concrete. The remaining concrete was then pumped through a pipe located near the base of the O-cell assembly. The test shaft was successfully loaded to a combined side shear and end bearing load of more than 14,700 kips (65.9 MN).
Loadtest would like to thank Mr. Jim Toole and Ben Carnazzo of Southeast Corridor Constructors, and Mike Waldren of Anderson Drilling, and the many representatives of the CDOT, for all their assistance and support.