Plum Creek Interchange
Plum Creek Interchange in Castle Rock Colorado, Drilled Shafts - 24, Length - 20 ft. to 55 ft., Diameter - 30 in. to 54 in.
General Contractor and Owner:
Edward Kraemer and Sons, Colorado Department of Transportation (CDOT)
This project was challenging both due to limited access and drilling close to Plum Creek. As you can see in several of the pictures, we were in close proximity to the existing bridge structure, the rig was located close to traffic, and at times our swing radius was in traffic lanes necessitating very close coordination with the general contractor traffic control and spoils removal.
Temporary casing was used in most all holes due the presence of water but for one hole we encountered old concrete obstructions no doubt discarded there years ago. You can see the obstructions in the pictures. Had we attempted to drill through those obstructions severe caving would have occurred. Instead, a flow fill technique was used in which the hole is filled with a lean concrete and left to cure overnight, redrilled past the obstruction the next day, and the process is repeated until the proper depth is reached.
This area near the foothills of the Rocky Mountains was a tropical rain forest 65 million years ago. Ancient palm frond artifacts were discovered and reported to be some of the oldest evidence ever found.