The N-27 South Platte River project was a multi-phase, multi-stage project consisting of 16 different work groups, 19 subcontractors, and a Consulting Engineering inspection team. Four of the six existing bridges needed widening, and all six bridges had a Liquid Asphalt membrane placed under a 3-inch asphalt roadway. Existing millings were placed as a foundation course, while over 226,900 cubic yards of soil had to be over-excavated, dried, and replaced. A total of 135,780 cubic yards of concrete was poured over the life of the project. In order to allow placing traffic in a head to head configuration, the ramps at Exit 95 had to be closed. A 25-mile detour route for local and oversized loads was continually maintained.
IHC used a robotic stringless paving operation, equipped with a Dowel Bar Inserter and cure / texture machine. By designing the ground terrain model in house, adjustments could be made as site conditions required. An onsite surveyor made sure the paver could match existing bridge approaches and headers as needed. Having every step of the construction double checked by the next operation kept the grade accurate to .001 of a foot.
The first phase of the project paved 7.8 miles of interstate, 40-foot-wide with zero grinds and earned a 102.786% smoothness pay. The second phase required only 19 minimal grinds over 30 lane miles. All temporary pavement striping was switched to permanent, which meant the pavement markings stayed in good order throughout the life of the project. The 24-hour traffic control on site kept the traffic control devices in good working and neat order. All the extra efforts combined to finish the project ahead of schedule and on budget.