Challenge Design-Build Project Delivery Addressed

As the team studied the overall project schedule, it was apparent that this project would benefit by designing the project as one package rather than dividing the project into sections. Immediately, the design-build project manager and design manager developed a design submission schedule based on the construction start date. The overall schedule was aggressive and all team members were advised of the schedule to avoid lack of understanding of expectations.

Summary

By briefly shifting vehicles to the opposite side of the road, the design of this innovative Diverging Diamond Interchange (DDI) eliminated traditional left turns that must cross oncoming traffic. The original concept created “trap” lanes on Route 15 for traffic exiting from I-64 off ramps, which created a weave that would have been difficult to navigate. The design-build team’s concept eliminated the trap lanes and undesirable weaves and included a study of interchange movements prior to the bid. This reconfiguration eliminated the need to replace an existing signal and raised medians that were in the Request for Proposal. This ultimately improved safety by eliminating a potential obstruction to traffic, easing maintenance — especially during snow removal — and alleviating confusion on the I-64 off-ramps.

Design-Build Team

Client/Owner: Virginia Department of Transportation
Design-Builder: Corman Construction, Inc.
General Contractor: Corman Construction, Inc.
Engineers: Parsons Transportation Group, Wallace Montgomery & Associates
Specialty Contractors: S.L. Williams Co. Inc., Snead & Son Trucking LLC
Specialty Consultants: F&R, Continental Field Service
Other Key Professionals: McDonough Bolyard Peck Inc., Endesco, Schnabel Engineering, RJM Engineering
Duration of Construction: 18 months
Project Cost: $6,905,367