Opportunity
The original Hampton Roads Bridge-Tunnel opened in 1957. One year later, 6,000 vehicles a day on average were using it. A second tunnel opened in 1976.
The four-lane structure included bridges, trestles, man-made islands, and two lanes of traffic passing through each of the two tunnels beneath the main shipping channel. The new bridge-tunnel offered an alternative to ferries for the region’s most important water crossing.
By 2008, an average of 88,000 vehicles a day were using the crossing. That number grew to more than 100,000 during the tourist season — well beyond the original design capacity.
The need to expand the capacity of the crossing was urgent. A major challenge was the need to minimize the impact on a sensitive marine environment and to secure the necessary environmental permits and approvals. It was also vital to avoid impacting marine traffic, including US Navy operations.
Solution
Hampton Roads Connector Partners, a joint venture for which Mott MacDonald and HDR are the lead designers, was selected to deliver the Hampton Roads Bridge-Tunnel Expansion Project. At $3.8 billion, this was the largest design-build procurement ever undertaken by the Virginia Department of Transportation (VDOT).
Mott MacDonald is responsible for all design work related to the tunnel improvements, including the segmental lining design, tunnel approach structures, flood gates, and all mechanical, electrical, and plumbing facilities.
The Hampton Roads Bridge-Tunnel Expansion Project will add two new two-lane bored tunnels to supplement the two existing immersed-tube tunnels. It will also widen two four-lane sections of Interstate 64.
In collaboration with the client, we are committed to a comprehensive digital approach. The client requires us to deliver Building Information Modeling (BIM) models at specified dates, and these models are used to create a 4D simulation of the project.
Mott MacDonald is drawing on the skills of its teams in London and Prague for this project, and leveraging our multiple enterprise agreements with software firms.
We keep track of project deliverables and track technical requirements using SharePoint project sites and PowerBI. Office365 tools are used to enhance, reinforce, and support common project management principles and to collaborate between multiple offices, staff, consultants, and partners.
LeapFrog helps us understand subsurface conditions, perform interactive analysis of ground conditions throughout the evolution of the design, and use geological rules in modeling. Plaxis makes fast and efficient finite element model creation possible, offers realistic assessments of stresses and displacements, and provides powerful and versatile post-processing.
Survey123 assists in collecting data from boreholes. Data is recorded directly from the field using tablets and saved to the cloud. GPS-capable tablets save geolocation data, and dashboards can be created that draw on that data.
3D models are generated using Bentley software tools, with generative tools used to auto-generate models of the tunnels and tunnel linings. Drawings can be “cut” directly from the modeling information.
Outcome
"VDOT's largest transportation project is being constructed in the heart of a region vital to Virginia’s economy, military readiness, and regional connectivity," said Virginia Secretary of Transportation Shannon Valentine when it was announced that the contract was awarded.
This landmark day and major milestone, described by many as a win-win for Virginia, "would not have happened without close coordination and strategic partnership between the Commonwealth of Virginia and the Hampton Roads Transportation Accountability Commission (HRTAC)," according to Valentine.