As one of the largest infrastructure projects currently under construction in the United States, and the largest infrastructure program in Virginia history, the $3.9 billion Hampton Roads Bridge-Tunnel (HRBT) promises to have a generational impact on the region’s roadway network, easing congestion and enhancing travel time reliability for motorists.
STV’s Virginia team is celebrating a recent milestone made by Mary, the 46-foot tunnel boring machine (TBM) that is playing a key part in this transformation. Mary recently completed the first new tunnel at the HRBT’s North Island, marking a major achievement for the project which is widening nearly 10 miles of the I-64 corridor between Norfolk and Hampton with new twin tunnels across the harbor.
On behalf of the Virginia Department of Transportation (VDOT), STV, in joint venture, is performing quality assurance (QA) oversight of the bored section of the HRBT program. Rosmar Gonzalez, STV’s Tunnel QA lead for the HRBT Project, was present during Mary’s monumental breakthrough and described it as “impressive, robust, and resilient.”
“This special accomplishment represents the state-of-the-art in tunneling methods,” Gonzalez added. “The advancement of TBM technology in the past 20-plus years has led to a continuous increase in tunnel diameters. Now, this first new tunnel belongs to the short and privileged list of large diameter tunnels (greater than 42 feet) built in the U.S.”
The North Island milestone marked the completion of Virginia’s first bored roadway tunnel and only the third in the U.S. The TBM is named in honor of Mary Winston Jackson, a Hampton native, Hampton Institute alumna, and NASA’s first African American woman aerospace engineer.
Over her journey, Mary has mined 7,970 feet of soil and installed 1,180 rings for the first of two new tunnels in the expansion. While the tunnel will not be finished for several more months, this is one of the most anticipated milestones for the project.
STV’s full scope for the project includes:
- Performing construction QA services for the tunnel excavation and installation of pre-cast concrete tunnel lining segments.
- Performing On-site monitoring of the TBM and Slurry Treatment Plant (STP).
- Providing input for revisions of to the TBM and Tunnel Quality Plan.
- Observing construction as it is being performed, including all quality control and QA activities to ensure that inspection, testing, and correction of non-conforming work are being performed in accordance with the contract requirements.
- Monitoring installation/construction of the tunnel’s internal structures.
“We are thrilled to be part of such a historic project for the Commonwealth of Virginia,” said Kristin White, P.E., CCM, STV’s project manager. “Rosmar and our tunnel inspection team have worked tirelessly to help VDOT achieve this important milestone and we’re looking forward to continued success on the project.”
STV Senior Vice President and National Director of Tunneling and Geotechnical Engineering, Frank Pepe, P.E., said the recent milestone is a pivotal moment in the project’s timeline and demonstrates how the combination of strong tunneling professionals along with the integration of innovative technology in modern tunnel construction has led to a “remarkable evolution” in modern tunnel construction.
“Advancements in TBMs and other methods now allow for more complex and ambitious projects,” Pepe added. “These innovations have made it possible to undertake such feats of engineering once deemed too challenging or impossible. It reflects a profound shift in our capabilities.”
Click here for a detailed map of the project.
