CAPE CHARLES, Va. — To construct two new tunnels at the Hampton Roads Bridge-Tunnel (HRBT) expansion site, crews are building concrete segments to form rings that will be put together to create the tunnels.
The Virginia Department of Transportation (VDOT) and Technopref Industries, the subcontractor for this aspect of the project, gave members of the media a tour of their Cape Charles precast plant Wednesday to demonstrate how the tunnels are being built.
"This is a huge effort," said Jim Utterback, the HRBT Expansion Project Director for VDOT, said.
Nine of the 15-ft. long segments are connected to form one ring. To build two tunnels, more than 21,000 segments need to be created to form nearly 2,400 rings.
The precise process involves molding concrete. Crews take steps to make sure the concrete is good quality. Steel fiber is added to the mix and each segment has a rebar cage to reinforce them.
Each day between two shifts, the crews make 54 segments, or six rings. So far, about 10% of the work is done, with the goal of beginning to form the tunnels at site in spring 2023.
The segments will be transported to the site by barge when ready.
"One of the things we wanted to show is that progress is being made on the project," Utterback said.
In other bridge-tunnels in Hampton Roads, large pieces of tunnels were built and then connected together. In this method, a boring machine will go ring-by-ring to create the tunnels.
"This is being done primarily to minimize the impact on the federal channel, so it will have very little to no impact on the shipping channel and the channel the Navy uses to get warships in and out of Hampton Roads," Utterback said.
Work on the $3.8 billion project has been underway since 2020 and is expected to be completed in 2025.