DETAILED DESIGN OF TEMPORARY FOUNDATION SLAB & VERIFICATION OF IMPACT ON EXISTING IMMERSED TUBE TUNNELS AND APPROACH STRUCTURE
Hampton Roads Bridge-Tunnel Expansion (HRBT)
SUMMARY
Slab thickness required: 1 ft, and a top and bottom reinforcement of W8-D8 @4”.
• The movements in both structures (ITTs and Approach Structure) are within the permissible range: a total settlement of 1.5 inches with a differential settlement of 0.5 inches.
The I-64 Roads Bridge-Tunnel in southeastern Virginia, between the cities of Hampton and Norfolk, has long been one of the most congested corridors of the region. The existing 3.5-mile facility consists of two, 2-lane immersed tube tunnels on artificial islands with trestle bridges to shore. These tunnels opened in 1957 (current westbound lanes) and 1976 (eastbound lanes) and are approximately 7,500 feet long.
The Hampton Roads Bridge-Tunnel (HRBT) Expansion Project will ease this congestion by widening the 4-lane segments of the I-64 corridor in the cities of Hampton and Norfolk. As part of the HRBT Expansion Project CYMI Industrial asked AZIERTA for a design of the Temporary Relocation of VDOT MV and SCADA utilities.
Hampton Roads Connectors Partners asked AZIERTA for the design of a concrete slab to be located on the northwest area of the South Island. This slab will be used to contain all the equipment needed for a Water Treatment Plant and a Slurry Treatment Plant. The design presents two ground movement analyses, one to evaluate and verify the impact this new slab may have on the existing Immersed Tube Tunnels (ITTs) running underneath and another one to evaluate and verify the impact that the construction offices to be placed near the Approach Structure may have on that structure.