The construction of a massive 14,500-tonne box structure, designed to carry the new HS2 line under the A46 Kenilworth Bypass in Warwickshire, has made significant progress with the successful installation of 120 enormous beams.
These concrete beams, ranging from 13 to 24 meters in length, were meticulously lifted into place by three giant cranes, forming a crucial part of the structure's top. A dedicated team of engineers worked tirelessly around the clock, completing the entire operation ahead of schedule in just 14 days.
Scheduled for completion later this year, the colossal box is being constructed on land adjacent to a section of the A46, rather than beneath the carriageway itself. This approach avoids the need for up to two years of traffic management measures. With the beams now in place, the next steps include finishing the deck—the flat surface on top of the beams—and installing parapets. In the spring, the completed structure will be moved into position under the existing carriageway using an innovative technique.
This technique involves a jacking mechanism, designed by the specialist civil and structural engineering company Freyssinet, which will push the box across on a guiding raft at a speed of up to 2.5 meters per hour, covering a total distance of 64 meters. Together with National Highways and its construction partner for the West Midlands, Balfour Beatty VINCI (BBV), HS2 has begun preparations for the box push procedure.
A section of the A46 between Festival Island (Coventry) and Thickthorn Island (Kenilworth) will be closed for two weekends next month for the initial stage of preparation work. The plan is to move the structure into position during a full closure of the A46 Kenilworth Bypass in the spring of 2025, which is expected to last up to three weeks.
Photos & Video credit: HS2
