The first 8.15m diameter Wirth EPBM being used on the UK’s Channel Tunnel Rail Link Contract 240 looks set to finally get going again this month, following a collapse above the tunnel on 8 February 2003 (see T&TI, March 2003, p6).
Rab Brown, former CTRL project manager, now spokesperson, told T&TI that as long as the UK’s Health and Safety Executive (HSE) is happy with the geotechnical investigations undertaken following the collapse, then engineers are looking at a start date on, or around, 15 May 2003.
The contractor, Costain/Skanska (UK)/Bachy Soletanche JV, will allow the second TBM to overtake the first machine, allowing enough time for engineers to grout the area around the concrete plug in Lavender Street, and receive the go-head from the HSE.
“The second machine will move cautiously under Lavender Street, even though we have studied the area thoroughly and all necessary investigations have been carried out,” Brown said.
Proceeding at an expected rate of 12m-15m per day, the second Wirth EPBM should come parallel with the first, stationary, machine by about 7 May. It will then take another week to reach a safe enough distance to allow the first machine to restart.
