COLLETT & SONS MOVE A TUNNEL BORING MACHINE, WEIGHING A TOTAL OF 215 TONNES, OVER 27 MILES IN THREE DAYS. ANDY ADAMS REPORTS.
With the National Grid being awarded the £100m contract to excavate a 5km tunnel under the River Humber from Paull to Goxhill to carry a replacement gas pipeline, Fracht UK Projects appointed Collett & Sons to transport the disassembled tunnel boring machine from Immingham docks to the Goxhill site. The tunnel boring machine, named Mary, was transported from its manufacturer in Baden-Wurttemberg, Germany, by Fracht AG to Rotterdam for onward shipment to Immingham.
Fracht UK and Collett & Sons worked together, 18 months ahead of the TBM’s arrival, to devise a plan for delivery. The machine consisted of four components: a 30-tonne cutter head (4.8m long x 4.5m high x 4.5m wide), a 70-tonne shield (4.5m long x 4.4m high x 4.5m wide), a 95-tonne machine can (9.6m long x 4.4m high x 4.5m wide) and the 20-tonne tail shield (3.8m long x 4.5m high x 4.6m wide).
On arrival at the DFDS Immingham Terminal each of the four components were surveyed and Inspected by Fracht UK before being loaded onto Collett’s trailers for the 27-mile journey to the National Grid site in Goxhill, North Lincolnshire.
The route posed several obstacles which required meticulous planning to ensure that the 40m long x 4.6m high 4.5m wide loaded combination would successfully navigate the landscape. With numerous tight bends and turns identified along the route several swept path analysis reports using Ordnance Survey Mastermap Data were completed. The largest loaded component, the 29m-long machine can, was used by the analysis team to mimic the trailer and vehicle’s behaviour at select parts of the route to identify any landscape problems and manual steering requirements.
On exiting Immingham Docks, the route passed through South Killingholme and along the A180, joining the A15 before taking a tight right turn on to the B1206 towards Barrow. Once in Barrow Upon Humber, in order to enable an extremely tight right turn, the steersman had to employ the manual steering capabilities of the self-propelled power boost module.
On approach to the Thornton Road and College Road crossroads the team faced another extremely tight turn, this time on the left. The removal of five sections of Armco barrier, one concrete sign post, a blind summit sign, along with the levelling of a splitter island were required. The northeast side of the junction also had to be resurfaced with stone three metres from the kerb, to allow the team to navigate this section of the route.
At this point the tractor unit was disconnected. Using remote control, the self-propelled module manoeuvred the cargo around the tricky bend and past the junction to a clear distance, the cargo was then reversed right, providing a clear run over the crossroads. After negotiating the junction, the tractor unit was re-coupled.
On the approach to Goxhill parking restrictions had been put into place on both sides of the residential area for approximately one mile. Tree pruning had also been undertaken to provide a 5m-high, 5.5m-wide clearance.
After the traffic restriction zone, the convoy crossed Ferry Road Rail Bridge. Here, the trailer’s hydraulic suspension was raised to allow the low deck to safely clear the crest, while the entire combination was manoeuvred at crawl speed in the centre of the carriageway until clear of the structure.
To navigate the exit from the village of Goxhill through Goxhill North End, parking restrictions again had to be implemented on both sides of the road and each of the three smaller loads, the cutter head, shield and tail shield were navigated through the residential area. For the heaviest load, the 95-tonne machine can, the team once again had to employ manual steering and utilised the power boost module to manoeuvre the combination into position for the approach to the delivery site.
The final approach also required extensive modifications. Temporary road signs had been removed, any loose items had been cleared from the site and five separate areas of grass verge had been resurfaced. With the average 2.8m width of East Marsh Road falling below the 3m axle width of the loaded components, the team had 30m of plating and hardcore installed from the junction onwards to ensure the vehicle and trailer’s stability. With the entrance to site having been widened and the site gates dismantled, each load was safely delivered to the gas pipeline project site.
Three and a half hours after departing from the Port of Immingham the first two loads, the cutter head and the shield, completed the 27-mile journey, under Humberside Police and private escort, arriving on site by mid-afternoon. The empty trailers left the site, still under police escort due to the size of the road, and were returned to the company’s heavy lift depot in Goole. The following day, the loaded tail shield and machine can left the port at 09:30hrs to replicate the journey to the site.
Over three days all four cargoes were transported. Once assembled Mary will be used to build a replacement high pressure gas pipeline from Goxhill to Paull. The project is due for completion in 2019, and once built it will be the longest gas pipeline in a tunnel, inserted in a single string in the world.