Four CKE1350 crawlers carry the load on Britain’s biggest station box
A quartet of Stage V Kobelco CKE1350 crawler cranes is working the diaphragm-wall and piling phase at High Speed 2’s Old Oak Common station, where ground engineering specialist SB3 faces a tight site and a near-continuous programme.
Two new machines, two from the fleet
The SB3 joint venture — Soletanche Bachy with Balfour Beatty Ground Engineering — has four Kobelco CKE1350 crawler cranes committed to the station box at Old Oak Common (OOC), the £1 billion main station being delivered for HS2 by the Balfour Beatty, Vinci and Systra (BBVS) joint venture. All four are Stage V/Tier 4 Final machines.
Two of them are new, handed over to Balfour Beatty in January 2021 specifically for the OOC work. The remaining pair joined them on site across April and May, and the whole group is expected to stay for roughly 12 months.
Duties split two ways. Two cranes support construction of the station box’s diaphragm walls; the other two handle general lifting, including cages and piling rebar.
“Two of the four machines are playing a supporting role during construction of the station box’s 1.8km-long, 25m high diaphragm walls, while the other two are being utilised for general lifting duties, including lifting cages and piling rebar.”
— Nick Moon, Business Manager – Crawler Cranes, Tower Cranes & Piling Equipment, Balfour Beatty Plant & Fleet Services
Kitted out for a confined site
The two newest CKE1350s arrived with a 61m main boom and 18.3m fly jib. During commissioning both were retrofitted with a Groeneveld automatic lubrication system, which services bearings, gears, pins and bushes without manual intervention, and given ROPS/FOPS protection to doors and windscreens.
Because OOC is, in Moon’s words, “a tight site”, BBVS added an Orlaco camera system with winch view and load zoom, plus its own 360-degree camera set-up. Kobelco supplied Cab Care cab guards to protect the machines in transit.
In service the cranes are rigged shorter than their maximum: two are running a 27.4m main boom and two a 36.6m boom. Maximum lift across all four is 35 tonnes at 20m radius. Lifting gear on site includes a 70-tonne three-sheave hook block, a 35-tonne single-sheave block and a 13.5-tonne ball hook.
The scale of the box
Old Oak Common will be the largest sub-surface station in the UK. The box measures 850m long, 70m wide and 20m deep, and building it means excavating 740,000m3 of London clay. The diaphragm walls run to 1.8km in length, with 25m-deep bored piles providing internal support to the station superstructure above.
Fourteen platforms are planned in total, six of them 450m-long high-speed platforms sitting underground within the box and reached by twin tunnels heading east towards the eventual southern terminus at Euston.
“Our crane fleet is over 70% Kobelco. They’re very well-known and tested cranes, and as such were added to the lifting plan in 2020. They’re simple and easy to operate machines, that are extremely reliable, making them ideal for long term projects, such as HS2.”
— Nick Moon, Balfour Beatty Plant & Fleet Services
Source: Kobelco — Photos: Kobelco
Crane facts
- Cranes: 4 x Kobelco CKE1350, Stage V/Tier 4 Final
- Delivered: two new units, January 2021; all four on site April–May 2021
- Supplied boom: 61m main boom, 18.3m fly jib (new units)
- Working configuration: 27.4m boom (x2), 36.6m boom (x2)
- Maximum lift: 35 t at 20m radius
- Hook gear: 70 t three-sheave block, 35 t single-sheave block, 13.5 t ball hook
- Station box: 850m long x 70m wide x 20m deep
- Diaphragm walls: 1.8km long, 25m high
- Excavation: 740,000m3 of London clay
- Contract value: £1 billion (OOC main station)