In May, 2013 Dragados Sisk Joint Venture (DSJV), the contractor constructing Crossrail’s Eastern running tunnels, approached WWL ALS (Wallenius Wilhelmsen Logistics Abnormal Load Services UK International Limited) to discuss the practicality of delivering Tunnel Boring Machine (TBM) ‘Jessica’ from Stepney Green, east London through to Limmo Peninsular, east London as part of the Crossrail Eastern Tunnels contract C305.
The challenge from DSJV was to transport the 1,300 tonne Herrenknecht S-721 TBM and back-up equipment in as large individual components as possible to enable DSJV to achieve the relocation quickly, efficiently and cost-effectively. For such a large-scale project nine months of intensive planning was required to determine a suitable route, obtain permits and liaise with multiple statutory authorities regarding the removal of street furniture, traffic management and street parking suspensions. The process required WWL ALS’ Project team to secure the necessary Be16 Special Order, VR1 and TTRO permits.
Extensive surveys were undertaken by WWL ALS to determine possible routes for this project. As part of this planning process innovative 3 dimensional laser mapping was used on dual carriageway sectors of the route with high traffic density, for scanning overhead gantry, bridge and tunnel heights and widths where manual means of checking clearances would be too hazardous. Two optional routes were identified, and the least problematic option was selected to cause minimal disruption to residents and other road users. The route taken by all loads was eastbound via the A13 Limehouse Link Tunnel, with a height and width clearance of just a few centimetres for the largest items, and it also involved travelling contra-flow on a 750m section of this major arterial route (A13) for the two largest loads.
WWL ALS’ project team, headquartered in Hull, organised and closely supervised deliveries over a four week period for this challenging operation, concluding in April, 2014. TBM ‘Jessica’, which was dismantled and transported by road two months after completing a 2.7 kilometre underground drive from Pudding Mill Lane, involved a total of 26 x abnormal loads plus ancillary equipment. Due to the congested nature of the inner-city route, between seven and twelve police escort vehicles were required for each abnormal load movement in addition to the private escorts provided by WWL ALS.
An assortment of low loader and semi low loader vehicles were used, with a maximum gross vehicle weight (GVW) of 114 Tonnes, and the time taken from collection to delivery of cargo was on average 90 minutes per movement. The largest items were transported towards the end of the project, involving loads with maximum dimensions up to 18.20 metres long, 7.10 metres diameter wide, 4.35 metres high and maximum weight 72 tonnes. The Metropolitan Police have commented that “these were the widest loads moved within central London since records began”.
WWL ALS’ Project team ensured that TBM ‘Jessica’ made the smooth 5 kilometre journey from one of Europe’s largest mined caverns at Stepney Green to Limmo Peninsular (Canning Town), east London within the scheduled timescale and budget for the project, where the TBM has been reassembled to commence work on the final Crossrail tunnels between Limmo Peninsular and Victoria Dock. Within the next month WWL ALS will commence the relocation of TBM ‘Ellie’ (a sister machine to TBM ‘Jessica’), again from Stepney Green to Limmo Peninsular. http://www.crossrail.co.uk/news/articles/tunnelling-giant-jessica-takes-a-road-trip-to-get-in-place-for-the-last-stretch-of-tunnel