Crossrail is one of the largest infrastructure construction projects in Europe and comprises a 100 km new railway across London from Reading in the west, through new Liverpool Street and Canary Wharf stations then south under the Thames at Woolwich through to Abbey Wood.
A second spur is due to link Whitechapel with Shenfield in Brentwood, NE London. There are 42 km of new tunnels being constructed using purpose-built tunnel boring machines.
RIL staff have played an important role for Crossrail. Prof. John Reynolds and Dr Lucy Catt and colleagues have been involved in managing Crossrail’s over-water seismic surveys to aid the design of the tunnel route under Woolwich Reach and also the new station at Canary Wharf. One of our projects was to help image key geological interfaces to ensure that the tunnel boring machine would not puncture through impermeable clay into saturated sediments above the tunnel route. The ultra-high resolution seismic interpretation and 3D Ground Model we produced enabled Crossrail engineers and contractors to guide the tunnel boring machine with a precision of better than 30 cm. We were later able to determine that the seismic data cross-correlated with the observed construction logs to better than 15 cm.
The Crossrail tunnel at Whitechapel (Courtesy of Crossrail).
The reason for this news item is that BBC Two is broadcasting a documentary at 9 pm on Wednesday 23rd July about Crossrail, the £15 billion railway. In particular, it is due to describe the tunnel construction beneath the Thames at Woolwich Reach. This was a project that involved a comprehensive integration of high-resolution seismic surveys with over-water construction of boreholes, including extensive investigations for UneXploded Ordnance. Whilst this programme, the second part in a series of three, describes the actual tunnel construction, we can be proud that our staff were involved in this high-profile and highly successful project.
However, our involvement in the Crossrail project has a continuing legacy in that it, and subsequent involvement in the similarly high-profile Thames Tideway Project, has led to the development of an industry-leading workflow to manage the data journey of high-resolution seismic data and integrate them with geotechnical results from intrusive ground investigations and lab testing to form sophisticated dynamic 3D Ground Models. This workflow has been highly successful in recent years in the offshore renewables sector, and is undergoing continual improvement. Watch out for news in the coming weeks about an announcement concerning this workflow.