Owner
                                
                                
                                    
            Crossrail Ltd. - TfL
      
                                
                             
                                                                            
                                                                            
                                                                            
                                
                                    Timeframe
                                
                                
                                    February 2011
                                                                             — December 2012
                                                                                                        
                             
                                                                            
                                
                                    Services performed
                                
                                
                                    
            Tunnel design, engineering support, geotechnical engineering and site supervision services were provided.
      
                                
                             
                                                                            
                                
                                    Description
                                
                                
                                    
            Contract C305 is the biggest design-bid-build construction contract of the Crossrail (CRL) project and includes the eastern running tunnels of CRL's central section with launch shafts and SCL launch adits for TBMs at Limmo Peninsula, SCL caverns and launch adits for TBMs at Stepney Green and 10 SCL cross passages between the running tunnels with lengths up to 30m. At the Limmo Peninsula site a 40m deep and 30m diameter SCL shaft was built. At the shaft bottom in Stepney Green, two 30m long and up to 10m wide SCL launch adits were constructed followed by two 14m high and up to 18m wide, SCL caverns with single sidedrift and double sidedrift cross sections.
      
                                
                             
                                                                            
                                
                                    Geology
                                
                                
                                    
            Geological locations of the cross passages vary from London Clay to Lambeth Group and Thanet Sands.