Crossrail Track Alignment Design

 

Stuart Maher Limited's Contribution

 

Provision of track design services, including the production of horizontal and vertical alignments for Crossrail (overall value £15.9bn), specifically the Central Section from Westbourne Park in the West to Stratford and Abbey Wood in the East. Alignment design checks have been carried out against CRL standards, together with S & C designs/checks for locations along the route. In so doing, the horizontal design and cant application has been optimised for the train speed profile.

 

Other studies have been carried out, including a study on behalf of Scott Wilson and Network Rail to determine if the scissors within the tunnel portal structure could be replaced by two separate crossovers.

 

We have also been heavily involved in the Westbourne Park turnback facility (Grip 3/4). The revised design has been driven by the requirement to ensure that 6 tracks remain operational in and out of Paddington during the construction of Crossrail. The design solution has been further complicated by various other constraints and requirements including:

 

• Train Operations/movements/speeds – maintenance of existing linespeeds on Network Rail infrastructure; minimum connection speeds of 50mph onto NR infrastructure; minimum speeds of 25mph in turnback sidings; minimum platform lengths of 250m between top of ramps.
• S & C - Sufficient space to be allowed to enable a construction hoardings to be erected
• Vertical Alignment - Sufficient space to be left between S & C for vertical curves; CRL tunnel flood protection level to be allowed for in the vertical design; some of the existing vertical clearances are less than Special Reduced; new vertical alignment is to allow for full normal OLE clearances.
• Signalling and OLE – maintenance of existing gantry locations; achievement of minimum track lengths to enable desired speeds in sidings; minimum clearances between rail and structure soffits to ensure a compliant catenary design.