Client: Network Rail HQ Services Provided: Corus was commissioned by Network Rail HQ to complete a series of assignments. The National Gauging Project was set up to deliver the control processes to avoid the need to re-gauge the network at each and every change of vehicle type on a route. It also supplied the control mechanism to provide the continuing safety requirements for trains operating in areas of reduced clearances. Corus' extensive experience includes: completing surveys, feasibility reports and detailed designs for the introduction of the GNER Class 373 Eurostar North of London, Class 333 and 170 passenger vehicles, and the Virgin Tilting Train on the WCML. Also, the clearing of freight gauges on a variety of routes. Track Walkouts The work undertaken on the track walkouts included: - Recording and checking information contained on datum plates fixed to a line of route structures
- Identifying structures where no Datum Plates were fixed
- AWS magnets recorded and utilised to identify suitable locations for the GPS survey works.
Co-ordinated Surveys of Station Platforms
It was established by Network Rail's Project Team that 94 platforms required surveying, as no current information existed. Installation of Survey Control at Stations using GPS Techniques
In order to obtain accurate co-ordinate information, three control points have been installed at 50 stations throughout the rail network and GPS surveys have been undertaken using a TRIMBLE 4800 Dual Frequency GPS total receiver. Surveys of AWS Magnets using GPS Techniques
To enable the establishment of accurate control, approximately 750 magnets and 140 'key junctions' have been surveyed to enable adequate coverage throughout the rail network. Installation of Datum Plates
A further aspect of the project is the installation of Datum Plates at station platforms and line of route structures (where required). These Datum Plates will form the on site control with respect to track position and infrastructure. | 
