London Office: 020 4566 9616 Contact us

Case studies

Feltham – Signal Screens

Civils Design Geotechnical Design

Project Commenced: November 2020

Project Completed: April 2021

Client: Network Rail

 

About the Project

On the Feltham & Wokingham Resignalling Programme (a major project for Network Rail to renew life expired Signalling, Telecoms and Power assets), BCM Construction were engaged to undertake the GRIP 4-8 Design and Construction works associated with Phase 2 of the project. Network Rail identified a read-through risk with one of the Phase 1 signals where LUL drivers on an adjacent line could react to this signal instead of the one on their line. 

The solution was to install four screens between the Network Rail lines and the LUL lines to obscure the new signal from the view of the LUL drivers. 

BCM Construction engaged Equate design to provide a Form F002 and F003 design for the design of the signal screens and associated piled foundations, with specialist input from the structure manufacturer and pile installer. Within this remit Equate Design undertook the Civils Design CRE role to manage the process through the assurance process. 

 

The Challenge 

The proposed location for the signal screens was located between two lines with limited access availability. A solution was required that was both quick to install, but provided adequate adjustment as the line of site varied due to the approach of the LUL line being situated on a curve. 

 

The Solution 

Driven tubular steel piles provide an efficient means of delivering a stable foundation that can be quickly installed using road rail plant. The Piles used for this design were surplus oil/gas pipe reducing the carbon footprint of the design. 

By close liaison with the superstructure designer, a system was developed to providing adjustment to account for any pile installation tolerances, whilst allowing adequate lateral and vertical adjustment to the position of the screens ensuring complete obscuration, though this was limited to ensure that future adjustments would not interfere with standard structure gauge clearances. 

 

The Deliverables: 

  • Topographical Survey – prior to any design works, the existing site was surveyed to facilitate the design. 
  • Production of network Rail Form F002 and F003 design submissions. 
  • Undertook Contractors Engineering Manager (CEM) role 
  • Undertook Contractors Responsible Engineer (CRE) Design & Construction roles 
  • Coordination drawings to accompany design submission, providing construction setting out and ensuring compliance with Network Rail gauge clearances. 
  • Design coordination and assistance with the development of the signal screen design. 
  • Design coordination and review of the pile design. 
  • Provision of guard boarding to electrified third rails, reducing risk to site personnel during inspection and maintenance operations 

 

Outputs and Benefits:

Short Installation Time: By using a single pile for each signal screen, and with the complete solution being made from prefabricated steelwork with bolted connections, the installation time was kept to a minimum with no need to wait for materials to cure, as would be expected for concrete foundations. 

Minimal track disturbance: Piled foundations avoid the risk of undermining adjacent tracks, which can be an issue with concrete pad foundations. 

Eco friendly: Surplus steel oil/gas pipes used for piles.