Balfour Beatty Wheel Timber Replacement – 2021

Client: Balfour Beatty Rail

Location: Markfield Rd, Tottenham, London UK

Scope: Installation of Specialist PMB materials installed on Rail Bridge joints UK wide

Overview:  Allied infrastructure was successfully awarded the installation of a Network Rail approved, specialised PMB (Polymer Modified Bitumen material) produced by Colas. The material would be used to fill joints either side of newly installed Longitudinal Rail timbers situated within a steel trough at Rail Bridge in the London borough of Tottenham on both the up and down tracks.

The Wheel Timbers are being replaced because they are rotten with many of these timbers having been installed over 25yrs ago. The works were undertaken within a 24-hour closure completing 1no track each weekend, over 2no weekends, but with the planning in place to undertake both tracks if the programme could be beat. The advantage of having Allied onboard was the size of its labour resource and the knowledge and expertise with bitumen installation works in high intensity, short duration working windows.

Scope of works: BB Rail took possession of the Rail Bridge at approx. 00.30am on the Sunday morning. They then isolate the lines and set up the site. Once the Rail had been cut and removed from the bridge, the crane was set up and the existing timbers removed by 06.30am.

Following the successful removal and preparation of the Up Track, It was decided at the hourly programme review at 08.00am that we would proceed with the DOWN Track within the same shift. This meant that a further 2no 4.5 Linear metres Wheel Timbers had to be removed and prepared for the Bitumen.

Allied had arranged to send in 2no gangs of 6no skilled men with the necessary specialist plant and materials to be on site for both a day and night shift. The PMB Asphalt that was being used for the base had arrived on site for 10.30am. By this point both the UP and DOWN track timbers had been removed and prepared ready. The Asphalt base was laid by hand with the site engineer dipping the trough every 100mm in length to maintain a tolerance of 3mm across the base material. Once complete the new Timbers were installed along with the new section of rail and rail furniture.

Installation of the COLAS Joint ‘Grip H Grade’ PMB materials was started at 16.30. The material was installed in layers not exceeding 50mm and allowing time between layers for cooling to eliminate shrinkage on the final layer. The final layer of the Colas ‘Joint Grip’ was the ‘Joint Grip IS Grade’ which is a softer Grade of material to the ‘Joint Grip H Grade’ making it ideal as the final layer with its additional flexibility properties.

"The Joint Grip material was selected due to its specially designed and engineered blend of Bitumen and Polymer which not only increases the elastomeric properties but also   provides the material with extra strength, high cohesiveness and resistance to fatigue, stripping and Increased resistance to deformation, making it a favourable material for infrastructure.’’

Allied had completed the Bitumen installation works to both Tracks by 18.30, giving BB Rail additional time to complete the rest of the Rail alignment works and successfully hand back the project for 02.00am on Monday morning.

"Another fantastic shift from Allied. We had really good outputs and great attitudes from all involved! The tarmac level was spot on, and Carl managed the bitumen installation fantastically!’’ 

Kieran Moore – Balfour Beatty (BB) Delivery Engineer

Lee Eatwell – Allied Infrastructure’s Project Manager stated

“A real collaborative working attitude adopted by everybody involved with rigorous planning and detailed logistics plans, coupled with good teamwork was essential, working in a difficult, confined environment resulting in the successful delivery of this project.”

Summary:

• Decreased programme duration eliminating the need for a second weekend.

• 1.5 Tons of material batched on site to quantities demanded per bridge location

• Future works secured since awarded

• Access restraints overcome involving materials and operators holding at on ‘’off site’’ compound location in a ready to go state. Once the call was received from BBR, the team would selectively head to the Bridge location. Working in the manner reduced the plant at site-controlled staff numbers on the bridge.

• Other bridges completed for the Network Rail Wheel Timber replacement scheme include

            Fox Bridge - Witham

            Rye Mill Lane - Witham

            Ulehams Farm Rail Bridge - Chelmsford