Lyminster Bridges

About the project

This scheme involved the construction of 2 no. overbridges for our client, Breheny. The first bridge was a 17m span, prestressed concrete overbridge spanning a road. The second bridge was a 30m span, prestressed concrete overbridge spanning a railway: an 800T crane was required to install the deck beams. The bridges were critical activities in Breheny’s Lyminster Bypass Project. The client contracted these structures to Enable Infrastructure (formerly BCM Construction) because of the latter’s capability and experience of working in a rail environment.  Enable Design (formerly known as Equate Design) was engaged to support Enable Infrastructure in the assurance processes and temporary works design.

The challenge

Both bridges were constructed over live traffic (rail and road), which presented logistical challenges. Bespoke access solutions were required to facilitate construction in this high-risk environment. The railway bridge had very limited track possessions; thus, meticulous planning and strict adherence to programme were required.

Whilst planning the construction of the deck, Enable Design ascertained that the permanent works designer had not considered temporary load cases in their modelling of the bridge. We coordinated the permanent and temporary works designers, the client and Network Rail to resolve these CDM issues.

The solution

Enable Design managed the supply chain in the development of multiple temporary works schemes to provide access, crane support, formwork/falsework and also temporary beam restraints. These were to compensate for the permanent works design not taking into consideration construction phasing (interim load states etc).

Enable Design managed the NR assurance process, including the production of temporary works Forms 002 & 003s. We also provided the project Contractors Engineering Manager (CEM).

The Team

• Project Manager
• Engineering Manager
• Civil Engineer

The deliverables

• Managed engineering interface and assurance processes with Network Rail.
• Management of AMP process, production of AMP forms.
• Managed and coordinated 3 no. Temporary Works Design CREs from across our supply chain – EFCO, AJMS & Wentworth House.
• Preparation, review and approval of Construction Phase Plan and Work Package Plans.
• Produced Temporary Works F002 & 003s for:
  • Crane foundations
  • Abutment formwork
  • Deck edge protection
  • Precast parapet fixings
  • Beam restraints
• Positional monitoring of temporary works during construction.
• Identification/resolution of CDM issues associated with the permanent works design.