Beaver Bridges were engaged by NRS Group to demolish the existing damaged suspension bridge that had been condemned, design, supply and install a replacement Arched Warren Truss Main span, and approach spans and stairs. The main span is a 45m main span pedestrian footway link across the River Ribble in Lancashire. We held responsibility for planning, managing, monitoring, coordinating and controlling our works including health, safety and on our worksite site.
The footbridge renewal works were funded by central Government and administered by the County Council. The main Contractor is NRS Group responsible for all civils works , with Bridging Specialists Beaver Bridges responsible for demolition and disposal of the existing structure, design, manufacture and installation to the client’s design intent, of all the steel bridge and timber works.
Beaver Bridges provided a full turnkey package (in respect of the bridging), taking the project through the design phase, integrating health, safety, and welfare into the planning and management into these works. Very careful planning of each element was the byword from the design stage through the safe removal (Figure 2) of the existing structure and forward on to complete installation. Beaver Bridges supplied all resources including staff, machinery, equipment, tools and materials. Site-specific inductions for all site staff ensured they had the skills and competency to enable them to safely carry out their relevant tasks – safely and efficiently paying attention to the local environment and general site safety including manufacture and installation, liaising with the main contractor and Council Client throughout.
The Structure
The structure was designed compliant with the following standards loading to BSEN1991, steel specifications to BSEN 1993 fabrication to BSEN 1990 the timber element by BSEN-1995 and bearings under the specification laid down in BSEN 1337. Constructed from curved steel SHS top arch members and SHS cambered bottom chords and designed as two modules for bolting together on site. The two modules were delivered to site with very tight access as was the 750t crane! following connection of the two modules and the placement, the wooden decking boards were added, thereby completing the installation.
The install was carried out under very challenging conditions, besides there being very restricted access requiring the haul route to undergo a massive amount of extending and strengthening. The Crane we employed was a 750t unit and was running at maximum ballast and fitted out with a full “Luffer” rig. The lifts were also frustrated by variable wind speeds requiring extreme diligence and skill to capture the limited weather windows, all lift plans were by Beaver Bridges in house “Appointed person” as were the tasks of Banksmen and Slingers.
