Deck the bridge with steel and concrete.
Following an extremely busy period the team at Mountain Ash are hitting a major milestone this December with the first 175 m3 deck pour being undertaken.
The abutments to the bridge were completed earlier in the year, but due to a service diversion, the Walters Sisk JV team were only able to commence construction of the central pier in mid-June. The central pier was completed in early September, which then enabled the delivery of the large steel bridge beams for site assembly and lift preparation.
Following liaison and meticulous planning involving the client and Network Rail, the beams were installed over the railway under a 53 Hr disruptive possession on the last weekend of September. Although the weekend weather conditions were unfavourable, the team managed to install the main bridge beams successfully, with the track handed back in time for normal train services on the Monday morning. Works to the deck structure have been ongoing since, culminating in the first deck pour this first week of December 2019.
The team has also been working on the approaches to the bridge, and successfully completed the technically challenging tie-in earthworks to the South, under a 6 week road closure during the summer school holidays. Due to unforeseen ground conditions, an innovative lightweight earth retaining wall solution was adopted, which reduced the extent of excavation and made essential programme savings.
The remaining retaining wall structures are now nearing completion, with a combination of Retained earth retaining walls and conventional reinforced concrete structures to enable the widening of the existing highway on the West side of the river and railway.
We are currently working towards completion of the bridge structure in the spring, and completion and opening of the scheme by mid 2020. You can see impressive drone footage of the scheme before and after – please click here to view.