Jim Richings, Technical Director at Balfour Beatty VINCI Joint Venture presented a lecture on the construction of the HS2 Delta Junction near Coleshill in Warwickshire.
A video of this lecture can be viewed in the Members Area. Please log in here…Members Area
This triangular junction, with each side about 5km long, allows grade-separated interchange of the HS2 lines between London, Birmingham and Manchester. It is composed of a wide variety of structures and earthworks, all designed to accommodate existing infrastructure and natural features. It is the latest part of a significant legacy, following the canals, railways and motorways of previous generations.
The presentation illustrated some of the construction techniques employed at the Delta Junction and how they were used within the particular constraints of the individual structures. These include the Curdworth Box, the Water Orton Viaducts and the M42-M6 Link Viaducts.
Curdworth Box carries 6 lines of HS2 over the Birmingham to Derby railway line. It is an integral reinforced concrete bridge, with 3 parallel decks constructed using pre-cast concrete beams and in-situ composite decks and pre-cast parapets. The sub-structure was constructed behind temporary screens to minimise disruption to the railway.
The Water Orton Viaducts are part of a set of viaducts constructed from pre-cast concrete segments, using a continuous cantilever method of construction. This highly mechanised method allows for minimised manual handling, rapid construction and high-quality product. The piers followed a standardised pattern, allowing economy of construction materials and methods. The deck segments, weighing up to 80t, are connected using temporary post-tensioning bars, until completion of each span allows the permanent post-tensioning strands to be installed. The Water Orton Viaducts carry the north chord of the Delta Junction across the Birmingham to Nuneaton Railway and the M42 and M6 Toll motorways.
The M42-M6 Link Viaducts cross the link roads between the M42 and M6. They are a pair of trapezoidal steel box girders, with pre-cast concrete decks and parapets, constructed off-line and launched into position during road closures.
