UK — Birmingham Office — A138 (Old A12) Chelmer Viaduct Replacement; The Cube 199 Wharfside Street B

Descriptions

The A138 Chelmer Road in Chelmsford, Essex, between the junction with A414 Essex Yeomanry Way, known as ‘Army and Navy Roundabout’ and the Chelmer Village Way Roundabout, and including land either side of the A138 of 50 m approximate overall width. The site is situated over the River Chelmer and includes a substantial area of river flood plain. The total length of the scheme is 0.9 km.Nature and extent of the works.Construction of a new multi-span viaduct and approach embankments, and the demolition and removal of the existing multi-span viaduct and approach embankments.Construction of an off-line 17 span, 400 m long composite steel beam/r.c deck slab viaduct on r.c. piled support piers. The 16 m wide viaduct carries the 3-lane A138 carriageway over the River Chelmer and its flood plain at a height of 5.5 m. There are architectural cladding features to edge beams, the river span and abutments.Low level approach embankments are 500 m long, including a 90 m length of r.c box culverted flood relief structure. Other features include drainage attenuation ponds, foot-way/cycleway facilities and landscaping.The site is crossed by numerous statutory utility services, requiring diversion works, and is bounded by busy terminal road junctions, which require carriageway tie-in works to the new alignment.The existing multi-span reinforced concrete viaduct (including concrete support structures and foundations to below ground level) are to be demolished and removed from site. Approach embankments are also to be removed, and the site returned to flood plain suitable for grazing use.All construction and demolition activity will require careful consideration to maintain the safe operation of highways, rights of way, utility services, the river and flood plain facilities. Much of the scheme implementation is subject to detailed planning consent, which places constraints on design, methods, and programming etc., hence contractor design elements are limited to temporary works and demolition operations. Completion of the scheme is targeted for late 2014.The value of the work is estimated at approximately 21 million GBP.