BROOK FARM, THORPE ST ANDREW, NORWICH Proposed Middle Road Bridge Crossing of Norwich to Sheringham Railway BROOK FARM, THORPE ST ANDREW, Railway NORWICH Proposed Middle Road Bridge Crossing of Norwich to Sheringham Railway (Bittern Line) Sheringham to NORWICH Norwich ANDREW, of Client: Lothbury Property Trust Company Limited ST Engineer: Create Consulting Engineers Limited 15 Princes Street Norwich Crossing Norfolk THORPE NR3 1AF Bridge Tel: 01603 877010 Email: [email protected] FARM, Web: www.createconsultingengineers.co.uk Road Report By: Barrie Anderson, BEng (Hons) BROOK Checked By: Jonathan Cage, BEng (Hons), MSc, CEng, MICE, MCIHT Middle Reference: BA/CS/P16‐1148/09 Date: September 2017 Proposed Brook Farm, Thorpe St Andrew, Norwich Proposed Middle Road Bridge Crossing Norwich to Sheringham Railway BROOK FARM, THORPE ST ANDREW, NORWICH Proposed Middle Road Bridge Crossing of Norwich to Sheringham Railway (Bittern Line) Contents 1.0 Introduction 2.0 Purpose of Bridge 3.0 Design Constraints 4.0 Form of Construction and Methodology 5.0 Highway and Access 6.0 Conclusions Registration of Amendments Revision Revision Revision Amendment Details and Date Prepared By Approved By Ref: BA/CS/P16‐1148/09 Page 1 Brook Farm, Thorpe St Andrew, Norwich Proposed Middle Road Bridge Crossing Norwich to Sheringham Railway 1.0 INTRODUCTION 1.1 Create Consulting Engineers Ltd have been commissioned by Lothbury Property Trust Company Ltd to design a new road bridge providing a diversion of Middle Road across the Norwich to Sheringham Railway Line (Bittern Line) in Thorpe St Andrew, Norwich. 1.2 The proposed bridge is to the immediate north of an existing bridge crossing on Middle Road. Refer to Site Location Plan extract below Figure 1: Site Location Plan Extract 1.3 This document provides supporting information in respect of a formal planning application for the provision of the proposed bridge and its immediate approaches. The report provides details of the main constraints around the bridge construction, the key design elements and outlines the methodology that will be used during its construction. Ref: BA/CS/P16‐1148/09 Page 2 Brook Farm, Thorpe St Andrew, Norwich Proposed Middle Road Bridge Crossing Norwich to Sheringham Railway 2.0 PURPOSE OF BRIDGE 2.1 This bridge is part of a proposed realignment and improvements scheme being undertaken for Middle Road. The diverted section of Middle Road will provide a link between two lengths of new link road from Plumstead Road to the north and Brook Road, within Broadland Business Park, to the south. The completed link road is proposed as part of an already approved planning permission. Refer to Planning Application 20090886 for further details of this scheme. 2.2 The existing Middle Road Bridge will be retained as a dedicated footpath/cycleway link, but with motor vehicle use prohibited once the new bridge and link road are fully operational. 2.3 The link road is intended to form part of an internal distributor road which will link Broadland Business Park with the residential areas to the north eats of Norwich. One of its primary functions is to act as a public transport corridor. 2.4 The bridge itself is to be 12.7m wide, comprising a 6.5m carriageway, a 2.0m footway, a 3.0m combined footway/cycleway and 2 No. parapets. 2.5 The approaches either side to of the bridge will be formed by new embankments with the abutments being constructed clear of Network Rail land. A detailed landscaping scheme is proposed to accompany the bridge scheme which has been prepared by Shiells Flynn and forms part of this application. Ref: BA/CS/P16‐1148/09 Page 3 Brook Farm, Thorpe St Andrew, Norwich Proposed Middle Road Bridge Crossing Norwich to Sheringham Railway 3.0 DESIGN CONSTRAINTS 3.1 There are a number of constraints which have dictated the design and will ultimately have an effect on the construction methodology: An allowance for the potential electrification of the Norwich to Sheringham railway line has resulted in the proposed bridge having to be set at a higher level than the existing Middle Road Bridge to the south. With a minimum clearance of 5 m to the rail from the underside of the bridge. This is to enable Network Rail in the future, to install overhead cabling and the associated safe zones without impacting on the new bridge structure. A number of trees will be required to be removed along the existing railway embankment to facilitate the construction of the bridge and to allow future maintenance. An existing 300mm Medium Pressure Gas Main is present in the immediate vicinity of the railway embankment. Due to its location, which has been verified by trial holing on site, this is to remain insitu with the abutments and piling set back on the western side to give the required clearance zones. Full agreement to the finalized design will be sought from Cadent Gas who are responsible for this pipeline. Existing 33kVA overhead electric cables are in the immediate vicinity of the proposed bridge and due to the increased height of the bridge it is necessary to divert these, with UKPN’s preference to have them underground. The proposed location of the diverted route has an effect on the proposed bridge abutments on the eastern side. Middle Road is public highway and therefore a temporary stopping up order will be required during the construction process, especially during the bridge beam lifts. Ref: BA/CS/P16‐1148/09 Page 4 Brook Farm, Thorpe St Andrew, Norwich Proposed Middle Road Bridge Crossing Norwich to Sheringham Railway 4.0 FORM OF CONSTRUCTION AND METHODOLOGY 4.1 Due to the constraints highlighted above and the proximity to a live railway line it has been necessary to very carefully consider the proposed bridge construction. The philosophy is to have as much of the bridge constructed off site in factory controlled conditions. The Bridge beams and deck will be delivered to site and lifted into place. 4.2 The option chosen is for Pre‐Cast concrete beams, insitu concrete abutments supported on Continuous Flight Auger (CFA) piles. The bridge itself will have concrete parapets with a deck sufficient for the anticipated traffic. 4.3 The embankment either side of the bridge will be a maximum slope of 1 in 3 with landscaping proposed to provide screening. The parapet height will be up to a level of approximately 34.670m AOD with the underlying rail being at a level of 26.750m AOD. 4.4 Due to works occurring over the railway line, it will be necessary to apply to Network Rail for overnight possessions of the railway line. Full detailed risk assessments of the piling operations and bridge beam lifts will be agreed in advance with Network Rail before construction. These possessions will enable the precast beams to be lifted safely into place. These possessions will be arranged well in advance with Network Rail in accordance with their statutory procedures. 4.5 Given the proximity of the medium pressure gas main as well as the railway line it will be necessary to carry out vibration monitoring of both the gas main and the railway track during the works to ensure neither are affected by the construction operations 4.6 It is intended that the Bridge works will be constructed as part of the overall Link Road contract therefore contractor wealth fare and compound facilities will be provided as part of the main scheme. Ref: BA/CS/P16‐1148/09 Page 5 Brook Farm, Thorpe St Andrew, Norwich Proposed Middle Road Bridge Crossing Norwich to Sheringham Railway 5.0 HIGHWAYS AND ACCESS 5.1 As part of the construction works, Middle Road will need to be temporarily closed to enable the bridge and approaches to be installed. It is intended to minimize the closure of Middle Road, however, the recently constructed Northern Distributor Road will provide an effective diversion route. Prior to this, and to minimise disruption, the diversion of the overhead electricity cables will be undertaken, this however should only require temporary traffic management. 5.2 It is intended, following completion of the bridge works, that Middle Road in this vicinity will be closed to all vehicular traffic with traffic being routed over the new bridge. The existing bridge will be retained for pedestrian traffic. A Traffic Regulation Order (TRO) will be applied for with Norfolk County Council to enable this to occur. 5.3 The whole of the works will be undertaken under the terms of a Section 278 of the Highways Act agreement. The land required for the new road will be dedicated as public highway immediately on completion and the new bridge will then be opened to traffic. 5.4 All of the main components of the bridge will be delivered using the A47(T) which is the main trunk road in the area, linking East Anglia with the Midlands. The existing Broadland Way and a section of the new Link Road will be then used as the main delivery routes to the Bridge site. Ref: BA/CS/P16‐1148/09 Page 6 Brook Farm, Thorpe St Andrew, Norwich Proposed Middle Road Bridge Crossing Norwich to Sheringham Railway 6.0 CONCLUSIONS 6.1 It is proposed that a section of Middle Road is to be diverted over a new bridge crossing the Norwich to Sheringham Railway (Bittern Line) in Thorpe St Andrew, Norwich. The diverted section of Middle Road forms part of a wider Link Road scheme which links Brook Road to the south with Plumstead Road to the north west. It is intended that the road will form the southern section of an internal distributor road which will link up the Broadland Business Park with the residential areas to the Northeast of Norwich.