TRANSPORT AND WORKS ACT 1992 MIDLAND METRO (BIRMINGHAM CITY CENTRE EXTENSION LAND ACQUISITION AND VARIATION) ORDER INQUIRY NOVEMBER 2014

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1 TRANSPORT AND WORKS ACT 1992 MIDLAND METRO (BIRMINGHAM CITY CENTRE EXTENSION LAND ACQUISITION AND VARIATION) ORDER INQUIRY NOVEMBER 2014 NAVIGATION STREET BRIDGE DETAILS AND ASSESSMENT 1. Introduction 1.1. The 2005 Order establishes the Limits of Deviation (LoD) for taking the Midland Metro from the end of the section currently being constructed (west end of Stephenson Street) to the east end of Broad Street, via Pinfold Street, Victoria Square, Paradise Street and the south west side of Paradise Circus Queensway (PCQ). This is known as the Centenary Square extension (CSQ). The draft 2014 Order is for a variation to the 2005 Order LoD around PCQ and to renew the expired 2005 Order Compulsory Purchase Orders (CPO). As an objector to the 2014 Order, Victoria Square House has suggested that an alternative route, via Navigation Street and Suffolk Street Queensway is considered This note: a. Shows the layout of the Navigation Street bridges (appendix A). b. Lists the key elements of the four structures along Navigation Street (spans 2a, 2, 2b and 2c) in appendix B. c. Summarises the results of bridge assessments (appendix C). d. Shows the position of the elements of bridge span 2c with the assessed capacity. Gavin Last

2 Appendix A: Bridge Layout

3 Appendix B: Bridge Type Bridge 2a Structure Deck Abutment / Piers Parapets Comments 100 M type precast prestressed East Brick Brick parapets Assumed 1960 s concrete beams at West Brick / concrete structure a skew of 0 o, to the trestle. abutments. Reference Bridgeguard 3 Bridge Assessment: Navigation St Overbridge Birmingham; Bridge Number 2 (Assessment Report August 2004) 2 2 riveted steel parapet girders and 15 no. cross girders at a skew of Concrete slab spans between the cross girders. Parapet girders sit on rocker bearings on concrete pads at each end, cast on top of brick piers. The roadside faces of the main girders are infilled with brick. The remaining steelwork is encased in a thin layer of concrete. Assumed 1940 s structure Bridgeguard 3 Bridge Assessment: Navigation St Overbridge Birmingham; Bridge Number 2 (Assessment Report August 2004) 2b 47 post-tensioned concrete beams (southern portion of the deck) 22 concrete-encased steel beams forming the northern portion of the deck. The beams are topped with an in situ concrete slab. The northernmost 14 steel beams span onto an edge girder. The remaining beams are supported on a brick pier at the east end and a concrete trestle at the west end. North parapet is of concrete with an exposed aggregate finish. The southern parapet comprises 2 lengths of brick wall. The piers supporting the deck are not parallel resulting in the beams becoming shorter from south to north. Bridgeguard 3 Bridge Assessment: Navigation St Overbridge Birmingham; Bridge Number 2 (Assessment Report August 2004) Gifford Grillage Analysis of Span 2b c Northern edge of the deck comprises 12 concreteencased steel beams; the outer 5 of which span onto Brick abutments to the south. Concrete trestle pier to the north. The box girder forms the parapet on the south side. The north parapet is The piers and abutment supporting the deck are not parallel resulting in the beams becoming Gifford - Navigations Street Grillage 2C Report (2007)

4 Bridge Structure Deck Abutment / Piers Parapets an edge girder. Central part 69 inverted T precast, pre-stressed concrete beams. concrete with an exposed concrete finish. Comments shorter from north to south. Reference Southern part posttensioned segmental concrete box girder edge beam (5m deep) with 39 post-stressed concrete beams and 14 reinforced rectangular precast concrete units spanning between the girder and the west abutment. The remaining beams rest on a concrete trestle pier (east end) and a concrete cill beam on the brick abutment at the west end. The internal beams are topped with an in-situ concrete deck.

5 Appendix C: Results of Bridge Assessment E1 Bridge 2a Bridge Element Live Load Capacity Comments Report 2a Pre-stressed concrete beams 40 tonnes ALL Bridgeguard 3 Bridge Assessment: Navigation St Overbridge Birmingham; Bridge Number 2 (Assessment Report August 2004) Pre-stressed beams 30 units HB HB Assessment of Span 2A (March 2007)

6 E2 Bridge 2 Element Live Load Capacity Comments Report Edge Girders (carriageway) Edge Girders (footway) 40 tonnes ALL Limited to less than dead load by the bearing stiffeners (see 2007 reassessment). 40 tonnes AWL Limited to less than dead load by the bearing stiffeners (see 2007 reassessment). 40 tonnes ALL Bridgeguard 3 Bridge Assessment: Navigation St Overbridge Birmingham; Bridge Number 2 (Assessment Report August 2004) Cross Girders (carriageway) Cross Girders 40 tonnes AWL (footway) Concrete Slab Bearing stiffeners 40 tonnes Gifford Report March 2007, ref: 13806/FS/HB/RBS2/2/01 Masonry Abutments - No defects were noted which were considered to have an effect on the live load capacity of the structure provided no significant increases in load are envisaged. Gifford report - Bridgeguard 3 Bridge Assessment: Navigation St Overbridge Birmingham; Bridge Number 2 (Assessment Report August 2004)

7 E3 Bridge 2b The following extracts are from the Executive Summary of the Gifford report Grillage Analysis of Span 2B, ref 13806/FS/GR/RBS2/2B/01, dated June 2007.

8 E4 Bridge 2c The following extracts are from the Executive Summary of the Ramboll report Navigation Street Span 2C Restricted Loading Assessment, ref /2C/RLA/01/-, dated 15 March 2013.

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11 Appendix D: Bridge Span 2C