AGENDA AGENDA. Route 15/29 SBL Bridge Superstructure Replacement & Widening. NOVA District. Bridge Views SCOPE. Existing Structure.

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1 Route 15/29 SBL Bridge Superstructure Replacement & Widening Existing Structure Scope Accelerated Procedure Staging (Superstructure) Preparatory Work (Substructure) NOVA District Questions EXISTING STRUCTURE Span 1 Span 2 Span 3 Location: Route 15/29 SB Bridge over Broad Run, Prince William County Superstructure: 3-Span, Concrete T beam, Simply Supported Substructure: Wall Type Piers & Abutments Year Built: 1952 Condition in 2005: Severe Deterioration of Superstructure Bridge Elevation Bridge Views SCOPE Profile View Replace & Widen Superstructure Minimize Traffic Disturbance Approach Roadway View at only Maintain 1 Lane of Traffic at Restore Traffic to Normal (2 Lanes) at Complete Work in 12 s 1

2 Existing & Proposed Bridge Width Existing Bridge Exterior Edge ½ 2-6½ 28-0 curb-to-curb Median 5-4 Widening Proposed Bridge Rail 36-0 face-to-face of rails 1-3 Rail Shld Rdwy Rdwy Shld (Looking North, Station Ahead) & Elevation ACCELERATED CONSTRUCTION PROCEDURE (MODULAR CONSTRUCTION) 1. Preparatory Work - Maintain all s - Widen Approaches - Modify Substructure for Modular Superstructure 2. Superstructure Replacement - Maintain 1 Lane of Traffic at - Remove Designated Portions of Superstructure - Replace with Modular Segments - Restore traffic to Normal (2 Lanes) at - Accomplish Work in 12 s 3. Overlay the Bridge and Approaches PROPOSED MODULAR STRUCTURE Module Configuration: Each Module Consists of a Prefabricated Conc. Deck on Two Steel Beams Module Width Arrangement in Transverse Section: (12-11 ) (9-0 ) (8-9 ) (7-10 ) Module Length = Span Length (~ 44 ) Max. Module Weight = ~35 tons (~30 tons w/ Lightweight Concrete) Longitudinal Joints between Modules: Grouted/Waterproofed Keyways Diaphragms between Modules: Field Installed Steel Diaphragms Deck Parapets: t Cast Concrete Module Width Stage Sequence of -I 2

3 Stage Stage Stage Sequence of - II Stage Stage 3

4 Broad Run Legend: Rte 15/29 SB Traffic Rte 15/29 NB Traffic N Rte 15/29 SB Traffic Existing Median Crossover 400 South of Bridge Broad Run SB 15/29 Bridge Under Median Existing Median Crossover 300 North of Bridge Rte 15/29 NB Traffic Stage II MOT for time 1. Close the SB bridge to traffic from 9:00 p.m. to 5:00 a.m. 2. Route the SB traffic on NB via the crossover 300 north of the bridge. 3. Route the SB traffic back on SB via the crossover 400 south of the bridge 4. Maintain both lanes of traffic on SB bridge from 5:00 a.m. to 9:00 p.m. Sequence of - III Transport Sequence of - III Transport lane 4

5 Stage IV Stage Sequence of -IV Stage IV Stage IV Stage Stage Completed Structure Railing 8 Shoulder 12 Traffic lane 12 Traffic lane Overlay not shown Median 1-3 Railing 36-0 Roadway 12 Lane 12 Lane Exterior Edge Shoulder time Operations Include; - Install Middle Diaphragms - Apply Rapid Set Joint Mortar 8-0 Shoulder 4 Shldr Concrete in Deck & Rail; - Light Weight Low Permeability ~12-11 ~9-0 ~8-9 ~7-10 Transverse Section 5

6 Concrete in Substructure; Low Permeability Abutment A Modifications (Repair & Removal) Abutment A Modifications (Widening & Beam Seat Reconstruction) Concrete in Substructure; Low Permeability Beam Seat Reconstruction (Self Consolidating Concrete) Backwall Removal & Modification (time Operation) Abutment Modifications Pier Modifications (Repair, Removal, Widening & Beam Seat Reconstruction) Beam Seat Reconstruction (Self Consolidating Concrete) Beam Seat Reconstruction & Encasement of Post-Tensioning (Self Consolidating Concrete) Pier Modifications 6