On Line Widening of the N7 Naas Road Integrating Design and Construction Scheme Description and Background Tender Design Priorities Integrated Program

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1 On Line Widening of the N7 Naas Road Integrating Design and Construction Presentation By Jim Thorpe BSc, Dipl Eng, CEng, MIEI, MICE Project Manager Roughan & O Donovan Faber Maunsell Alliance Contractor s Designer for Clonmel -Laing O Rourke JV

2 On Line Widening of the N7 Naas Road Integrating Design and Construction Scheme Description and Background Tender Design Priorities Integrated Programming Integrating Pavement and Alignment Integrating Structures into Construction Planning Discussion

3 Scheme Description 14km of N7 widened from dual 2 to dual 3 from Rathcoole to Maudlins 4 new grade separated junctions, Johnstown,Kill, Castlewarden and Steelstown Maudlins and Rathcoole junctions upgraded 14km new side road and interchange links 2 Footbridges, 12 Culverts, 17 Sign Gantries New Streetscapes and Traffic Calming in Johnstown and Kill villages

4 Background Originally two separate schemes: Kildare County Council High quality dual with local access segregated on parallel local roads Statutory Approval 2002 South Dublin - Halcrow Barry All purpose road with left in left out local road junctions and private accesses Statutory Approval 2003

5 Kildare South Dublin

6 Design and Build Contract Merged into single D+B scheme August 2003 with tenders submitted in April 2004 Scheme to maintain a flow of 62,000 vehicle per day through the site Lowest Comparative Tender won by CELOR taking account of Site Occupation and Lane Rental charges Maintain 2 lanes in each direction and minimise hard shoulder closures Pre-tender Programme of 30 months reduced to 22 months in CELOR tender

7 Tender Design Priorities Maximise re-use of existing pavement construction Minimise volume of materials to be transported through congested site Minimise excavation Minimise utility diversions Minimise culvert construction under mainline Integrate traffic management phasing into alignment design Optimise Construction Programme

8 Tender Design Approach Realign horizontally to maximise re-use of pavement Maudlins Junction

9 Tender Design Approach Realign Vertically, initially to a nominal 200mm above existing pavement Specimen Design Tender Design

10 Tender Design Approach Refine horizontal alignment to facilitate traffic management

11 Tender Design Approach Design Interchanges to permit temporary diversion of the N7 flows Alignments through roundabouts Widths and pavements of link roads

12 Tender Design Approach Re-Design of Castlewarden Interchange as Compact, with straight Bridge

13 Programme Integration Design and Construction Process Mapping Cross team understanding of roles and interfaces, Eg:- Precast culvert procurement Requires early sizing Requires critical approvals Requires detailed topographic survey Requires early traffic management and procurement

14 Programme Integration Process Programming g Ideal world Integration of Design and Construction Programmes Interchanges early for TM Mainline priorities to match TM Priority Structures Pi Priorities ii for Topo Survey

15 Programme Integration Revised Construction Programme Trade Construction float ease design peaks Delay construction start until design lead established Thereby minimise site possession and traffic disruption

16 Programme Integration Resource Balancing Resource loading by discipline Identify unrealistic peaks Breakdown into smaller elements Re-programme to address more specific priorities Re-alignment - reduce traffic switches to free programme constraint

17 Project Flow Programme Integration Weekly team meetings between Design and construction team leaders Review progress and commit to the next week s programme - at micro level of agreed process map Clear and immediate understanding of effects of delays - full team buy in to overcoming these together Similar procedures followed on site on a daily basis to plan and manage construction

18 Programme Integration

19 Integrated Pavement and Alignment Existing Pavements Kildare section fully flexible South Dublin rigid concrete with thin bituminous overlay Rathcoole Interchange recently upgraded by slab stabilisation and major overlay Construction Requirements Concrete slabs to be removed Rathcoole - replace wearing course

20 Integrated Pavement and Alignment Surveys Detailed Level Survey Full video condition survey Full Radar Survey Calibration cores Falling Weight Deflectometer Initial Design Analytical l design of minimum i overlay requirements by chainage for each lane

21 Integrated Pavement and Alignment Vertical Alignment Optimisation Seek to match minimum pavement depths Rationalise pavement types to suit

22 Rubblising of Concrete Pavement Crack and Seat as sub-base base rejected Rubblising with controlled breaker Plate load tests to prove foundation Saves removal and capping

23 Integrating Structures into Construction Culverts Detailed Condition Surveys Sophisticated analysis to maximise re-use of existing structures New culverts precast for speed Re-alignment to keep square to traffic lanes to align joints with TM phases

24 Integrating Structures into Construction Footbridges Requirement for single span One night closure for lift Specimen and Tender designs in Steel Additional gantries put pressure on steel fabricators - Precast Concrete

25 Integrating Structures into Construction Footbridges Longest beams to date at 43m Heaviest Lift with deck and parapets

26 Integrating Structures into Construction Overbridges Bank Seats on Spread Footings Special fill achieves 1:1.5 slope Standardise spans to suit Precast Beams

27 Integrating Structures into Construction Overbridges Designed as lost diaphragms Beams supported on Temporary Trestles

28 Integrating Structures into Construction Overbridges Temporary Works Failure on M1 Dundalk Introduced Landing shelf Sound base within original design envelope Plus propping

29 On Line Widening of the N7 Naas Road Summary Integrating Design and Construction Complex scheme with critical live traffic Aligned to minimise time and materials within TM Integrated Programming to minimise on site time Refined pavement and alignment design Structures designed to integrate with construction programme and Traffic Management QUESTIONS?

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