GEOMETRY CONTROL OF PRECAST SEGMENTAL BALANCED CANTILEVER BRIDGES ON THE HUNTER EXPRESSWAY

Transcription

1 GEOMETRY CONTROL OF PRECAST SEGMENTAL BALANCED CANTILEVER BRIDGES ON THE HUNTER EXPRESSWAY

2 Introduction Authors Jarrod Hitchcox Associate Technical Director Arcadis Australia Pacific Alliance Structural Design Representative Daniel Mueller Survey Manager CPB Contractors Senior Surveyor

3 Project Overview 40km of expressway M1 Motorway to Branxton Two contracts one D&C and one alliance Hunter Expressway Alliance (HEA) 13km from the M1 Motorway to Kurri Kurri through the Sugarloaf Mountains HEA partners Thiess Roads & Maritime Services Parsons Brinkerhoff Hyder Consulting (now Arcadis Australia Pacific)

4 Viaduct Bridge Design Three twin viaduct bridges (three, four and five span configurations) Maximum span of 75m End spans varying from 52m to 60m Haunched superstructure varying from 3.0m to 4.2m deep Free and guided bearings Fixed and guided shear keys Precast pier segments Pile caps and bored piles

5 Proposed Construction Sequence Self launching overhead erection gantry

6 Proposed Construction Sequence Self launching overhead erection gantry 12 segments per span Six to eight backspan segments supported by gantry

7 Geometry Control Report Key design assumptions Relative humidity: 61% Average temperature: 18 C Characteristic compressive strength of concrete: 65MPa Elastic modulus of concrete: 35,600MPa Age of deck segments at erection: 28 days End span construction period: Four days

8 Design Changes Mine subsidence Geotechnical investigations during pile boring Adjusted shear planes

9 Design Changes Mine subsidence Geotechnical investigations during pile boring Adjusted shear planes

10 Design Changes Mine subsidence Geotechnical investigations during pile boring Adjusted shear planes

11 Construction Sequence Changes Segment release timing

12 Construction Sequence Changes Segment release timing Key segment support From support from the gantry

13 Construction Sequence Changes Segment release timing Key segment support From support from the gantry To support from the cantilever tip

14 Construction Sequence Changes Segment release timing Key segment support From support from the gantry To support from the cantilever tip

15 Construction Sequence Changes Segment release timing Key segment support From support from the gantry To support from the cantilever tip Construction loadings

16 Construction Sequence Changes Segment release timing Key segment support From support from the gantry To support from the cantilever tip Construction loadings Program accelerations

17 Construction Sequence Changes Segment release timing Key segment support From support from the gantry To support from the cantilever tip Construction loadings Program accelerations

18 Site Changes Superstructure stressing

19 Site Changes Superstructure stressing Temperature

20 Site Adjustment Mechanisms Vertical geometry Segment shims

21 Site Adjustment Mechanisms Vertical geometry Segment shims Counterweights

22 Site Adjustment Mechanisms Vertical geometry Segment shims Counterweights Nailing tendon

23 Site Adjustment Mechanisms Vertical geometry Segment shims Counterweights Nailing tendon Abutment segment jacking

24 Site Adjustment Mechanisms Vertical geometry Segment shims Counterweights Nailing tendon Abutment segment jacking

25 Site Adjustment Mechanisms Vertical geometry Segment shims Counterweights Nailing tendon Abutment segment jacking Pier segment rotation

26 Site Adjustment Mechanisms Vertical geometry Segment shims Counterweights Nailing tendon Abutment segment jacking Pier segment rotation

27 Site Adjustment Mechanisms Longitudinal geometry Abutment segment size and position

28 Site Adjustment Mechanisms Longitudinal geometry Abutment segment size and position Span closure pours

29 Finishing Works Surfacing and approach slabs Concrete barriers

30 Finishing Works Surfacing and approach slabs Concrete barriers Barrier railings

31 Finishing Works Surfacing and approach slabs Concrete barriers Barrier railings Drainage

32 Finishing Works Surfacing and approach slabs Concrete barriers Barrier railings Drainage

33 Finishing Works Surfacing and approach slabs Concrete barriers Barrier railings Drainage Expansion joints

34 Design Recommendations Site investigations Geometry control in design team s scope of works Material variability Construction options Additional capacity Stressing cantilever, continuity and external Bearing and joint movement Bearing rotation Strength Allowable tolerances Structural Other disciplines Design adjustment options

35 Delivery Recommendations Setting of design parameters Alliance or ECI Survey and timely reporting Site design presence Site adjustment options

36 GEOMETRY CONTROL OF PRECAST SEGMENTAL BALANCED CANTILEVER BRIDGES ON THE HUNTER EXPRESSWAY Questions