albrecht mueller, lend lease: st helena tunnel, pacific highway upgrade

ST HELENA TUNNEL T2E Pacific Highway Upgrade From Tintenbar to Ewingsdale

12th AUSTRALIAN TUNNELLING CONFERENCE 2013 Presented by: Albrecht Mueller

St Helena Tunnel T2E

CONTENTS

1. Project Overview 2. Progress 3. Geology 4. Excavation and Temporary Support 5. Permanent Support 6. Waterproofing

T2E St Helena Tunnel

Project Overview


Project Location 4

St Helena Tunnel T2E Project Key Data

16.3km of Dual Carriageway

10km of Access Roads

9 Bridge Structures / 3 Underpasses / 2 Culverts

3,200,000 m3 Bulk Earthworks

434m long tunnel through St Helena Hill

5


Location of St Helena Tunnel 6

Existing Highway

South Portal

North Portal

Upgraded Highway

St Helena Road


View from St Helena Hill to Byron Bay 7

Existing Highway

Byron Bay

St Helena Tunnel T2E Tunnel Key Data

Road tunnel: 2 tubes 3 lanes each (future consideration)

Length of tunnels: 2 x 434m

Cut and Cover Sections at each end 2 x 39m

Spacing of egress cross passages: 120m

Area of tunnel cross section: 210m2

Excavated volume: 150,000m3

8


Tunnel Cross Section: Size Compared to Previous Projects 9

M5 East (55 m2)

CLEM 7 (120 m2)

St Helena (210 m2)


Progress


Tunnel Progress: Heading 11

South Portal

North Portal


Northbound Tunnel from South: Heading and Bench Excavation 12


Tunnel Control Centre: Excavation for Deluge Tanks 13


Assembly of Tunnel Formwork 14


Geology


Regional Geology: Typical Basalt Columns (Fingal Heads) 16


Regional Geology: Typical Basalt Columns (Byron Bay Quarry) 17


Tunnel Geology: Long Section, Northbound Tube 18

Deep Zone of Extreme Weathering

Altered, Formerly Weathered Zones and

Deposits

Basalt


Tunnel Geology: Cross Sections 19

South and Central Section North Section


Tunnel Geology: Basalt Layers, South 20


Tunnel Geology: Basalt Layers, South 21


Tunnel Geology: Weathered Rock over Basalt Layers, North 22


Excavation and Temporary Support


Drill and Blast: Charged Face 24


Drill and Blast: Blast 25


Drill and Blast: Muck Pile 26


Excavator / Rock Hammer 27


Temporary Support: Support Types 28


Temporary Support: Support Type Selection 29


Temporary Support: Rock Bolts 30


Temporary Support: Shotcrete 31


Temporary Support: Lattice Girders 32


Temporary Support: Spiling Bars 33


Temporary Support: Face Nails 34


Permanent Support


Permanent Lining: View from Northern Portal 36


Permanent Lining: 500 – 800 mm Cast in Situ Concrete 37


Permanent Lining Reinforcement (Not T2E) 38


Permanent Lining Formwork (Not T2E) 39


Final Lining: Completed Tunnel 40


Waterproofing


Tunnel Hydrogeology: Long Section, Northbound Tube 42

Upper Water Level

Lower Water Level


Spring Feeding a Dam at the Northern Portal 43

Spring


Water Inflows during Excavation 44


Waterproofing: Waterproofing Membrane (not T2E) 45


Thank you for your attention.

Any Questions?

46

albrecht mueller, lend lease: st helena tunnel, pacific highway upgrade

Technology

st helena tunnel t2e

st helena tunnel t2edrill

st helena tunnel t2esouth

st helena tunnel t2eexcavation

st helena tunnel t2eprogress

st helena tunnel t2egeology

st helena hill5

st helena tunnel t2e