The Challenge of Urban Rail Infrastructure The Design of William Street Underground Station Barry Moore 23 rd November 2005 AusRAIL PLUS 2005

NMR City Project – Overview William Street Station – Facts and Figures Challenges Faced in Design - Design Elements - Major Constraints - Multi-Disciplinary Interfaces - Solutions Adopted Key Concepts for Design Delivery William Street Station 23 rd November 2005

Perth Yard Portal William Street Station Esplanade Station Cut and Cover / Dive Structures Bored Tunnel NMR City Project - Overview 23 rd November 2005

NMR City Project - Overview Client: Public Transport Authority (PTA) Main Contractor: Leighton Kumagai Joint Venture (LKJV) Principal Consultant: Maunsell Australia Pty Ltd Architects: Hassell Spowers Joint Venture (HSJV) Electrical and Mechanical: Alstom Australia 23 rd November 2005

William Street Station - Facts and Figures 138m long station box 29m wide at the northern end Track level 17m below ground 27,000m 3 of concrete 4,000 tonnes of reinforcement 70,000m 3 of excavation “Top Down” construction During operation – 16 Trains per peak hour (in each direction) – 50,000 passengers per day 23 rd November 2005

Challenges Faced in Design Design Elements Major Constraints Multi-Disciplinary Interfaces Solutions Adopted 23 rd November 2005

Design Elements 4. Excavate to concourse 6. Excavate to base 11. Backfill 3. Roof 5. Concourse 9. Column encasement 1. Diaphragm walls 7. Base and track slab 12. Operational 10. Platform/ internal structure 2. Barrette & plunge columns 8. Minipiles Construction Stages

Major Constraints 23 rd November 2005 Location and Position - Existing roads, buildings and services - Future development

Wellington Building William Street Station - Constraints 23 rd November 2005 (Copyright HSJV. Concept.)

Major Constraints 23 rd November 2005 Location and Position - Existing roads, buildings and services - Future development Wellington Building - Design of Underpinning - Support during excavation - Control of movement and deflections

The Wellington Building 23 rd November 2005

Major Constraints 23 rd November 2005 Location and Position - Existing roads, buildings and services - Future development Wellington Building - Design of Underpinning - Support during excavation - Control of movement and deflections Noise and Vibration - During construction - During operation Tunnel Boring Machine (TBM) - Traversing and launching from the station - “Soft Eye” to allow breakthrough - Interface between bored tunnel and station

23 rd November 2005 Tunnel Boring Machine (TBM) (Copyright LKJV.)

Multi-Disciplinary Interfaces 23 rd November 2005 Rail - Rail alignment and level - Transit space Architecture - Station concept - Space and light - Passenger flows

Concourse Level 23 rd November 2005 (Copyright HSJV. Concept.)

Platform Level 23 rd November 2005 (Copyright HSJV. Concept.)

Multi-Disciplinary Interfaces 23 rd November 2005 Rail - Rail alignment and level - Transit space Architecture - Station concept - Space and light - Passenger flows Electrical and Mechanical - Tunnel ventilation - Room sizes - Lighting, HV and LV supply, communications, fire services

23 rd November 2005 Station Plant Rooms

Solutions Adopted 23 rd November 2005 Diaphragm Wall Design Underpinning Design Concourse Design

23 rd November 2005 Diaphragm Wall Design Typical panels 30m long x 6.4m wide x 1m thick Toe level 11m below base slab level Supports the excavation during construction - Minimal noise and vibration compared to sheet piling - Can be installed within 1m-2m of existing buildings - GFRP reinforcement used at headwalls to allow breakthrough of TBM Forms the station box when operational - Designed for future development over and next to the station - Designed to withstand a 1 in 2000 year seismic event

23 rd November 2005 Diaphragm Walls

23 rd November 2005 Underpinning Design Minipiles supporting building and station roof installed from basement of existing building New station roof slab constructed in basement of existing building 5000t building load transferred from existing foundations onto new roof slab Deflections controlled during excavation using flatjacks Any damage to building to be limited to “very slight”

23 rd November 2005 Underpinning

23 rd November 2005 Concourse Design Concourse required for station layout and operation Also acts as a permanent prop to the diaphragm walls 600mm thick Critical part of architectural concept 27m long central void propped with massive steel sections Design force of 17,000kN with a moment of 1,600kNm

Concourse 23 rd November 2005

Key Concepts for Design Delivery 23 rd November 2005 Positive relationship with client Appreciation of multi-disciplinary relationships Close collaboration with construction team Design team based on site Creativity

NMR City Project – Overview Facts and Figures Challenges Faced in Design - Design Elements - Major Constraints - Multi-Disciplinary Interfaces - Solutions Adopted Key Concepts for Design Delivery William Street Station 23 rd November 2005

The Challenge of Urban Rail Infrastructure The Design of William Street Underground Station Barry Moore Senior Engineer – Rail Maunsell Australia Pty Ltd 629 Newcastle Street, PO Box 81, Leederville, WA 6902 Tel: (08) (LKJV Project Office) 23 rd November 2005