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Soft ground

University Link - Execution

Service Performed
Site supervision services, consulting and monitoring.
Commencement - Services
December 01, 2011
Completion - Services
August 01, 2012
Location
401 S. Jackson Street
Seattle, WA 98104
United States
Geology description

The geology along the alignment consists of over-consolidated glacial clay and till with fractured zones, as well as sand and silt layers.

Geology types
Soft ground
Description

University Link is a 5km light rail extension that runs in twin-bored tunnels from Downtown Seattle north to the University of Washington, with stations at Capitol Hill and on the University of Washington campus. The project further includes 20 cross passages located in soft ground and a maximum design water head of 60m. To deal with the prevailing geological conditions, specific ground support categories were developed. Steel fiber reinforced initial lining, sheet membrane waterproofing and CIP final lining were utilised.

Activity
Construction methods
Cross passage excavation
Propping of TBM tunnel at cross passage
Probe drilling at cross passage
Finished cross passage
Project number
262E
Final cost
$1.6 billion USD

University Link - Design

Service Performed
Sub-consultant for NATM/SEM design and waterproofing design.
Commencement - Services
July 02, 2007
Completion - Services
January 02, 2009
Location
401 S. Jackson Street
Seattle, WA 98104
United States
Geology description

The geology along the alignment consists of over-consolidated glacial clay and till with fractured zones, as well as sand and silt layers.

Geology types
Soft ground
Description

University Link is a 5km light rail extension that runs in twin-bored tunnels from Downtown Seattle north to the University of Washington, with stations at Capitol Hill and on the University of Washington campus. The twin-bored tunnels are connected with 20 cross passages. Dr. Sauer & Partners performed the temporary and final support design for the cross passages. This included the design of excavation and support measures and the development of specific ground support categories, settlement analyses, and the structural analyses of initial and permanent lining.

Activity
Construction methods
T Cross Passage
3D Finite Element Model
Project number
262D
Final cost
$1.6 billion USD

Crossrail C121 SCL Design CAT3 Check

Service Performed
Specialist sub-consultant for the analysis, design check, and design improvement recommendations of SCL structures.
Commencement - Services
January 01, 2011
Completion - Services
December 01, 2013
Location
25 Canada Square
London
E14 5LQ
United Kingdom
Geology description

The SCL tunnels are located in London Clay and Lambeth Group with overlying strata of terrace gravels and made ground.

Geology types
Soft ground
Description

Crossrail is a 118km railway line along an east-west route across London. Its central section runs via 21km twin-bore tunnels connecting eight underground stations and represents one of the world's largest infrastructure projects. Dr. Sauer & Partners was assigned to provide Category III independent design checking services on the Sprayed Concrete Lining works for the complete Whitechapel and Fisher Street SCL structures. Additional 3D non-linear FEA and assessments were carried out for the wraparound and junction structures of the Liverpool St Station and the Bond St Station.

Activity
Construction methods
Tunneling under
FEM results of binocular structure at Fisher Street Crossover
Fisher Street Crossover under construction
Project number
222C2
Final cost
£16 billion GBP

Tel Aviv Metro - Red Line

Service Performed
Dr. Sauer & Partners provides services as Checking Engineer for the design of all underground tunnels (NATM & TBM) and Cut and Cover structures.
Commencement - Services
April 01, 2011
Location
26 Harokmin St.
Tel Aviv
Israel
Geology description

The geology comprises predominantly sand and cemented dune sands called Kurkar, but also clay.

Geology types
Soft ground
Description

The Red Line will link the most congested areas of the city of Tel Aviv, operating along 24km and serving 34 stations. The light rail trains will run above ground as well as through a tunnel section of 11km length, connecting ten underground stations. Excavation of the twin tube tunnels will be undertaken by TBMs. The tunnels will be connected by cross passages spaced at a maximum distance of 250m. Station boxes will be constructed using diaphragm walls and piles. The Red Line should start its operation by 2021 and transport 70 million passengers per year.

Activity
Final cost
$300,000,000
Construction methods
Tunneling under
Route map (www.nta.co.il/en/line/73)
Galei Gil Shaft to be used to launch TBMs
Project number
362C1
Final cost
$3 billion USD
Completion date
Ongoing

Edmonton Light Rail

Client
Service Performed
Dr. Sauer and Partners provided construction support services and supervision of the excavation of the Light Rail Tunnels, which were constructed using NATM.
Commencement - Services
August 01, 2011
Completion - Services
January 01, 2013
Location
1 Sir Winston Churchill Sq NW
Edmonton, AB T5J 2R7
Canada
Geology description

Glacially controlled terrain comprising clay, silt and sand deposits underlain by Mesozoic bedrock consisting of sandstone and shale.

Geology types
Soft ground
Description

The City of Edmonton built a 3.3km Light Rail Train extension from Churchill Station to the Northern Alberta Institute of Technology. Approximately 670m of the extension are underground consisting of ca. 430m of twin tunnels of 6m nominal diameter. NATM/SEM tunneling was applied. The software 2DOC, which was at that point used in North America for the first time, allowed real-time tracking of all geotechnical instruments on the project, as well as the recording of the actual geotechnical conditions and the grout support elements installed.

Activity
Final cost
$300,000,000
Construction methods
Tunneling under
Excavation under way
Tunnel face
Project number
437E
Final cost
$300 million CAD

Eglinton Crosstown LRT

Owner
Service Performed
Preliminary and final SEM tunnel design.
Commencement - Services
November 01, 2015
Location
97 Front Street West
Toronto, ON M5J1E6
Canada
Geology description

Glacial depositional systems created a complex distribution of heavily overconsolidated till layers, separated by interstadial stratified deposits of glaciolacustrine clay, silt, and sand.

Geology types
Soft ground
Description

The Crosstown is a light rail transit line, which is part of the regional transportation plan for the Greater Toronto and Hamilton Area. The project will provide a 19km corridor across Eglinton Avenue, connecting ten stops at grade and 15 stations with a 10km twin-bored tunnel. Dr Sauer & Partners provided detailed design for Oakwood, Avenue, Laird and Leaside stations. A combination of Cut-and-Cover construction for the shafts and mined techniques (SEM) for the tunnels will be utilised. Finite element analyses were carried out to determine structure capacity of linings and trigger values.

Activity
Construction methods
Tunneling under
Route map (www.thecrosstown.ca)
Toronto transit map (www.thecrosstown.ca)
Project number
467D
Final cost
$4.9 billion CAD
Completion date
Ongoing

Silverline Phase III

Service Performed
Sub-consultant for NATM design.
Commencement - Services
January 01, 2003
Completion - Services
January 01, 2008
Location
500 Arborway
Boston, MA 02130
United States
Geology description

Made ground, peat, glacial till (cohesive, plastic), Boston Blue Clay and sand.

Geology types
Soft ground
Description

Silver Line Phase III is an underground extension of the Silver Line from the current terminal at South Station into Downtown Boston. The tunnels through Boston's Chinatown lie up to 25m below surface and include ca. 1400m long-running tunnels, two stations and complex underground junctions. The NATM design alternatives for LRT / Busway tunnels are located beneath existing subway stations and running tunnels. 3D modelling tools were utilised to create multiple alignments.

Activity
Final cost
$550,000,000
Construction methods
Tunneling under
3D rendering of the Silverline Phase III alignment
NATM alternative beneath MTA's Chinatown Station
Project number
347D1
Final cost
$550 million USD

Holborn Station Capacity Upgrade

Client
Service Performed
Feasibility study and conceptual design.
Commencement - Services
April 01, 2014
Location
Kingsway
London
WC2B 6AA
United Kingdom
Geology description

London Clay and Lambeth Group formation, which may contain water-bearing sand channels.

Geology types
Soft ground
Description

Holborn is a LU station in central London. It is served by the Central and Piccadilly lines. Demand for both lines at Holborn is high. The principal design challenges are the close proximity of the proposed tunnels to existing operational tunnels, complex tunnel geometry and alignments, limited clearance to existing buildings, restricted work sites and strict settlement criteria. The lining system is a double shell lining with both linings considered part of the permanent load bearing structure.

Activity
Final cost
$150,000,000
Construction methods
Tunneling under
3D visualisation of existing Holborn underground station
Archive photo of heading of escalator tunnel (1931)
Project number
471C
Final cost
£150 million GBP
Completion date
Ongoing

Crossrail 2

Client
Service Performed
Provide SCL project services, supporting main tunnel-stations-alignment workstreams, design of tunnel cross sections, SCL design principles, geotechnical review and risk assessment.
Commencement - Services
January 01, 2015
Location
22 Carlisle Place
London
SW1P1JA
United Kingdom
Geology description

The geology is expected to be highly variable crossing most of the typical units of the London basin (river terrace deposits, London Clay, Lambeth Group, Thanet Sand).

Geology types
Soft ground
Description

Crossrail 2 is a proposed new rail infrastructure project, aiming to alleviate further crowding and congestion across London. The proposed central route will provide a link between Wimbledon in the South and New Southgate and Tottenham Hale in the North with a provision for an Eastern branch towards Hackney Central. It will provide interchange with multiple London underground, London Overground, Crossrail 1, national and international rail services. It is expected to increase significantly the capacity of the regional rail network and reduce the journey times supporting the population growth of the City of London.

Activity
Construction methods
Tunneling under
Proposed route according to public consultation autumn 2015
Crossrail 2 in numbers (www.crossrail2.co.uk)
Project number
476C
Final cost
£30 billion GBP
Completion date
Ongoing

Crossrail Farringdon Station - Geotechnical Assessment

Service Performed
Temporary works design included design of tunnels prior to ring closure and 28 day strength as well as depressurisation design.
Commencement - Services
May 01, 2013
Completion - Services
October 01, 2015
Location
Cnr Charterhouse St & Farringdon Rd
London
EC1M3HN
United Kingdom
Geology description

Excavation encountered almost all the London basin units but mainly Lambeth Group, comprising stiff to very stiff overconsolidated clays to water bearing sand units.

Geology types
Soft ground
Description

The station is located in central London between Tottenham Court Road and Liverpool Street Crossrail (CRL) Stations. Constructed in the geologically most complex area in the whole of CRL, an optimised geotechnical and SCL tunnel design was implemented, which resulted in significant time and cost benefits for the project. Using a dynamic 3D geological model in conjunction with SCL tunnelling represented a key element of the geotechnical risk management framework.

Activity
Service areas
Construction methods
Special Construction techniques
Tunneling under
Groundwater control
Max Overburden
25 m
Max Excavation Area (m2)
95
Tunnel length
1000 m
Qualitative geotechnical risk mapping
Exerpt of the 3D finite element model
Project number
222D5
Min Overburden
5 m
Final cost
£300 million GBP

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