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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

Sound Transit Beacon Hill Station

Service Performed
Optimizing station and tunnel configurations, Interpreting geologic information, preliminary and detailed design, developing 3D Finite Element Models and performing structural and seismic design.
Commencement - Services
January 01, 2002
Completion - Services
January 01, 2009
Location
401 S. Jackson Street
Seattle, WA 98104
United States
Geology description

Beacon Hill Station is located 49 m below the ground surface in complex glacial soils with multiple groundwater horizons.

Geology types
Soft ground
Description

Beacon Hill Station is part of the 22.5 km initial segment of Sound Transit's Central Link Light Rail. It is located 49 m below the ground surface in complex glacial soils with multiple groundwater horizons. The project comprises deep mined station tunnels and two 1.5 km long running tunnels excavated using a tunnel boring machine. The mined station was excavated through compressible glacial soils with multiple groundwater horizons using conventional mining techniques. The access shafts and station headhouses were constructed using slurry walls and cut-and-cover techniques.

Activity
Construction methods
Special Construction techniques
Tunneling under
Tunnel length
1.5km
Beacon Hill Station Layout
Tunnel Excavation under way
Project number
418C
Final cost
$250 million USD

Ottawa Light Rail Transit - Design

Service Performed
Tender design, preliminary and full detailed design including execution drawings for the mined twin track running tunnel, three mined station caverns and access shafts.
Commencement - Services
March 01, 2012
Completion - Services
July 01, 2019
Location
529 Albert St
Ottawa, ON K1R 7Z0
Canada
Geology description

The geology varied between competent limestone and fractured shale. A soft ground section included variable glacial till deposits of sand, silt and clay layers and a groundwater table close to ground surface.

Geology types
Hard rock, Soft ground
Description

Ottawa's Confederation Line runs from Tunney's Pasture in the west to Blair station in the east, is 12.5 km long and includes 15 stations. The central piece is a 2.5 km long tunnel, running under the central business district of the city, including 3 underground stations. The twin track running tunnel and 3 underground stations were designed using the mined construction method in order to minimise surface disruption. The underground stations are located adjacent to existing, sensitive and historic buildings and required detailed risk mitigation measures during design. An innovative engineering solution involving a tailor-made excavation sequence and permanent tension ties spanning the cavern was developed.

Activity
Construction methods
Tunneling under
Tunnel length
2.5km
Downtown station located between high-rise buildings
Downtown station construction sequencing including tie-backs
Cavern construction under way
Mined Caverns directly adjacent to existing basements
Special Excavation Sequences incorporating pre-tensioning
Large-Scale 3D Numerical Modelling incorporating the surroundings
Project number
123D
Final cost
$2.1 billion CAD
Completion date
Ongoing

Green Park Station Upgrade

Service Performed
Tunnel and shaft design, construction support during excavation and primary lining works.
Commencement - Services
January 01, 2009
Completion - Services
May 01, 2010
Location
Piccadilly
London
W1J 7BX
United Kingdom
Technical data

Provide Step Free Access between street level and Northern, Piccadilly & Jubilee line platforms via a new ticket hall and lift system. The station, with an estimated annual use of 25 million, will thus become accessible for passengers with disabilities and reduced mobility.

Geology description

London Clay formation

Geology types
Soft ground
Description

Green Park tube station is a LU station situated on the north side of Green Park in central London. The station serves as an interchange between the Piccadilly, Victoria and Jubilee lines. As part of Transport for London's (TfL) investment programme, LU is implementing capacity enhancement and step‐free access (SFA) works to various stations. Dr. Sauer & Partners was responsible for the design of the primary support, i.e. sprayed concrete lining (SCL) and for providing construction support services including supervision of the excavation works and installation of the primary lining.

Activity
Final cost
$9,000,000
Construction methods
Tunneling under
Max Overburden
10m
Proposed structures
Secondary lining works in the upper shaft
Project number
423
Final cost
£9 million GBP

Bond Street Station Upgrade Execution

Service Performed
Design of SCL tunnels and access shafts linked to Central, Jubilee line, and Crossrail Link Passage. Construction supervision.
Commencement - Services
June 01, 2013
Completion - Services
May 01, 2016
Location
Oxford Street
London
W1C 2HU
United Kingdom
Geology description

London Clay

Geology types
Soft ground
Description

Bond Street Station serves an interchange between the Jubilee Line, the Central Line and the future Crossrail Station. New tunnels including access and lift shafts, construction adits, binocular cross passage tunnels, large concourse and connection chambers, underpass and over-bridge tunnels cutting through existing platform tunnels, and an inclined escalator tunnel were constructed in very close proximity to existing London Underground structures.

Activity
Tunneling under
Max Overburden
10-50m
Max Excavation Area (m2)
25-55m2
Excavation connection chamber
Secondary lining escalator tunnel
SCL spray of Connection Chamber
SCL Access Tunnel
SCL Tunnel connecting to existing Cast Iron Passage Way
SCL Tunnel, Excavation of Escalator Tunnel
SCL Shaft, breakout for SCL tunnel
SCL Side Drift Tunnel
Project number
419E
Final cost
£150 million GBP

Bond Street Station Upgrade Design

Service Performed
Design of the primary and secondary sprayed concrete linings, 3D FE modelling of all SCL tunnels including excavation steps and ground movement assessments.
Commencement - Services
January 01, 2011
Completion - Services
January 01, 2013
Location
Oxford Street
London
W1C 2HU
United Kingdom
Geology description

The tunnel horizon is generally within the London Clay formation with the lowest tunnels sitting in the Lambeth Group, where clay layers and water bearing clayey sands are inter-changing.

Geology types
Soft ground
Description

Bond Street tube station is a major gateway to London's West End served by both the Central and Jubilee lines. As part of the LU tube upgrade plan, the station is undergoing a major upgrade to increase capacity, improve accessibility and create interchange with the new Crossrail station. The project provides two additional escalators from the interchange level to the Jubilee line, low-level interchange route between the Central and Jubilee lines, a new step-free entrance, ticket hall and new lifts. The majority of the tunnelling works will be mechanically excavated and lined with sprayed concrete.

Activity
Final cost
$150,000,000
Construction methods
Tunneling under
Max Excavation Area (m2)
15-90m2
Tunnel length
370m
3D view of proposed tunnelling and existing infrastructure
Connection chamber one
Graphic  showing split of 3D FE models
3D Graphic showing construction site and building frame used for laydown/plant
Northern Tunnels in relation to Jubilee Line platforms and Post Office Tunnel
Binocular Tunnel at Jubilee Platform level
Project number
419D1
Final cost
£150 million GBP

Tottenham Court Road Station Upgrade Execution

Client
Service Performed
Design of SCL tunnels and access shafts linked to both Central and Northern line. Supervision during construction.
Commencement - Services
March 01, 2011
Completion - Services
January 01, 2016
Location
Oxford Street
London
W1D 1AN
United Kingdom
Geology description

London Clay formation

Geology types
Soft ground
Description

The major upgrade to the LU Tottenham Court Road Station has been proposed to relieve congestion, achieve step-free access and modernise the station. The major elements of the station upgrade comprised a new enlarged sub-surface ticket hall, a fire-fighting access / emergency escape shaft linked to both Central and Northern lines, a triple escalator barrel, and concourses to the Northern and Central lines. In the latter concourse two new overbridges were included to lead to the platforms via new stairs and lifts. For the tunnelling works, a particularly challenging part was to design and construct the two SCL overbridges over the operational Central line.

Activity
Final cost
$480,000,000
Tunneling under
Max Overburden
10-20m
Max Excavation Area (m2)
23-104m2
Tunnel length
13-104m
SCL side drift tunnel
Aerial view of the construction site
Sprayed Waterproofing Membrane
SCL Crosspassage
SCL Tunnel, overbridging operational Central Line Tunnel
SCL Excavation through existing Structure
Project number
411E
Final cost
£480 million GBP

Tottenham Court Road Station Upgrade Design

Client
Service Performed
Design of numerous temporary sprayed concrete lined shaft and tunnel structures, and the waterproofing system for the upgrade of the existing London Underground Tottenham Court Road Station.
Commencement - Services
August 01, 2007
Completion - Services
January 01, 2010
Location
Oxford Street
London
London
W1D 1AN
United Kingdom
Technical data

Tottenham Court Road Station is a London Underground station situated in central London. The station serves as an interchange between the Central and Northern lines. Over 150,000 passengers use the station daily.

Geology description

London Clay Formation (over-consolidated, very stiff to hard clay)

Geology types
Soft ground
Description

Currently over 150,000 passengers use the station daily and with the completion of Crossrail in 2017, passenger numbers are expected to increase to over 200,000. The tunnels are of diameters between 4.0m and 11.0m and typically consist of a temporary sprayed concrete primary lining, a spray applied waterproofing membrane and a cast-in-place concrete secondary lining. Multiple transitions and interfaces to existing LU structures make for a challenging design and construction project under the busy streets of central London.

Activity
Final cost
$480,000,000
Construction methods
Special Construction techniques
Tunneling under
Max Excavation Area (m2)
23-104m2
Tunnel length
13-104m
Overview of new tunnel works
General arrangement of sprayed concrete overbridge
Northern line concourse tunnel with cross passages
Installation of steel transfer beam
Excavation and support of Northern line concourse tunnel
Removal of existing backfilled structure
Project number
411D
Final cost
£480 million GBP

Crossrail Eastern Running Tunnels

Service Performed
Shaft and tunnel design, engineering support, geotechnical engineering and site supervision services.
Commencement - Services
February 01, 2011
Completion - Services
December 01, 2012
Location
London
London
EC1M 6BY
United Kingdom
Geology description

Geological locations of the cross passages vary from London Clay to Lambeth Group and Thanet Sands.

Geology types
Soft ground
Description

Contract C305 is the biggest design-bid-build construction contract of the Crossrail (CRL) project and includes the eastern running tunnels of CRL's central section with launch shafts and SCL launch adits for TBMs at Limmo Peninsula, SCL caverns and launch adits for TBMs at Stepney Green and 10 SCL cross passages between the running tunnels with lengths up to 30m. At the Limmo Peninsula site a 40m deep and 30m diameter SCL shaft was built. At the shaft bottom in Stepney Green, two 30m long and up to 10m wide SCL launch adits were constructed followed by two 14m high and up to 18m wide, SCL caverns with single sidedrift and double sidedrift cross sections.

Activity
Construction methods
Max Excavation Area (m2)
50-130m2
Tunnel length
15m
Limmo Main Shaft
Limmo Auxiliary Shaft bottom
Platform Tunnel West - Excavation - TBM Tunnel Enlargement
3D Model Limmo Auxiliary Shaft
Limmo Shafts and Tunnel layout - left Auxiliary Shaft - right Main Shaft
Project number
222E3
Final cost
£500 million GBP

Crossrail Farringdon Station Execution

Service Performed
Tunnel design, engineering support, geotechnical engineering and site supervision services were provided.
Commencement - Services
March 01, 2013
Completion - Services
November 01, 2015
Location
39 Cowcross Street
London
EC1M 6BY
United Kingdom
Technical data

Located in the heart of Crossrail, Farringdon is one of London’s major rail interchange stations, providing connections between three networks (Thameslink, Crossrail and London Underground). Dr. Sauer & Partners provided 24/7 supervision support during the SCL works.

Geology description

The majority of the tunnelling takes place within the Lambeth Group formations.

Geology types
Soft ground
Description

Farringdon station is now one of London's major rail interchange stations, providing connections between three networks. During the construction of the Crossrail project, it also received four earth pressure balanced tunnel boring machines (TBMs): the two Drive X TBMs, running from Royal Oak to Farringdon and the two Drive Y TBMs, running from Limmo to Farringdon. The complete station layout will comprise two ticket halls, two platform tunnels, connecting cross passages, escape and ventilation adits, two escalator - inclines and two concourse tunnels constructed using mainly SCL tunnelling.

Activity
Bid cost
$300,000,000
Final cost
$400,000,000
Construction methods
Special Construction techniques
Tunneling under
Max Excavation Area (m2)
25-110m2
Tunnel length
1000m
Western ticket hall site overview
Cross passage 3 from platform tunnel east
Platform Tunnel West - RTE2 excavation - TBM Turn and Bury
Western Ticket Hall Site Overview I
Platform Tunnel West - TBM Tunnel Enlargement
Project number
222E5
Final cost
£400 million GBP

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