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Catégorie : Rails, Metro and Tunnels

Station de métro Msheireb de Doha

Publié sur par Sir Gwi

Station de métro Msheireb de Doha

La station Msheireb est la principale station d'échange du métro de Doha. Situé au centre-ville de Doha, il relie les trois lignes (Rouge, Verte et Or) et constituera une porte d'entrée pour les stades de la Coupe du Monde de la FIFA 2022.

La station Msheireb deviendra l’une des plus grandes stations de métro au monde en termes de taille.

TYMPANS COMPOSITES POUR LES TUNNELIERS for TBMs

For this major project, Dextra engineered and supplied between 2013 and 2015 8 large ASTEC GFRP Soft-Eyes, of a diameter of 8 meters each. Soft Eyes are cages of GFRP rebar, positioned into the D-Walls in-between steel segments. GFRP Soft-Eyes allow Tunnel Boring Machines (TBMs) to go through in a minimum time as the bars can be easily crushed by the tunnel machine.

Ancrages d'arrimage

To anchor the massive d-walls and prevent any soil displacement during excavation works, Dextra also supplied its ASTEC Active Anchors (AAA). Those innovative post-tensioned GFRP-based anchors, have the benefits of being cut by the Tunnel Boring Machines or standard excavation equipment. Because it can be easily cut, it doesn’t need to be removed from the ground, even when used for temporary applications.

Dans le cas des stations Msheireb, des ancrages multi-tendons (10 par ancrage sur ce projet) ont même été installés au centre de Soft-Eye pour ancrer le D-Wall. Ces ancrages ont également été coupés lors du percement du tunnel (visible dans la vidéo ci-dessous). Au total, 150 ancres ont été installées dans la station.

BTS de Bangkok

Publié sur par Sir Gwi

BTS de Bangkok

The Bangkok Mass Transit System (BTS) is a large urban skytrain system located in Bangkok, the capital of Thailand. The system was inaugurated in 1999.

As of 2017, the system consists of 24 elevated stations and 37 km of elevated rail organized into two main lines crossing each other at Siam central station.

The BTS system is undergoing an extension of its two main lines, with line segments and stations expected to enter into operation in 2019 and 2020.

Fondations

For various packages over the years, Dextra has supplied Sonitec tubes, which are used to test the concrete pile foundations beneath stations and tracks.

In total, Dextra supplied approximately 40,000 linear meters of Sonitec tubes, a distance actually equivalent to the BTS system’s length itself.

Pylônes

Pour les connexions de barres verticales de pylônes, Dextra a proposé ses Bartec solution.

Bartec allows contractors to conveniently splice prefabricated rebar cages using a simple rebar coupler, allowing savings in steel compared to overlap splicing and accelerating site operations.

In Thailand, the threading operation is supported by Dextra’s factory, conveniently located in the northeast of Bangkok. Contractors receive the rebar already prepared and mounted with their rebar coupler.

Agrandissement de la gare de Madrid Chamartín Clara Campoamor

Publié sur par Sir Gwi

Agrandissement de la gare de Madrid Chamartín Clara Campoamor

The Madrid Chamartín Clara Campoamor Railway Station expansion is one of the largest infrastructure projects in Spain. The expansion project aims to increase the capacity of the railway station and improve the overall passenger experience. Dextra supplied 60,000 linear meters of Sonitec, a crosshole sonic logging (CSL) testing tube, for the piling work of the project.

Madrid Chamartín Clara Campoamor Railway Station is one of Spain’s busiest railway stations, serving more than 60 million passengers each year. The expansion project was necessary to accommodate the increasing demand for train services in the city. The project involved the construction of new platforms, tracks, and passenger facilities.

Dextra, a leading supplier of construction solutions, was chosen to supply the Sonitec crosshole sonic logging (CSL) testing tube for the piling work of the project. The Sonitec tube is a highly advanced system that enables precise and accurate measurements of pile integrity. The system employs crosshole sonic logging technology to assess pile conditions, ensuring they are strong enough to support the weight of the railway station.

Using the Sonitec crosshole sonic logging testing tube enabled the construction team to carry out the piling work with confidence and ensured the structural integrity of the piles. The system provided real-time data on pile conditions, enabling the construction team to make informed decisions and implement any necessary adjustments during the construction process.



Crédit image bannière : UNStudio, b720 Arquitectura et Esteyco

Métro de Melbourne

Publié sur par Sir Gwi

Métro de Melbourne : cinq nouvelles stations de métro

Melbourne’s metropolitan rail service operates 226 six-carriage trains across 998 km of tracks. The metro has 15 lines and 222 stations, serving more than 400,000 passengers a day across the city.

In 2017, the construction of a 9 km-long tunnel and five new underground stations was announced to increase capacity and expand coverage in the city’s suburban area.

Construction began in 2018. Dextra was involved in the project by supplying rebar connectors with fully automated rebar preparation equipment for the station’s structural Armatures works.

Griptec couplers were chosen for their unrivaled performance in tension, compression, and fatigue, with 400,000 units delivered.

In addition, Dextra supplied:

  • 5,300 PRFV Astec Combination Bolts — These were used at the CBD cavern location. The 19m width of the cavern allowed for the construction of two conventional 7m tunnels, built in parallel with the middle segments secured by PRFV CB Bolts, which can be cut to widen the gallery.
  • 2,400 PRFV Geotec GR45 – 25mm dowels — Each measuring 11.8 meters, these dowels were used to secure the excavation face.
  • 900 PRFV Astec Soil Nails ST50 – 41 — These were applied to secure several stations under construction. Some of them extend beyond the project boundary since PRFV can remain in the ground and be easily cut later.
  • 16 Soft-Eyes — Installed in the D-Wall and bored pile of five stations.

Dextra provided support and shared its expertise on PRFV during the design stage, producing custom-shaped PRFV solutions to meet the owner’s expectations. Due to the cuttability of PRFV, the TBM can pass through the D-Wall in minimal time without causing damage.

The metro tunnel and its new stations are due to open in 2025 and are predicted to become a new landmark for the city.

(Crédit photo : Hugh Llewelyn sur https://bit.ly/2S0kbAG)

Métro de Delhi Phase 3

Publié sur par Sir Gwi

Métro de Delhi Phase 3

The Delhi Metro is the largest and busiest rapid transit system in India, serving Delhi and its satellite cities of Ghaziabad, Faridabad, Gurgaon, Noida, Bahadurgarh, and Ballabhgarh. It operates over 2,700 trips daily.

The system currently consists of 10 color-coded lines serving 253 stations with a total length of 348 km, including a mix of underground, at-grade, and elevated stations.

The network’s development was divided into phases. Phase 1 and Phase 2 were completed by 2006 and 2011, respectively. Phase 3 includes 35 underground stations and three new lines, totaling 167 km, and is scheduled for substantial completion by the end of 2020.

The total length of the underground corridors in Phase 3 is 54 km — more than 20 km longer than the total underground sections in Phases 1 and 2 combined — making it one of the most challenging construction stages.

More than 20 tunnel boring machines (TBMs) were used simultaneously to expedite the tunnel work through 10 Dextra Soft-Eyes installed in diaphragm walls. Thanks to the cuttable nature of GFRP (glass fiber reinforced polymer) bars, TBMs can enter or exit shafts and stations in just a few minutes.

Furthermore, 450 sets of active anchors were installed to retain walls during the excavation work. The anchors are also made of GFRP, eliminating the need for anchor removal.

Approximately 2.3 million Bartec couplers were installed to connect rebars in various parts of the concrete structures of the stations. Bartec is a bar-break performance system designed to withstand an ultimate tensile strength of up to 800 MPa.

In addition, 2,800 Shear Key post-tensioning systems were installed in concrete recesses as permanent seismic restrainers for the connection of the elevated metro segments.

Lien avec la ville de Perth

Publié sur par Sir Gwi

Lien avec la ville de Perth

The Perth City Link is a transport and urban development project taking place in Perth, Western Australia. It aims to reclaim more than 13.5 hectares of land previously occupied by connecting railways by sinking a train line, thus making land available at the surface to reconnect two parts of the city with streets, commercial, and residential buildings.

For this project, Dextra was involved between 2012 and 2014 in the early foundation works:

  • Supplied Dextra Épissage mécanique des barres d'armature Rolltec solution, which was used for the vertical connection of rebar in D-Walls and micropiles. Rebar couplers were used to reconnect cages that had been prefabricated by our rebar partner fabricator in Perth.
  • Dextra a également fourni son Sonitec sonic tubes used for Cross Sonic Logging (CSL) integrity testing of the foundation piles.

For more information about foundation solutions available in Australia, please contact our Bureau de Bangkok.

Métro de Riyad

Publié sur par Sir Gwi

Métro de Riyad

The Riyadh Metro is a massive urban transit system project under construction in Riyadh, Saudi Arabia. The project will feature 85 stations built along six transit lines, with a total rail length of 176 km. The system is expected to serve at least 1 million passengers daily upon its inauguration in 2018.

For this large infrastructure project, Dextra has been involved in various stations and packages.

Excavation Works

Before proceeding with general construction works, during the early excavation phase, retaining walls must be anchored back into stable ground to prevent any wall displacement. This will allow excavation to continue safely.

For that purpose, Dextra supplied steel ground anchors installed at the station perimeter. Each system consists of a high-tensile fully threaded bar, accompanied by a nut and plate, and grouted to bond with the soil.

For more information, please refer to the Steel Ground Anchors page.

Raft and Vertical Connections

Bartec rebar couplers were supplied for the works in the stations. Couplers were used for slabs, columns, and wall connections. A typical application on this project was to cast rebar couplers in the concrete with reinforcement and then proceed with second-phase bar connections at a later stage.

Unitec bolted couplers have also been used in various parts of the project. Typically, Unitec is used when overlap is planned but the lapping length appears to be too short to perform a safe splice. In that case, Unitec provides a convenient and full-performance connection.

Métro de Pune UG 04 – Station de métro Swargate

Publié sur par Sir Gwi

Métro de Pune UG 04 – Station de métro Swargate

Pune Metro is an under-construction mass rapid transit system that comprises three lines with a total length of 55 km. The Metro is in the Pune Metropolitan Region, Pune City, India.

Swargate Station is part of the 17-km Line 1 running from PCMC Building to Swargate. Lines 1 and 2 were expected to become operational in 2021, while the elevated Line 3 was scheduled for completion one year later.

For this project, Dextra supplied more than 1,700 steel active anchors to stabilize vertical retaining walls around the excavation area.

Dextra’s Geotec Steel Active Anchor is the preferred solution for excavation projects requiring post-tensioning.

Active Anchor

 

Ancres actives

The anchors are corrosion-protected and designed with high-tensile, fully-threaded bars that help prevent deformation of the retained structure.

Once the construction of Pune Metro UG04 is completed, the underground station at Swargate will be a strategic part of a multimodal transit hub connecting to city bus services and parking facilities for private vehicles.

Extension de la ligne MRT Thomson-East Coast de Singapour

Publié sur par Sir Gwi

Extension de la ligne MRT Thomson-East Coast de Singapour

The Thomson-East Coast Line is a future MRT line in Singapore that will connect the Thomson Line with the Eastern Region Line. The 43-km link will add 31 new stations to the existing rail network, with seven interchange stations.

For that project, Dextra supplied numerous packages, including Marine Terrace Station, where four large-diameter TYMPANS COMPOSITES POUR LES TUNNELIERS were installed in the diaphragm wall cages in August 2017.

Soft-Eyes are made of GFRP rebar, which is used to replace the steel reinforcement in the D-Walls of construction shafts. When the Tunnel Boring Machine (TBM) breaks through the D-Walls, it easily cuts the GFRP bars, saving time in the project schedule and reducing equipment costs.

Dextra pioneered this application in the Bangkok metro project in 1998 and has extensive experience in the in-house design and manufacturing of Soft-Eyes.

The D-Walls installed at Marine Terrace Station also feature Bartec® rebar couplers, a common solution for reconnecting slabs horizontally in underground stations. Bartec couplers are also widely used for vertical connections in foundation piles and slabs.



Ligne 6 du MRT de Dacca

Publié sur par Sir Gwi

Ligne 6 du MRT de Dacca

Dhaka Metro Rail is a mass rapid transit system under construction in Dhaka, the capital and busiest city of Bangladesh.

MRT Line 6 consists of 16 elevated stations, each 180 meters long, and 20.1 kilometers of electrified light rail tracks. Except for the depot and some sections of the LRT (Light Rapid Transit) that will run beside it, Line 6 will be elevated over current roadways, largely above road medians, to allow traffic to flow beneath it, with stations likewise elevated.

Dextra supplied various solutions to the project:

  • 50,000 linear meters of Sonitec, an easy-to-assemble and time-saving tube solution used for CSL (crosshole sonic logging) testing of foundation piles.
  • 1,000 Shear Key systems, a post-tensioning bar system that acts as a permanent seismic restrainer for the connection of elevated metro precast segments.
  • More than 50,000 Bartec couplers were also used for the reinforcement of the station structures.

Line 6 construction was anticipated to be completed in 2022.