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Catégorie : Transport

Métro de Chennai

Publié sur par Sir Gwi

Métro de Chennai

The Chennai Metro is an urban transport system in the city of Chennai, a large and fast-developing city in the south of India. The system comprises four lines, partly underground and partly elevated, and a total of 42 stations. Construction started in 2009, with the first line opening to the public in 2015. The total planned length of the system exceeds 45.1 km.

Underground Stations

For this large construction project, Dextra was involved between 2011 and 2015 in the design, engineering, and supply of 61 FRP Soft Eyes for station entry/exit points as well as TBM insertion/extraction shafts.

Thanks to the properties of FRP material, Tunnel Boring Machines cut through the D-Wall in minimal time, saving time in the schedule and ensuring the perfect condition of the TBM’s head.

Elevated Segments

As a complement to Soft-Eyes for underground parts of the lines, Dextra also supplied Post-Tensioning Bar Systems for permanent applications.

The PT systems connect piles and precast segments of the elevated viaduct (shear key and hold-down applications). Each bar system, composed of high-tensile performance bars, plates, and nuts, is post-tensioned to provide seismic resistance.

For each of the 1,000 sets used on the Chennai Metro, Dextra also supplied the corrosion accessories necessary for this type of permanent application.

D-Walls

Finally, 350,000 Bartec couplers were also used vertically and horizontally in the station D-Walls.

Horizontal connections are performed with couplers left pending. Reconnection is done once the station is excavated, with second-phase rebar being reconnected to start the slabs.

Ligne 4 du métro de Rio

Publié sur par Sir Gwi

Ligne 4 du métro de Rio

Rio de Janeiro Line 4 is a subway line that is partly elevated and partly underground, with two segments. The line was planned to open for the 2016 Rio de Janeiro Summer Olympics.

Dextra was involved between 2013 and 2015 in the design, engineering, and supply of four large FRP Soft-Eyes for station entry/exit points. These Soft-Eyes were the first ever delivered on the South American continent.

Prior to D-Wall construction, Dextra engineered the FRP cage design, taking into account the size of the TBM, margin for error, soil forces, and other design parameters.

Thanks to the properties of FRP material, Tunnel Boring Machines cut through the D-Wall in minimal time, saving time in the schedule and ensuring the perfect condition of the TBM’s head. The time factor is especially important in humid environments such as Rio to limit water entry into the station excavations.

On this project, Dextra also supplied Rolltec Rebar Couplers, used as vertical connectors in the station diaphragm walls to reconnect cages.

Couplers were also used horizontally to reconnect slabs at station level and at the surface in the D-Walls.

Métro de Nagpur, Reach-1 (ligne 1)

Publié sur par Sir Gwi

Métro de Nagpur, Reach-1 (ligne 1)

Nagpur, the second capital of Maharashtra and one of the fastest developing cities in India, is witnessing major growth in terms of infrastructure. The development primarily focuses on connectivity, with the Metro rail playing a major role.

Launched in 2016, the metro project has been widely praised for its speed of execution and the quality of construction.

Within the city boundaries, the project requires the highest safety standards, including seismic analysis for structural integrity throughout its service life.

Project Requirements

The fast-track project features a typical structure for its Line 1 alignment, where the viaducts support two levels of pathways: the lower one for NH-7 and the upper one for the metro rail.

Impact loading due to train movement was a major concern. Since the stretch is always busy with traffic, a solution was required that would not require revising the existing design. Additionally, minimizing delays to this fast-moving project was critical, a concern shared by all stakeholders, especially the General Consultant (GC), who sought to maintain project agility while ensuring a sustainable solution.

Solution

Dextra introduced Shear Key Bars for the priority section, allowing the structure to neutralize seismic forces. This not only helped the contractor complete the work faster but also enabled the client to conduct the trial run earlier than expected.

Métro de Doha, ligne Gold – station Al Sadd C-Ring

Publié sur par Sir Gwi

Métro de Doha, ligne Gold – station Al Sadd C-Ring

The Doha Metro is a rapid transportation system designed as an integral component of the larger Qatar rail network. This country-wide, mega-scale infrastructure project consists of 300 km of rail and 100 stations. The rail network aims to reduce traffic congestion and connect the people of Qatar with the rest of the GCC region.

At the city scale, the metro is currently under construction and projected to be operational by the end of 2019. It will serve Doha and its surrounding suburbs, with stations located in all major nodes of the metropolis. The Doha Metro will operate both at grade and below grade, with the majority of the metro project being underground. Dextra’s complex tunneling and soil-retaining solutions were utilized in the construction of this project.

Glass Fiber Reinforced Polymers (GFRP) Used as Tie-back Anchors to Retain Soil

To eliminate concerns of encroachment and obstacles for future construction projects, the Diaphragm Wall (D-Wall) at Al Sadd C-Ring Station was post-tensioned and anchored with ASTEC Active Anchors. These high-performance, fully cuttable GFRP anchors were chosen by ALSYJ JV contractors as the D-Wall anchors of choice.

This innovative solution was selected because it can be cut by Tunnel Boring Machines (TBMs) or standard excavation equipment, and it does not need to be removed from the ground, even in temporary applications.

For Al Sadd C-Ring Station, 7,113 strands of GFRP rebars were used to make approximately 700 ground-retaining anchors in the D-Wall around that station.

2ème HCMV Environnement Assainissement

Publié sur par Sir Gwi

2ème HCMV Environnement Assainissement

The Second Ho Chi Minh City Environmental Sanitation Project consists of the construction of an interceptor that will convey the wastewater collected from the Nhiêu Lộc-Thị Nghè Canal and District 2 areas of Ho Chi Minh City to a treatment plant.

Dextra has been involved in the construction of the large underground system by supplying 40 Soft-Eyes to assist in the tunnel breakthroughs.

The cuttable Glass Fiber Reinforced Polymer (PRFV) Soft-Eyes were applied to reinforce 21 shafts, allowing penetration by the Tunnel Boring Machine (TBM) without the need to remove steel Armatures and without the risk of damaging the TBM’s head.

With its completion planned for 2022, wastewater services in HCMC will become considerably more sustainable and will be remembered as the first major step toward alleviating the environmental and sanitation issues of the country.

Métro de Doha – Phase 1

Publié sur par Sir Gwi

Métro de Doha – Phase 1

Doha Metro Phase 1 is Qatar’s major infrastructure project consisting of three metro lines with a total length of 164 km. The first phase involves the construction of the Red, Green, and Gold lines and their major stations. It is part of the US$36 billion Doha Metro Rail Network Project, aiming to reduce the city’s road traffic congestion while facilitating the connection between Qatar and other Gulf countries.

The required completion period for this project is extremely short, with excavation starting in mid-2013 and operations expected by 2019. Given the project’s constrained timeline, highly innovative solutions are required to complete the building of underground structures in minimal time.

Dextra’s FRP Active Anchors as Temporary Tie-backs in Retaining Walls

Composite materials have been used for over 20 years as temporary reinforcement in concrete structures. In Doha Metro Phase 1, both Dextra’s post-tensioned carbon-FRP (CFRP) Active Anchors and glass-FRP (GFRP) Active Anchors have been used in retaining walls.

When used as temporary tie-backs, CFRP material offers the most advanced technical solution due to its superior tensile strength, creep resistance, and durability, while GFRP Anchors offer a cost-effective solution without technical compromise.

GFRP anchors can advantageously replace steel removable anchors to prevent encroachment on neighboring plots. As a result, GFRP anchors now account for more than 90% of the FRP anchors installed in the region.

For the first phase of the Doha Metro Rail Network project, Dextra has supplied 150 CFRP Active Anchors and 700 GFRP Active Anchors to date.

ASTEC Soft-Eye for Improved TBM Penetration

Dextra’s ASTEC Soft-Eyes is a unique technology using cuttable GFRP reinforcement as a replacement for conventional steel rebars. Since 1996, this solution has become a standard concept in the design of shafts and subway stations.

More than 10 sets of Dextra’s ASTEC Soft-Eyes had been supplied and used in the Doha Metro construction project as of May 2018.

Mexico – Toluca Inter-city train (Tren Interurbano México – Toluca)

Publié sur par Sir Gwi

Mexico – Toluca Inter-city train (Tren Interurbano México – Toluca)

o reduce traffic congestion on the Mexico–Toluca highway, as well as to ease connections between both cities, the Secretariat of Communications and Transportation (SCT) is constructing a new 55.7-kilometer rail line in the Mexico City area. Aiming to be an environmentally friendly project, the commuter rail line includes a 4.7-kilometer double-tube tunnel in highly complex terrain and protected natural areas.

The new train will connect Toluca Valley to Mexico City and will provide service to an estimated 270,000 commuters. The line includes six stations: two terminals (Zinacantepec and Observatorio) and four intermediate stations (Cristobal Colon, Metepec, Lerma, and Santa Fe). It will also serve as a backbone for regional and urban transport in the Mexico City area.

Construction began in 2015, and the railway was scheduled for completion in 2019.

Light and Productive Rebar Coupler Solution for the Construction Project

For the reinforcement of the railway’s concrete structures, Dextra supplied more than 100,000 Rolltec splices. The system is a practical and economical alternative to laps. Rolltec is also supported by a single rebar preparation machine, and only one operator is needed to run the machine.

In addition, thanks to the performance of our machines, the thread is prepared in less than 30 seconds!

Moreover, with the Rolltec system, the same type of coupler can be used for both standard and position applications, resulting in optimized project inventory.

For more information about our projects in Latin America, please contact our Panama office.

Métro du Caire – Ligne 3

Publié sur par Sir Gwi

Métro du Caire – Ligne 3

Depuis l'ouverture du premier segment de 29 km de la ligne 1 du métro en 1987, le projet de métro du Caire a révolutionné le système de transport en commun de la capitale.
Actuellement, l'ensemble du réseau comprend 3 lignes opérationnelles numérotées de 1 à 3. La ligne 3 se compose de quatre phases et le premier segment a été mis en service en 2012.

Trois nouvelles stations de métro ont été inaugurées dans le cadre de la quatrième phase de la troisième ligne le 15 juin 2019, une semaine avant le coup d'envoi de la Coupe d'Afrique des Nations 2019 (CAN) au Caire.

Dextra a continuellement fourni des solutions de construction depuis l'exploitation de la ligne 2 en 2000, livrant depuis lors plus de :

-1 400 000 coupleurs de barres d'armature

-7 000 tubes soniques

-60 yeux doux

Les coupleurs de barres d'armature Bartec sont utilisés pour le renforcement des barres d'armature des structures de tunnels et de gares sur les lignes de métro souterraines et surélevées afin de réduire la congestion de l'acier et d'améliorer la connexion en traction.

De plus, le test d'intégrité des fondations du métro à l'aide de la méthode de test Cross Sonic Logging (CSL) a été facilité par l'utilisation de tubes soniques SONITEC, conçus pour un assemblage et une installation faciles dans des cages d'armature.

Les yeux souples ASTEC de Dextra sont fabriqués à partir de barres d'armature en PRV pour renforcer les murs en D dans les tunnels souterrains, qui peuvent facilement être coupés par un tunnelier (TBM), ce qui permet des économies de temps et d'argent.

Le projet est toujours en cours et la quatrième ligne du métro du Caire devrait entrer en service en 2020.

Métro Nagpur, station de métro Zero Mile

Publié sur par Sir Gwi

Métro Nagpur, station de métro Zero Mile

Station de métro Nagpur Zero Mile dans un projet à usage mixte de transport/parking/commercial se déroulant dans la ville de Nagpur, dans l'État du Maharashtra. Il est situé sur la nouvelle ligne de métro traversant la ville du Nord au Sud. La Station Zero Mile est une station de métro combinée à un bâtiment de 12 étages qui accueillera des zones commerciales et un parking d'une capacité de 430 véhicules.

Pour ce projet, Dextra a été impliqué en 2017 pour la fourniture et l'installation d'ancrages au sol pour la stabilisation du sol autour de la zone d'excavation.

Dextra a fourni sa solution innovante d'ancrages actifs ASTEC (FRP) (AAA), un type spécial d'ancrages au sol qui, dans le cas d'applications temporaires, peuvent être laissés dans le sol une fois le projet terminé, même si ceux-ci s'étendent au-delà des limites de propriété ou traversent de futurs tunnels.

En effet, l'un des principaux avantages de la barre d'ancrage FRP est de rendre l'ancre entièrement découpable par l'équipement d'excavation conventionnel, ce qui en fait le meilleur substitut aux ancres amovibles conventionnelles qui sont des ancres en acier qui doivent être retirées du sol par force brute à la fin. de projet.

Les ancrages actifs Dextra ASTEC sont légers à transporter et peuvent être transportés jusqu'à leur emplacement final par les travailleurs. Une fois insérée dans le trou foré, chaque ancre est injectée puis contrainte par l'utilisation de torons PT conventionnels connectés à l'ancre FRP. Après l'installation, l'ancrage peut rester dans le sol, contrairement aux ancrages amovibles classiques qui nécessitent une gestion de projet supplémentaire et génèrent des coûts de retrait d'ancrage en fin de vie.

Pour plus d'informations sur les solutions d'ancrage Dextra en Inde, veuillez contacter notre Bureau de Bombay.

Métro de Hô Chi Minh-Ville – Ligne 1 (Métro HCMV, Vietnam)

Publié sur par Sir Gwi

Métro de Hô Chi Minh-Ville – Ligne 1 (Métro HCMV, Vietnam)

Ho Chi Minh City Metro – Line 1 is the first part of the megacity’s 109-kilometer rail line project undertaken by the Management Authority for Urban Railways (MAUR).

Une fois réalisé, le système de transport en commun couvrira les zones de HCMV avec 6 lignes de métro, permettant aux habitants et aux touristes de se déplacer facilement et commodément dans la ville, ce qui se traduira par une meilleure qualité de vie urbaine.

La première phase du projet consiste en la construction d'une ligne ferroviaire de 19,7 kilomètres reliant le marché Ben Thanh et le parc Suoi Tien. Il comprend également la construction d'une voie ferrée surélevée de 17,1 kilomètres avec 11 stations et d'une ligne souterraine de 2,6 kilomètres avec 3 stations.

For the construction of Vietnam’s biggest city, Dextra has been supplying both concrete reinforcement et bar system solutions.
To reduce steel congestion in heavily reinforced areas, the contractor Shimizu-Maeda Joint Operation opted for Dextra’s end anchors. Têtes d'ancrage is a simple alternative to rebar hooks.

L'installation se fait en vissant uniquement la plaque d'ancrage compacte sur l'extrémité de la barre de renfort. La solution facilite finalement le processus, ce qui se traduit par une meilleure qualité de bétonnage.