The Dubai Metro is a urban transit rail system operating in Dubai, United Arab Emirates. Two lines are currently operational, the Red Line and Green Line. Additional lines are also planned for coming years.

For the construction of the Red Line, Dextra has been involved between 2005 and 2010 together with the contractors making J T Metro (Obayashi Corporation – Kajima – YapiMerkezi) for the supply of numerous Dextra solutions for various packages and stations.

For the station construction, especially for the foundation works (piles and perimeter d-walls), Dextra supplied its Bartec rebar splicing solutions. Rebar couplers were used for vertical connections in piles D-Walls, columns and piers. Rebar couplers were also used for reconnecting slabs onto the D-Walls. A total of 800,000 Bartec rebar couplers have been supplied for this project, supported by several Bartec equipment sets maintained by local Dextra Aftersales team.

For minor repair applications, RéparationGrip couplers were also supplied to splice rebar which had not be prepared with a thread and which had unsufficient produding length to be spliced.

For foundation works as well. Dextra supplied more than 60km of Tubes soniques Sonitec, used the CSL integrity testing of piles and walls. Sonitec can be easily assembled at site thanks to their push-fit mouth system, boosting teams productivity and avoiding the tedious task of welding tubes together.

Finally, to accelerate tunneling breakthrough phases and minimize TBMs (tunnel boring machines) time when exiting/entering shafts and stations, Dextra engineered the design of GFRP Soft Eyes and supplied more than 400 km of composite rebar for numerous station packages.

Coimbra B-Portagem Mondego Metro project is part of the mass transit public transport system of Coimbra, Portugal. Dextra has played a significant role by providing Sonitec tubes for pile testing.

Dextra has supplied Sonitec tubes for testing a total of 67 piles ranging from 12 to 19 meters in depth. The tubes have been instrumental in conducting these tests with the Cross-Hole Sonic Logging (CSL) methodology.

The innovative push-fit connection system of Sonitec has greatly reduced labor time during installation. Thanks to this user-friendly system, the contractor has experienced smoother and more efficient pile testing processes. By eliminating the need for additional labor-intensive procedures, the contractor has saved valuable time and resources. It also ensures a secure and reliable connection between piles.

London Crossrail (appelée Elizabeth Line en 2016) est le plus grand projet d'ingénierie en Europe. Il s'agit d'une partie importante du programme d'investissement de Transport for London et du plus grand ajout au système de transport depuis 50 ans.

Le projet consiste en une liaison ferroviaire est-ouest de 118 km à travers le Grand Londres, qui s'étendra de Reading et Heathrow à l'ouest jusqu'à Shenfield et Abbey Wood à l'est.

Depuis 2009, Dextra a livré plus de 600 000 connexions Griptec sur plus de 20 forfaits comprenant des stations telles que :

• Rue de Liverpool
• Paddington
• Rue des obligations
• Quai Canary
• Portail Royal Oak
• Ruelle du moulin à pudding

Les coupleurs Griptec ont été utilisés sur les murs en D (connexions verticales et horizontales), les colonnes et les pieux (connexions verticales).

Les segments de Crossrail devraient commencer à fonctionner progressivement, l'achèvement complet étant prévu pour décembre 2019.

The Rio de Janeiro Line 4 is a subway line. It is part elevated and part underground (2 segments). The line has been planned to open for the 2016 Rio de Janeiro Summer Olympics.

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

Avant la construction du mur en D, Dextra conçoit la conception de la cage FRP en tenant compte de la taille du tunnelier, de la marge d'erreur, des forces du sol et d'autres paramètres de conception.

Thanks to the properties of FRP material, Tunnel Boring Machines cut through the D-Wall in a minimum time, saving time on 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 the water entry into the station excavations.

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

Couplers were also used horizontally to provide a reconnection point for slabs (at station level and at the surface) in the D-Walls.

Nagpur, the second capital of Maharashtra and one of the fastest developing city in India is witnessing major growth in terms of Infrastructure. The development encompasses primarily the connectivity, of which Metro rail becomes a major part.

Incepted in 2016, the metro project is being a subject of acclaimed discussion for its speed of execution and the quality of construction.

Within the city boundaries, it requires the highest standards of safety considerations including the seismic analysis of structure in service life.

Project Requirement

The fast track project has typical structure for its Line 1 alignment, where the viaducts are supporting 2 levels of pathways, lower one for NH-7 and upper one for the metro rail. As the impact loading is a big concern due to train movement.
Being the stretch of always busy traffic, a solution was required which does not have to revise the existing design. Plus a major concern was the impact on speed of the otherwise fast moving project. The issue was concerning to all the stakeholders especially the GC for the project, who were looking to maintain the agility as well as find a sustainable solution.

Solution

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

Le métro de Doha est un système de transport rapide, conçu comme partie intégrante du réseau ferroviaire plus vaste du Qatar. Ce projet d'infrastructure à grande échelle à l'échelle nationale comprend 300 km de voies ferrées et 100 gares. Le réseau ferroviaire vise à réduire les embouteillages et à relier la population du Qatar au reste de la région du CCG. À l'échelle de la ville, actuellement en construction, le métro devrait être opérationnel d'ici fin 2019. Il desservira Doha et ses banlieues environnantes avec des stations situées dans tous les nœuds majeurs de la métropole. Le métro de Doha fonctionnera à la fois au niveau du sol et en sous-sol, la majorité du projet de métro étant souterrain. Des solutions complexes de tunnelage et de rétention des sols de Dextra ont été utilisées dans la construction de ce projet.

Polymères renforcés de fibres de verre (GFRP) comme ancrages pour retenir le sol

Pour éliminer les problèmes d'empiétement et les obstacles pour les futurs projets de construction, le mur moulé (mur en D) de la station Al Sadd avec anneau en C a été ancré en post-tension avec l'ancrage actif ASTEC. Ces ancrages GFRP haute performance et entièrement découpables ont été choisis par les entrepreneurs ALSYJ JV et les ancrages D-Wall de choix. Cette solution innovante a été choisie car elle peut être creusée par des tunneliers (TBM) ou des équipements d'excavation standard, et elle n'a pas non plus besoin d'être retirée du sol, même dans les applications temporaires. Pour la station Al Sadd C-Ring, 7 113 torons pour barres d'armature en PRV ont été utilisés pour fabriquer environ 700 ancrages de retenue au sol utilisés dans le MUR en D autour de cette station.

The Second Ho Chi Minh City Environmental Sanitation Project consists of the construction of interceptor that will convey the wastewater collected from the Nhiêu Lộc-Thị Nghè Canal and District 2 areas of Ho Chi Minh City to the 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 (GFRP) Soft-Eyes were applied to reinforce 21 shafts, allowing the penetration by the Tunnel Boring Machine (TBM) without the need of removing steel reinforcement and without the risk to damage the TBM’s head.

With its completion, planned to be in 2022, the wastewater services in HCMC will have a considerably more sustainable nature, and will be remembered as the first big step toward the alleviation of the environmental and sanitation issues of the Country.