Dextra Group | Reliable Connections

Chennai Metro Phase 2, India

Chennai Metro Phase 2, India

The Chennai Metro Phase 2 project is set to redefine urban transportation in one of India’s largest cities, promising enhanced connectivity and efficiency. Playing a pivotal role in the success of this ambitious project, Dextra has supplied an array of cutting-edge construction solutions to meet the project’s demanding structural and safety requirements. Ensuring Robust Connections with Bartec Rebar Couplers Dextra supplied nearly 2 million Bartec rebar couplers, essential for creating secure connections across various structural components. These couplers have been utilized extensively in the connections for diaphragm wall (d-wall) caging and slabs, pile cages, piers, and pier caps. By ensuring high-strength rebar connections, Bartec couplers contribute to the overall durability and resilience of the metro structure, particularly important in a densely populated and busy urban environment like Chennai. Precision Testing with Sonitec CSL Testing Tubes To ensure the highest standards of concrete integrity, Dextra provided over 80,000 Sonitec crosshole sonic logging (CSL) testing tubes. These tubes facilitate rigorous testing of piles and d-walls, helping to identify potential flaws within the concrete structure. This meticulous testing process enables project engineers to detect and address any irregularities, safeguarding the integrity and longevity of the metro’s foundations. Supporting Complex Structures with CR Bar 1080 Post-Tensioning Bars For the support of double-decker piers and the pre-tensioning of U-girders, Dextra supplied 68 CR Bar 1080 post-tensioning bars. These high-strength, fully threaded bars are critical in handling the complex loads and stresses that the elevated sections of the metro will endure. The inclusion of these bars ensures that the metro can withstand heavy traffic and operational demands over time, contributing to the long-term safety and functionality of the infrastructure.
Facilitating Tunnel Boring with GFRP Soft-Eyes In the tunneling phase, Dextra also provided 42 GFRP soft-eyes, specifically designed for tunnel boring machine (TBM) operations. These soft-eyes allow TBMs to pass through concrete walls smoothly, ensuring safe and efficient tunneling while reducing the risk of structural damage. GFRP’s non-corrosive properties make it an ideal choice for underground construction, where durability and performance are paramount. Building a Safer, Stronger Future Dextra’s commitment to supplying top-tier construction materials and solutions underscores its dedication to the Chennai Metro Phase 2 project. As the metro takes shape, Dextra’s innovations contribute not only to the project’s success but also to the future of Chennai’s urban infrastructure, setting new standards in construction excellence and sustainability.

Mumbai Metro Line 2B, India

 

Mumbai Metro Line 2B, India

 
 

The Mumbai Metro Line 2B, an essential link connecting several key areas of the city, is a significant infrastructure project aimed at alleviating Mumbai’s traffic congestion and providing efficient public transport. As part of this ambitious project, Dextra has made a valuable contribution, supplying engineered construction materials to ensure the durability and reliability of the structure.

CR Bar 1080 for U-Girder Stressing and Pre-Tensioning

One of the critical components of the project is the elevated section of the metro, which relies on U-girders for support. To enhance the strength and resilience of these U-girders, Dextra supplied its innovative CR Bar 1080 cold-rolled fully threaded post-tensioning bars. These bars, with a diameter of 75mm, are specifically designed to withstand high stress during both U-girder stressing and pre-tensioning operations. The hexagonal nuts provided as part of the system allow for secure fastening and easy adjustment, ensuring precise tensioning to meet the structural demands.

 

Fully Threaded (FT) Bar for Segment Stitching and Temporary Stressing

For segment stitching and temporary stressing operations during the construction of the metro viaduct, Dextra supplied its fully threaded (FT) bars. These bars provide secure connections between precast segments and offer flexibility for adjustments during the stitching process, ensuring that the structural alignment is perfect before the segments are permanently joined.

Unitec Couplers for Rebar Connections

In addition, Dextra supplied Unitec couplers, designed for connecting rebars at construction sites without the need for pre-threading. These couplers offer a convenient and robust solution, allowing for seamless connection of two rebars, ensuring structural continuity and strength without delays in the construction process.

Sonitec CSL Testing Tubes for Concrete Pile Integrity

In addition to supplying post-tensioning bars, Dextra also provided Sonitec Crosshole Sonic Logging (CSL) testing tubes for the integrity testing of the concrete piles supporting the metro structures. These tubes enable highly accurate non-destructive testing of the concrete, allowing engineers to detect any potential flaws or weaknesses in the piles. This testing is vital for ensuring the piles meet the necessary strength and quality standards, thereby supporting the entire metro system safely and effectively.

Enhancing Metro Connectivity with Quality Solutions

As the Mumbai Metro Line 2B progresses towards completion, Dextra’s contributions to the project highlight its role in providing advanced engineering solutions for infrastructure development. The combination of CR Bar 1080 for post-tensioning, fully threaded bars for segment stitching, Unitec couplers for rebar connection, and Sonitec CSL testing tubes for pile integrity showcases Dextra’s commitment to quality, innovation, and safety in major construction projects.

By contributing to this key metro line, Dextra is playing a part in shaping the future of urban mobility in Mumbai, ensuring that the metro system will be reliable and capable of supporting the city’s growing transportation needs for years to come.

King Abdullah Financial District, Saudi Arabia

King Abdullah Financial District, Saudi Arabia

The King Abdullah Financial District (KAFD) is a multipurpose business and residential complex located in Riyadh, Saudi Arabia. The district consists of more than 50 towers and is expected to accommodate a working population of around 12,000 people.

Dextra Middle East, based in Dubai, has been involved since 2009 in supplying several building packages to Saudi Bin Ladin Group, the main contractor for the project.

Foundation Piles

To provide vertical connections in foundation piles, Dextra supplied its popular Bartec rebar coupler solution—the #1 rebar splicing solution in the Middle East—through its fabrication partners.

In addition to Bartec couplers, Dextra also supplied Unitec couplers, which were used for the continuation of bars protruding from the foundation piles. Unitec offers a flexible solution for contractors, as it does not require prior bar-end preparation. It only requires an impact wrench, making it easy to operate, especially on remote construction sites.

Raft and Columns

Bartec couplers were also used for horizontal connections in the thick foundation rafts and vertical connections in the protruding columns.

Core Wall-to-Beam Applications

In the building superstructure, Dextra Bartec couplers were used to provide horizontal connections from the core wall, enabling the insertion of second-phase starter bars needed to create the beam reinforcement.

Parque da Cidade, Brazil

Parque da Cidade, Brazil

Parque da Cidade is a multi-tower, multi-purpose green building complex located in the south of São Paulo. The project features five corporate office towers, a hotel, residential buildings, and a shopping mall.

For this project, Dextra supplied its Rolltec rebar coupler solution to contractor Odebrecht.

Rolltec is the most popular rebar splicing solution in Brazil, offering a competitive alternative to lap splices and, more importantly, enabling advanced applications that simplify project management and operations.

At Parque da Cidade, Rolltec rebar couplers were used to connect columns and beams. The solution was supported by Rolltec bar-end preparation equipment installed on-site and maintained by Dextra’s local engineers.

For this application, rebar couplers were aligned horizontally within the column reinforcement at each floor and cast into concrete. Dextra provided its couplers with thread protection caps to prevent liquid concrete from leaking into the couplers.

At a later stage of the project, continuation bars were directly connected into the couplers, providing convenient starter bars for beam or slab reinforcement.

Additionally, Dextra supplied its Unitec solution for Parque da Cidade. Unitec is a bolted coupler that does not require any rebar preparation. It was used to connect rebars protruding from two precast elements.

Jamnagar refinery expansion

Jamnagar Refinery Expansion: The World’s Largest Refinery by Production Capacity

Located in Gujarat, western India, the Jamnagar Refinery is the largest refinery in the world by production capacity. Owned by Reliance Industries, it was commissioned in 1998 and spans a vast 50 km² area.

For Phase 3 alone, more than 305,000 tons of steel reinforcement were used in a 36-month project, involving over 100,000 engineers and construction workers.
Dextra has been involved in Jamnagar since the early phases, supplying rebar splicing solutions for Phases 1, 2, and 3 of the project.

Dextra’s Rebar Splicing Solutions for Phase 3:

Three rebar coupler solutions were used in Phase 3:

  • Bartec Solution
    Used for cast-in-situ applications, including bar-to-bar connections in foundations, pile cages, and column cages.
    Also utilized in heavily congested rafts and pile caps to facilitate efficient rebar splicing.
  • Groutec Couplers
    Applied to pipe racks, which were constructed from precast elements in a dedicated precast factory within the project.
    Positioned in the bottom elements and filled with grout, eliminating the need for in-situ wet joints and ensuring fast, secure connections between beams and columns.
  • Unitec Couplers
    Used in applications where rebar length was too short to allow traditional overlap connections.

image06

AVE Palencia-Santander HSR Package 1 (Palencia – Palencia Norte) & Package 2 (Palencia Norte – Amusco)

AVE Palencia-Santander high-speed rail project is a significant infrastructure undertaking aimed at connecting Palencia and Santander in Spain. This project involves the construction of extensive railway networks, viaducts, and bridges, underscoring the need for a strong and resilient foundation. Recognising the critical importance of ensuring the structural integrity of the concrete piles, the project management sought advanced testing methodologies.

Dextra played a pivotal role in ensuring the robustness of the project’s foundation by supplying Sonitec Crosshole Sonic Logging (CSL) testing tubes. These tubes were instrumental in conducting comprehensive structural integrity tests on the concrete piles of AVE Palencia-Santander USR Package 1 (Palencia – Palencia Norte) and Package 2 (Palencia Norte – Amusco).

Crosshole Sonic Logging is a non-destructive testing method widely employed to assess the quality and integrity of concrete piles. It involves the use of sonic waves transmitted through the concrete between two access tubes, allowing engineers to evaluate the material’s properties and identify potential defects.

Sonitec tubes are specially designed for Crosshole Sonic Logging, ensuring precise and reliable data collection during structural integrity tests. These tubes are embedded in the concrete piles during construction, providing access points for the sonic wave transmission.