デクストラグループ |信頼性の高い接続

チェンナイ地下鉄

チェンナイ地下鉄

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.

リオ地下鉄4号線

リオ地下鉄4号線

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.

ナグプール地下鉄、リーチ-1 (1 号線)

ナグプール地下鉄、リーチ-1 (1 号線)

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.

ドーハ地下鉄、ゴールドライン – Al Sadd C-Ring駅

ドーハ地下鉄、ゴールドライン – Al Sadd C-Ring駅

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.

第2回ホーチミン市環境衛生

第2回ホーチミン市環境衛生

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 (GFRP) Soft-Eyes were applied to reinforce 21 shafts, allowing penetration by the Tunnel Boring Machine (TBM) without the need to remove steel reinforcement 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.

Doha Metro Rail – Phase 1

Doha Metro Rail – 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)

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.

Cairo Metro – Line 3

Cairo Metro – Line 3

Since the first 29km segment of the Metro Line 1 opened in 1987, the Cairo Metro project has revolutionized the transit system in the capital.
Currently the whole network comprises 3 operational lines numbered from 1 to 3. Line 3 consists of four phases, and the first segment started operation in 2012.

Three new metro stations were opened as part of the fourth phase of the third line on June 15, 2019, a week before the kickoff of the 2019 African Cup of Nations (AFCON) in Cairo.

Dextra has continuously provided construction solutions since the operation of Line 2 in 2000, delivering since then more than:

-1,400,000 rebar couplers

-7,000 sonic tubes

-60 soft-eyes

Bartec rebar couplers are used for rebar reinforcement of tunnel and station structures on both underground and elevated metro lines as a way to reduce steel congestion and improve tensile connection.

Moreover, the integrity test of the metro foundations using the Cross Sonic Logging (CSL) testing method was facilitated by the usage of SONITEC sonic tubes, designed for easy assembly and installation in reinforcement cages.

Dextra’s ASTEC soft-eyes are made of GFRP rebar to reinforce D-Walls in underground tunnels, which can easily be cut by Tunnel Boring Machine (TBM), resulting in time and money savings.

The project is still ongoing and the fourth line of the Cairo Metro is expected to start operation in 2020.

地下鉄ナーグプール駅、地下鉄ゼロマイル駅

地下鉄ナーグプール駅、地下鉄ゼロマイル駅

マハーラーシュトラ州ナーグプール市で行われている交通機関/駐車場/商業複合プロジェクトのナーグプール地下鉄ゼロマイル駅。市内を北から南に横断する新しい地下鉄線上にあります。ゼロ マイル ステーションは、商業エリアと 430 台収容の駐車場を備えた 12 階建ての建物を組み合わせた地下鉄駅です。

このプロジェクトでは、デクストラは 2017 年に、掘削エリア周囲の地盤を安定させるためのグラウンド アンカーの供給と設置に参加しました。

Dextra は、革新的な ASTEC (FRP) アクティブ アンカー ソリューションを提供しました (AAA)、一時的な用途の場合、たとえ敷地境界線を超えて伸びていたり、将来のトンネルにぶつかったりしても、プロジェクト終了後に地面に残すことができる特別なタイプのグラウンドアンカーです。

実際、FRP アンカーバーの主な利点の 1 つは、アンカーを従来の掘削装置で完全に切断できることであり、最後に力任せに地面から取り外す必要がある鋼製アンカーである従来の取り外し可能なアンカーの最良の代替品になります。プロジェクトの。

Dextra ASTEC アクティブ アンカーは持ち運びが軽く、作業員が最終的な場所まで運ぶことができます。ドリルで開けられた穴に挿入されると、各アンカーにグラウトが注入され、その後 FRP アンカーに接続された従来の PT ストランドを使用して応力が加えられます。追加のプロジェクト管理が必要であり、耐用年数が終了したアンカーの撤去費用が発生する従来の取り外し可能なアンカーとは異なり、設置後もアンカーを地中に残すことができます。

インドにおける Dextra アンカリング ソリューションの詳細については、弊社までお問い合わせください。 ムンバイ事務所.

ホーチミン市地下鉄 – 1 号線 (ホーチミン市地下鉄、ベトナム)

ホーチミン市地下鉄 – 1 号線 (ホーチミン市地下鉄、ベトナム)

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).

大量交通システムが実現すると、ホーチミン市地域は地下鉄6路線でカバーされ、住民や観光客が市内を簡単かつ便利に通勤できるようになり、都市生活の質が向上します。

プロジェクトの第 1 段階では、ベンタイン市場とスオイティエン公園を結ぶ 19.7 キロメートルの鉄道線の建設が行われます。 11駅を含む17.1キロの高架鉄道と、3駅を含む2.6キロの地下線の建設も含まれる。

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

設置はコンパクトアンカープレートを補強バーの先端にねじ込むだけです。このソリューションにより最終的にプロセスが容易になり、コンクリートの品質が向上します。