Grupo Dextra | Conexões confiáveis

Túnel do Portão Oeste

Túnel do Portão Oeste

O Projeto West Gate Tunnel proporcionará uma alternativa vital à ponte West Gate, proporcionando uma segunda travessia de rio muito necessária, viagens mais rápidas e seguras e removendo milhares de caminhões das ruas residenciais.

O projeto ligará a West Gate Freeway em Yarraville ao porto de Melbourne e o CityLink nas Docklands por meio de túneis gêmeos abaixo de Yarraville e uma Footscray Road elevada.

A estrada elevada inclui 300 estacas de altura variável. As estacas foram pré-moldadas em múltiplos segmentos, próximos ao local. Barras verticais de pós-tensão unem todos os segmentos de cada estaca.

Este método de construção de estacas é cada vez mais comum mas requer uma preparação impecável, tanto na definição do método como na definição dos produtos. Cada detalhe é fundamental para o sucesso da instalação.

A Dextra forneceu à Freyssinet mais de 1.000 toneladas de sistemas Freyssibar+, grau 930/1080 MPa, com diâmetros nominais de 72mm e 55mm, e 7.500 ancoragens para aplicação vertical permanente.

Com uma estreita cooperação entre a DEXTRA, o back-office da Freyssinet (Departamento Técnico e empresa de produtos Freyssinet) e o pessoal da obra (Freyssinet Major Project e Freyssinet Austrália), o sistema de pós-tensionamento foi perfeitamente adaptado às necessidades do projeto.

Os diâmetros das barras, o tipo de aço e o desenho das ancoragens foram validados através de testes de qualificação de acordo com as Normas Australianas, demonstrando o desempenho do sistema.

Este sistema de barras pode ser utilizado para pós-tensionamento, ancoragens de solo protendidas e qualquer aplicação que envolva tirantes temporários ou permanentes, elevação, suspensão, emendas protendidas, etc.

A construção do grande projeto começou em janeiro de 2018.

Link Doha (Jaber Causeway)

Link Doha (Jaber Causeway)

 
Doha Link is a marine bridge project currently being built west of Kuwait City. It will ultimately be connected to the Main Causeway Across Kuwait Bay, another sea link project north of Kuwait City, which will make the Jaber Causeway sea link, one of the largest civil engineering projects ever built in the Middle East. The Doha Link stretches west of Kuwait City. It will ultimately solve traffic congestion and offer a direct itinerary thanks to a 7.7 km bridge structure built on shallow waters across the Kuwait Bay.  

Rebar splicing solution

A Dextra esteve envolvida na fase inicial do projeto de construção para fornecer uma solução técnica para a emenda das grandes gaiolas de vergalhões que compõem as estacas de fundação em terra e no mar. Rolltec® couplers for large diameter rebar (32, 36, and 40mm) were used for the connection of cages and piers. Two grades of rebar are used across the project: ASTM Grade 60 and Grade 80. Rolltec is compatible by design with the higher ASTM Grade 80; the same couplers may be used on all applications, simplifying stock keeping. In addition, smaller diameter couplers for rebar 12mm and 16mm were used for the superstructure and the footing of light poles. One of the main advantages of Rolltec for remote projects is its very light machine setup. Rolltec is supported by a single one-man machine, offering a high level of productivity. Because the equipment is relatively small and the rebar preparation efforts were taking place simultaneously on both sides of the sea link construction, Dextra dispatched up to 4 machines on each side of the project to support the piling efforts.  

Solução de tubo Sonitec

With large piles of 2.5m diameter and 60m depth on average, it was compulsory for GS E&C to conduct sonic logging tests to examine the integrity of concrete piles, requiring the installation of 8 tubes in each cage. To achieve very long tube length and optimize cage preparation output, Dextra Sonitec was the preferred choice of the contractor. Thanks to its lightweight and unique Push-Fit® connection feature. Sonitec provides enough flexibility during the cage construction, lifting, and assembly of the cage and removes the need for additional time-consuming welding operations.

Calçada através da Baía do Kuwait

Calçada através da Baía do Kuwait (Jaber Causeway)

 

The Main Causeway across the Kuwait Bay is a 36-km-long project currently being built north of Kuwait City. It will ultimately be connected to Doha Link, another sea link project west of Kuwait City, which will connect the Jaber Causeway sea link, one of the largest civil engineering projects ever built in the Middle East.

The main causeway across Kuwait Bay stretches north of Kuwait City. It is expected that the link will greatly contribute to the development of the northern part of Kuwait. To achieve that, the Causeway will literally cut across Kuwait Bay with a 27-km sea link.

Pilares e vigas da ponte

For the visible part of the sea link, Dextra worked with contractor Hyundai to offer high-tensile post-tensioning bar solutions.

Dextra Barra PT suave As classes 835/1050 foram usadas ao longo de toda a ligação marítima para a conexão das vigas pré-moldadas.

For part of the sea link, which is topped by a metallic cable-stayed structure. Higher performance bars in Grade 1050/1200 were used to offer a vertical anchoring point between the pylon and the reinforcement of the pile. PT Bars were delivered with a full corrosion protection accessory set by Dextra so that the bars will resist the marine conditions.

Tubos Crosshole Sonic Logging

For the concrete integrity testing of the onshore and offshore foundation piles, Dextra supplied around 400,000 linear meters of Sonitec tubes, which are easy to set up and reconnect without the need for welding, which significantly increases the productivity of the pile assemblies.

Depois de instalados, os tubos ficam firmemente no lugar, suportando sem problemas o levantamento e o manuseio da gaiola.