Contractor Afcons Infrastructure Ltd used a 6.65 m (21.8 ft) diameter Robbins EPB TBM to bore through in Chennai Metro, making it the contractor's third tunnel to be bored by the machine for the project. The three separate bores for the EPB are part of an increasing trend as many Robbins EPBs have been used on multiple tunnel drives with good performance.

Robbins EPBs are built one third heavier than any other EPB in the market and are designed for 10,000 hours of usable life, making them ideal for use over many kilometers. “Robbins is known for designing resilient machines,” says Mr. Gopal Dey, Afcons Senior Manager. “For this project, we needed a machine that was specifically tailored to project conditions from soft clay to mixed ground with rock. Robbins EPB TBMs have unique design features that optimize the machine for the geology.”

Robbins EPB TBM

Robbins EPBThe Robbins EPB was originally supplied in 2012 for twin bores in weathered and highly fractured granitic rock, also part of the Chennai Metro project.
After completing its original twin tunnels, the EPB was refurbished in preparation to bore its latest 1.8 km (1.1 mi) section. During refurbishment, the inner seal greasing system was changed from auto to manual mode, and the foam nozzle system was modified. These changes optimized the machine for excavation in the highly variable mixed face conditions encountered in the first two tunnels.

The EPB was launched on February 3, earlier this year. According to contractor Afcons, the machine faced a major challenge right out of the gate. “When the TBM came out of the launching shaft, a few rings were erected, and then the machine had to cross a live railway track, which meant there would be a possibility of ground settlement,” says Afcons Director, Mr. Manivannan. “At this stage, we had to closely monitor TBM’s face pressure and advance the machine at a uniform rate to ensure proper primary grouting.” The bore’s geology mainly consisted clayey sand and about 60 meters (197 ft) of mixed ground.

Adds Mr. Dey, “We chose this machine for this project due to the underground geology in Chennai, which continuously changes from soil to mixed ground. We also liked that Robbins EPB machines are designed with active articulation to allow the machine to turn or steer with ease.”

During active articulation, thrust cylinders react evenly against the entire circumference of the tunnel lining, even in a curve - a design that eliminates the problem of tunnel lining deformation. This feature enabled the machine to negotiate through well-controlled conditions.

Robbins EPB TBMAfter completing twin bores, the Robbins EPB was refurbished for clay, sand, and rock conditions, which included a new inner seal greasing system and foam nozzle system.

With all three tunnels, Robbins field service team was on location to assist and support as required. During the course of each bore, the team advised Afcons on how best to maneuver through challenging ground and provide instruction for machine operation. The ability of the contractor and manufacturer to work well together, as Robbins and Afcons have throughout their contracts, was critical to the good advance rates. The result was a robust machine that advanced at rates of 80 mm (3 in) per minute in challenging conditions.

This latest tunnel connects multiple stations along the metro line, starting from Washermenpet through to Sir Theagaraya and to Kurukpet. The Chennai Metro Project will provide the much-needed transportation to a rapidly developing city.
Click Here
To Know More or to Contact the Manufacturer
Please let us know your name.
Invalid Input
Please let us know your Designation.
Please let us know your Contact Number.
Please let us know your email address.
Please brief your query.
Our other Value-Added Services:

To receive updates through e-mail on Products, New Technologies & Equipment, please select the Product Category(s) you are interested in and click 'Submit'. This will help you save time plus you will get the best price quotations from many manufacturers, which you can then evaluate and negotiate.

Invalid Input
Invalid Input
Invalid Input
Equipment with cutting edge technologies is making tunneling smoother at RVNL’s mega railway project and helping contractors overcome geological complexities. Sandvik’s DT 821 C and DT 922i advanced automatic

Read more ...

The Metro-Rail segment in India is growing at a frantic pace with positive long-term prospects, supported by the impetus provided by the government by way of business-friendly policies and financial support. Use of advanced

Read more ...

Lucknow Metro has achieved the distinction of becoming the fastest built metro rail project in the country - both in terms of completion of construction work and execution. On 25th November 2013, LMRCL

Read more ...

India received its first mode of modern transportation in 1853 when the first railway line was laid from Bombay to Thane to boost industrial activities and ensure easy accessibility to heavy raw materials. In the following

Read more ...

The growth of the tunnel construction in the country has been driven by a robust pipeline of projects and investments in setting up hydropower projects, developing urban mass rapid transit systems, improving road

Read more ...

Stoked by their debut success with the timely completion of Kajang Line’s underground section, Gamuda Engineering found themselves pitted once more against the unique challenges of tunnelling in Kuala Lumpur

Read more ...

A tunnelling project is a race against time and costs. Getting it right from the very beginning requires knowledge, skill and experience, as well as a proper range of equipment that fulfils the customer’s tunnelling

Read more ...

The Mumbai-Nagpur Expressway is delayed until 2022. In the meantime, a machine ‘GHH IS26’ with remarkable reliability has been specially flown in from the supplier and is in operation to help complete the project

Read more ...

The project, located at the riverside of the Moscow River, passes under heavy traffic and crowded buildings. It includes two sections of a total length of 2947m. One is from Maple Avenue Station to No.2 Working Shaft

Read more ...

Pull Force is the force that a truck or prime mover can exert onto a transporter or any type of trailer. It has been a subject of much controversy and misunderstandings as truck manufacturers and end-users often do not talk

Read more ...

The first Sandvik DT922i, a computer controlled fully automatic tunneling jumbo, has been introduced by Sandvik Mining and Rock Technology in India with a vision to achieve high levels of safety, productivity and

Read more ...

Horizontal Directional Drilling is a technology in pipe and utility installation that allows greater accuracy and flexibility in placement and ends the need for costly digging, large crews, road closures and other

Read more ...

Special knowledge is required for building tunnels and wind energy plants in order to implement demanding projects. The facilities and manufacturing processes required for such projects can be adjusted well in advance for

Read more ...

The Large Hadron Collider (LHC) at CERN is the biggest particle accelerator in the world – and growing. To equip the LHC for new, more ambitious experiments in the next decade, the accelerator is currently

Read more ...

The river has its source at over 3000 meters high in the snow-covered Andes. It reaches the Pacific Ocean after 250 km. On its way, it overcomes a considerable gradient and is, therefore, ideally suited to generate electricity

Read more ...

Tan Shunhui, Chairman, CREG, discusses the competitive advantages of the company’s tunneling equipment and solutions, emerging opportunities in developing countries, factors driving its growth and success across

Read more ...

15-meter mega Slurry TBM rolled off the assembly line at CRCHI. The excavation diameter of the equipment is 15.01 m, its total length is about 130 m, total weight is about 4300 t, installed power is about 9755 kW, rated

Read more ...

Being the longest water delivery line in the history of Jilin province, transferring water from Songhua River into Central Jilin Province will transfer the largest capacity of water and cover the largest areas. The water diversion

Read more ...

Amit Kaul, BASF India Limited (Construction Chemicals Division), India, tells about the innovative tunnel lining system and related design aspects, and also describes the main advantages of this lining system in comparison

Read more ...

Underground infrastructures are an integral part of modern cities as they serve to counter problems of surface congestion and environmental degradation. The problems of ground vibrations, vibration induced noise and ground

Read more ...

×
Sign-up for Free Subscription
'India Construction Week'
Weekly e-Newsletter on Construction Industry
Get the latest news, product launches, projects announced / awarded, government policies, investments, and expert views.