Mumbai-Ahmedabad Bullet Train: Another Milestone as NHSRCL Erects First Steel Bridge, 27 More To Go

A day after the National High Speed Rail Corporation Limited (NHSRCL) announced that it has completed the first mountain tunnel in a short span of 10 months for the Mumbai-Ahmedabad High Speed Rail Corridor (MAHSR), also known as the bullet train project, they have now said that the first steel bridge, which is 70 m long, has been erected in Gujarat.

In a statement issued on Friday, the NHSRCL said that the steel bridge is across National Highway-53 in Surat.

“This is the first of the 28 steel bridges which will be part of the MAHSR corridor. Approximately 70,000 MT of specified steel is estimated to be used in the making of these steel bridges. The length of these steel bridge spans varies from 60 meter ‘simply supported’ to 130 + 100 meter ‘continuous span’,” it said.

THE PROCESS

The making of steel bridges undergoes high-tech and precise operations of cutting, drilling, welding and painting as per the design drawings prepared by Japanese engineers.

A contractor is mandated to employ welders and supervisors certified by International Welding Experts. The welding process is also monitored by the Japanese International Welding Experts stationed at each workshop. A fabricated structure undergoes a check assembly process. And then follows the sophisticated five-layered painting of the steel structure.

Prepared at the workshop in Hapur, around 1,200 km from the bridge site, the steel structure was transported on trailers to the site of installation. It consists of nearly 700 pieces weighing 673 metric tonnes.

At the site, the steel bridge of 12-14 meter in height was assembled on the staging above 10- to 12-meter-high piers.

“Thereafter the launching nose of around 200 metric tonnes weight was assembled with the main bridge assembly. With massive care and expertise, the bridge assembly was pulled to its intended span through a specially designed pulling arrangement under the complete traffic block on National Highway,” the body added.

Each production batch of steel was tested by Ultrasonic Testing (UT) at the manufacturer’s premises.

WHY STEEL BRIDGES?

Steel bridges are most suitable to cross highways, expressways and railways lines, unlike pre-stressed concrete bridges, spanning 40 to 45 meters, which are suitable for most sections, including river bridges.

“India has the expertise of fabricating steel bridges for heavy haul and semi high-speed trains which run between 100 and 160 kmph. And, this is for the first time, a steel bridge to support a Shinkansen Bullet train running at a speed of 320 km per hour was fabricated and successfully launched with precision,” NHSRCL, the body undertaking the construction work of the project, said.

BULLET TRAIN PROJECT

The work on the country’s first bullet train started in September 2017 in Ahmedabad, Gujarat. Prime Minister Narendra Modi and former Japanese Prime Minister late Shinzo Abe jointly laid the foundation stone for the project.

The total cost of the MAHSR project was estimated as Rs 1,08,000 crore in 2015. However, the final project cost will be ascertained only after completion of land acquisition, finalisation of all contract packages and associated timelines.

High-speed trains on the Mumbai-Ahmedabad High Speed Rail Corridor will operate at a speed of 320 km/hour covering a distance of 508 km and 12 stations.

The total length of the bullet train corridor is divided into three states/UTs – 156 km in Maharashtra, 4 km in Dadra and Nagar Haveli and 384 km in Gujarat.

There will be 35 trains per day in one direction, with a frequency of 20 minutes in peak hours and 30 minutes in non-peak hours.