Bogibeel bridge world's longest incrementally launched steel bridge: HCC

India's longest rail-cum-road Bogibeel bridge, inaugurated by Prime Minister Narendra Modi Tuesday, is not only the country's first fully-welded steel bridge but the world's longest incrementally launched steel bridge, infrastructure major HCC said.

The prime minister inaugurated the the 4.94-km-long double-decker strategic bridge, built by HCC, over the Brahmaputra river at Bogibeel near Dibrugarh in Assam.

With the width ranging from 1.2 km to 18 km, the Brahmaputra has been bridged only four times in the past, and HCC holds the distinction of building two of these bridges and has now constructed the fifth, the company said in a statement.

"Built on the Brahmaputra river in Dibrugarh district of Assam, it is the first fully welded steel bridge and the longest rail-cum-road bridge in India. HCC constructed the entire 4.9 km-long superstructure," it said.

Bogibeel bridge will provide connectivity to nearly five million people residing in Upper Assam and Arunachal Pradesh.

HCC said the project boasts of multiple benefits such as strategic and speedier access for defence forces to the Indo-China border, seamless access for medical facilities to remote north-eastern states, and most importantly reducing by nearly 10 hours the transportation distance between NH-37 and NH-52, saving transportation cost, time and fuel.

"HCC has time and again undertaken complex infrastructure projects that are benchmarks in India's infrastructure journey. Bogibeel Bridge is an engineering masterpiece, which has many technical firsts to its name. It is India's first fully welded Warren truss girder type steel bridge.

"Not only has an incremental launching technique for superstructure erection been used for the first time in India, it is also the world's longest incrementally launched steel bridge. HCC is proud to create such marvels for the nation," HCC Director & Group CEO Arjun Dhawan said.

The company said its team through sheer determination and grit completed this project, as bridging the mighty Brahmaputra has always been a daunting task.

The company said the superstructure of the Bogibeel bridge has been constructed using special copper-bearing steel plates in order to reduce corrosion.

Furthermore, due to excessive humidity in the area, a complex Corrosion Protection System specific to different components of the bridge has been implemented, it added.

To offer stability to the heavy spans (1700 MT), seismic restrainers are provided. The bridge is designed to withstand earthquakes with magnitudes in excess of 7, the company said.

The HCC Group, with a group turnover of Rs 10,132 crore, comprises of HCC Ltd, HCC Infrastructure Co Ltd and Steiner AG in Switzerland.