Narrow bridges

Italian technology for two bridges among 16 to come on the J&K rail link

By Quaid Najmi, Sheikh Qayoom

Mumbai, September 12 (IANS): A network of 16 bridges, large and small, including two with Italian technology – with a total length of 2.3 km – are arriving at a rapid pace on the upcoming Udhampur-Srinagar-Baramulla (USBRL) rail link, announced officials on Monday. .

The bridges are being built by engineering giant Afcons Infrastructure Ltd. Mumbai for the USBRL on the 66 km long route executed by Konkan Railway Corporation Ltd. (KRCL) to transform the lives of valley dwellers and connect Jammu and Kashmir to the rest of the country.

For the first time in India, a series of 16 Preloaded Spring Dampers (PSD) are installed on Bridges Nos. 39 and 43 to counter seismic loading and improve safety, ushering in a new era in bridge construction over land geologically complex,” said Alimilla Sagar, Afcons project manager for the 16 bridges.

Imported from Italy, the installation of PSDs will start in October and end in December, on these bridges entering Reasi, Bakkal, Kouri and Sangaldan area with works 90% complete, he added.

The PSDs are to be installed in the main span and two platform spans of the two bridges, and the Italian carpentry teams for their implementation have arrived on site.

“Additionally, a lashing mechanism is used on Bridge 30 which faces the Chenab Valley, to counter the high wind speed that will hit the structure and ensure its safety,” Sagar said.

PSDs are particularly needed for Bridges 39 and 43 as they are continuous composite steel girders with spans of 490m and 777m respectively, and could be vulnerable to any seismic wave as they are located in Reasi district, which falls within the most active seismic zone. Zone-V region, and the Reasi fault lines run through the region, he said.

PSDs are designed to counter seismic loading in structures, limiting and damping movements that occur between parts of a structure during earthquakes, help resist seismic forces and improve bridge strength and are installed directly between the bridge and the piers, according to Sagar.

For the 16 bridges, nearly 17 million cubic meters of excavation has been completed to date, 25,000 tons of structural steel and 27,500 tons of reinforcing steel and over 63,000 tons of cement have been consumed , did he declare.

Afcons Vice President for Core Methods & Engineer Group Mandar Karnik said Bridge 39 has seven piers, three over 70 meters, the highest being 103 meters or 30 meters higher than Qutb Minar.

“The foundations of the bridge are located in almost inaccessible places, the entire 490-meter-long superstructure was made of structural steel, assembled behind an abutment and gradually launched,” Karnik said.

Discussing the main hurdles, Principal Quantitative Survey Manager Ladli Prashad said these include adverse weather conditions, complex geology, extreme engineering, unexpected rains, narrow and prone roads. landslides with hairpin bends to haul heavy materials, steep slopes and frequent landslides that made hard work all the more difficult.

Despite these hurdles, Senior Manager, HSE, Subash C. Satpathy said the project achieved 17.50 million safety hours due to strict implementation of safety protocols.

Once completed, these 16 bridges will be connected to the arched superstructure of the mega-wonder Chenab Railway Bridge, which was executed in August for the USBRL project railway line to allow passengers to reach their destination safely by trains.