India’s longest electrified rail tunnel inaugurated in Andhra Pradesh
India’s Vice President M Venkaiah Naidu recently inaugurated what is known as the country’s longest electrified rail tunnel, in Andhra Pradesh. Constructed at Rs 4.37 billion in a record 43 months, the tunnel will provide seamless rail connectivity between Krishnapatnam Port and the hinterland areas for freight movement.
This 6.6-km-long tunnel is part of the 112-km-long Obulavaripalli-Venkatachalam railway line, and is situated between the state’s Cherlopalli and Rapuru stations. As reported, the tunnel is 6.5-m-high (rail level to roof), with a minimum contact wire height maintained at 5.2 m. LED lights at an interval of every 10 m have been provided inside the tunnel. Further, two sub-stations for electric power supply have been provided near Cherlopalli and Adurupalli; an Over Head Equipment (OHE) maintenance depot has been provided at Rapuru along with tower-car shed.
The tunnel is reportedly built in the shape of a horse shoe with the New Austrian Tunneling Method (NATM). And, the track has been constructed by providing Bi-block sleepers and Vaslo fittings, thus eliminating the use of ballast.