New Delhi: Prime Minister Narendra Modi is all set to inaugurate Asia’s second longest rail-cum road bridge, Bogibeel in Assam on Tuesday. The bridge has a functional period of around 120 years as per senior officials. Here what is special about Bogibeel Bridge: -The 4.9 km-long Bogibeel Bridge on the Brahmaputra river is India's only fully welded bridge for which European codes and welding standards were adhered to for the first time in the nation. -The bridge, constructed at an estimated cost of 5,800 crore rupees, has a "serviceable period of around 120 years.The bridge has a two-line railway track on the lower deck and a three-lane road on the top deck. -For the first time in Indian Railways, the girder has steel floor system for railway tracks and concrete for road. -The bridge will reduce travel time from Assam to Arunachal Pradesh to four hours and will cut out the diversion of over 170 km via Tinsukia. -It will also reduce Delhi to Dibrugarh train-travel time by about three hours to 34 hours as against 37 hours presently. -After inaugurating the Bogibeel bridge in Dibrugarh, Prime Minister will travel to the other side of the river to deliver his key note address at a public rally in Dhemaji.