THE STRENGHENING OF DAMODAR BRIDGE ON THE BENGAL-NAGPUR RAILWAY. (INCLUDING PLATE AT BACK OF VOLUME)

D H REMFRY
1912 Minutes of the Proceedings of the Institution of Civil Engineers  
THE Damodar Bridge, situated on the Bengal-Nagpur railway about G miles from Asansol, carries a heavy coal-traffic from the Radhanagar coal-fields to Calcutta. It consists of ten girder spans of 200 feet and two spans of 100 feet, carrying a single line of 5 feet G inches gauge. The bridge was found to be weak for the newest engines and coal-trucks, which had recently been much increased in weight. All trains had therefore to be double-headed, two A class engines weighing 78 tons each being
more » ... tons each being used, and the axleloads in the coal-wagons being reduced from 16 to 14 tons each. On reaching Adra, about 25 miles from Radhanagar, one H class engine, weighing 108 tons, took on the train to Calcutta, but the loss of 4 tons of paying load in each coal-wagon continued. As the engine-loads have recently tended to increase, it was decided to bring the whole bridge up to a standard of strength 25 per cent. above that necessary for the standard maximum loadings of 1908. The two 100-foot spans were old wrought-iron Warren girders, weighing 66 tons per span, dating from 1885. They were extremely weak in their deck systems, the rail-bearers being stressed to about 10 tons per square inch. It was found quite impossibIe to strengthen these spans satisfactorily : they have accordingly been transferred to narrow gauge, and their place taken by new steel girders weighing 93.3 tons per span. A considerable amount of alteration was necessary to prepare the old girders for narrow gauge. The whole deck system had to be remodelled, the girders strengthened, new rail-bearers provided, and a wind-bracing system worked in. Nearly 10 tons of new material was used per span. The alterations were carried out in the workshop a t Damodar Bridge. Downloaded by [ University of Melbourne] on [23/09/16].
doi:10.1680/imotp.1912.16830 fatcat:kvy7cz622ngdxdnef4x26umfjy