Title : ARCHITECTURAL AND DECORATIVE CONCRETE
Authors : Dr. Manamohan R Kalgal Head, Technical Service, UltraTech Cement Ltd, Mumbai, India, Email: mkalgal@gmail.com
Publication : December 19-21, 2013
Volume :
Pages : 66-73
Price : 250
Abstract : The project of Bangalore?Hosur Elevated Expressway comprises 10 km of elevated viaduct, a complex traffic interchange, two flyovers, several vehicular and pedestrian underpasses (VUPs and PUPs), as well as ground level roads. The elevated viaduct has been constructed using a precast segmental superstructure continuous over the spans (29m+6×34m+29m = 262m), constructed in 8 stages viz 1¼ span, ¾+¼ span, ¾+¼ span, ¾+¼ span, ¾+¼ span, ¾+¼ span, ¾+¼ span, ¾ span. The analysis and design had to carefully simulate the structural model to account for stagewise prestressing, hyperstatic effects and creep redistribution, apart from the applicable primary loading. The sharply curved interchange superstructure has been conceptualized as a cast-in-situ RCC voided slab with spans ranging between 20 and 35 m. The two flyovers are comprised of a continuous girder-slab superstructure incorporating precast post-tensioned girders. The VUPs and PUPs have been constructed using the Box Pushing method. Speed of erecting superstructure for each span of the 262m long module was about 3½ days. As the single box girder carried two carriageways, the speed is said to be 1.75 days per carriageway span. Main attributes to the speed of construction were the use of wireless remote controlled launching girder, matching speed of production of precast segments produced using short bench method, prefabricated reinforcement was used to speed up the precasting process. Adequate number of trailers were employed for transportation.