Comparative Study of Slab Culvert Design using Irc-112:2011 and Irc-21:2000

Reinforced concrete slab type decks are often referred to as culverts and are commonly used for small spans. Slab culverts are important hydraulic structures used in the construction of highway roads. In India, till now culverts are designed and constructed according to Indian road congress guidelines as per IRC: 21-2000 code in which working stress method is used. Recently Indian road congress has introduced another code IRC: 112-2011 for design of prestress and RCC bridges using limit state method. In regards to this, present study has been performed to know how design of IRC-112 differs from IRC-21 and an attempt is made to study undefined parameters of IRC: 112-2011 such as span to depth (L/d) ratio. Present study is performed on design of RC slab culvert using “working stress method� using “IRC: 21-2000 and limit state method using IRC: 112-2011� code specifications. It is observed that in working stress method, the allowable L/d ratio is 13 and in limit state method, the L/d ratio of 20 is most preferable. Quantity of materials required in limit state method is compared with quantity of material required in working stress method and it is found that concrete can be saved up to 30 to 35% using limit state method.