Investigations on simply supported concrete bridge deck slab for IRC vehicle loadings using finite element analysis

This paper presents the results related to finite element analysis (FEA) of simply supported reinforced concrete bridge deck of different span lengths (3 m to 10 m) and constant width of 12 m, with and without footpath under eleven possible Indian Road Congress (IRC) vehicle load cases. So, in total 88 no of cases were analyzed. Dimension of deck slabs are taken from standard drawings of the Ministry of Road Transport & Highways-1991. Under condition A (including footpath, carriageway-width 7.5 m), due to edge loading, maximum FEA bending moments are similar to IRC bending moments for the span up to 4 m for few cases. However, for larger spans, the IRC bending moments are less than FEA bending moments by 5 to 20%. Under condition B (without footpath, carriageway-width 9.6 m), due to edge loading, IRC bending moments are less than FEA bending moments by 4 to 30%. Under centered loading, the IRC bending moments are similar to FEA bending moments for span up to 4 m under few cases and less than FEA bending moments by 4 to 23% beyond 4 m. As per IRC, one lane of Class-70R or two lanes of Class-A and one lane of class-70R with one lane of class-A or 3 lanes of class-A are to be considered as design live load for condition A and B respectively. FEA result agrees with IRC for condition B but FEA design bending moment occurs under IRC Class-AA Wheeled load or Tracked load for condition A.