EFFECTS OF SKEW ANGLE ON BENDING MOMENT'S DISTRIBUTION IN THE SKEW BRIDGE DECK

Abstract

In this paper the effect of skew angle on reinforced concrete skew bridges deck is presented by using the grillage analogy. The actual decking system of the bridge is represented by an equivalent grillage of beams. A span 24 m of simply supported right bridge deck with I-section prestressed concrete girders is taken as the case study to obtain the values of the bending moment's distribution for the two types of skewness (types 1 and 2) and the results of skew types are compared against the moments of the right deck span of the bridge. In the skew type 1 the deck span is increased as skew angle increased while in type 2 there is no increase in the desk span. The analysis results for the span are obtained dead and live loads (Iraqi standard load and walkway loading) using STAADPRO computer program. The analysis provided useful information about the variation of moments with respect to change in skewness. It is concluded that in skew bridge deck, the bending moment is increased with increasing the skew angle in skew type 1 while it is decreased with increasing the skew angle in skew type 2 and the negative bending moment in transverse direction and the torsion are increased.

Keywords

• Skew bridge deck, grillage analogy, bending moment, standard Iraqi load