In the design of a simply supported skew bridge, which direction of reinforcement should be provided?

In the design of a simply supported skew bridge, which direction of reinforcement should be provided?
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Answer :

In the conventional design of steel reinforcement for a simply supported skew bridge, a set of reinforcement is usually placed parallel to free edge while the other set is designed parallel to the fixed edge. However, this kind of arrangement is not the most efficient way of placing the reinforcement. The reason is that in some parts of the bridge, the moment of resistance  is  provided by an obtuse angle  formed by the reinforcement  bars  which is ineffective  in   resisting  flexure.  In  fact,   the  most   efficient   way  of  the  arrangement   of reinforcement under most loading conditions is to place one set of bars perpendicular to the fixed edge while placing the other set parallel to the fixed end as recommended by L. A. Clark (1970). In this way, considerable savings would be obtained from the orthogonal arrangement of reinforcement.
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