In Civil Engineering (Bridge Design), The design of a simply supported skew bridge, which direction of reinforcement should be provided?

The skew bridge is reinforced by2 sets of rbars as following:-

 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.

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.

Agreed with all experts good answer from all of you, thanks for sharing the knowledge. 

I found the same answer than Mr. Alex Yazouri on Posted in Bridge Engineering and therefore have to agree with the  answers already given

A skew bridge gets the normal rebar based on mechanics , but don't forget the torsion rebar! And also the check shear combined with torsion

As a rule of thumb, there will be moment spanning in  both orthogonal directions on the bridge. Consequently, rebars are needed in both spans.The more the moment, the more the flexural rebars needed.

The torsion and the shear will also be checked as earlier mentioned. I'll be surprised if you ever find a one way spanning reinforced concrete bridge deck! The weight and size would make that impossible.

Flexural Main bars in long direction and secondary in opposite direction.

Thanks for invitation....I endorse Experts answers

Skew bridge has oblique arc and that means that it reinforces the vertical powers.

Main Bars at normal width and distribution bars at skew length