Curved Bridge Deck

[Catjacob]

For the purpose of preliminary design, is there any simple equation which can be used to work out the torsional moment of a curved bridge deck (in plan) if both ends are torsionally restrained.

What I know is that the BM on the bridge is approx equal to w x (arc length)^2 /8.

Another equation I know is dT/ds = - (M/r + ...-->minor terms)

 

[edward1]

Is curved beam slab what you are designing? If so and bridge is at least 2 lanes wide and not a very small radius,
this is not big factor. The torsion will be taken out by the full width slab cross section.