Thanks to all for your messages,
raseri, avier, lilo & others,
Yes you are rigth it looks like other bridges from the same author, unfortunately calatrava´s bridges tend to look alike. I particularly do not like that much this one.
About the color, yes it would look more realistic with a dirty white…
marf,
I am a bridge designer myself and I live at the moment in between dublin and madrid (spain). I have nothing to do with this bridge - The design competition was awarded to Santiago Calatrava and the construction is not even shortlisted yet. I just did it for the fun of it, as a practical example to learn how to use blender.
diago,
I did a 3D model with blender of coursel in 3 or 4 hours, as you can see here:

then I used Gimp2.0 (a GPL program pretty similar to Photoshop) to compose the render over a picture I took last week. I use as much as I can GPL software both profesionally and personally. (I actuaclly did all the
work in a Linux box
)
if you are really interested in the 3D-model you can find it here:
Macken Blender Model
Happy blender,