I like the simplicitiy of the colours here, only the grey of the concrete and the rusty orange/brown on the reinforcements. The perspective is also interesting as is the aperture and thus your choice of DOF ... I don't understand, though, how the foremost band of steel (second of the two) can be blurred at the back of the top and have a sharp part towards the front?
The very important, yet still unmentioned element to this photo is, of course, the puddle! And the reflection it gives you!
What are they building, and where? And how did you get to be there?