BRIDGE OVER THE CIERVANA ESTUARY

This bridge, while of apparently normal characteristics,  was a landmark in the history of composite structures and served as a test bank for numerous innovations and subsequent developments.

This bridge was the first to employ double  composite action in areas of negative bending moments and incorporated a concrete slab connected to the bottom steel of the steel boxes which enabled large  savings in costs and launch weight due to the reduction of  steel and stiffening as the concrete prevented this from buckling.

The bridge was built by gradual launching over a   mixtilinear alignment: straight-clotoid-circumference