Illsteg

The local conditions and requirements generated a design of the Ill passage as a beam and slab bridge in framework finishing. It is suspended on the bearings above the ground and has the elegance and lightness of a pedestrian cyclist bridge. On the town side, three ramp-like sloping concrete slabs connect the square with the bridge and fan out to steps, forming a three-sided accessible bridge head.

A spacious framework construction with a triangular section of steel was chosen as a support system. The upper flange has been designed as an orthotropic slab and serves as a footpath.

The slab consists of two metal layers with a reinforcing grid made of right-angle hollow sections between them. Its dual function and the reduction to the minimal slab thickness required by the static give the construction a filigree appearance and optimise the use of the material.