JAPAN BRIDGE

Japan Bridge spans 103m across the motorway to the west of La Defense in Paris. A simple tied arch with a suspended glass tunnel to protect users from inclement weather, it was built for the client Sari and named in honor of its architect, Kurokawa, and of the client’s development partner, Mitsubishi.

The arch itself is fabricated in steel plate, and its ends are linked by a pair of solid-rod steel ties, positioned to limit lateral thrust onto the buildings located at either abutment. The suspended bridge deck, which appears to float through the arch,is supported off a series of struts that spring off the lower tie rods at regular intervals. The arch shape is stabilised in-plane by the regular placement of suspension cables whose tension is maintained by the deck mass, thus enabling the arch profile to trace a very fine silhouette.

The deck is sheltered by a glass tunnel made up from curved glazing supported off stainless-steel members, with ventilated joints to avoid excessive heat build- up. Aerodynamic considerations were important on this project, as the layout of neighbouring buildings leaves the footbridge greatly exposed to wind accelerations due to the Venturi effect. In response, the shape of the glass tunnel roof was rounded-off in order to mitigate lateral and torsional wind loading on the bridge.
Hugh Dutton collaborated closely with Peter Rice on the structural design development of Japan Bridge, whilst working with the engineering firm RFR. The structure was analysed at Ove Arup by Pat Dallard.