Swiss bearing replacement expertise

Our team in Switzerland shows its capabilities in carrying out the high-precision work required to replace the bearings of one of the busiest highway viaducts in the country – the Hammermuhle Viaduct near Zurich.

While the design and fabrication of bridge bearings to satisfy the unique conditions and requirements of any new bridge is a specialised task that requires in-depth knowledge and experience, the challenge of designing, supplying and installing bearings in an existing structure is far more complex – especially when the bridge is an important structure on a busy highway.

The design work is complicated by the need for the new bearings to precisely match the space dimensions, connection possibilities and movement/rotation needs of the existing structure as required. And once delivered to site, the installation work requires lifting the superstructure in a safe and controlled way, and often involves structural adaptation works, difficult lifting of bearings into position, and challenging access conditions – all while minimising disruption to traffic.

But having successfully carried out numerous bearing replacement projects in the past – such as the Hochheim Railway Bridge over the River Main, the Fehmarn Sound Bridge in the Baltic Sea and the “Y-Bridge” near Bischofsheim – our installation teams are well able to ensure a successful outcome, no matter how challenging the circumstances.

The Hammermuhle Viaduct near Zurich, built in 1970, is a six-lane structure of length 381 m that carries a major national highway over a road and a railway line. Having reached the end of their service life, the bridge’s main bearings required to be replaced, and mageba was selected to design, manufacture and install the new RESTON®POT bearings.

Each of the eight bearings in question had to be replaced in a series of five night shifts during which four of the highway’s six lanes could be closed to traffic. Carefully synchronised and monitored lifting of the bridge superstructure enabled the old bearings to be removed and the new ones to be inserted and grouted, and the work had to be carried out at a height of 35 m above the ground, with limited space and challenging access conditions.

Thanks to the expertise of our installation technicians and their design and project management colleagues, the replacement of all eight bearings was carried out as scheduled, enabling traffic to always resume without any delays – a key priority on all our bearing and expansion joint replacement projects.

Bridge engineer: dsp Ingenieure + Planer AG
Contractor: Marti AG
Owner: Bundesamt für Strassen (ASTRA)

The Hammermuhle Viaduct near Zurich, built in 1970, carries a six-lane national highway over a road and a railway line

The requirement to minimise disruption to traffic resulted in the bearing replacement work having to be carried out in a series of night shifts – five per bearing

Lifting the viaduct’s concrete superstructure by means of hydraulic jacks enabled the existing bearings to be removed and the new ones to be put in position

A height-adjustable platform was used to remove the old bearings and to slide the new ones into position

The new bearings were then connected to the superstructure and the substructure according to their existing connection details

Formwork was then placed around the bearing to facilitate grouting. The grouting of the bearing ensures the proper transmission of all forces to the substructure

A fully installed RESTON®POT bearing – one of the eight new bearings installed to replace the old bearings of the Hammermuhle Viaduct