All inclusive

The comprehensive range of bridge products and associated services offered by mageba is demonstrated on a current highway structure renovation programme in Switzerland.

A stretch of highway to the south of Zurich, not far from mageba’s headquarters, is currently being renovated after several decades of service, in a project that began in 2017 and is expected to run until 2022. Since approximately four kilometres of the highway’s total length of 21.1 kilometres is carried by bridges and viaducts, the project presented a great need for structural bearings and expansion joints. But the responsible engineers were not just looking for a manufacturer to supply these key bridge components; they wanted a specialist partner that would support their project from start to finish, recognising the value this would have in minimising costs, effort and impacts on traffic in the years to come. We are proud to have been entrusted with this responsibility, and pleased to be given the opportunity to show how mageba’s wide range of bridge component products can meet the diverse needs of virtually any project, and how our comprehensive range of services can help ensure that the ideal components are used optimally.

The project required 568 structural bearings in total, including 343 RESTON®POT bearings and 225 LASTO®BLOCK deformation bearings, as well as TENSA®CRETE expansion joints (featuring noise-reducing surfacing) on several structures. But mageba’s involvement on the project began long before fabrication work started in two of the company’s European factories. Our sales and technical specialists were happy to provide comprehensive advice already in the early stage of the programme, assisting with the selection of optimal approaches and component types, and with the development of project-specific solutions. After the award of the contract, our designers proceeded to design and detail structure- and location-specific solutions, considering in particular the need to install the new components to replace the existing old ones – an especially challenging need in the case of the bridge bearings, considering the very limited space available beneath the existing superstructures. Following approval of each design, and fabrication and delivery to site, the components are currently being installed by mageba, working together with the main contractor. And finally, after completion of installation, our staff can sign off that all components have been properly installed, with recording of all appropriate details and measurements – ensuring good long-term performance, giving peace of mind to the owner, and providing the data needed for future inspection and maintenance work.

So let us be your “one stop shop”, meeting all your project’s needs in relation to key structural components – including not only structural bearings and expansion joints but also hydraulic dampers and STUs, seismic protection devices, automated monitoring (SHM) systems and other highly engineered solutions. We will be happy to be your partner throughout your project, from initial selection of optimal solution to final confirmation of proper installation.

Roughly 20% (3.9 km) of the total 21.1 km length of the stretch of highway is on bridges and viaducts, requiring 568 replacement bearings to support the superstructures

A typical bridge bearing requiring to be replaced – with minimal intrusion on the existing concrete structure

All structural bearings are suitably designed to enable them to be easily connected to the concrete structures above and below by simply drilling holes for anchors from the side (overcoming the difficulty of drilling vertically considering the space limitations)

The bridge bearings that are designed to prevent horizontal movements are equipped with a “fuse feature” which will enable the steel elements that provide this horizontal fixity in normal service conditions to “fail” at the appropriate high load arising during an earthquake, by shearing off special screwed interfaces – minimising damage and protecting the structure and its users

This LASTO®BLOCK (Type NBf) bearing has a simple elastomeric bearing at its core and steel fittings to prevent movements in any direction (except as allowed by the fused connection during an earthquake)

This elastomeric bearing, of the LASTO-BLOCK (NBa) type, allows movements in all horizontal movements in service and therefore does not require a fused connection to facilitate seismic movements

This RESTON®POT bearing is also equipped with “fused” elements which will fail when exposed to the large movements (and forces) arising during an earthquake

The steel channel sections used to connect this bridge bearing to the substructure (with horizontally drilled anchors) have been grouted to ensure proper transfer of forces and long-term durability

Lifting each new structural bearing into position under the superstructure presents its own unique challenge

The bearing replacement work is being carried out by experienced mageba installation staff, ensuring that every bridge bearing will be able to provide proper long-term performance