Lift and transport service provider Toggenburger used two Terex lattice boom crawler cranes to lift an 884 tonne bridge in Schafisheim, Switzerland.
The bridge was lifted between two buildings at the Coop distribution centre in Schafisheim. To lift the 163 metre bridge, Toggenburger used a 400 tonne capacity Terex CC 2400-1 and a 500 tonne Terex CC 2500-1, both lattice boom crawler cranes.
The CC 2400-1 was set up in an SSL configuration with a main boom of 48 m, a counterweight of 160 tonnes, a central ballast of 40 tonnes, and an SL counterweight of 240 tonnes. The CC 2500-1 was configured almost the same, except with an SL counterweight of 250 tonnes. A 130 tonne capacity telescopic hydraulic crane was used to assist.
Space restrictions meant that the two-level bridge was lifted in sections. At the site, the components of the bridge were welded into seven bridge elements. These were then placed on the bridge’s three piers in five lifts, a spokesperson explained.
André Huber, Toggenburger project manager, said, “The individual bridge components had enormous gross weights of up to 275 tonnes and required us to use working radii of up to 29 metres, which made it absolutely necessary to use the largest crawler cranes available in all of Switzerland – our Terex CC 2400-1 and CC 2500-1 duo.”
To pick the pieces of the bridge up, special yokes were fabricated, which made it possible to attach hoist cables to the sections with shackles and help with the bridge alignment. Two pieces of the bridge were lifted together, with one element being rigged to one of the two cranes while the other crane supported an arrangement with 140 tonne strand jacks placed at three rigging points between the hoist cables and the yoke. The strand jacks made it possible to control the lateral and longitudinal position of the second element using a hydraulic power. Genie aerial work platforms were then used to rig the load-securing equipment.
Michael Dudler, Toggenburger project manager, said, “Despite the sophisticated setup we had for manoeuvring the loads, we were a little worried, because any strong winds would have prevented us from performing the lifts.”
The Terex CC 2400-1 crawler crane started off the lifts at a working radius of 18 m. The first two sections to be lifted weighed 275 tonnes and measured 55.5 m each. They were lifted to a height of 12 m before being placed onto the bridge piers. The first piece lifted by the CC 2500-1 was 41 m long and weighed 250 tonnes. A modular trailer was used to move the bridge section into position for the CC 2500-1.
The CC 2400-1 was then used to lift the fourth bridge section into position. The section was 22 m long and weighed 95 tonnes. It required load-securing equipment weighing 20 tonnes and was lifted at a radius of 29 m. Two of the remaining elements of the bridge were nearly 49 m long and had a gross weight of 240 tonnes. The CC 2500-1 was used to lift the pieces into position at a working radius of 25 m. The final bridge section weighed 17.5 tonnes and was installed using the assist crane.