Crane trio lifts railway bridges

Construction contractor Adolf Lupp, awarded the job to Eisele, who brought Riga Mainz on board as a partner.

The bridge structure, which consists of two separate steel bridges, routes a single track over a double track section operated by Deutsche Bundesbahn. Both bridges measure 40m in length, 13.65m in width, 5.3m in height and weigh 160t.

For the refurbishment work, the two steel structures had to be positioned on 1.5m high concrete elements on a nearby asphalt surface. As the mobile cranes were unable to access this area, the bridges were hoisted out and then loaded onto SPMTs. The six-axle heavy duty modules then transported the components to the intended position with the unloading operation being carried out by the SPMTs’ hydraulic systems.

The position of the first bridge and the fact that it had to be hoisted over a 12.9m overhead cable mast, posed a major challenge. Riga Mainz’s new LTM 1650-8.1 and Eisele’s LTM 1500-8.1, both ballasted with 165t of counterweights, were used together to carry out the first hoist.

The LTM 1650-8.1, with its telescopic boom extended to a length of 33.8m, hoisted a weight of 88.2t at a radius of 19.1m. The remaining 85t were hoisted by the LTM 1500-8.1 using its 31.7m telescopic boom at a radius of 16.4m.

Whilst hoisting out the second steel bridge, the LTM 1500-8.1­—which was standing in the middle—worked with an LTM 1450-8.1 from Riga Mainz, fitted with 134t of ballast.  The 450t crane had to manage a load of 85t on its 31.9m telescopic boom at a radius of 15.5m. The third crane was required as it was not possible to move the cranes around the site between hoists due to a lack of time.

The steel structures are currently being refurbished. Large mobile cranes are scheduled to return this autumn to hoist the two bridges back into the original positions.