Riga-Mainz triple lift in Essen12 February 2018
Riga-Mainz used three Liebherrs, including a brand new LTM 1450-8.1, alongside an LR 1600/2 and LTM 1500-8.1, to place a bridge in Essen, completing the job with just two short overnight railway shutdowns.
Riga-Mainz had been contracted to place a 418t, 50m, steel bridge over a section of railway track. The fact that the railway had to be closed meant the job had to be completed in two night-time shifts of just three and a half hours.
Initially, the plan was to install the bridge by pushing it into position. Since, however, the bridge is a parallelogram in shape when viewed from above and spans the tracks at an acute angle, it was decided that this approach was not suitable. It was replaced by an alternative installation concept developed by Uwe Langer, managing director of Riga-Mainz.
The steel construction, assembled over the last few months on a neighbouring construction site, was transported to the site by Riga- Mainz on three SPMTs.
The construction towered around 15m above the railway tracks when the SPMT modules came to a stop near the southern abutment of the bridge.
The Liebherr LR 1600/2 crawler crane stationed at the opposite side supported around 190t of the bridge’s weight at a radius of 42m. To enable this, the crane was assembled with a derrick boom, ballast trailer and 565t counterweight. An SPMT module positioned at an angle under the other end of the bridge shouldered the rest of the 230t load. The steel construction was moved at a diagonal in this constellation, hoisted almost fully over the track and placed on two temporary pillars positioned on the same side as the crawler crane.
On the second night, the team from Riga-Mainz had assembled the LTM 1500-8.1 and LTM 1450- 8.1. With a gross load of around 110t, the 450t crane had to manage approximately the same load case as the larger mobile crane—albeit with a slightly smaller radius. Crane operator Fred Wunsch is delighted with his new crane: “Very easy to operate—just brilliant.”
In total, 530t was supported by the three crane hooks when the bridge was hoisted off the SPMT module and the temporary supports, and finally moved 6m and positioned on the abutments.