Gastel Żurawie in tandem bunker lift
By Alex Dahm14 June 2011
An historic military bunker had to be moved in Poland to make way for a new road. Crane rental company Gastel Żurawie met the challenge using a pair of lattice boom crawler cranes.
The 600 tonne capacity Terex CC 2800-1 and 500 tonne capacity CC 2500-1 were used to relocate the 464 tonne concrete bunker to allow the reconstruction of the S7 Warsaw-Gdansk highway through the village of Witramowo.
It had to be moved because the bunker, built as part of a larger military fortification, was considered by local conservation officials to be one of the best preserved examples of its kind in the country. In its new position it will be restored and opened to the public as an historical monument. It was cheaper to move the bunker than to re-route the road.
"As a particularly unique application, this lift required careful planning and the use of heavy-lifting cranes capable of operating to the high level of precision required to move the bunker to its final destination. We needed a solution that would enable us to lift, carry and rotate the entire structure extremely carefully in a single journey, without deteriorating the bunker's existing fragile condition," said Tomasz Kwieciński, Gastel Żurawie vice president.
Both cranes were assembled in SSL configuration with 42 metre booms fully rigged and ready to operate within three days. Part of the solution was a steel cage encasing the bunker designed to be strong enough to take the full 530 tonne load. In one move it was carried under hook for 70 m before being rotated into its final position.
Starting at 8 a.m., the steel frame was attached to the double hook blocks of both cranes to lift the bunker about 1.5 m above ground. The cranes then lifted, carried and slewed the load together slowly for four hours, before setting the bunker at its final destination. Double hook operation increased lifting speed, helped reduce winch reeving time and enabled the use of shorter hoist ropes to reduce the weight carried by each machine. Gastel did the job for Sando Budownictwo Polska.