Lifting a load-bearing ceiling construction

SITUATION

During the rebuilding of Copenhagen's Central Station and construction of its new subway station, Johannesen Kran & Maskintransport was faced with a challenge: How to lift a load-bearing ceiling construction – consisting of 27-meter-long old wooden ceiling beams – a crucial 10 mm so that the old beams could be replaced by new steel beams. But how do you do this if the building is both old and crooked?

CHallenge

Due to the very limited amount of available space and the risk of collapse while the wooden beams were being replaced, it was important to find the right solution.

SOLUTION

The existing 27-meter-long old wooden ceiling beams that were part of the ceiling structure in the basement of the Central Station dated from before 1900. To be able to replace these beams safely, the ceiling construction had to be supported by 12-meter-long steel beams. While work was being carried out, the steel beams were supported by soldier beams that were positioned on toe cylinders.  This was done to bear the load so the ceiling construction could be lifted the crucial 10 mm, which made it possible to replace the old beams with the new ones.

The two setups, each consisting of seven toe cylinders, were controlled by two compact electric pumps that could be operated by the two Holmatro FlowPanels. This arrangement allowed the cylinders to be extremely accurately and individually operated up to the maximum pressure of 720 bar. Pressure gauges on the FlowPanels displayed the exact pressure on each cylinder, which also contributed to a safe and organized situation.

This solution is very flexible and can be used in various situations that feature a low insertion height combined with an extremely high lifting height.

Each solution set consisted of six HMJ 10 S 15 M toe cylinders (including Holmatro multifunctional cylinders) with a lifting capacity of 10 tons each, a compact electric pump (EHW 1650 RC), a FlowPanel, and Holmatro hoses. Both sets were delivered in wheeled flight cases so that the two complete sets could be easily transported to and from the work location.

Peter Rosenbäck, project manager for Johannesen Kran & Maskintransport, explains: "There is little in the old building that is entirely straight. A total of 12 adjustment points had to be lifted in order to get everything absolutely straight." He concluded, "The project was a success and went entirely according to plan. The cylinders were really put to the test and never lost pressure. Nothing at all moved, so it was absolutely perfect."

Read more about toe cylinders

View the Johannesen Kran & Maskintransport video and watch how they used our toe cylinders:

More information: FynsKran Udstyr