Jacks lift Steel Girders for Europe’s largest Lift Bridge into Position
As an integral part of the construction of the A 15 Motorway from Maasvlatke to Vaanplein in the Netherlands, the new Botlek Bridge was built as a new element of the 37km long route.
The new lift bridge rests on three oval concrete pillars on which two 64m high reinforced concrete lifting towers were erected in pairs. At the 6 reinforced concrete towers, tensioning ropes mounted to counterweights run over large wheels towards the most important cross girders of the bridge structure. The two-part bridge system includes two separate steel decks measuring approx. 94 x 50m each that were floated into position using barges and lifted into position from the water.
When in operation, the bridges can be lifted or lowered by 30m in less than 100 seconds in order to permit the passing of large ships.
Due to their comprehensive know-how and technical competence, the company Waagner-Biro AG headquartered in Vienna, Austria, was awarded the contract for the extremely complex bridge drive system.
The first lifting of the bridge was a special challenge. The bridge and the counterweight basically have the same weight.
Despite this, there was an imbalance towards the bridge during the first lifting. Consequently, the flying shores on which the counterweight had been concreted had to be lowered during the first lifting operation. This measure resulted in an alteration of the complete static system, which is why the anchors had to be retensioned simultaneously during the lifting procedure. That is why 16 jacks with hydraulic pumps that could be used simultaneously were needed for the lifting process.
Waagner-Biro AG asked DSI Austria to supply the necessary jacks and hydraulic units. DSI Austria cleared the availability of the needed jacks and pumps with their colleagues in the Netherlands and in Germany because the simultaneous use of 16 jacks posed a technical challenge. Lead-managed by DSI Austria, all 16 jacks and hydraulic pumps were sent to Rotterdam on schedule. In addition, DSI Austria also supplied 550m of Type WR, 26.5mm Ø DYWIDAG Post-Tensioning Bars with 32 couplers, 64 nuts and 64 solid steel plates.
On site, the colleagues from DSI Netherlands supported the jobsite during the instruction on how to assemble the jacks and hydraulic units as well as during the lifting procedure.
Thanks to the excellent co-operation between the jobsite and the participating DSI units, the lifting procedure could be realized according to plan and to the full satisfaction of the owner.