ENERPAC helps the Beijings Birds Nest to stand
Beijings National and Olympic Stadium
During construction, the crisscrossed interwoven steel roof construction of the bird’s nest roof was supported by 78 temporary steel columns. For additional stability, the huge ‘twigs’ were welded onto the supports. After completion of the bird’s nest construction the ‘twigs’ had to be cut off the support piers, before dismantling of the piers could start. Basically the disconnecting and dismantling process of the temporary supports comes down to synchronically and fully controlled lifting the structure of its supports, cutting the welds, followed by controlled and synchronized stage-lowering to allow the removal of the 50mm think leveling plates that were used during construction. Enerpac was granted the contract to perform the stage lifting and lowering of the roof. The design of the bird’s nest is based on three construction circles; an outer circle, a central circle and an inner circle. Each circle has supporting piers. For load, control and accuracy reasons the 78 support points including their hydraulic systems are divided into 10 regions. For the actual stage lifting and lowering process each support pier is equipped with two 150-ton cylinders. After successful disconnecting steel structure from its temporary piers, the bird’s nest stood on its own “feet”.
