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| New shoring tower for use on international construction sites  The new VST heavy-duty shoring tower from PERI (VST = VARIOKIT Shoring Tower) serves as load-bearing scaffold for the large bridge and civil engineering projects. Each leg can carry a load of around 600 kN – this corresponds to about 60 VW Golfs or one Leopard-2 tank. In addition, the extremely flexible modular system can be assembled as segmental sections, towers or shoring tower frames for heights up to 40 m. As part of the VARIOKIT engineering construction kit, PERI has used multi-purpose system components also for this heavy-duty shoring tower which are completely rentable. Pins and bolts as standardised connecting parts allow simple and rapid assembly. Special components and time-consuming in situ welded structures locally are no longer required.Presented for the first time to the building industry at the PERI exhibition hall during bauma 2010, the Weissenhorn-based formwork and scaffolding specialist can now report on the first practical applications in everyday operations on international construction sites. Grand Ice Rink in Sochi, Russia The roof construction of the new ice arena in the Russian Olympic city of Sochi is supported by a total of 17 steel girders, each one up to 12 m high. These bridge the complete 94 m stadium width and have a spacing of 7.00 m to 7.50 m. Two free-standing, 37.50 m high shoring tower frame from the new PERI VARIOKIT heavy-duty shoring system serve as assembly support in the respective one third and two thirds of the length. The girders – with individual lengths of 2 x 28 m and 1 x 38 m – are pre-assembled on the ground inside the stadium itself in order that they are subsequently lifted up to their final position with the crane and connected to each other at a height of 40 m. The individual girder elements have a weight of up to 30 t. Two or three supporting shoring towers respectively with 2.00 x 7.25 m basic grid dimensions were connected at 5.00 m spacings by means of standard SRU steel walers and ties to form stable, free-standing shoring tower sections. These could be moved according to the construction progress in a longitudinal direction to the next segment. Assembly of the VARIOKIT heavy-duty shoring towers was carried out horizontally on the ground using 10 m sections. After this, these were set in an upright position with the crane and extended to the final height of 37.50 m. The dead weight of the roof steel girders resulted in point loads of 300 kN for each of the five shoring towers which meant leg loads of "only" 75 kN. The PERI solution with the free-standing VST towers nevertheless proved to be the most cost-effective variant because conventional modular scaffolding systems at such large heights would have be to be erected as spatial load-carrying constructions which is an extremely time-consuming process. Motorway bridge across the Rio Sordo, Vila Real, Portugal The 412 m long motorway bridge that spans the Sordo Valley in the north of Portugal has been designed as a five-section bridge on two separate superstructures. The pre-stressed concrete hollow box sections are being realised by means of two different construction methods: the three middle bridge segments using the balanced cantilever method and falsework for the respective edge sections. Both the superstructure formwork as well as the shoring structure are based on the VARIOKIT engineering construction kit. Support for the superstructure formwork with 10 to 25 m centre spacings is provided by the new VST heavy-duty towers. These are designed as four-legged towers with heights between 6 m and 30 m, and feature basic grid dimensions of 2.00 x 2.00 m, 2.00 x 3.75 m and 2.00 x 7.50 m – optimally matched to meet the topographical and static requirements. Up to 2, 500 kN per tower are safely transferred into the ground. Strengthening at selective points allow here leg loads over 600 kN. This clearly minimizes material requirements as well as the assembly work for the falsework. Assembly took place using variable 1.25 m to a maximum 10.25 m sections. These were delivered as pre-assembled shear frames to the construction site, extended on the ground to form tower segments and then lifted into position. Larger heights were subsequently realised through the addition of extra sections lifted into position by the crane. PERI´s Portuguese engineers combined VARIOKIT heavy-duty shoring towers with the PERI UP Rosett modular scaffold. The underlying metric grid dimensions found in both modular construction systems along with the connecting elements available in the VST system allow a perfectly matched access technology complete with stairways and ladders as well as the corresponding working levels. This has provided safe on-site working conditions resulting in a fast assembly sequence and accelerated moving procedures for all four phases of construction. write your comments about the article :: © 2010 Construction News :: home page |