|
contents | technologies | |||||||||
| Four pylons formed in weekly cycles without a crane  At intervals of 242 metres each, four bridge pylons grew steadily up to heights of 86 metres with the help of PERI ACS self-climbing technology. With a length of 970 metres, this cable-stayed bridge crosses the Fraser River and is the core element of the around 13-kilometre long six-lane highway project located near the Canadian west coast. The Golden Ears Bridge has been designed as a so-called extradosed bridge which is a cross between a girder bridge and a cable-stayed bridge. Here, the inclined cables function like a prestressing installed outside of the superstructure and are positioned at an extremely flat angle. Thus, in spite of the large spans, the pylons with a maximum height of 86 metres are much lower than a traditional cable-stayed bridge. The new route will be open to traffic in the middle of 2009 – in time for the 2010 Winter Olympic Games in Vancouver.The PERI formwork and scaffolding solution for the four H-shaped pylons is based on the modular-designed ACS (Automatic Climbing System) self-climbing technology and VARIO girder wall formwork. As a result, the continuously-changing pylon cross-sections could be cost-effectively and safely constructed using 4-metre concreting cycle heights and without requiring any crane support. The formwork concept takes into consideration here the continuous cross-sectional changes due to tapering on all sides. In addition, the pylon legs underneath the carriageway deck were to be constructed as double piers in a longitudinal direction, and as individual piers in the form of a composite construction with prefabricated steel cores for the upper half. In both the longitudinal and transverse directions, the pylons are haunched between 1.0 and 1.2 degrees. The cross-sections themselves change from a dispersed trapezoidal form measuring 5.26 m by 1.40 m and opening dimensions of five metres at the base to a single cross-section with external dimensions of 2.46 m by 5.00 m at the top of the pylon. For anchoring the ACS units to the pylon´s slanted edges, the PERI ACS system with its pivotable climbing shoe provided an extremely flexible system component. Through this, the ACS platforms can be fixed in position up to 15 degrees from the vertical axis. write your comments about the article :: © 2009 Construction News :: home page |