For the first time, a cable-stayed bridge is set to break the 1000 meter (m) span barrier. The six-lane Sutong Bridge also sets a new benchmark with its two Ashaped pylons, whose height of 306 meters is unprecedented. All in all, a great challenge for contractor CHEC Construction and for formwork manufacturer Doka, which is supplying the climbing technology.
The world-record span of 1088 m requires A-shaped pylons 306 m tall. And the speed with which work is progressing on the A-shaped legs of the pylons is just as record-breaking as their height. Both legs are rising toward the point where they will meet by two 4.5 m sections each week. The driving force behind this swift yet safe growth is the 36 Doka automatic climbers at either end of the bridge. These have the job of executing as many as 68 casting sections on each pylon.
The automatic climbers make for an efficient, crane-independent construction workflow. Being anchored to the structure at all times, and with their working platforms enclosed on all sides, they also offer a high level of safety.
The largely automated climbing operation runs with the aid of powerful hydraulic units and can be carried out independently of the prevailing weather conditions. The whole operating sequence runs smoothly even with wind speeds as high as 70 km/h. The structure is being erected in a region that is regularly hit by typhoons, so has been designed to withstand the very highest wind loads.
The world’s tallest tower crane is being used for the building work. The concrete is pumped up into the formwork by powerful pumps supplied directly from an on-site concrete plant set up on the pylon island.
The new bridge will take traffic across the 6-km-wide Changjiang River starting at the end of 2008, cutting journey times by 55 minutes. To date, it has only been possible to cross the river by ferry. The Changjiang River is a busy waterway, hence the bridge’s generous shipping clearance profile of at least 891x62 m. The 8146 m long bridge construction will be part of the national motorway network linking the two giant cities of Shanghai and Suzhou.