The Sutong Cable stayed bridge currently under construction in China will be the longest spanning cable stayed bridge in the world when completed in late 2007. The bridge has a main span of 1088m and crosses the Yangtze river approximetaly 100km inland from Shanghai. The steel orthotropic deck for the bridge has been fabricated offsite and is being delivered by barge to the bridge site in 16m long segments weighing up to 450 tonnes each. The delivery barges are moored in the river below the bridge and the deck segments are being lifted to final height and aligned with the previously erected deck segment by eight purpose made deck erection gantries . DLT were sub-contractors for the design, supply and site supervision of these deck erection gantries, to main contractor 2nd Navigation Engineering Bureau. The first deck segement was erected on 9th November 2006, an operation which included a 125% overload test and a 110% dynamic test. The last segment was erected on 9th June 2007.
The contract for design and supply of these deck erection gantries was
let by international tender, under the control of an independent government
tendering agency and subject to the recommendations of a panel of Chinese
experts. The hydraulic and electrical components for the gantries were
manufactured in Europe and shipped to China, where they were be assembled
onto fabricated steel frames made in China.
The gantries work in pairs to
lift and align the deck units. Each gantry has one 290 tonne capacity
DL-S290 strand jack to lift the deck unit and a system of secondary hydraulic
rams to carefully adjust its final plan position and slope so that it
can be accurately fitted to the previous deck segment for welding, to
within a tolerance of +/- 1mm. The hydraulic systems on each pair of gantries
are monitored and controlled by a single operator using the recently developed
DL-P40 computer control system which ensures accurate synchronisation
of the strand jacks and simple and failsafe operation.
To download a full animation of the gantry working cycle please right
click on the following link and select 'Save target as....' to download
the file. Down
load animation (61.2mb). You may find that you need to install the
DivX6 codec to view the animation. Download
DivX6 codec (8.91mb).
DLT has previously been responsible for lowering of a 3050 tonne steel cofferdam on this project, using 16 No DL-S418 strand jacks monitored and controlled by the same DL-P40 computer control system that will be fitted to the deck erection gantries. More>
More details of the Sutong bridge project can be found at http://www.stbridge.com.cn