Design And Construction Of A Geofoam Embankment Over Soft Ground

Development of the new Service Centre required construction of an off-ramp from the existing road together with an internal road network. Together these will provide access to the Service Centre for traffic from the existing roads. The off-ramp and road network were constructed on fill embankments, up to 4m in height, overlying a relatively uniform but very significant thickness of soft clay. In addition, the project site had been subject to a complex history of loading and unloading as a result of previous development on the site and ground improvements adjacent to the site, as part of new Service Centre development. To mitigate the effects of post-construction settlement to acceptable levels, safe and cost-effective ground treatment measures were developed along the preferred road alignment.

This paper provides some background to the project and presents in detail the design and construction methodology adopted for the lightweight fill treatment works using geofoam. The new geofoam embankment had to be constructed within the vicinity of existing and new infrastructures, i.e. pile-supported bridge, existing roads and a new drainage structure.