Leading consulting group with a 360° approach
The status on COWI's marine works for Lusail development at the beginning of 2009 is described below.
The contractor has completed the construction contract on the earthworks and marine works including variation orders related to landscaping with 5.6 mill. m³ of fill and deepening of part of the blue water area to accommodate larger boats in the outer part of the central marina.
A satellite image of the entire site is available for every month since initiation of the construction works in February 2006. The latest image and selected photos from the construction site can be found in the Take a tour of the Lusail project.
The supervision team is finalising their activities, however, key staff will be involved in the 13 months maintenance period.
The key elements of the construction works are briefly described in the following.
The Contractor constructed bunds (dikes) at the periphery towards the sea. Upon dewatering of the bunded areas the excavation works and construction of edge treatment structures were made in the dry. The excavation works were made using earth moving equipment, rock breakers and dry-blasting. Some of the bunds will remain in place until the bridges have been constructed.
The entire site was raised to a minimum platform elevation (+2.5 m MSL) taking into account tide, storm surge and global sea level rise. Surcharging with up to 3 m of fill material was used to improve the ground conditions in certain areas and vertical drains were used to accelerate the consolidation processes.
The edge treatment structures consist of revetments, block walls and stepped walls. Imported rocks were used for the armour layer of the revetments while stones for the filter layer were produced on site using the broken limestone from the excavation.
EH&S is a key issue for the construction works and is an integrated part of all supervision activities. The Contractor has to date used 11,380,000 man-hours on the project without any major accidents.