A fleet of four Dynapac CA602D single drum soil compactors is currently working at Muscat International Airport in Oman to compact approximately 160 sq km of rockfill as part of a major development of the airport complex.

The initial phase of development is designed to increase the airport's passenger handling capacity from the current 5 million/year up to 12 million by 2011.

As the first part of the project, the grounds are being raised by 3 m to prevent the new runway and the new roads ending up under water, after the rare, but severe rainfall.

This is being done by transporting 10-12 million m3 of desert sand and crushed rock onto the site, said a company executive.

The 19 tonne Dynapac rollers are being used by local contractor Galfar Engineering & Contracting SAOG to compact approximately 160 sq km with five layers of rockfill, each having a thickness of 550 mm with compaction meter values (CMV) of 21 for the initial layer and 55 for the remaining four layers, all achieved with eight passes.

Once the rockfill has been compacted, an additional 1.3 m layer of subgrade, asphalt and concrete will be added to provide runways, taxiways and aprons capable of handling the Airbus 380, the world's largest passenger aircraft.

The rollers are equipped with Dynapac's Compaction Analyser system (DCA) which not only gives the operator a continuous read-out of compaction values but also indicate precisely which areas require additional compaction.

On this project the DCA is further enhanced with GPS which shows the position of the roller in relation to a selected reference line.

The analysis function also enables the compaction work to be replayed if required to assess if the roller has been used efficiently and to see which CMVs have actually been achieved.

The important information provided by these on-board systems has been much appreciated by the surveyors working for the main consultant, Cowi-Larsen JV, which is undertaking the whole project on behalf of Oman's Ministry of Transport & Communications.

Powered by a Cummins turbocharged diesel engine developing 142 kW (190 hp) @ 2200 rpm, Dynapac's 602D roller is designed for the toughest applications, having an ability to compact rockfill in layers of up 2 m thick with individual rocks as large as I m in diameter.

The machine is equipped with a 2130 mm wide smooth vibratory drum which has a shell thickness of 50 mm for maximum productive lifetime.-TradeArabia News Service