Six Dynapac compactors take off for Laos airport upgrade

The airport, one of the three international airports in the land-locked country, is being upgraded under a 320 million baht (US$9.14 million) soft loan from Thailand.

Italian-Thai, the largest infrastructure construction company in Thailand, and which is carrying out the works under a 234 million baht contract, took delivery of the compactors from Dynapac’s sole distributor in Thailand, the MEC Group.

The renovation will raise the airport’s capacity to support Boeing 737 and Airbus A320 aircraft, which will help promote tourism to Champassak, the southernmost province of Laos.

Upgrading works will expand the runway from its present length of 1,825 m to 2,500 m. The width of the runway is being increased from 36.6 m, having 4.2 m added to one side and 3 m to the other, taking it to a total width of 43.8 m. The runway is being paved with asphaltic concrete. A five-storey air control building is also being constructed.

MEC’s President for Dynapac, Anuwat Burapachaisri, says that there are four units being used for compaction of the runway sub-base, base course and wearing course. These are two CA252D single-drum medium-range vibratory soil compactors, and two CP210 pneumatic-tyred rollers, fitted with five steered oscillating front wheels and four traction rear wheels.

The new runway structure is between 1 and 2.5 m deep. Mr Anuwat says that two layers of sub-grade were laid, both of them 20 cm thick, forming a total 40 cm thickness. The first layer was compacted by equipping the CA252D with a padfoot drum and performing four passes over the soil. The padfoot drum was then replaced with a smooth drum and the compactor performed four more passes, giving a total compaction of 95 percent. The second layer of sub-grade was then added, and the process repeated.
 
Two layers of sub-base were then laid, both of them 15 cm thick, forming a total sub-base of 30 cm. The padfoot drum was passed four times over the first layer, followed by five passes with the smooth drum, to give a total compaction of 98 percent. The second layer was then added, and the same number of passes performed with the two drum types.

Two layers of base course were next added, both layers being 15 cm thick, forming a total base course of 30 cm. The smooth drum was used on both of these courses, with between 10 and 12 passes performed to give a compaction of 100 percent. 
 
Three layers of wearing course are being laid, each of them 5 cm in thickness, giving a total wearing course thickness of 15 cm.  The two CP210 pneumatic-tyred rollers are then being used for 17 or 18 passes across each of the wearing courses to give a total compaction of 98 percent.
 
Mr Anuwat says the final asphalt surfacing of the runway will be carried out by two CC222HF double-drum asphalt compactors, machines that weigh 7,700 kg and have a drum width of 1450 mm. These are articulated tandem rollers that feature pivotal steering on the rear drum, giving up to 500 mm offset.

“MEC is very pleased indeed to be involved in this project, which will help the Lao tourism industry to develop,” he adds. “We have supplied Dynapac vibratory compactors to other significant development projects in the country, and have a long experience of working in Laos.

“Because Laos and Thailand share a common border, we are able to supply all maintenance needs for the machines directly from our office in Bangkok.”
 
Although tourism arrivals to southern Laos have until now been modest, there is considerable growth potential once the airport has been upgraded.

According to statistics from the Lao National Tourism Administration, during the period 2006-2007 about 160,000 tourists visited Champassak province. This figure marked a rise of 45 percent over the previous period. One of the major attractions in the province is the Khmer-era stone-built temple of Vat Phou, believed to be older than Cambodia’s Angkor Wat. Vat Phou Temple has recently been declared as UNESCO’s second World Heritage Site in Laos.