Gammon Construction Limited (“Gammon”) has taken the lead in adopting new technologies in resolving the current labour shortage issue faced by the industry and to moderate labour intensity. The application of precast and prefabrication and photogrammetry for surveying are solutions sought after in reducing manpower, achieving safer and more sustainable construction.

 

Labour Shortage Data

 

According to Gammon’s internal survey on labour shortage conducted in August 2015, the percentage of extra workers required is at 8.14%. The shortage remains severe in key trades like concretor, formworker, bar bender and fixer, curtain wall installer, plasterer and plumber. The manpower forecast released by CIC in October 2014 also projected a lack of 10,000-15,000 skilled labour in the coming few years.   

 

Precast Pile Cap Shell

 

In order to save manpower and time, Gammon has extended its application of precast method for the marine viaduct elements at Tuen Mun-Chek Lap Kok Link – Southern Connection Viaduct Section project, such as the precast pile cap shells. The pile cap shell modules manufactured off-site are placed directly on top of the permanent piles and dewatered to support the construction of deep pile caps, without the need of cofferdams or marine falsework, hence the number of rebar fixers, welders, carpenters, riggers and divers could be reduced tremendously. The precast approach also reduces material wastages, working at height, and minimises the possibility if accidentally dropping concrete into the sea.

 

With the implementation of precast pile cap shells, total savings of 40,000 man-days are targeted, it also represents the crucial safety benefit, as less time will be needed for workers to be on site.

 

Photogrammetry

 

Gammon has also adopted the innovative surveying technology of photogrammetry. The use of drone and photogrammetry technology enables surveying to be done faster and with more details compared with traditional surveying. With this pioneering technology, the surveying job becomes less labour intensive and there is less demand on land surveyors to carry out tedious work. And the cost of traditional surveying work per square metre is HK$2, while the cost of photogrammetry per square metre is HK$0.1.