Airport Runway Makes Rapid Progress
The main focus of current works at the Airport site on the remote isalnd of St Helena is on the runway, taxiway and apron areas.
Progress continues, and at end-April 2015 the runway was nearly 70% complete with a total of 17,492 m³ of concrete already paved and 8,413 m³ still to be cast.
The Taxiway is almost complete with the exception of joint cutting and sealing and the Apron is 91% complete with 370 m³ of concrete still to be cast.
Kevin Pickard Projects has been sub-contracted by Basil Read to perform grooving and joint sealing of the concrete pavement works at St Helena Airport.
Grooving of the runway (excluding the two outer lanes, turning pads, Apron and Taxiway) is carried out using a GT1250 Grooving machine with forty-three 4 mm Arix diamond blades.
The purpose of the grooving is to prevent aqua planing which can be caused by water accumulation on the runway. The grooves, which enable the water to evenly drain off the runway, are in a pattern of 23 mm and 28 mm and are cut to a depth of 4 mm.
This grooving pattern prevents resonance when the aircraft lands on the runway.
Joint sealing is done on all concrete longitudinal and transverse joints which are cut to a width of 6 mm. The joints are then cleaned using high pressure water jetting and grit. Backing Core is installed at a depth of 17 mm and then joint sealant (Silicone 890 Dow Corning self-levelling sealant) is gunned into the joint. The purpose is to prevent water penetrating the sub-structure.