Use of geogrids from Tensar has played a key role in ground stabilisation for a major extension to Newcastle International Airport’s long term car park which is set to open this month.
Tensar worked closely with CK21 Consultants to develop an alternative pavement design to mitigate against differential movement while reducing overall pavement thickness to allow main contractor Owen Pugh Group to accelerate construction and meet the tight programme schedule.
Construction of the car park extension over former mine working will provide an additional 1,600 spaces. Work began in February and is expected to be finish later this month, in time for the start of the summer holiday season.
“The area of the new extension is underlain by historic mine workings, which have been treated,” said Tensar area civil manager Peter Matthias. “However, there was concern that differential settlement could occur in the transition zones between the treated areas and the weaker natural ground, over the life of the pavement.
“The two layers of Triax geogrid within the aggregate layer will create a flexurally stiff platform. When load is applied, the granular particles will partially penetrate through the geogrid’s apertures, confining and restraining them from moving both vertically and laterally, allowing variations in the underlying ground to be smoothed out.
“This stabilising effect allowed us to reduce the sub-base thickness, while maintaining its ability to carry the anticipated traffic loads and to mitigate against differential settlement.”