You may have seen some of our construction staff rolling out what looks to be a carpet underneath new roads... Its not actually a carpet!
We are now using two new composite materials underneath newly resurfaced roads to increase strength and prolong their life, ultimately saving money. The result of using these products is stronger roads, with less movement and longer road lifespans. This is particularly useful where there is very reactive clay soil, such as suburbs east of Hampstead Road including Oakden, Hillcrest and Northgate.
The geotextile acts as a separation layer, preventing the clay underneath the road from mixing with the rock road base, thereby maintaining performance of the road base material. We then add a geogrid which acts as a stabiliser and strengthener for the road which limits movement.