Axbridge Road
The project required the provision of a capping layer over weak ground, and the accommodation of construction traffic. It also had to provide a construction detail that would satisfy the requirements of the adopting authority, in this case Somerset County Council.
Benefits
- £86,000 (28%) estimated reduction in construction cost
- 1.5 days (37%) estimated reduction in construction time
- 6,320kg CO2e (38%) estimated reduction in environmental cost
A capping layer was required to reduce the thickness of aggregate whilst achieving a surface modulus of 50MPa (5% CBR) which is equivalent to a foundation class 1 in CD225. Somerset County Council had concerns regarding possible utility work in the future that would compromise any geogrids positioned within the carriageway. One of their key requirements was to allow only a single layer of geogrid.
The original design for the Tensar mechanically stabilised layer (MSL) contained 2 layers of grid to accommodate the poor ground. A re-design was carried out using Tensar InterAx, which required a single layer of geogrid and offered a reduction in overall thickness of the capping layer.
