Systems from Tensar International, a worldwide leader in the manufacture and the provision of subgrade stabilisation, pavement optimisation and soil reinforcement, have been selected for use in the construction of a flood defence system in the Somerset village of Muchelney.
Frequently falling victim to flooding, Muchelney's roads were earmarked for Central Government funding following flood events in 2013, with new designs seeing the village's Law Lane being raised by 1.2m to allow continued access.
Tensar products were specified by the defences' designer, Atkins, and approximately 25,000m² of Tensar TriAx® geogrids and 15,000m² of Tensar uniaxial geogrids were used to support the redesigned road. Both Atkins and Tensar worked closely with main contractor Skanska and Somerset County Council throughout the works.
Providing near isotropic 360° radial load spread properties, TriAx geogrids provided reliable, initial stabilisation over the site's extremely soft ground, which includes areas of peat.
As increasing the road's height will create a substantial embankment imposing significant loads onto the weak foundation, further layers of TriAx® geogrids have also been included in the designs to help mitigate differential settlement of the road structure, while uniaxial geogrids will provide lateral restraint to prevent the sides of the embankment from slipping.
Commenting on the work being undertaken, Geoff Carter, Area Civil Engineer at Tensar International, said: "It's an honour to be involved in such a vital project. By creating a causeway in the event of flooding, the new raised road will create a much needed access route into and out of the village.
"The use of our geogrids will assist in the rapid construction of the road, allowing the side slopes to be kept as steep as possible. The minimal footprint of the new road embankment keeps additional land-take to a minimum in order to reduce the site's impact on the surrounding area."
Roger Ingram, Project Manager at Skanska added: "As the highways maintenance contractor for Somerset County Council we're well aware of the devastating impact that flooding has on the area. By raising Law Lane we can provide residents with a much needed lifeline in even the most severe conditions."
The project is due for completion later this year.
