Additional site trials are being carried out concurrently with consultation on a new guidance document for rock netting in order to maximise the benefits to industry.
Ciria’s new rock netting document is due to be published in summer 2016 and is expected to include data from site trials currently being undertaken in Derbyshire.
Speaking at GE Slope Engineering and Geotechnical Asset Management conference in London today, Aecom associate Adrian Koe revealed details of work that could cut the cost of delivery on some rock net solutions. Aecom is working with the University of Leeds and Can Geotechnical to develop the new guidance.
“During the work to develop the guide, it became clear that draped net solutions introduce interface friction and there is a high proportion of load transfer at the crest,” said Koe. “We believe that there is a potential to save on the number of anchors required at the crest.”
Koe was reluctant to put a number to the potential savings but said that less than 10% of the load is placed through the top anchors.
“We are undertaking research alongside the new guidance to look at the issue and we are working with Dywidag, Maccaferri and Geobrugg,” he said.
“We installed two types of netting on two slopes with differing morphology at a discussed quarry on the Chatsworth Estate in Derbyshire several weeks ago. We have just carried out some load testing and have more planned for January.
“We hope to be able to include the result within the new guidance as well as publishing the findings separately.”
The guidance is aimed as a new UK guide but has already attracted international interest and will include sections on design, installation and asset management.