A time and labour saving method of geotechnical engineering for erosion control, soil retention and slope reinforcement. The Terra-lock system uses anchors that can now achieve up to 32.5kN’
Bardon Hill Quarry, Coalville, England
Terra Lock, Gripple Petrol Driver, JackJaw
- Client: Aggregate Industries
- Contractor: Dawnus
- Consultant: HBPW
- Application: Clay slope reinforcement and protection
Bardon Hill Quarry is a 58.2 hectare geological Site of Special Scientific Interest near Coalville, Leicestershire. The quarry has been operational for over 400 years, and produces three million tonnes of rock a year - 15% of UK output. The client, Aggregate Industries, needed to extend the quarry and move the on-site conveyor belt system, meaning around 150m of firm clay slope needed reinforcing. Initially, the client had looked at installing a gabion system for this purpose, but the supply cost and projected time of installation meant that alternative methods of reinforcement were required.
Gripple were asked by the main contractor, Dawnus, to propose an alternative solution to the cost and labour intensive traditional methods. A Gripple engineer visited the site to carry out an initial survey and provide design recommendations for the 150m of firm clay, based on core engineering principles and soil conditions. Several slope stability calculations were carried out for the varying slope profiles, to ensure the correct and most cost-effective system, depth and spacing was selected to meet the requirements of the project.
After consultation, Gripple’s TL-606 TL-A4, GMAT-T50 and TL-P2 were proposed to retain the slopes. Terra-Lock™ is an innovative method of geotechnical engineering for heavy erosion and slope stability, which creates sustainable and durable green structures by reinforcing nature. The GMAT-T50 is an erosion control mat backed with a high tensile strength geogrid, which acts as a solid barrier to earth movement and allows the anchors to work together. The TL-606 TL-A4 ground anchors are driven deep beyond failure planes to arrest slip planes, preventing earth movement and failures. Gripple engineers were able to deliver a minimum saving to Dawnus of 1210* tonnes of import rock (delivered in 60 trucks) which would have been required to fill the gabions on a traditional system install. The installation was also around 1/5th quicker than a traditional method.
Once installed, the GMAT was hydra-seeded and top soiled - perforations in both the TL606 and TL100 top plate are designed to facilitate vegetation regrowth, delivering a system that blends in well with the natural environment. Throughout the project, Gripple provided ongoing technical onsite support, as well as a post-project delivery service that included pull-out testing, training and sign-off.
Why use Gripple?
- Significant time and cost savings on your project
- Considerable reductions in packaging, vehicle movements & embodied CO2
- A range of support services at every stage of your project, provided by our technical team