ELECTROKINETIC STABILISATION OF SLOPES A revolutionary
Transcription
ELECTROKINETIC STABILISATION OF SLOPES A revolutionary
ELECTROKINETIC STABILISATION OF SLOPES A revolutionary alternative treatment for failing slopes Features: The treatment, developed and patented by Electrokinetic Ltd, is based on the electro-osmotic flow of groundwater between electrodes when subjected to a voltage gradient. It has four main components: 1. Reduction in pore water pressure and subsequent consolidation of soft materials; 2. Reinforcement - EKG anodes act as soil nails with the advantage of an electrokinetic bond; 3. Horizontal drainage, both during active EKG treatment and long term passive drainage, post treatment, via cathode installation; 4. Physico-chemical changes in the soil, enhanced by the optional use of conditioning fluids. quickly from hydraulic hammer to drill auger, allowing both anodes and cathodes to be installed at any angle into the ground. Once installed, the electrodes are connected to a DC power circuit and electrified for a number of weeks. When electrification is complete, the cables and power supply are removed. The tips of the anodes are cut away, grouted in, and then capped off with a galvanized face plate. This acts as a soil nail, aiding stability of the slope. Both anodes and cathodes are left in place to provide long term reinforcement - the anodes - and passive drainage via the cathodes. The electrodes are made from modern woven materials, known as electrokinetic geosynthetics which have been specifically developed for this purpose. Method: Anodes and cathodes are inserted at angles into the failing slope in accordance with a site-specific customdesigned grid layout. The anodes are driven into the slope by hydraulic hammer, whilst the cathodes are inserted into preaugured holes. Given that slopes are also unstable, uneven, and often alongside busy carriage ways or railways with restricted or limited access, conventional drilling rig systems cannot meet these exacting installation demands. However, our unique P45K rig can easily, quickly and safely install electrodes on slopes of up to 50° gradient. The rig is track mounted with a winch cable for additional anchorage. The unique side mounted mast has been designed to enable the rig to switch Electro-osmotic induced flow of water inducing cementation around the anode and water dissipation via the cathode For further details please contact: Chris Morgan chris.morgan@geoeng.co.uk Or visit our website www.geoeng.co.uk Ds005 v01 Geotechnical Engineering Limited, Centurion House, Olympus Park, Quedgeley, Gloucester. GL2 4NF Tel: 01452 527743 Applications: · Unstable railway embankments across the UK, owing to their age and method of construction, are ideal candidates for this treatment. EKS is cost effective, safe and significantly minimises disruption to passenger and freight services. · EKG slope remediation can be applied in slopes with heterogeneous and homogeneous soils, dominated by fine grained materials, which have failed owing to a combination of steep slopes, weak soils and poor drainage. · Failing road embankments, which may be hard to access can be successfully treated and the system has the added value of providing low impact to ecologically sensitive sites. chemical changes in the soil, such as cementation, flocculation & precipitation. To learn more about the practical application of this technique, read our case study: EKS on the A21 in Kent. Benefits: Cheaper: Cost savings of 26-38% have been estimated on projects completed to date. Safer & Quicker: Lane closures are not required. Special access requirements are minimal and fewer staff are needed on site. Existing slopes are treated in situ, removing the need for disruptive major works which are normally associated with traditional methods. Reduced carbon footprint: 40-60% reduction compared to soil nailing or slope slackening and 75% compared to granular replacement. P45k rig inserting anodes at an angle of 20°on a slope beside a highway Preserves habitats: Trees and top soil remain in place, thereby preserving root balls, seed banks and conserving protected species. Sustainable: Drains and converts banks into stable structures with increased shear strength and stiffness by electro-osmotic de-watering and physico- For further details please contact: Chris Morgan chris.morgan@geoeng.co.uk Or visit our website www.geoeng.co.uk Ds005 v01 Geotechnical Engineering Limited, Centurion House, Olympus Park, Quedgeley, Gloucester. GL2 4NF Tel: 01452 527743