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