Page 8 - GDL - EARTHWORKS GROUND IMPROVEMENT PILING

DEEP SOIL MIXING: MASS STABILISATION
Mass stabilisation is a versatile ground improvement technology which provides a fast and cost-effective method for the in-situ improvement of soft and saturated soils to depths of up to 5 metres.
The method with some adaptation of binders can also be utilised to solidify contaminated soils, and therefore in a single process you can remediate these from an environmental perspective as well as signi cantly improving their engineering characteristics.
The Process
Our process involves the injection of a wet cementitious grout under medium pressure whilst thoroughly mixing the soils using bespoke equipment designed in-house to create an entire block of improved material.
In addition to improving entire blocks of material, other layout arrangements are also feasible such as construction of wall panels and shallow columns.
Binders can include cement (OPC), y ash (PFA) and furnace slag (GGBS). The speci c requirements for each situation are determined through design and trials prior to commencement of the works.
The accuracy of the installation process is controlled through the use of instrumentation mounted on the excavator which records binder pressure and ow, and the GPS machine positioning system which guides the operator to undertake treatment to the required extents and depth.
Bene ts
• Cost Effective – stabilisation of unsuitable and / or contaminated soils to deem them suitable for site reuse avoids import / export costs
• Safe – the in-situ method avoids the requirement for signi cant deep excavations and the associated hazards
• Fast – can support advancing equipment and structures
within one day
• Sustainable – avoids the requirement to dispose of
unsuitable material and the importation of aggregate
• Adaptable – compact equipment with fast set-up time
allows the process to be utilised for a wide range of projects from the smallest up to multi-million pound schemes.
Applications
• Low permeability cut off walls
• In conjunction with other ground improvements
techniques, e.g. soil mixed columns
• Retaining wall foundations
• Vibration reduction / seismic strengthening
• Solidi cation of contaminants
• Foundations
• Road and rail embankments
• Slip repairs
• Utilities and drainage