Ground engineering contractors

Vibro compaction is a ground improvement technique that densifies clean, cohesionless granular soils with a downhole vibrator. It’s a technique first developed by Keller in the 1930s and has been used on thousands of projects since: reduce foundation settlement; increase bearing capacity, allowing reduction in foundation size or width; increasing

Jet grouting uses high velocity fluid jets to construct cemented soil of varying geometries in the ground. It is often the preferred solution in any situation requiring control of groundwater or excavation of unstable soil (water-bearing or otherwise), and can be used to underpin foundations such as quay walls and heavy structures, as well as provide excavation support

Rigid inclusions is a ground improvement method using high deformation modulus columns constructed through compressible soils to reduce settlement and increase bearing capacity. Ground improvement efficiency depends on the stiffness relationship between the soil and the columns. Load from the structure is distributed to the soil and columns via a

Wet soil mixing, also known as the deep mixing method, improves the characteristics of weak soils by mechanically mixing them with cementitious binder slurry: road and railway embankments; support of strip, pad and slab foundations when traditional piling methods cannot be used; bridge supports and abutments, wind-turbine foundations; retention

This technique involves the improvement of weak soils by the installation of densely compacted columns made from gravel or similar material with a vibrator. The displacement process reinforces all soils in the treatment zone and densifies surrounding granular soils. This technique was first developed by company founder, Johann Keller, and has been

Permeation grouting, also known as cement grouting or pressure grouting, fills cracks or voids in soil and rock and permeates coarse, granular soils with flowable particulate grouts to create a cemented mass

Keller offers a complete design and construct service using rotary and rotary percussive drilling methods to install both hollow and solid bar soil nails. We maintain a variety of plant so that they can deal with the challenges of site conditions and productivity targets. With available development land becoming ever more costly, gaining usable

Compaction grouting involves the injection of a low slump, mortar grout to densify loose, granular soils and stabilise subsurface voids or sinkholes. It is suitable for rubble fills, poorly placed fills, loosened or collapsible soils, soluble rocks and liquefiable soils

Compensation or fracture grouting is the injection of a cement slurry grout into the soil creating and filling fractures that then lift the overlying soil and structures. Applications include re-levelling structures, and stabilising and mitigating the settlement of overlying structures during tunnelling

Rock grouting is normally done in fissured rock to reduce the flow of water along the joints and discontinuities in the rock. Applications include: reducing conductivity/transmissivity via interconnected porous zones in an aquifier; increasing resistance against deformation

Mixed modulus columns, also known as columns with Mixed Moduli, mixed columns or CMM®, is a sustainable ground improvement method using high deformation modulus columns constructed through compressible soils to reduce settlement and increase bearing capacity. CMM® is the combination of a rigid inclusion for its lower part with a ‘supple’ inclusion

Dynamic compaction involves the controlled impact of a crane hoisted weight, of around 10-12 tonnes, falling in a pre-determined grid pattern to improve loose, granular and mixed soils and fills: increase bearing capacity; decrease settlement; mitigate liquefaction; avoid major below-ground obstruction removal. Dynamic compaction is a ground

This technique involves construction of concrete columns with a bottom-feed depth vibrator to transfer loads through weak strata to a firm underlying stratum: as an alternative to piling techniques which generate spoil; avoid piling into deep aquifers; supporting road and rail embankments when other vibro or soil mixing techniques cannot; when a

Keller devised a foundations solution for a Nuclear Advanced Manufacturing Research Centre site which could not be treated by vibro. Using rigid inclusions avoided the need for piling, reducing the project's carbon impact. The construction of a 46,700 sq ft Nuclear Advanced Manufacturing Research Centre (NAMRC) facility within the Infinity Park

Keller was contracted to help stabilise and reinforce the sea defence and ground in front of a council car park in Lyme Regis that had been affected by years of corrosion. Typical anchors would not generate the load required, so Keller elected to use its SBMA anchors which allow multiple anchors to be installed in the same bore. Access to drill the bores was hampered by

Keller provided a cost and carbon saving option in challenging site conditions for the regeneration of a large brownfield site in the Black Country. Close collaboration with remedial, mining, geotechnical and structural consultants demonstrated the value of early involvement in the scheme. The Bilston Urban Village site has a long history of

As part of the regeneration of the former Jaguar car plant site in Coventry, a 105,699 sq ft bespoke food manufacturing and distribution facility was built for a major UK logistics provider. The new facility was constructed over a brownfield site with a highly variable thickness of reworked fill material, which contained pockets of buried topsoil

Replacement buildings were needed for a 750-place secondary school after the original buildings had come to the end of their lifecycle. Keller's scheme resulted in a significant carbon saving over a CFA solution. The new school comprised a two and three-storey main teaching block. The main challenge was to provide a solution through variable

The development of a new unit at Logic Park Industrial Park, Leeds, required regrading of part of the sloping site and steepening of the slope to the North of the unit. During the main works Keller installed soil nails to the face of the slope cut by others in a top to down sequence and Phi Group installed gabion cladding

Keller provided a low vibration fully displacement solution for a new single-storey fast food restaurant on a site where there was a danger of forming a pathway to contaminate an aquifer below the surface. The solution also delivered a lower carbon alternative to driven piling. The main challenge was to provide a solution through the very

Working closely with Curtins Consulting, Keller delivered a low carbon foundations solution in line with the UK government’s energy consumption and net zero targets. Works were completed in less than four weeks. The-place academy is being constructed to replace the existing 50+ year old facility. The new school comprises a three-storey teaching

Keller was contracted by Willmott Dixon Construction Ltd to install rigid inclusions on its project at the Maritime Training Hub in Whitby. Keller was able to provide a solution that enabled the use of shallow simply reinforced footings and was also low vibration as work was taking place near existing services and retaining structures. The soils

A tricky problem of constructing a 27,000 sq ft warehouse on the site of an existing office block development, next to live services and a sewer was dealt with using with a combined low-vibration Rigid Inclusions and King Post Wall solution from Keller, which was approved by Thames Water. The main challenge was to provide a foundation and

Keller carried out innovative foundation solutions to assist with the construction of the new 3-storey, 60-bed Galleyford Care Home in Chelmsford. These included: facilitating shallow simply reinforced spread footings; utilising a smaller low headroom rig to minimise temporary work requirements; offering a low vibration methodology in a residential area