This video presentation of a site at Widnes (client, Halton Borough Council – HBG), where subsoil stabilisation works, to engineer soils (with an inherently low bearing capacity – average natural CBR value of untreated soils was in the region of 2%) for use as capping replacement materials, with a CBR value of 15%, and to solidify the soils.

Soils can also be treated for use as sub-base replacement materials, where the design matrix can produce a processed material which is non-susceptible to frost.

The opening scenes on the presentation show brief excerpts from various process stages – the cohesive candidate clays (with Plasticity Index ranging from 13% to 36%), the spreading of binders, soil mixing, compaction and trimming/grading to level.

The site formation to the car parks, to be treated, in this instance to a depth of 250mm, was prepared by the earthmoving contractor, either by excavation to reduce levels and/or by filling to make up levels, and was then compacted to seal the surface, prior to being made available for stabilisation.