A review of chemical stabilisation in road construction

This paper presents a literature review of the application of cement, lime and polymer emulsion in road construction. The focus is mainly on the soil candidates, binding mechanism, the reported strengths and weaknesses for each chemical stabiliser used in soil stabilisation. While it is generally agreed that cement is best suited for sand-sized to gravel-sized soil mixtures (well-graded), lime is mainly used for wet heavy-clay soil mixtures. Polymer emulsion is more suitable for silt-sized to fine gravel-sized soil mixtures (well-graded). Organic soils are the most difficult soil type to stabilise, and for any kind of chemical stabiliser used, the strength gain is relatively minimal. Cement undergoes hydration reaction which is rapid, and results in high compressive strength, while lime undergoes a slower pozzolanic reaction is slower, and provide lower compressive strength. Polymer emulsion depends on the rate of evaporation for the film formation to complete, and results in ductile polymer-soil matrix. Like lime, polymer does not provide significant compressive strength but does provide great flexural strength that prevents crack propagations. The outcomes from this paper provide an insight into recent and upcoming research trend using chemical soil stabilisers on local soil mixtures to improve the engineering properties of pavement layers made of these soil mixtures.