Experimental characterisation of clay-sand mixtures treated with lime

Abstract

Lime stabilisation is a process which chemically improves numerous characteristics of the soils, among which aspects, the mechanical properties increase are the most noticeable. This paper investigates the lime treatment of mixtures of sand and bentonite at different proportions. Three physical characteristics are measured at different curing times: the mechanical strength is deduced from unconfined compressive strength (UCS); the chemical reaction is evaluated based on the lime consumption (LC) and the electrical properties are obtained from electrical resistivity (ER). Results show that all three physical characteristics increase with curing time and that the optimal UCS appears at mixtures with low bentonite content (i.e. 10–15% bentonite). LC curves show that the kinetics of the lime reaction is also slower at these low bentonite contents. Finally, the ER curves show similar patterns for all mixtures and are closely related to the LC.

Keywords:

• unconfined compressive strength
• electrical resistivity
• lime treatment
• clay–sand mixtures

Acknowledgements

We are grateful to Mr. Nicolas Canu, from BATir department, and Mrs Tiriana Segato, from 4MAT department of ULB, for their provision of technical support.

Notes

No potential conflict of interest was reported by the authors.