Estimation of Strength Development of Cement-Stabilized Clayey Soils with Activity Number, Liquid Limit, and Apparent Void Ratio

Abstract

Cement stabilization is a soil improvement technique widely adopted for soft soils. The extent of improvement to the physical properties varies largely with soil type and often requires laborious laboratory tests to ascertain such extent of improvement when soil samples from a source are obtained. To offer a quick estimate of the improved unconfined compressive strength of the composite, it is crucial to develop relationships of the strength with essential parameters of the soil. Furthermore, existing studies mainly focused on cement-stabilized clays with minimal granular content. The influence of commonly encountered sand impurities in actual field condition is much less discussed. In view of these limitations, the current study explores the use of activity number (A), liquid limit (wL) and modified apparent void ratio (ec*) as a proxy to unify the strength development of cement-stabilized soft soils used for land reclamation in the modified Abrams's strength predictive model. Incorporation of A and wL is achieved by introducing a new parameter α. Friction due to geometric proximity between sand particles in the composite is represented by ec*. Results show that the proposed model is able to successfully consider the effect of soil properties in the strength development of soils stabilized with Ordinary Portland cement (CEM I) and Portland blast-furnace cement (CEM III/C) and validated with published literature. The proposed models enable quick check of the design when only mix proportions and index properties are available. They also incorporate the influence of sand content, which is merely considered in existing models.