The impact of alccofine inclusion on the engineering properties of bentonite

Abstract

This paper assesses the engineering properties of bentonite-alccofine mixtures through a series of compaction, consistency limits, and unconfined compressive strength tests along with the SEM-EDX analysis. The alccofine content in the mixtures were 0%, 2%, 4%, 6%, 8%, and 10% by the dry weight of the specimens. Compaction test results reveal an increase in the dry unit weight and a decrease in the optimum moisture content up to 8% inclusion of alccofine. With the increase in alccofine content, the consistency limits of the mixes decrease. Furthermore, the maximum values of unconfined compressive strength, secant modulus, peak strain energy, deformability index, shear modulus, and resilient modulus of 28 days cured specimens of bentonite-alccofine mixtures prepared at ω opt - 3%, ω opt, and ω opt + 3% are observed for specimens with 6%, 8% and 8% alccofine content, respectively. The results of the morphological study reveal an increase in the Ca/Si ratio and a decrease in the Si/Al ratio up to an alccofine content of 8% in the bentonite. However, the Si/Al ratio increases beyond an alccofine content of 8%. Based upon the test results and comparison with various Indian standards, the quantity of alccofine to be added in bentonite should be in a range of 6%–10%, for its application in the construction of embankments, base, and subbase courses of rural roads.