Strength Characterization of Stabilized A-5(10), A-7-5(16), A-4(3) and A-2-7(1) Laterite Soils Individually Using Supaset Cement

Abstract

The purpose of this research work is on the strength characterization of the Supaset Portland cement stabilized with laterite soil materials from four different borrow pits locations within Southwest part of Nigeria and the level of their usefulness for highway pavement subbase and basecourse. The four laterite soils after laboratory experiments are classified as A-5(10) silty soil; A-7-5(16) clayey soil; A-4(3) silty soil and A-2-7(1) clayey gravely sandy soil respectively. Stabilization of each laterite soil with the cement at percentages of 0% through 14% at the interval of 2% shows that with the increase in cement content during stabilization process the optimum moisture content of each soil specimen is reducing while the related maximum dry density is increasing. Furthermore, while considering at natural and stabilized states, both unsoaked and soaked California Bearing Ratio, uncured and unconfined compression strengths values of the tested specimens are increasing with increase in cement content with soil A-4(3) having the highest value while soil A-5(10), A-2-7(1) and A-7-5(16) values followed respectively. The coefficient of permeability of each soil specimen stabilized was reducing as the cement content was increasing. The chemical composition tests on Supaset Portland cement revealed CaO and SiO2 are the major components while for those of soils are SiO 2 and Al 2 O 3 . The significance of this study is that although A-5(10) and A-4(3) silty soils stabilized by Supaset Portland cement of grade 32.5R attained the 750 kN/m 2 minimum standard strength requirement for subbase, A-7-5(16) and A-2-7(1) clayey soils did not satisfy same. The justification for this research is that Supaset Portland cement is an economical and valuable material to stabilize silty soils but not cost-effective for the stabilization of clayey soils for highway pavement in order to prevent its incessant and premature failure.