Assessment of strength and matric suction of an artificially cemented silty soil under 500 days of cure

ABSTRACT

This article evaluates the development of resistance of simple compression (q_u) and matrix suction (Ψ) of an artificially cemented sedimentary soil over 500 days, curing time few studied in the literature. Simple compression was systematically investigated over 500 days and the matric suction parameters were investigated over 180 days. For this, a silty soil from the Guabirotuba Formation in Curitiba/PR was stabilized with hydrated lime with percentages of 3, 5, 7 and 9% in reference to the dry mass of the soil at curing times of 15, 30, 60, 90, 180, 360 and 500 days unconfined compression and for 15, 30, 60, 90 and 180 for matrix suction. Samples were molded with different lime contents (L), different porosities (η), different apparent dry specific weights (γ_d), different molding humidity (ω) and subjected to unconfined compression and matrix suction tests using the filter paper technique at different curing times. The porosity/volumetric lime content (η/L_iv) ratio was used to evaluate the development of q_u. The results demonstrate an increase in resistance with the increase of the curing time, with the increase of the lime content and with the decrease of the voids (that is, greater dry specific weight). Finally, a dosage equation for of the studied soil and mixed with lime was created with the ratio η/L_iv adjusted to an exponent 0.18. Finally, it was found that 64% of the compacted mixtures of lime with soil reach the minimum requirements for potential use in sub-base for q_u ≥ 1200 κPa, according to current standards.

Keywords
Lime-soil; unconfined compressive strength; porosity/lime index; dosage equations; suction