PHYSICAL AND MECHANICAL BEHAVIOR OF A CLAYEY SOIL STABILIZED WITH LIME AND SODIUM SILICATE FOR RURAL BUILDING PURPOSES

Abstract

Use of chemical stabilizers in earth aims at improving mechanical characteristics and behavior under water influence. The objective of this research was to study the effect of chemical additives (lime and sodium silicate) on mechanical properties of a clayey soil. The lime rates in the soil-lime mixtures were 0%, 6%, and 10%, and the sodium silicate rate was 4%. Soil was submitted to tests to determine its main physical indexes. Cylindrical specimens with 127 mm height and 100 mm diameter were molded. The specimens were cured in a humidity chamber for 7, 28, and 56 days. After each aging period, specimens were submitted to compressive tests. Water absorption capacity essays were carried out at the seventh day from molding. Only the 10% lime content associated with 4% sodium silicate reached the minimum strength required by soil-cement block standards. Regarding to total water absorption capacity, no treatment reached the values recommended by that standard. Results suggest a promising use of sodium silicate to improve strength and durability-related physical and mechanical characteristics of soil destined to rural buildings.

KEY-WORDS: Soil-lime; compressive strength; soil stabilization; earth building material.