Swelling Pressure Prediction of Compacted Unsaturated Expansive Soils

Abstract

Generally, expansive soils undergoes significant volumetric deformation, which causes structural damages to existing infrastructures. Damages due to expansive activities are noticeable in pavements, buildings, earth dams, retaining walls etc. To estimate swelling stress, accurate assessment of soil absorption of water over time, with respect to soil volumetric change is required. However, the time frame requires for completion of swelling cycle is relatively long. With this in view, several attempts with great success have been made by researchers to predict swelling pressure of expansive soils using soil mechanics index properties. In this study, the interrelation between unsaturated soil mechanics property i.e. Matric suction () and geotechnical soil indexes were utilized to develop three predictive multi-regression equation for swelling stress. Series of Atterberg limit tests, matric suction tests, free swell index (FSI) tests and zero swelling tests (ZST) were performed to obtain the dependent and independent variables for the multi-regression analysis. Based on the experimental results, empirical relationships were developed to determine swelling stress as a function of matric suction, gravimetric moisture content (GMC), FSI, dry density and plasticity index using mathematical software package (NCSS11). The developed predictive multi-regression models were used to estimate the experimental swelling stress (. The scattered plot showed good agreement between the measured and predicted data, with coefficient of determination (R2) and mean square error (MSE) of 0.9443, 0.9793, 0.9310 and 0.0051%, 0.0021% and 0.0067% for models 1, 2 and 3 respectively.

Exploring the Influence of Plastic Powder Incorporation on Geotechnical Properties of Expansive Soil Stabilized with Granite Powder for Building Applications

“…However, when the percentage of powdered plastic increases, there is no effect on Wopt values because powdered plastic cannot absorb water (maximum 4% of its weight. Water can act as an intermediary agent between soil particles and reinforced material particles (plastic powder and granite powder) to reduce frictional resistance between particles in the mixture, thus improving compaction quality to achieve maximum dry density and the best possible soil properties after compaction [19,20] that water-saturated or dry clay soils make the compaction process difficult, leading to poorly compacted soils unless the compaction effort is adjusted.…”

Arcillas expansivas del Norte de Venezuela: Caracterización mediante el uso de los límites de Atterberg, índices de consistencia y ensayos de expansión

“…El potencial de expansión se puede determinar bien directamente en el laboratorio realizando pruebas de expansión-consolidación en un edómetro o bien predecir indirectamente a partir de las propiedades del suelo y valores de los índices de Atterberg tales como el índice de plasticidad, el contenido de arcilla, el índice de actividad (arcillas) y el índice de contracción, parámetros que sólo mantienen una relación indirecta con el grado de hinchazón (Zumraw, 2013). Basándose en datos experimentales, algunos investigadores han propuesto relaciones para el potencial de hinchazón que involucran tanto las condiciones originales del sedimento como sus propiedades índices (Seed et al, 1962;Rao et al, 2004).…”