Characterization of Problematic Expansive Soils from Mineralogical and Swell Characterization Studies

Abstract

Expansive soils are those that expand when hydrated, and shrink when they were drying. These soil movements cause extensive damage to buildings, roads, pipelines, and other structures and the repair costs are estimated to be billion dollars annually. Expansive soils cover across most of the continents in the world, including several regions in the Saudi Arabia. For example, the regions including Tabuk, Al-Hafuf, Al-Qatif and Al-Ghatt have expansive soils and several infrastructure problems were reported in these regions. A research study was conducted at the King Saud University to characterize the severity of problem natures of these soils. Soil samples from these regions were collected and cataloged and these soils were subjected to a multitude of geotechnical related swell and shrink characterization studies. Three dimensional swell and linear shrinkage bar tests were conducted on these soil samples at targeted moisture contents to measure their volume change potentials. Severity nature of these expansive soils is then characterized based on an established swell/shrinkage ranking method practiced in the expansive soils literature. This paper presents a summary of these results and ranking assessments on the four expansive soils.