Engineering Characteristics of Chemically Treated Water-Repellent Kaolin

Abstract

Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO) ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase. The soil-water contact angle increases with an increase in CO until CO = 2.5%, and then maintains an almost constant value (≈134.0°). Resistance to water infiltration is improved by organosilane treatment under low hydrostatic pressure. However, water infiltration resistance under high hydrostatic pressure is reduced or exacerbated to the level of untreated clay. The maximum compacted dry weight density decreases with increasing CO. As the CO increases, the small strain shear modulus increases, whereas the effect of organosilane treatment on the constrained modulus is minimal. The results indicate that water-repellent kaolin clay possesses excellent engineering characteristics for a landfill cover material.

Characterization of Engineering Properties of Active Soils Stabilized With Nanomaterial for Sustainable Infrastructure Delivery

“…Ugwu et al (2013) discuss the reaction chemistry of Nanomaterial with the aim of facilitating a better understanding of the fundamental science that underpins the observed changes in soil geotechnical properties (i.e., hydrophobicity, plasticity, and swell potential). Choi et al (2016) investigated the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. Athulya et al (2017) Investigated effective utilization of steel slag, a by-product from the steel industry, as construction material in highway pavement layers so that the industrial wastes can be used and disposed properly with reduction in environmental impact as well as the FIGURE 1 | Active soil zone and layout of sampling i.…”

“…In order to study the magnitude of possible swell in the clay, the test suggested by Sivapullaiah et al (1996) was followed (Bailey, 1980;Sivapullaiah, 1996; ASTM Standard Test Methods for One-Dimensional Swell or Settlement Potential of Cohesive Soils, 1999;Das, 1999;Venkatramaiah, 2006;Maghsoudi and Dahooei, 2009;Okagbue, 2014;Choi et al, 2016;Syed et al, 2018). This appears to give a better indication for the swelling potential of clayey soil with a mass of about 10 g. The soil mass was well pulverized and transferred into a 100 ml graduated jar containing distilled water.…”

Valorisation and Modification of Saharan Clay for Removal of Cu(II), Ni(II), Co(II) and Cd(II) from Aqueous Solutions

“…Designed applications to improve environmental quality through heavy metal ions removal have recently emerged. Moreover, the versatility of the kaolin clay support to be chemically modified induces its application to produce new materials available for removing contaminates from water and soils [17][18][19][20][21][22].…”

Water-entry pressure in water repellent soils: a review

“…The importance of soil water repellency in geotechnical engineering has been recognized due to its significant effect on water infiltration, evaporation, soil strength, and soil stability [6,7]. Potential applications of water repellent soils (WRS) in ground infrastructure include hydraulic barriers for embankments, landfills, flood defences and other applications [8][9][10]. The assessment of water repellency hence becomes essential.…”