Consolidated Undrained Monotonic Shearing Response of Hydrophobic Kızılırmak Sand

Authors : Kemal ÇETİN, Hüseyin Melih TATAR

Pages : 10675-10694

Doi:10.18400/tekderg.543306

View : 10 | Download : 2

Publication Date : 2021-03-01

Article Type : Research Paper

Abstract :Geotechnical properties of hydrophilic insert ignore into journalissuearticles values(wettable); sands have been widely discussed in the literature. However, sands may gain hydrophobic insert ignore into journalissuearticles values(non-wettable); properties after being exposed to a hydrophobic agent in the nature. The number of available studies regarding the response of hydrophobic sands is very limited, and mostly focus on their environmental and hydrological aspects. To close this gap, a controlled laboratory testing program, consisting of 18 monotonic strain-controlled consolidated undrained triaxial shear tests, was designed. Tests were performed on fully saturated hydrophilic and hydrophobic re-constituted Kızılırmak sand samples of different relative densities with pore water measurements. Hydrophobic samples were prepared by using 1 and 2 % WD-40 lubricant by mass. The effect of hydrophobic agent was assessed by comparing the stress – excess pore water pressure - strain responses of hydrophobic sand samples with those of conventional insert ignore into journalissuearticles values(hydrophilic); sand samples. Test results revealed that addition of hydrophobic agent increases the dilatancy of sands at low confining stresses insert ignore into journalissuearticles values(~100kPa); by decreasing the excess pore water pressure generation. At higher confining stresses insert ignore into journalissuearticles values(~400kPa); this effect is less pronounced. Moreover, the addition of hydrophobic agent up to 2% by mass does not systematically and significantly change the effective angle of shearing resistance of sand samples, independent of their initial relative density and confining stress levels.
Keywords : Kızılırmak sand, CU triaxial shear test, hydrophobicity, WD 40 lubricant, dilatancy, density, effective stress, critical state, stress strain response