Dynamic properties of sand reinforced with non-woven geotextile sheets using resonant column and bender elements tests

This study examines an inclusion of non-woven polypropylene geotextiles sheets on dynamic properties of dry sand. Resonant column (RC), bender and extender elements (BE, EE) tests were conducted on sand reinforced with different numbers of geotextile sheets ($N_{gts}$) under varying confining pressures. The inclusion of geotextile sheets significantly increases not only the shear modulus ($G$) but also the damping ratio ($D$) of the reinforced sand specimen. As compared to the data reported in literature, although geotextiles with lesser tensile strength were being employed in the current research, the percentage increases in the values of G were, however, found to be relatively greater. The inclusion of geotextile also leads to a reduction in the amplitude of the shear strain ($\gamma$). The values of shear and Young's moduli ($G_0,E_0$) determined respectively from BE and EE tests also confirm the improvement in moduli values for sand reinforced with geotextile sheets. The improvement in Young's modulus is found to be, however, relatively smaller. The effect of an inclusion of geotextile sheets on (i) percentage increase in $G_0$ and percentage decrease in ${\gamma }_{\min }$ increases continuously with an increase in ${\sigma }_3$, and (iii) percentage increase in $D_{\min }$, however, reduces with an increase in ${\sigma }_3$.