Characteristics of Geotextile-Encased Soil Subjected to Cyclic Liquefaction Loads

Abstract A series of cyclic and postcyclic triaxial tests was conducted on geotextile-encased soil specimens to investigate the influence of fabric encasement on soil behavior under principal axis loading. Results indicate that the encasement of geotextile fabric is mobilized more efficiently in denser soil matrices. Theoretical tension force efficiency within the fabric was found to depend on both soil density and the magnitude of applied load. In all encased specimens, cycles to material softening were generally higher than for unencased soils, with encased specimens resisting approximately 1.7–22 times more cycles depending on fabric type and density. Additionally, when shear modulus per cycle was plotted against strain, loose encased specimens exhibited increased stiffness values within the strain range of 0.001% to 1%, while the opposite trend was observed for denser specimens. An onset of particle reengagement was first achieved in looser specimens at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="tilde 0.2 percent sign" display="inline" overflow="scroll"> <mml:mo form="prefix">∼</mml:mo> <mml:mn>0.2</mml:mn> <mml:mtext>%</mml:mtext> </mml:math> axial strains compared to denser ones at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="tilde 0.5 percent sign" display="inline" overflow="scroll"> <mml:mo form="prefix">∼</mml:mo> <mml:mn>0.5</mml:mn> <mml:mtext>%</mml:mtext> </mml:math> , which later contributed to improved matrix integrity. A theoretical energy-based analysis was introduced as a framework to analyze the behavior of the soil and encasing fabric.