| description abstract | A geofoam was produced by blending expanded polystyrene (EPS) beads and sands in proportions. The
formed mixtures, known as EPS-sands, were 26–63% lighter than general earth fills (e.g.,
sand). Consolidated-drained (CD) triaxial compression tests were conducted on EPS-sand mixture
specimens to observe their stress-strain characteristics, specifically, the stress-strain responses
in relation to the EPS contents (0.5, 1.5, and 2.5% by weight) used in the mixtures and confining
pressures (100, 200, 300 to 400 kPa) loaded on the specimens. The EPS content and confining pressure
were found to influence the stress-strain and volumetric strain behavior of the mixtures. Increasing
EPS content led to decreased shear strength and increased volumetric strain. Increasing confining
pressures enhanced the strength of the mixture. EPS-sand mixtures underwent a shear contraction
throughout the CD tests. The optimum EPS bead content (i.e., the one reasonably balancing the unit
weight, strength, and deformation) was in the order of 0.5% by weight. EPS content dependent strain
increment equations were derived by compromising Cam-clay and modified Cam-clay, and used to model
the stress-strain characteristics of EPS-sand mixtures. The established equations were verified
being able to depict the stress-strain observations of EPS-sand specimens, at least for the ranges
of EPS contents and confinements considered in this study. | |
