The behavior of expanded polystyrene (EPS) geofoam used as subgrade and fil
l material under flexible pavement was investigated by carrying out a serie
s of tests in a model pavement testing facility. In the experimental setup,
pavement test sections that consisted of a wearing course, a gravel base l
ayer, and a sand subbase were placed on EPS blocks inside a test tank. Traf
fic loading on the test pavement was simulated using a loaded wheel running
on an oval-shaped test track. The investigation studied the effects of rep
eated traffic loading on the performance of the EPS geofoam, the influence
of the EPS block size, and the presence or lack of lateral restraint. For c
omparison purposes, a pavement section using sand fill instead of EPS geofo
am was also constructed and tested and is considered as the baseline case.
The performance of the EPS geofoam was benchmarked against the baseline cas
e to analyze its performance and to determine possible problems that may oc
cur when used in full-scale pavement sections. Implications for pavement de
sign are also discussed.