Creep and stress relaxation phenomena occur simultaneously in a geosyn
thetic-reinforced soil (GRS) structure. Therefore, the simultaneous me
asurement of creep and stress relaxation occurring in a soil-geosynthe
tic composite during long-term laboratory interaction tests is essenti
al. This paper describes a new test apparatus that measures creep and
stress relaxation simultaneously in soil-geotextile composites, which
is essential for understanding the long-term interactive behavior betw
een geosynthetic reinforcement layers and the confining soil.