Shear strength characteristics of two-layer geotextile reinforced with flowable fill

Abstract

Geosynthetics have been applied in various engineering fields. This study investigates the shear strength of a two-layer geotextile reinforced with a flowable fill. Three types of geotextiles and a flowable fill are used to compare the shear strength characteristics. Direct shear tests on both unreinforced and reinforced geotextiles are performed on three geotextiles under three normal stresses for five curing periods. The experimental results show that the peak and residual shear strengths of the reinforced geotextiles are larger than those of the unreinforced geotextiles. A reinforced geotextile with a higher warp/weft density and crossing-over firmness factor shows significantly higher peak shear strength than the other two geotextiles. The peak and residual strength gains of the reinforced geotextiles depend on the geotextile type and curing period. The peak friction angles of the unreinforced and reinforced geotextiles cured for 28 days are influenced by the weave structure parameters. The two-layer geotextiles reinforced with flowable fill proposed in this study can be adequately used with a better understanding of their shear strength characteristics and influencing factors.