Performance of Geotextile-Reinforced Bases for Paved Roads

Abstract

Geotextiles have been widely promoted for pavement structure, but only a few full-scale experiments have investigated the effects of geotextile reinforcement on pavement design. In this study, full-scale accelerated pavement testing (APT) was conducted on six pavement test sections with granular bases reinforced with various types of woven geotextiles. The control section had a granular base without any reinforcement. All sections were paved with Superpave® hot-mix asphalt (HMA). Base and subgrade materials were the same, but the test sections had varying thicknesses of base and asphalt layers. Each section was instrumented with two pressure cells at the top of the subgrade, six strain gauges on the geotextile, six H-bar strain gauges at the bottom of the asphalt layer, and two thermocouples. The sections were loaded to 250,000 to 400,000 repetitions of an 80-kN single-axle load of the APT machine. Mechanistic responses of the test sections were periodically monitored and analyzed. Rutting profile, pressure on the subgrade, strains in the geotextiles, and strains at the bottom of the HMA layer were measured. Falling weight deflectometer (FWD) tests were performed before and after loading. Reinforced-base sections with similar cross sections outperformed the control section in terms of rutting, and the reinforced-base layer reduced pressure on the subgrade. Backcalculated moduli from FWD tests demonstrated that the base layer in reinforced sections was significantly stronger than the control section base layer after loading. Strain measurements at the bottom of the HMA layer indicated that fatigue life of test sections did not improve with geotextile reinforcement.