Bearing capacity of soft subgrade reinforced by geotextile

When geotextile is placed between a soft subgrade and aggregate layer, the bearing capacity of road system is significantly improved. In such application the basic function of geotextile are as follows: (1) confinement of subgrade soil and aggregate layer, (2) reinforcement by vertical compornent of tensile stress develops in geotextile, (3) material saparation. In this study, based on the results of two dimensional model tests, especially the first function is investigated.Geotextile reduces the stress transmission to subgrade and restrains the sliding failure of subgrade soil on both side of loading area. Next, the reinforcement of aggregate layer by geotextile is due to increasing of holizontal confinement stress, and it seems that this function has important effects upon the bearing capacity of road systems.