INVESTIGATION OF VERTICAL SETTLEMENT DUE TO CONSOLIDATION ON SOFT SUBGRADES USING GEOTEXTILES

Abstract

One of the problems in road construction projects is the design and construction of roads on soft and weak subgrades. One of the methods to increase the bearing capacity of weak foundation soils is to reinforce those using synthetic fibers and polymers. Based on geotechnical studies and field tests conducted on the Urmia–Tabriz road by the Road and Transportation Organization of West Azerbaijan Province, the presence of an organic soil layer beneath the embankment was identified. In addition, the groundwater level in this area is high and is considered one of the causes of settlement. In this study, the effect of using geosynthetics to improve the properties of an embankment constructed on the soft subgrade of the Urmia–Tabriz road is investigated. Furthermore, the finite difference method using FLAC software and the Mohr–Coulomb model has been employed in analyzing the settlement of the embankment on the soft subgrade. The results obtained from the embankment analysis showed that reinforcing the model with geotextile leads to a significant reduction in vertical settlements. The performance of geotextile reinforcement in soil layers is both axial and frictional. The performance of the reinforcing layer varies across different soil layers. Overall, acceptable results were obtained.