Optimizing CBR of Expansive Soil Subgrades Using Woven Geotextiles for Road Construction
Authors- Rammohan Sharma, Hariram Sahu
Abstract-This study investigates the effect of geotextile reinforcement on the stabilization of expansive soils used in pavement subgrade applications. Expansive soils, prone to swelling and shrinkage due to moisture fluctuations, present significant challenges for road construction. Laboratory experiments, including California Bearing Ratio (CBR) tests under soaked and unsoaked conditions, were conducted to evaluate the performance of two woven geotextiles (PEC-50 and HP-370) placed at varying depths (4 cm, 7 cm, and 8 cm) within the soil samples. The results demonstrate that geotextile reinforcement significantly improves the load-bearing capacity of expansive soils, with the highest CBR value of 4.32% achieved using PEC-50 at a 4 cm depth. Geotextile placement closer to the upper layers of the soil provided superior performance due to better load distribution and resistance to deformation. PEC-50 consistently outperformed HP-370 across all placement depths, highlighting the importance of geotextile material selection. The study concludes that geotextile reinforcement is an effective solution for stabilizing expansive soils, particularly in moisture-sensitive regions. Practical recommendations include optimal placement depths, geotextile selection criteria, and considerations for multi-layer systems in high-load scenarios. Future work should focus on field validation, dynamic loading effects, and the environmental impact of geotextile applications. This research provides a foundation for cost-effective and sustainable pavement design in expansive soil regions.