Laboratory performance of geogrid and geotextile reinforced flexible pavements

Geotextile and geogrid reinforcement in flexible pavements were evaluated to determine potential benefits. Laboratory pavement sections were constructed, tested, and analyzed to assess the performance of reinforced pavement sections compared to sections without geosynthetic reinforcement. The pavement sections were designed to model a typical low-volume traffic secondary road built over a weak subgrade. The tests sections were constructed using different base course thicknesses and different subgrade CBR values. The pavements were dynamically loaded at a frequency of 0.5 Hz using a computer controlled pneumatic loading system. A force of approximately 9000 lbs (40 kN) was applied to the pavement through a rigid plate. This system modeled the dual tire load from an 18 kip (80 kN) truck axle. Surface deflections were measured during loading using an L VDT array. The performance of the pavement sections was assessed based on AASHTO and linear viscoelastic design procedures. A service-life-cost criterion was used to compare the performance of the test sections.