ABSTRACT
Expansive subgrade soils rich in montmorillonite clay are highly prone to swelling due to moisture fluctuations, leading to heave and reduced riding comfort. Pavement edges with inferior aggregates allow higher water infiltration, causing differential heave. To investigate this behavior, laboratory-scale model tests were conducted in a 1.5 m × 1.5 m × 1.5 m chamber using a pavement system comprising a 50 mm existing subgrade, 500 mm prepared subgrade, and 400 mm Wet Mix Macadam (WMM) layer. A 250 mm diameter plate applied uplift force equivalent to a swell pressure of 450 kPa to simulate moderate to high differential heave. Geocell reinforcements with cell depths of 100 mm, 150 mm, and 200 mm were introduced to evaluate their effectiveness in mitigating heave. The results showed subgrade heave reductions of 54%, 57%, and 66%, respectively. Stress distribution analysis further confirmed their effectiveness in improving pavement stability and mitigating swell-induced damage.
