Laboratory Evaluation of the Performance of Geosynthetic-Reinforced Aggregate over Weak Subgrade

摘要

The objective of this study was to evaluate the performance of geosynthetic-reinforced aggregate bases for unpavedrnroads over soft subgrade using laboratory plate load test. The model tests were conducted in a 1.5 m long, 0.91 mrnwide, and 0.91 m deep steel test box. The load was applied through a 190.5-mm diameter steel plate. Thernparameters evaluated in this study included the thickness of aggregate base surfacing, the location and tensilernmodulus of geosynthetics, and the number of geosynthetic reinforcement layers. Test results indicated that therngeosynthetic reinforcement resulted in appreciable reduction of surface deformation and increase of bearing capacityrnfor unpaved aggregate base over soft subgrade. The test results also showed obvious effects of the geogridrnarrangement/location on the unpaved test section’s performance, with the double reinforcement location consistentlyrnyielding the largest improvement. Higher tensile modulus geosynthetics performed better than others. Greaterrnimprovement due to geosynthetic reinforcement was seen for test sections with thinner aggregate base surfacing.