Improved performance of calcareous sand subgrade reinforced by soilbags under traffic load

The performance of a subgrade composed of layered soilbags fabricated from polypropylene (PP) woven geotextiles filled with calcareous sands was investigated. Dynamic load tests were performed in an indoor model groove. The vibration acceleration, soil pressure and vertical deformation were analysed, and a vibration attenuation coefficient and deformation reduction ratio were developed. The results showed that the common quartz sand subgrade was softer than the calcareous sand subgrade subjected to traffic loads. The calcareous sand filling subgrade showed different acceleration attenuation features and the soilbag reinforcement reduced the cumulative deformation. Through the combined effects of a woven PP bag and expandable polyethylene foam, the subgrade reinforced with soilbags made from the composite material showed the best performance.