Performance Evaluation of Scrap Rubber-Sand Mixture Reinforced with Geogrids as a Backfill Material in Retaining Walls

Abstract

Recycled waste tire rubber has many applications in construction field like the mixture of scrap rubber with sand can be effectively used as an alternative for reinforced backfill material in retaining structures which is common in transportation projects. However, studies on interaction properties between rubber-sand mixture and geosynthetics are needed for an effective backfill designing. Hence, this study is mainly focused on the influence of rubber content and rubber sizes on strength characteristics of the rubber-sand mixture and also estimates the interface shear strength properties of rubber-sand mixture with geogrid reinforcement when this material is used in mechanically stabilized retaining walls. Large-scale direct shear tests on rubber-sand mixture for various rubber contents varied from 10 to 50% by volume were conducted, and maximum peak strength was obtained for a rubber content of 30%. Hence, there is a significant increase in shear strength as the size of rubber is increased. Responses from interface shear strength between rubber-sand mixture and geogrid showed that there is no significant difference in the interfacial frictional strength when rubber-sand mixture is reinforced with geogrids. The findings lead to a sustainable as well as cost-effective design of retaining structures.KeywordsRubberShear stressInterfacial shear parameters