Reuse of waste tire textile fibers as soil reinforcement

Abstract In recent decades, many geotechnical engineering researchers have used End of Life Tires (ELT) in different shapes for the purpose of soil reinforcement. One of the sub-products that are generated during the treatment of ELT are Waste Tire Textile Fibers (WTTF). These fibers are classified as special and hazardous wastes. Contrary to international laws, these wastes are burnt or buried, leading to several environmental problems. As an innovative research, reuse of the WTTF to reinforce soils is evaluated through design and performance of a set of laboratory tests. To that end, all mixtures are analyzed under compaction, direct shear, Unconfined Compressive Strength (UCS), California Bearing Ratio (CBR), and Split Tensile Strength (STS) tests after adding 0.5%, 1%, 2%, 3%, and 4% of WTTF on two types of clayey and sandy soils. WTTF are properly capable of improving all strength and ductility parameters of sandy soil. However in clayey soil, in spite of reduction in UCS and CBR, ductility and tensile strength are increased. As a result, instead of burying or burning these wastes, they may be well used for enhancing the mechanical properties of various types of soils. Different behavior of WTTF in clay and sandy soils are investigated by employing fundamental studies performed through optical microscope.