Project engineer, TEAM Services, Des Moines, IA
University professor, Iowa State University, Ames, IA
Associate professor, Iowa State University, Ames, IA
(Received 22 July 1999; accepted 20 June 2001)
The use of scrap tires as construction materials in civil engineering applications is one of the most promising ways of recycling this troublesome waste material. Design of scrap tire structures, however, requires data on engineering characteristics of tire-derived materials. Confined compression, direct shear, and triaxial tests were carried out to evaluate the mechanical characteristics of tire chips approximately 2 to 10 mm in size. These test results were synthesized with data from previous shredded tire studies to generate empirical relationships between normal stress and direct shear strength and between confining pressure and initial tangent modulus from triaxial testing. It was found that the shear strength of shredded tires is independent of the particle size of the material, and the strength envelope is a power function for normal stresses from 0 to 90 kPa. The initial tangent modulus relates to confining pressure through a quadratic equation, and the lateral strain ratio is independent of confining stress.
Paper ID: GTJ11078J