This report describes three separate studies that examine the deformability of shredded tire fill material:
The first study determined the response of shredded tires to cyclic loading. These tests were conducted in a load frame on both constrained and unconstrained samples and showed that the material became stiffer with increasing load. The second study focused on the long-term creep settlements of constrained and unconstrained samples. The results indicate that creep exists for a period of up to two years after loading. The third study investigated the possible anisotropic properties of the material. A larger modulus of elasticity was found in directions parallel to the layers than in the direction perpendicular to the layers. However, settlements computed using a representative anisotropic shredded tire fill material indicate that the current settlement analysis, based on isotropic shredded tire layers, predicts maximum settlements conservatively.