Research on hoop capacity of composite foundation of discarded rubber tires.

In order to improve the availability of waste rubber tires and bearing capacity of sand foundation, a new composite foundation transforms the tensile strength of a discarded rubber tire into a hoop-tightening force on granular sand soil, i.e. hoop capacity, is introduced and investigated. Considering the characteristics of the circular enclosed structure of the tire, the tensile strength of the tire strips was obtained by carrying out a tension test of tire strips, and the relationships between earth pressure, settlement and vertical load were discovered by the results of loading tests under the conditions of confined and unconfined. The distribution of circumferential stress at each position of the tire cross section was monitored to evaluate the contribution of each part of the tire to the integral hoop capacity. Based on the theory of annular elasticity, Airy stress-state function is introduced to determine the solutions of stress, strain and displacement in the sand and tire regions based on the stress boundary condition and displacement continuity condition. The results show that the theory prediction curve has a high precision approaching the measured data, which indicates the rationality of the proposed theoretical model in predicting the circumferential stress of this type of waste rubber tire composite foundations. [ABSTRACT FROM AUTHOR]