Strength and deformation characteristics of reinforced rubber, tire chip with and without sand mixtures and its application on reinforced wall simulation | |
| Author | Sompote Youwai |
| Call Number | AIT Diss. no.GE-03-02 |
| Subject(s) | Rubber--Reinforcement Concrete walls |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Engineering, School of Civil Engineering |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. GE-03-02 |
| Abstract | Scrap tires are undesired urban waste, the volume of which is increasing every year. One of the possible use of this waste is to use shredded tires alone or mixed with soil as a lightweight backfill. Two types rubber tire chips was investigated namely: flate-shaped and cubical-shaped particles. The conventional and large triaxial tests on the compacted rubber tire chips with and without sand mixtures have been conducted. The tests were carried out at different mixing ratios of rubber tire chip and sand. With an increasing portion of sand in the mixture, the unit weight of the mixture and the shear strength increased, but the compressibility decreased. The dilatancy characteristics of rubber tire chip with a sand mixture were relatively similar to a cohesionless material and can be explained within the critical state framework. The general strength envelopes of rubber tire chips obtained from triaxial tests were proposed with independent of the particle shape of rubber tire chip. Flat-shaped tire chips has more compressibility than cubical-shaped tire chip. The proposed constitutive model based on critical state framework can broadly capture the strength and deformation characteristics of a rubber tire chip-sand mixture at different mixing ratios. The interaction between rubber tire chip-sand mixtures and the hexagonal wire reinforcement as well as the strength and deformation characteristics of mixtures were investigated by in-soil pullout tests, large-scale direct shear tests and one-dimensional compression tests. With increasing rubber tire chip portion in the mixture, the shear strength and deformation characteristics of rubber tire chip with sand mixture increased and exhibited strain-hardening behavior. Compared with the test results in sand, hexagonal wire reinforcement in the rubber tire chip with and without sand mixtures had lower pullout resistances. However, with increasing sand content in the mixtures, the pullout resistances of hexagonal wire in mixtures increased and the required displacements for fully mobilizing the pullout resistances decreased. The proposed nonlinear empirical equation can successfully predict the pullout resistance of hexagonal wire in rubber tires chip-sand backfill of different mixing ratios. The pullout test model was proposed to simulate the soil and reinforcement interface shear stress.ยท Based on a hyperbolic interface shear stress, the proposed interface model can capture the overall interaction between soil and hexagonal wire reinforcement regarding to the pullout force as well as the displacement along the reinforcement. The total amount of reinforcements required for tire chip backfill for reinforced wall is less than those for sand and rubber-sand backfill. The required embedded length of hexagonal wire in sand and rubber-sand backfill is almost identical, but higher than those in rubber tire chips. The state-dependent dilatancy model for rubber tire chip-sand mixtures has been successfully implemented into the numerical analysis program (FLAC) to perform the parametric study on the behavior of the reinforced wall. With increasing rubber tire chip portion in the mixtures, the lateral wall movement as well as the coefficient of lateral earth pressure increased. From the parametric study, with increasing reinforcement stiffness and the interface shear stiffness, the summation of the tensile force in the reinforcement increased and the lateral deformation of the reinforced wall decreased. The effects of the interface shear stiffness are less to the behavior of a reinforced wall than the stiffness of the reinforcement. |
| Year | 2003 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. GE-03-02 |
| Type | Dissertation |
| School | School of Civil Engineering |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Geotechnical Engineering (GE) |
| Chairperson(s) | Bergado, Dennes T.; |
| Examination Committee(s) | Noppadol Phien-Wej; Barry, William J.;Yasuhara, Kazuya; |
| Scholarship Donor(s) | Government of Japan; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2004 |