Seismic isolation performance of layer-bonded scrap tire rubber pads for rural buildings

In this paper, layer-bonded scrap tire rubber pads (LBSTP) were fabricated for foundation isolation of rural buildings using small car scrap tires from three different brands: Dunlop, Michelin, and Bridgestone. Both pressure-shear tests and finite element analysis are carried out on LBSTP at design compressive stresses of 3 MPa, 4 MPa, and 5 MPa to investigate the horizontal mechanical properties and seismic isolation performance. The damage, energy dissipation, and stiffness degradation characteristics of LBSTP are explored. The cumulative hysteretic energy dissipation formula of LBSTP is established from ABAQUS finite element analysis on the compression-shear mechanical behavior of LBSTP specimens, whereby the stress distribution of LBSTP subject to seismic loading is also obtained. The dynamic response of the building designed with LBSTP isolation is also analyzed by using OpenSEES. The results show that isolation of LBSTP specimens can extend the self-oscillation period of the structure from 0.390 to 1.609 s at an acceleration of 300 cm/s2. The acceleration response of the superstructure showed a maximum reduction of 64.6 % and a minimum reduction of 47.3 %. Additionally, the numerical values of acceleration and inter-story displacement angle for each story of a three-story concrete frame structure showed no significant difference after implementing LBSTP isolation. This result indicates that the superstructure has marginal drift ratios and behaves like a quasi-rigid body.