Seismic Isolation Effect of Rubber Particle Cushion Layer under Structure-Soil-Structure Interaction

In rural areas of earthquake-prone regions, Low-rise or multi-storey masonry structures and frame buildings suffered severe damage, and this damage increases markedly when adjacent buildings are closely spaced. Research on economical, practical, and environmentally friendly seismic isolation technologies, especially in structure-soil-structure interaction (SSSI), remains insufficient. This study uses rubber particles derived from recycled tires as a seismic isolation cushion and evaluated their performance via shaking table tests. Further analysis demonstrates cushion thickness, input ground-motion type (Sine wave, Wenchuan wave, and EL-Centro wave), and interbuilding spacing all affect seismic isolation performance. Results show that increasing cushion thickness enhances isolation, producing a maximum improvement of 15.6%. The EL-Centro wave produces a larger effect on the building's acceleration amplification factor than the sine and Wenchuan waves, increasing that factor by 2% and 3%, respectively. Increasing spacing between adjacent buildings reduces the acceleration amplification factor, with a maximum decrease of 12.7%. Rubber particle isolation cushions made from recycled waste tires combine excellent seismic isolation performance with clear sustainability benefits. These results provide both theoretical foundation and experimental support for seismic isolation systems that considering structure-soil-structure interaction in rural buildings.