Experimental investigation on rubber pad-the key component of isolation layer in CRTS III track of high-speed railway

As a buffer member between the self-compacting concrete filling layer and the base slab, the rubber pad achieves the purpose of damping and energy consumption through its own compression deformation. Therefore, the mechanical properties of the rubber pad under plane compression have a significant impact on the seismic characteristics of CRTS III slab ballastless track system. In order to study the mechanical properties of rubber pad under plane compression, a load-displacement mechanical model was established, considering size effect. A group of plane compression tests of rubber pad were designed. The variation laws of load-displacement curve of rubber pad specimens under different section size and thickness were explored. The stiffness variation law of rubber pad specimen under plane compression was discussed. The load-displacement mechanical model of rubber pad was proposed. The results show that the load-displacement mechanical model of rubber pad can effectively simulate the plane compression mechanical characteristics of rubber pad. The shapes of load-displacement curves of different rubber pad specimens are roughly the same, and the displacement increases nonlinearly with the increase of load. The section size and thickness of the rubber pad specimens have a significant effect on the load-displacement curve. Under the same load, the larger the section size and the smaller the thickness, the smaller the displacement of the rubber pad. The secant stiffness of rubber pad specimens are related to the section size and thickness. The larger the section size and the smaller the thickness, the greater the secant stiffness of the rubber pad and the lower the plane compressibility. © 2023, Central South University Press. All rights reserved.