Study of the Vibration Reduction Performance of Rubberized Self-Compacting Concrete Filling Layer in Prefabricated Slab Track

Abstract

Theoretically, there are two approaches to reducing the vibration induced by railway transit in cities: lowering structural stiffness, often used in subway design to isolate vibration, and absorbing the vibration by improving the damping ability of structural elements, which has rarely been studied. Based on the principle of energy absorption, a new vibration reduction measure—rubberized self-compacting concrete filling layer (RSCCFL)—was presented as a low-cost vibration reduction measure. In this study, the effects of rubber content on workability, compressive strength, and dynamic properties of rubberized self-compacting concrete (RSCC) were studied. The damping enhancement mechanism of RSCC is discussed. The vibration reduction performance of RSCCFL was evaluated by an environmental vibration prediction model. The results showed that incorporating rubber reduced the self-compacting concrete’s workability, compressive strength, and dynamic modulus while increasing the damping ratio. The improvement in damping performance is related to the fact that rubber increased the energy dissipation of stress waves in the matrix. Compared with the self-compacting concrete (SCC) filling layer, RSCCFL had excellent vibration reduction performance, which gradually improved as the rubber content increased. The RSCCFL had a better vibration reduction effect on the environmental vibration above 40 Hz, and the low-frequency vibration (below 20 Hz) was also reduced by about 3–5 dB. In general, the vibration reduction effect of RSCCFL was equivalent to that of the subway primary vibration reduction measures, but it had a higher impact on low-frequency vibration.