Grading and frequency dependence of the resilient modulus of ballast
The stress-strain and degradation response of railway ballast to imparted train loading is often largely dominated by intrinsic properties, including particle size and particle-size distribution (PSD). To investigate these aspects, a series of large-scale triaxial cyclic tests were conducted on railway ballast. To investigate the influence of grading and frequency on the resilient modulus of railroad ballast, laboratory data from previous work were analysed and discussed. It was observed that the resilient modulus of ballast decreased with an increase in the coefficient of uniformity and cyclic loading frequency. However, for samples with the constant coefficient of uniformity, the resilient modulus appeared to decrease as the particle size and the associated broadness increased. It was also found that the resilient modulus underwent substantial reduction with the evolution of particle breakage by shifting the initial PSD to a broader range.