Ballast crushing probability model considering the influence of particle morphology and size

The non-uniform shape and diverse dimensions exert a substantial influence on the distribution of forces within the ballast, hence affecting its bearing capacity. The objective of this work was to investigate the interrelated impact of particle shape and size on ballast strength, and then construct a prediction model that could estimate the chance of ballast crushing. For these purposes, both three-dimensional scanning and single-particle compression tests were undertaken. The morphology of ballast particles at various scales was comprehensively characterized by computing diverse parameters based on the scanning results. The present study systematically assessed the impact of size, overall shape and roundness on particle crushing behavior and parameters. Then a novel approach was introduced to calculate characteristic strength, taking into account the influence of particle morphology. A ballast crushing probability distribution model was established, which incorporated the Weibull model. The anticipation of ballast crushing probabilities can be achieved within this framework by analyzing particle size and morphology parameters. At last, the actual crushing probabilities were compared to the predicted probabilities for a sample of 50 randomly chosen ballasts. The results revealed that 80% of the particles displayed a deviation of less than 10%, which proved the accuracy of the applied method.