Abstract: Researches show that the particle morphology has a significant effect on the macro-mechanical properties of gravel aggregates. Accurately describing the morphological characteristics of particles is the foundation work for studying the macro-mechanical behaviour of materials from a micro-mesoscopic level. Firstly, the quantitative characterisation parameters of particle morphology were discussed based on the three-scale morphological characteristics of particle shape, angularity and surface texture. Then, the distribution rule of these parameters was analysed for different grain groups. Finally, the relationship between the particle morphology characteristics and the stacking porosity was discussed. The main conclusions are 1) The proposed quantification parameters with the perimeter as the core characterisation can better reflect and distinguish the particle morphology, as well as its shape, angularity and surface texture; 2) According to the statistical analysis of 1 000 particle samples in each group, the parameters describing the particle morphology, shape, angularity and surface texture all conform to a logarithmic normal distribution; 3) The comprehensive angularity index and surface texture index of particle aggregates present a good mapping relationship with the stacking porosity in both loose and dense states, and they are the main controlling factors on stacking porosity.

Key words: gravel, morphology characteristics, shape, angularity, surface texture, porosity