@article{LI2025, 
author = {Tao LI and Jiajun SHU and Yue LI and Limin WAN and Bingni WU and Zhengding DENG and Jingzhu HUANG and Galindo RUBEN},
title = {Influence of Particle Size on the Creep Behavior of Granular Materials Under Different Deviatoric Stress},
year = {2025},
journal = {Journal of South China University of Technology (Natural Science Edition)},
volume = {53},
number = {10},
pages = {74-85},
keywords = {particle size, granular materials, creep, state evolution, Derec model},
url = {https://www.sciopen.com/article/10.12141/j.issn.1000-565X.240473},
doi = {10.12141/j.issn.1000-565X.240473},
abstract = {As a typical discontinuous medium, discrete granular materials’ creep behavior plays a crucial role in the formation and evolution of geological disasters such as landslides and debris flows. However, systematic research on the interaction mechanism between particle size and deviatoric stress and its impact on creep behavior remains insufficient. To reveal the coupled effects of particle size and deviatoric stress on creep behavior, this study conducted indoor creep tests on silica spherical particles under multiple conditions and systematically analyzed the influence patterns of different particle sizes and deviatoric stresses on the creep characteristics of granular materials. Based on the Derec creep model and experimental results, this study constructed a quantitative computational model of the creep state of granular materials and clarified the regulatory mechanism of particle size on the creep parameters of the system. The results indicate that the creep behavior of granular systems essentially reflects the dynamic balance between internal deformation and resistance to deformation within the particles. Creep parameters significantly influence system creep characteristics by regulating particle slip and creep behavior. Specifically, as particle size increases, the creep value of the system increases markedly, making it more prone to entering a liquid-like flow state. Concurrently, the system’s resistance to deformation declines while exhibiting heightened sensitivity to deviatoric stress. Furthermore, an increase in particle size not only significantly enhances the fluidity of the particle system but also amplifies its sensitivity to changes in deviatoric stress. Particles with larger diameters show a more pronounced response under high deviatoric stress conditions, and the flow characteristics of granular materials are more susceptible to particle size variations. This influence manifests as a positive correlation between particle size and both the system′s initial state parameters and characteristic strain, while exhibiting negative correlations with viscosity coefficient, critical creep velocity, and critical creep stress.}
}