Influence of wind-blown sand content on the mechanical quality state of ballast bed in sandy railways  

作　　者：Yihao Chi Hong Xiao Zhihai Zhang Yang Wang Zhongxia Qian Weize Zhao 

机构地区：[1]School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China [2]Beijing Key Laboratory of Track Engineering,Beijing Jiaotong University,Beijing 100044,China

出　　处：《Railway Engineering Science》2024年第4期533-550,共18页铁道工程科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No. 52372425);the Fundamental Research Funds for the Central Universities (Science and Technology Leading Talent Team Poject) Grant No. 2022JBXT010。

摘　　要：During the operation of sandy railways, the challenge posed by wind-blown sand is a persistent issue. An in-depth study on the influence of wind-blown sand content on the macroscopic and microscopic mechanical properties of the ballast bed is of great significance for understanding the potential problems of sandy railways and proposing reasonable and adequate maintenance and repair strategies. Building upon existing research, this study proposes a new assessment indicator for sand content. Utilizing the discrete element method(DEM) and fully considering the complex interactions between ballast and sand particles, three-dimensional(3D) multi-scale analysis models of sandy ballast beds with different wind-blown sand contents are established and validated through field experiments. The effects of varying wind-blown sand content on the microscopic contact distribution and macroscopic mechanical behavior(such as resistance and support stiffness) of ballast beds are carefully analyzed. The results show that with the increase in sand content, the average contact force and coordination number between ballast particles gradually decrease, and the disparity in contact forces between different layers of the ballast bed diminishes. The longitudinal and lateral resistance of the ballast bed initially decreases and then increases, with a critical point at 10% sand content. At 15% sand content, the lateral resistance is mainly shared by the ballast shoulder. The longitudinal resistance sharing ratio is always the largest on the sleeper side, followed by that at the sleeper bottom, and the smallest on the ballast shoulder. When the sand content exceeds 10%, the contribution of sand particles to stiffness significantly increases, leading to an accelerated growth rate of the overall support stiffness of the ballast bed, which is highly detrimental to the long-term service performance of the ballast bed. In conclusion, it is recommended that maintenance and repair operations should be promptly conducted when the sand content of the

关 键 词：Sandy railway Wind-blown sand content Discrete element method(DEM) Macroscopic and microscopic mechanical properties Maintenance and repair strategies 

分 类 号：U213.71[交通运输工程—道路与铁道工程]