摘要
为了研究块石填料摊铺层在振动压实过程中的行为及其效应,采用离散元法进行了两种不同荷载工况下的振动碾压模拟试验:“慢速小激振力”和“快速大激振力”。通过对比分析这两种工况下块石填料的颗粒位移、应力响应、颗粒间空隙率变化以及压实过程,结果表明:增加碾压遍数显著增大了颗粒位移,并减少了颗粒间的空隙率;摊铺层表面沉降率与颗粒空隙率的变化值之间表现出强烈的线性相关性;压实能量的作用效应(包括颗粒位移、空隙率减少程度、峰值动应力和静土压力增量)随着摊铺层深度的增加而迅速减弱,压实能量主要沿竖直方向传播,摊铺层沿深度方向可分为主压实区、次压实区和弱影响区3个区域;大粒径块石填料颗粒的比例显著影响颗粒间的接触结构特征,从而影响压实效果和过程,块石填料的压实过程是由挤压压实效应、移动压实效应和填充压实效应共同作用引起的;在持续的振动碾压荷载作用下,颗粒间的接触结构特征和聚集状态从“单点接触”和“松散”状态逐渐演变为“多点接触”和“紧密”状态。研究成果可为工程实践提供重要的理论依据,有助于确定最适摊铺层厚度及优化压路机参数的选择。
Block stone fillers are commonly used for the paving layer of the road.To study the vibration compaction process and effect of the paving layer with block stone fillers,the vibration compaction tests were conducted by discrete element method under two loading conditions of“slow small vibration force”and“fast large vibration force”.The particle displacement,stress response,inter-particle void ratio,and compaction process of block stone fillers under the two loading conditions were compared and analyzed.The results show that increasing the number of compaction passes can significantly increase the particle displacement and reduce the inter-particle void ratio,indicating that the surface settlement rate of the paving layer has a strong linear correlation with the inter-particle void ratio.The effect of compaction energy(such as particle displacement,reduction degree of void ratio,peak dynamic stress,and increment of static soil pressure)decreases rapidly with the increase of the depth.The compaction energy mainly propagates in the vertical direction,so the paving layer can be divided into three zones along the depth,namely,the main compaction zone,the secondary compaction zone,and the weak influence zone.The content of large-sized block stone particles significantly affects the contact structure characteristics,thereby influencing the compaction effect and compaction process.The compaction process of block stone particles is manifested as the combined effects of squeezing compaction,moving compaction,and filling compaction.Under the continuous vibration compaction load,the contact structure characteristics and particle aggregation state of block stone particles will gradually change from“single-point contact”to“multi-point contact”,and from“loose”to“compact”.The research results can provide a preliminary theoretical basis for the determination of maximum paving layer thickness and selection of roller parameters in engineering practice.
作者
徐平
何嘉雄
乔世范
董辉
陈宾
侯伟琦
XU Ping;HE Jiaxiong;QIAO Shifan;DONG Hui;CHEN Bin;HOU Weiqi(College of Civil Engineering,Xiangtan University,Xiangtan 411105,China;Key Laboratory of Geotechnical Mechanics and Engineering Safety of Hunan Province,Xiangtan University,Xiangtan 411105,China;School of Civil Engineering,Central South University,Changsha 410075,China)
出处
《水资源与水工程学报》
北大核心
2025年第1期163-173,共11页
Journal of Water Resources and Water Engineering
基金
国家自然科学基金项目(42272304)
湖南省教育厅资助科学项目(22C0046)
湘潭大学博士科研启动项目(21QDZ27)。
关键词
块石填料
振动碾压
压实效应
接触结构特征
压实过程
离散元模拟
block stone filler
vibrational rolling compaction
compaction effect
contact structure characteristics
compaction process
discrete element method
作者简介
徐平(1989-),男,安徽安庆人,博士,讲师,硕士生导师,主要从事环境岩土工程、高填方路基与边坡稳定性控制方面的研究;通讯作者:乔世范(1975-),男,山东莒南人,博士,教授,博士生导师,主要从事环境岩土工程、路基边坡工程、地铁盾构施工风险防控技术等方面的教学和科研工作。
