基于SmartRock传感技术的含砂道砟直剪试验研究  

Direct shear tests on sand-contaminated ballast based on SmartRock sensing technology

作　　者：王家全[1,2,3] 吴新彪 董程锋 张涛艺 WANG Jia-quan;WU Xin-biao;DONG Cheng-feng;ZHANG Tao-yi(College of Civil and Architectural Engineering,Guangxi University of Science and Technology,Liuzhou,Guangxi 545006,China;Guangxi Zhuang Autonomous Region Engineering Research Center of Geotechnical Disaster and Ecological Control,Guangxi University of Science and Technology,Liuzhou,Guangxi 545006,China;Guangxi University Key Laboratory of Disaster Prevention and Mitigation and Prestress Technology,Guangxi University of Science and Technology,Liuzhou,Guangxi 545006,China)

机构地区：[1]广西科技大学土木建筑工程学院,广西柳州545006 [2]广西科技大学广西壮族自治区岩土灾变与生态治理工程研究中心,广西柳州545006 [3]广西科技大学广西高校防灾减灾与预应力技术重点实验室,广西柳州545006

出　　处：《岩土力学》2025年第4期1060-1070,共11页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52468047);广西自然科学基金重点项目(No.2022GXNSFDA035081);广西高等学校高水平创新团队及卓越学者计划(桂教人才[2020]6号);广西科技大学研究生教育创新计划(No.GKYC202463)。

摘　　要：针对路基填料受细粒污染后研究的不足,对路基填料交界层遭受细粒污染后的含砂道砟(sand-contaminated ballast,SCB)开展了大型直剪试验(direct shear tests,DST)。通过布设无线姿态传感器SmartRock对SCB剪切过程中内部颗粒运动进行监测,结果表明:(1)随着空隙脏污指数(void contamination index,VCI)增大,SCB抗剪强度呈下降趋势,脏污会改变道砟抗剪强度的剪应力-剪应变发展模式,通过幂函数回归方程得到了不同脏污程度下混合料抗剪强度包络图;(2)体应变呈现剪缩-剪胀的变化规律,基于幂函数构建的预测模型可准确描述SCB试件剪缩-剪胀过程中的临界剪应变与峰值体应变;(3)嵌入式无限Smrt Rock传感器可以捕捉剪切面单个颗粒的运动规律。通过直剪试验反映了真实散体道床受列车荷载作用时,砟层内部颗粒的运动模式是多维的,与列车行车方向正交面的散粒体道床内部颗粒间相互作用力可由单向剪切作用表征。A series of large-scale direct shear tests(DST)was conducted on sand-contaminated ballast(SCB)in order to address the paucity of research on subgrade fillers contaminated with sand.Wireless attitude sensors,known as SmartRock,were used to monitor the internal particle movement during the shear process of the SCB.The results show that the shear strength of the SCB decreases with an increase in the void contamination index(VCI),leading to changes in the shape of the shear stress-shear strain curve of the SCB.Additionally,the power function offers a more accurate fit for the peak shear strength envelope diagram of the SCB at various VCI levels.The volumetric strain exhibits a pattern of shear compression-dilation,and the power function better predicts the critical shear strain and peak volumetric strain in the shear compression-dilation process of the SCB specimens.The SmartRock sensor can capture the motion pattern of individual particles within the shear plane.The DST accurately reflects the behavior of the real ballast bed under train loading conditions.Moreover,the study shows that the motion pattern of particles within the ballast layer is multidimensional.The interaction forces between particles in the ballast bed,perpendicular to the train travel direction,can be described by unidirectional shear action.

关 键 词：直剪试验 砂污染道砟 SmartRock 运动特性 

分 类 号：TU452[建筑科学—岩土工程]