不同形状废旧轮胎橡胶颗粒改良道砟动剪切性能及细观作用研究  

Dynamic shear performance and meso-effect of railway ballast improved with tire-derived aggregate of different shapes

作　　者：常建梅 田世龙 李翔 冯怀平 KUVANDIK Lesov CHANG Jian-mei;TIAN Shi-long;LI Xiang;FENG Huai-ping;KUVANDIK Lesov(School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang,Hebei 050043,China;Hebei Xiongan Beizi Engineering Consulting Co.Ltd.,Xiongan,Hebei 071800,China;Tashkent State Transport University,Tashkent,Uzbekistan)

机构地区：[1]石家庄铁道大学土木工程学院,河北石家庄050043 [2]河北雄安北咨工程咨询有限公司,河北雄安071800 [3]塔什干国立交通大学,乌兹别克斯坦塔什干

出　　处：《岩土力学》2025年第3期721-728,共8页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No.52272439,No.U22A20233);河北省自然科学基金(No.E2023210054)。

摘　　要：废旧轮胎橡胶颗粒(tire-derived aggregate,简称TDA)混合道砟的改良方法,不仅具有减少道砟破碎和降低振动等的优点,而且可缓解日益增长的废旧轮胎处置压力。由于兼具节能、绿色等特点,越来越受到研究人员的关注。然而,目前的研究主要是围绕TDA掺量影响开展室内试验,对其他配置参数影响规律的研究还比较少见。颗粒形状是散粒体岩土材料力学性能的重要影响因素,研究不同形状TDA改良道砟的动力性能和作用规律,是提高认识和促进改良方法应用的必要基础工作。基于相同TDA掺量和孔隙比,在道砟中分别混合块状、针状和片状TDA,开展了室内动三轴试验和离散元模拟,对比分析了改良道砟的宏观试验结果和细观作用规律。结果表明:针、片状TDA改良道砟的轴向累积应变小于纯道砟试样,块状TDA改良道砟的轴向应变大于纯道砟;添加针、片状TDA对改良道砟动弹性模量的降低作用小于块状TDA。针状TDA改良道砟的耗散能和阻尼均较大,并呈稳定发展状态;片状TDA改良道砟的阻尼比较小,并随加载次数增加而逐渐减小;由于形状的长细和扁平特征,针、片状TDA主要通过增加橡胶颗粒间的接触提高了配位数,使集料更趋于密实状态;针、片状TDA能够显著抑制颗粒的转动速度和累积转角,并使得试样的累积动变形减小。The method of incorporating tire-derived aggregate(TDA)into ballast not only has the advantages of reducing ballast crushing and vibration but also alleviates the increasing pressure of waste tire disposal.Due to its energy-saving,eco-friendly characteristics,among others,it has increasingly attracted the attention of researchers.However,current research primarily focuses on the effect of TDA content through laboratory tests,with relatively little research on the influence of other parameters.Particle shape is a crucial factor influencing the mechanical properties of granular geomaterials.Studying the dynamic properties and meso-effects of mixtures containing different shapes of TDA is a necessary foundation for enhancing our understanding and promoting the application of these methods.Based on the same TDA content and specimen void ratio,block,elongated,and flat TDA particles were mixed into ballast,and dynamic triaxial tests and discrete element simulations were conducted to compare and analyze the macro-level test results and meso-level effects of the ballast samples.The results show that the cumulative axial strain of ballast mixed with elongated and flat TDA is smaller than that of pure ballast,while the cumulative axial strain of ballast mixed with block TDA is larger than that of pure ballast;the reduction in dynamic elastic modulus caused by elongated and flat TDA is also smaller than that caused by block TDA.The dissipative energy and damping ratio of ballast mixed with elongated TDA are larger and develop stably.The damping ratio of ballast mixed with flat TDA is relatively small and gradually decreases with the number of loadings.Due to their shape characteristics,elongated and flat TDA primarily increase the coordination number between rubber particles,making the aggregate denser.Elongated and flat TDA can significantly inhibit the rotation speed and cumulative rotation angle of the particles,thus reducing the cumulative deformation of the samples.

关 键 词：废旧轮胎橡胶颗粒形状 道砟 动三轴 离散元 

分 类 号：U213[交通运输工程—道路与铁道工程]