文档摘要:为解决铁路列车运行引发的路基与地基振害问题,基于阻尼耗能原理设计一种新型橡胶颗粒改良流态粉煤灰(FAR)路基.通过室内配合比试验,制备满足工程路用性能要求的FAR路基材料;采用瞬态激振方法测试FAR路基材料的阻尼比,分析橡胶颗粒掺量对FAR路基材料阻尼特性的影响规律,揭示FAR路基的阻尼耗能机理;采用COMSOL有限元软件建立轨道-路基-地基三维耦合数值模型,对比研究普通路基与橡胶颗粒掺量为5%、10%和15%的FAR路基动应力和振动加速度的传播规律,分析验证FAR路基的隔振性能.研究结果表明:橡胶颗粒的掺入降低了FAR路基材料的强度和干密度,掺量不超过固体混合料质量的15%时,路基基本物理力学性能可满足铁路工程应用要求.橡胶颗粒的黏弹特性使FAR路基内部动应力发生损耗或衰减,路基阻尼比随橡胶颗粒掺量增加而增大,且橡胶颗粒掺量相同时,橡胶颗粒粒径越小FAR路基的阻尼比越大,推荐采用150目橡胶颗粒.相比普通路基,FAR路基基床底层、路基土体和地基土体的动应力均有减小,衰减幅值为10%~30%,可有效避免路基动弹变形、地基振陷等灾害发生;FAR路基振动主频范围内地面振动加速度级减小2~6dB,最高达到83dB,验证了新型FAR路基的良好隔振性能.研究结果可为铁路FAR路基的隔振设计与铁路路基的安全运营提供参考.
Abstract:Inordertosolvetheproblemofsubgradeandfoundationvibrationdamageinducedbyrailwaytrainoperation,anewtypeofflowableflyashsubgradeimprovedbytherubberparticles(FAR)wasdesignedbasedontheprincipleofdampingenergydissipation.TheFARsubgradematerial,satisfyingtherequirementsoftheengineeringperformance,waspreparedbylaboratorymixturetests.Byusingthetransientvibrationexcitationmethod,thedampingratiooftheFARsubgradematerialwastested,theinfluenceoftherubberparticlesonthedampingcharacteristicsofFARsubgradematerialwasanalyzed,andthedampingenergydissipationmechanismoftheFARsubgradewasrevealed.A3Dcouplednumericalmodeloftrack-subgrade-foundationwasestablishedbyCOMSOLfiniteelementsoftware.ThedynamicstressandvibrationaccelerationpropagationlawsoftheFARsubgradewhentherubberparticlecontentwas5%,10%and15%werecomparedwiththoseoftheordinarysubgrade,andthevibrationisolationperformanceoftheFARsubgradewasanalyzedandverified.TheresultsshowthatthestrengthanddrydensityoftheFARsubgradematerialarereducedwiththeadditionoftherubberparticles,andthebasicphysicalandmechanicalpropertiesofthesubgradecansatisfytherequirementsofrailwayengineeringapplicationswhentherubberparticlecontentdoesnotexceed15%ofthesolidmixturemass.TheviscoelasticcharacteristicsoftherubberparticlescancausethelossorattenuationofthedynamicstressintheFARsubgradeandthesubgradedampingratioincreaseswiththeincreaseoftherubberparticles.Whentherubberparticlecontentisthesame,thesmallertherubberparticlesizeis,thelargerthedampingratiooftheFARsubgradewouldbe.Onthisbasis,themixturewith150meshrubberparticleswasrecommended.Ascomparedtotheordinarysubgrade,thedynamicstresslevelsinthesubgradebedbottomlayer,subgradesoil,andfoundationsoiloftheFARsubgradeallreduce,andtheattenuationamplituderangesfrom10%to30%,whichcaneffectivelyavoidreducingtheoccurrenceofthesubgradedynamicdeformation,foundationvibrationsettlementandotherproblems.InthemainfrequencyrangeoftheFARsubgradevibration,thegroundvibrationaccelerationlevelisreducedby2to6dBingeneralwhileitcanreachashighas83dB,whichverifiesthegoodvibrationisolationperformanceofthenewFARsubgrade.TheresearchresultsprovidereferenceforthevibrationisolationdesignandthesafeoperationoftherailwayFARsubgrade.
作者:厉超 李文杰 顾玉仑 张思峰 李书俭 张宇轩 Author:LIChao LIWenjie GUYulun ZHANGSifeng LIShujian ZHANGYuxuan
作者单位:山东建筑大学交通工程学院,山东济南250101山东省路桥集团有限公司,山东济南250014
刊名:铁道科学与工程学报 ISTICPKU
Journal:JournalofRailwayScienceandEngineering
年,卷(期):2024, 21(6)
分类号:TU435
关键词:流态粉煤灰 橡胶颗粒 铁路路基 隔振性能 阻尼比
Keywords:flowableflyash rubberparticles railwaysubgrade vibrationisolationperformance dampingratio
机标分类号:U416.1TU431TU528.041
在线出版日期:2024年7月16日
基金项目:山东省自然科学基金资助项目,山东省交通运输科技计划项目橡胶颗粒改良流态粉煤灰路基隔振性能研究[
期刊论文] 铁道科学与工程学报--2024, 21(6)厉超 李文杰 顾玉仑 张思峰 李书俭 张宇轩为解决铁路列车运行引发的路基与地基振害问题,基于阻尼耗能原理设计一种新型橡胶颗粒改良流态粉煤灰(FAR)路基.通过室内配合比试验,制备满足工程路用性能要求的FAR路基材料;采用瞬态激振方法测试FAR路基材料的阻尼比,分...参考文献和引证文献
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关键词:流态粉煤灰,橡胶颗粒,铁路路基,隔振性能,阻尼比,
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