摘要
掌握轮胎衍生骨料(TDA)级配碎石混合料临界状态变化是TDA在道床中安全应用的重要前提,目前对此研究存在不足。通过大型静三轴试验,分析了3种围压、4种TDA体积含量的TDA级配碎石混合的应力-应变特性,研究了围压、TDA含量对TDA级配碎石混合料的临界状态变化影响。结果表明:当TDA体积掺量小于20%时,混合料的剪切特性为应变软化型;当TDA体积掺量大于20%时,混合料的剪切特性为应变硬化型。试验结果分析发现,TDA级配碎石混合料的临界状态线在e-(p’/pa)ζ平面上为直线,并且临界状态参数与TDA体积含量呈现线性变化。因此,基于临界状态理论,通过构建临界状态参数和TDA含量的关系,推导了能够正确描述TDA级配碎石混合料的应力-应变特征和体积变形特征的预测公式。通过预测值与试验值之间的对比,证实了该公式的合理性。
the evolution of the critical state of TDA-graded aggregates is essential to safety for TDA application in railway roadbed,but the investigations on effects of TDA on the critical state are rare.This paper presents an experimental investigation on the stress strain relationship of TDA-graded aggregates through large scale triaxial apparatus by consolidation and drainage conditions.In total,12 groups of specimens were carried out considering four volumetric TDA content and three confining pressures.The experimental results show that the shear properties of the TDA sub-ballast mixture are characterized as strain-softening when the TDA volume content is less than 20%,and show strain hardening when the TDA volume content is greater than 20%.And the critical state line(CSL)in e-(p’/pa)ζspace,and relationship between the TDA content and the values of parameters of CSL is linearity.In consequence,the strain-stress of TDA-graded aggregates based on the critical state line characteristics was predicted,and compared to the corresponding measured values with good agreement.It highlights the feasibility of the new formula for the TDA-graded aggregates.These experimental findings are helpful for modeling aggregates with TDA inclusion.
作者
陈晓斌
杨宁宇
朱禹
张俊麒
乔世范
CHEN Xiao-bin;YANG Ning-yu;ZHU Yu;ZHANG Jun-qi;QIAO Shi-fan(School of Civil Engineering,Central South University,Changsha,Hunan 410083,China;Ministry of Education(MOE)Key Laboratory of Engineering Structures of Heavy Haul Railway,Central South University,Changsha,Hunan 410075,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2021年第4期921-931,共11页
Rock and Soil Mechanics
基金
科技研究开发计划重大课题(中国铁道科学研究院)
国家自然科学基金(No.51978674)。
