建筑固废再生粒料基层填料动回弹模量特性及统一预估模型研究  

Investigating resilient modulus characteristics and developing unified prediction model of unbound aggregate base materials recycled from construction and demolition waste

作　　者：肖源杰 孔坤锋[1,3] 姜钰 华文俊 朱宏伟 蔡德钩 刘宇飞 XIAO Yuanjie;KONG Kunfeng;JIANG Yu;HUA Wenjun;ZHU Hongwei;CAI Degou;LIU Yufei(School of Civil Engineering,Central South University,Changsha,Hunan 410075,China;Ministry of Education(MOE)Key Laboratory of Engineering Structures of Heavy-haul Railway,Central South University,Changsha,Hunan 410075,China;Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中南大学重载铁路工程结构教育部重点实验室,湖南长沙410075 [3]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081

出　　处：《岩石力学与工程学报》2022年第11期2337-2352,共16页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52178443,U1934209,51878673)。

摘　　要：动态回弹模量是重复交通荷载作用下路基填料的重要力学性能指标和力学法路面结构设计的关键参数。为深入研究不同土性参数和应力状态组合条件下城市建筑拆除固废再生骨料的动回弹模量特性,针对单一来源建筑固废再生骨料分别开展5种不同级配、3种不同含水率、3种不同压实度和15级不同应力状态序列下的室内循环加载三轴压缩试验,分析土性参数和动应力水平对动回弹模量的影响规律,进而采用基于平移因子函数的主曲线方法构建综合考虑不同因素的动回弹模量统一预估模型并加以验证。研究结果表明,建筑固废再生骨料的动回弹模量随压实度的降低或含水率的增加而逐渐减少,随粗颗粒相对含量的增多而逐渐增大;动偏应力和围压水平对压实后的再生骨料动回弹模量的影响均较大,且围压的影响更显著;所构建的统一预估模型可同时考虑多个因素的影响且精度更高。研究结果可为建筑固废再生骨料在粒料基层中的资源化高值应用提供理论依据和研究基础。Resilient modulus(MR)is an important mechanical performance indicator of unbound granular pavement materials subjected to repeated traffic loads,as well as a key input parameter of mechanistic pavement analysis and design.In order to investigate MR characteristics of unbound aggregate materials(UAMs)recycled from construction&demolition waste(CDW)under different combinations of influencing index properties and stress states,laboratory repeated load triaxial tests were conducted on UAMs recycled from single-source CDW,of which five different gradations,three different moisture content levels,three different compaction levels,and 15 different loading sequences were properly designed.The effects of index properties and stress states on MR were analyzed,and a unified MR prediction model was developed and further validated by using the shift factor and master curve concepts to incorporate multiple influencing factors.The laboratory testing results show that resilient modulus of UAMs recycled from CDW gradually decreased with decreasing degree of compaction or increasing moisture content and increased with increasing relative content of coarse particles.Both deviator stress and confining pressure affected resilient modulus of UAMs with the effect of confining pressure being relatively more significant.The unified MR prediction model developed can consider all the influencing factor while yielding satisfactory accuracy.The findings could provide theoretical basis and lay solid foundation for resource-conserving and value-added engineering applications of UAMs recycled from CDW in unbound granular pavement layers.

关 键 词：道路工程 建筑固废 再生骨料 动回弹模量 土性参数 应力水平 统一预估模型 

分 类 号：U416.2[交通运输工程—道路与铁道工程]