水泥再生二灰稳定碎石干缩性能影响因素分析  

Analysis of Influence Factors of Drying Shrinkage Performance of Cement Recycled Lime and Fly Ash Stabilized Macadam

作　　者：许红林 郭倩芸 张子谦 周婧 张桐 李根 李艳阳 范立嘉 Xu Honglin;Guo Qianyun;Zhang Ziqian;Zhou Jing;Zhang Tong;Li Gen;Li Yanyang;Fan Lijia(Beijing Ruitong Road&Bridge Maintenance Center Co.,Ltd.,Beijing 100097,China;College of Civil Engineering and Transportation Engineering,Bejing University of Cwil Engineering and Architecture,Beijing 102616,China;Beijing Municipal Road&Bridge Management Maintenance Co.,Ltd.,Beijing 100097,China;Beijing Municipal Road and Bridge Zhengda Road Technology Co.,Ltd.,Beijing 100026,China;General Contracting Department 1 of Bejing Municipal Road and Bridge Co.,Ltd.,Beijing 100161,China;Fangshan Asphalt Plant of Beijing Municipal Road and Bridge Building Materials Group Co.,Ltd.,Beijing 102400,China)

机构地区：[1]北京路桥瑞通养护中心有限公司,北京100097 [2]北京建筑大学土木与交通工程学院,北京102616 [3]北京市政路桥管理养护集团有限公司,北京100097 [4]北京市政路桥正达道路科技有限公司,北京100026 [5]北京市政路桥股份有限公司总承包一部,北京100161 [6]北京市政路桥建材集团有限公司房山沥青厂,北京102400

出　　处：《市政技术》2023年第8期103-109,共7页Journal of Municipal Technology

基　　金：国家重点研发计划(2022YFB2601900);国家自然科学基金项目(51678028,51978034);北京市自然科学基金与北京市教委联合基金项目(KZ202110016020)。

摘　　要：水泥再生二灰稳定碎石实现了废旧二灰稳定碎石基层材料的规模化再生利用,但其强度形成初期易产生干缩裂缝。为解决这一问题,对水泥再生二灰稳定碎石抗干缩性能的影响因素展开研究,首先选取新料及50%、75%和100%的旧料掺配率进行级配设计,测定了不同水泥用量下旧料掺配率对水泥再生二灰稳定碎石7 d无侧限抗压强度及抗干缩性能的影响,确定最佳水泥用量为4.5%;然后在最佳水泥用量下,研究了不同集料粗细比对水泥再生二灰稳定碎石抗压强度及抗干缩性能的影响;最后基于回归分析建立了干缩系数与集料粗细比的回归方程。研究结果表明,随着水泥用量和旧料掺配率的增加,水泥再生二灰稳定碎石的7 d无侧限抗压强度和干缩系数均呈增大趋势;随着集料粗细比的增加,抗压强度呈先增大后减小的趋势,但抗压强度值始终大于规范要求,干缩系数呈先减小后增大的趋势,结合干缩系数与集料粗细比的回归方程,最终确定最佳集料粗细比范围为1.70~1.75,该结果可为水泥再生二灰稳定碎石的设计和施工提供参考。Cement recycled lime and fly ash stabilized macadam realizes the large-scale recycling.But it is easy to produce dry shrinkage cracks in the initial stage of strength formation.In order to solve this problem,the influence factors of the anti-shrinkage performance of cement recycled lime and fly ash stabilized macadam are studied in this paper.Firstly,the new aggregate and 50%,75%and 100%old material blending ratio are selected for grading design.Under different cement dosages,the influence of the old material blending ratio on the 7 d unconfined compressive strength and anti-shrinkage performance of cement recycled lime and fly ash stabilized macadam are measured to determine the optimum cement dosage of 4.5%;Then,under the optimum cement content,the effects of different aggregate coarse-to-fine ratio were studied.Finally,the regression equation of the relationship between the dry shrinkage coefficient and the aggregate coarse-to-fine ratio and the dry shrinkage coefficient is established by the regression analysis.The results show that both the 7 d unconfined compressive strength and dry shrinkage coefficient of cement recycled lime and fly ash stabilized macadam of recycled mixture show an increasing trend with the increase of cement content and old material blending rate;With the increase of aggregate coarse-to-fine ratio,the compressive strength increases first and then decreases.But the compressive strength value is always greater than one of the specification requirements.The dry shrinkage coefficient decreases first and then increases.Combined with the regression equation of dry shrinkage coefficient and aggregate coarse-to-fine ratio and dry shrinkage coefficient,the optimal aggregate coarse-to-fine ratio range is finally determined to be 1.70~1.75.The results can provide reference for the design and construction of cement recycled lime and fly ash stabilized macadam.

关 键 词：道路工程 水泥再生二灰稳定碎石 抗干缩性能 旧料掺配率 集料粗细比 回归分析 

分 类 号：TU521[建筑科学—建筑技术科学]