摘要
自密实混凝土充填层是CRTSⅢ无砟轨道结构关键结构部件,而目前鲜见新拌混凝土灌注施工参数对充填层施工质量的影响研究。本文依托某客专线下工艺性揭板试验对新拌混凝土灌注施工参数对充填层施工质量的影响进行研究,利用图像分析软件对板面缺陷大小及分布特征进行统计分析,并对充填层自密实混凝土灌注质量进行表征。研究结果表明,拌合物扩展度对自密实混凝土匀质性及表面缺陷影响较大;当混凝土拌合物工作性良好,灌注时间对充填层自密实混凝土匀质性影响不大,但灌注时间对板面缺陷影响较大。现场条件下最佳混凝土拌合物状态及灌注工艺为:拌合物扩展度范围620~670 mm;T500为3~6 s;灌注时间6~8 min。
Self-compacting concrete filling layer is a key structural component of CRTS III ballastless track structure,but there is little research on the influence of fresh concrete pouring construction parameters on the construction quality of selfcompacting concrete filling layer. Based on the technological plate opening test under a special line,the influence of fresh concrete pouring construction parameters on the construction quality of filling layer is studied,and the size and distribution characteristics of slab defects are statistically analyzed by using image analysis software. At the same time,the pouring quality of self-compacting concrete in filling layer is characterized. The results show that the expansion of mixture has a great influence on the homogeneity and surface defects of self-compacting concrete. When the workability of concrete mixture is good,the pouring time has little effect on the homogeneity of self-compacting concrete,but the pouring time has a great influence on the surface defects of self-compacting concrete. It is obtained that the best concrete mixing state and pouring technology under the field conditions are as follows: the expansion range of the mixture is 620 ~ 670 mm,the range of T500 is 3 ~ 6 s,and the pouring time is 6 ~ 8 min.
作者
刘敏杰
刘赞群
李文旭
LIU Minjie;LIU Zanqun;LI Wenxu(Jing-Bin Railway Passenger Dedicated Line Co.Ltd.,Tianjin 300450,China;Central South University,Changsha Hunan 410075,China)
出处
《铁道建筑技术》
2021年第8期1-5,共5页
Railway Construction Technology
基金
国家自然科学基金项目(51378508)。
关键词
自密实混凝土
轨道充填层
匀质性
缺陷率
施工参数
试验
self-compacting concrete
track filling layer
homogenization
defect rate
construction parameter
test
