摘要
生产、运输和振捣会造成道路混凝土不同程度的离析,为解决离析尚无严格评价方法和定量判定标准的问题,设计了道路混凝土离析程度的评价试验,提出评价道路混凝土的离析状况的方法和指标。试验分析了混凝土内部颗粒的分布特征,基于数字化图像处理方法和新拌混凝土粗骨料在体积空间内均匀分布的假设,建立了混凝土粗骨料粒径的径向(试件纵剖面的垂直方向)连续分布模型。在此基础上,提出了表征道路混凝土内部颗粒离析程度的评价参数———离析度。计算了试件不同层位的粗骨料含量,对离析度进行了求解,并结合离析试件的强度、粗骨料层间分布情况给出了评价离析度的参考标准。
Production, transportation and vibration of road concrete usually result in different segregation. To deal with the problem that there is no strict evaluation method and quantitative determination standard, an experiment to evaluate the segregation degree of road concrete was designed, and the status and index of segregation were proposed too. The distribution character of granules in road concrete was analyzed through the experiment. Based on the method of digital image processing and the assumption that coarse aggregate in fresh concrete conform to uniform distribution, a continuous distribution model of coarse aggregate size of concrete sample in vertical direction of longitudinal section was established. The concept of segregation degree--an evaluation parameter to characterize the segregation degree of granules in road concrete was proposed. The content of coarse aggregate at different layers was counted, which was used to calculate the value of segregation degree. Combined with strength of specimen and distribution status of coarse aggregate, a reference criteria to evaluate segregation degree was given.
出处
《公路交通科技》
CAS
CSCD
北大核心
2012年第1期23-27,33,共6页
Journal of Highway and Transportation Research and Development
基金
交通运输部西部交通建设科技项目(200731822301-7)
关键词
道路工程
混凝土
径向连续分布模型
离析度
road engineering
concrete
radial continuous distribution model
segregation degree
