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| 摘要自密实混凝土（SCC）的工作性能主要受其净浆流变参数的影响，流变参数由净浆的微型坍落扩展度实验结果计算获得。该文基于图像处理技术和智能手机平台，开发了净浆坍落扩展度测量工具。首先，在实验平板上放置预定义的标识；其次，利用图像处理技术和智能手机摄像功能记录净浆流动过程中的图像、时间以及各个时刻标识在图像中的位置信息；最后，利用透视原理和图像处理技术，计算出每帧图像对应的净浆扩展度值，进而得到净浆扩展度与时间的关系，提取相应数据计算该组净浆的流变参数。通过一系列的净浆微型坍落扩展度实验，对该测量工具进行了验证，结果表明：该测量工具可以准确地计算出净浆扩展度和流动时间，与现有方法测量结果一致，适用于净浆微型坍落扩展度实验，为净浆流变参数的获取提供了简便、实用的工具。 |
| 关键词 ：自密实混凝土,净浆,微型坍落扩展度实验,图像处理,智能手机 |
| Abstract：The workability of self-compacting concrete (SCC) is mainly affected by the SCC formulated paste rheological parameters. The paste rheological parameters are obtained from relative mini-slump flow tests. A mini-slump flow measurement tool was developed based on image processing for use on smart phones. First, a predefined mark is placed on the surface of the test plate. Then, the paste spread is imaged over time with the positions of the mark in the images recorded by the smart phone camera found by image processing. Every image of the tests is analyzed to calculate the relative mini-slump flow. The mini-slump flow rate is then calculated with the rheological parameters. The tool was evaluated using a series of mini-slump flow tests. The results show that the mini-slump flow times calculated by the tool are accurate and are nearly the same as those given by the standard method. Thus, this tool is a convenient, effective tool for mini-slump flow tests to obtain the rheological parameters of the paste. |
| Key words：self-compacting concretepastemini-slump flow testimage processingsmart phones |
| 收稿日期: 2016-02-02 出版日期: 2016-12-20 |
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| 通讯作者:安雪晖,教授,E-mail:anxue@tsinghua.edu.cnE-mail: anxue@tsinghua.edu.cn |
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