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.
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