Aggregate shape greatly affects the workability and mechanical properties of concrete. Nevertheless, the irregular shape of aggregate particle defies full definition and measurements. In this article, the particle shape and particle size of crushed limestone coarse aggregate were studied with Digital Image Processing (DIP) method, and the results were compared with the values measured by caliper gauge. Results revealed that the length, width and length-diameter ratio measured by the two methods were almost equal; but the thickness, flatness ratio, sphericity and the grain shape factor obtained by the DIP method varied remarkably. The value of λ was corrected, and the correction factor was 1.82. The deviation of the corrected results was less than 2%.
Key words
crushed coarse aggregate /
digital image processing method /
particle shape /
flatness ratio /
correction factor
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
References
[1] 徐定华,徐 敏.混凝土材料学概论[M].北京:中国标准出版社,2002:244-256.
[2] 孙立国.三级配(全级配)混凝土骨料形状数值模拟及其应用[D]. 南京:河海大学,2005.
[3] MORA C F, KWAN A K H, CHAN H C. Particle Size Distribution Analysis of Coarse Aggregate Using Digital Image Processing[J]. Cement & Concrete Research,1998,28(6):921-930.
[4] ANTOINE R, COURARD L. Perforation Strength of Geosynthetics and Sphericity of Coarse Grains: A New Approach[J]. Geotextiles and Geomembranes,1996,14(10):585-600.
[5] KWAN A K H, MORA C F, CHAN H C. Particle Shape Analysis of Coarse Aggregate Using Digital Imagine Processing[J]. Cement & Concrete Research,1999,29(9):1403-1410.
[6] MORA C F, KWAN A K H. Sphericity, Shape Factor, and Convexity Measurement of Coarse Aggregate for Concrete Using Digital Image Processing[J]. Cement & Concrete Research,2000,30(10):351-358.
PDF(2062 KB)
