On May 17th, Géotechnique, the top international journal of geotechnical engineering, published the latest research results on three-dimensional reconstruction and multi-scale characterization of the sand particle morphology by Zhou Bo and Wang Huabin in the school of Civil Engineering and Mechanics This paper is entitled "Three-dimensional sphericity, fractal dimension of sand particles". The first author affiliation of this paper is Huazhong University of Science and Technology. In this paper, Zhou Bo (Assistant Professor) is the first author, Zhou Bo and Wang Huabin (Professor)are co-corresponding authors, and the second author Wang Jianfeng (Associate Professor) is from the Department of Architecture and Civil Engineering in Hong Kong City University.

The research group firstly obtained the three-dimensional (3D) morphological information of two kinds of sand particlesincluding the off-shore quartz sand and weathered granite residual sand by high-precision X-ray CT scanning and image processing. The spherical harmonic (SH) function was then used to reconstruct the accurate 3D morphology of these sand particles. Based on the SH-reconstructed particle surface, practical methods were proposed to calculate the 3D sphericity, roundness and fractal dimension of the sand particles. As a result, these parameters can be used for the characterization and quantification of the multi-scale morphological features of the sand particles. This study has been highly praised by Géotechnique's well-known reviewers: "This paper is a very welcome contribution to the field of morphological analysis of geomaterials. I would be very happy to see the work published. ". Established in 1948, Géotechnique is the world's premier geotechnics journal, publishing research of the highest quality on all aspects of geotechnical engineering.

In recent years, with the development and application of high precision industrial CT technology and numerical simulation technology in geotechnical engineering, the observation of the physical and mechanical behaviors of geomaterials at mesoscopic scale has become a frontier research topic in this field. The study onthe particle morphology of natural sands has become one of the hot and difficult problems in geotechnical engineering. The particle morphology has widely been acknowledged as the primary factor affecting the mechanical properties of sands under low stress conditions. The 3D reconstruction and characterization are the prerequisites for quantifying this morphological effect. Recently, the research interests of Dr. Zhou Bomainly focused on the high-precision CT scanning, image analysis, mathematical representation, and3D characteristic parameters of the 3D particle morphology granular geomaterials; and the application advanced numerical simulation methods and 3D printing technology in geotechnical engineering. A large amount of original findings and resultswere published in high-quality journals in geological and geotechnical fields, such as Engineering Geology, International Journal for Numerical and Analytical Methods in Geomechanics. The research work wassupported by two research grants from the National Science Foundation of China and the key project of the 12th five-year plan of the ministry of science and technology.

The link of this paper: http://www.icevirtuallibrary.com/doi/abs/10.1680/jgeot.16.P.207