Determination of coarse aggregate morphological indices and shape properties by 3d photogrammetry method

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2021-4-8
Rashidzade, Isfandiyar
The morphological properties of the aggregatesplaya crucial role in the performance of the pavements. Therefore, thereexist various empirical methods and image-based approaches that directly or indirectly measure these properties. Image-based approaches are majorly classified as two-dimensional (2D) or three dimensional (3D). It has been reported in many studies that the 3D methods capture the overall aggregate morphological and shape properties more accurately than any 2D alternatives. However, the equipment need in the 3D approaches are expensive and processing durations are extensively long. Therefore, this study aimed to develop a practical and inexpensive 3D photogrammetry based method to overcome the need for 3D imaging equipment. This study introduces a detailed guideline including a testing setup and analysis methodology to measure morphological indices (angularity and form indices) and also shape features (volume, surface area, and diameters).Overall 56 aggregates from basalt, dolomite, limestone, perlite, and river gravel sources that retained on1/2”and 3/8”sieve sizes were analyzed utilizing the proposed 3D and traditional 2D methods.Moreover,sensitivity analysis based on triangulation and angle increments were performed to optimize the time and efficiency of the developed algorithm. Consequently, the analysis revealed that the proposed 3D method is capable to accurately determine the shape features and morphological indices.This method can be successfully utilized as a quality control/assurance method by the construction industry.

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Citation Formats
I. Rashidzade, “Determination of coarse aggregate morphological indices and shape properties by 3d photogrammetry method,” M.S. - Master of Science, Middle East Technical University, 2021.