Mesoscopic modeling method of concrete based on statistical analysis of CT images

• Published in: Construction & building materials 2018-12, Vol.192, p.429-441
• Main Authors: Liu, Tiejun, Qin, Shanshan, Zou, Dujian, Song, Wen, Teng, Jun
• Format: Article
• Language: English
• Subjects: Aggregates (Building materials); Analysis; Coarse aggregate shape; Concrete; Concrete cracking; Concretes; Mechanical properties; Meso-scale modeling; Random aggregate generation; Stress concentration; Tomography; X-ray computed tomography
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2018.10.136

•Actual coarse aggregate shapes were statistically analyzed based on CT technology.•A Polygon aggregate modeling method was proposed considering statistical features.•Proposed polygon aggregate models were verified by an experimental test.•Several meso-scale models with various sizes and cross-section shapes were provided. Few efforts have been made to study actual coarse aggregate shapes in mesoscopic simulation analysis, whereas it has a significant impact on stress distribution and micro-crack propagation during the failure process of concrete. In this study, the true characteristics of aggregates (i.e. edge number, area, equivalent radius, elongation ratio and size distribution) were statistically analyzed by processing the real 2D slice images of concrete obtained from X-ray computed tomography technology. A polygon random aggregate modeling method, considering above statistical features of aggregate, is proposed and verified by an experimental investigation. The test results show that the established model can give an accurate description of the stress-strain behavior and damage evolution of concrete. Moreover, several representative meso-scale concrete models were established, which provides a reference in building meso-scale models with various sizes and cross-sectional shapes, especially for large-scale concrete members that are unable to undergo CT testing due to limitation of operational space.