3D mesoscopic modelling on the dynamic properties of coral aggregate concrete under direct tension. (15th April 2021)

• Record Type: Journal Article
• Authors: Wu, Zhangyu; Zhang, Jinhua; Fang, Qin; Yu, Hongfa; Ma, Haiyan
• Is Part Of: Engineering fracture mechanics. Volume 247(2021)
• Publication Date: 2021-04-15
• Subjects: Coral aggregate concrete (CAC) -- 3D mesoscale modelling -- Dynamic direct tension -- TDIF -- Stress-strain relation -- Failure behavior; Fracture mechanics -- Periodicals; Rupture, Mécanique de la -- Périodiques; Fracture mechanics; Periodicals; 620.112605
• DOI: 10.1016/j.engfracmech.2021.107636
• Languages: English
• ISSNs: 0013-7944

Abstract

Graphical abstract: Highlights: 3D mesoscale modelling approach with random shape and distribution of aggregate. Uniaxial direct-tensile properties of CAC under various strain rates. Failure process, final failure pattern and stress-strain curves. Tensile strength, elastic modulus, critical strain and energy absorption capability. Tensile constitutive relations of CAC under different strain rates. Abstract: The pre-existing studies of the dynamic tensile properties of coral aggregate concrete (CAC) are mainly performed through the splitting-tensile tests or simulations, which have certain discrepancies with the direct tensile properties. This paper employs a 3D mesoscale modelling approach considering the random characteristics (shape and distribution) of coarse aggregates to simulate the uniaxial direct-tensile behaviors of CAC. The dumbbell-shaped specimen model consisting of tri-phase components (aggregate, mortar and ITZ) was established for the numerical simulation of CAC under direct tension at different strain rates (10 −5 to 100 s −1 ). Then the failure pattern and micro-cracking process at different strain rates were simulated, and corresponding stress-strain curves were subsequently obtained and analyzed. Besides, the effect of strain rate on the tensile properties, such as strength, elastic modulus, critical strain, and energy absorption capability, were quantitatively analyzed and discussed. And corresponding strain-rate effect laws were determined and validated by the available test results. Moreover, based on the tensile stress-strain relations of CAC, the tensile constitutive relations of CAC at different strain rates were finally obtained, which is of great significance for further investigation of the dynamic tensile properties of CAC. Most of all, the simulation results remain a good agreement with the existing test results, which demonstrates that the proposed 3D mesoscale modelling approach could be regarded as a powerful tool in simulating the direct-tensile behavior and understanding corresponding damage mechanism of CAC.