Effect of coarse aggregate size on non-uniform stress/strain and drying-induced microcracking in concrete
Peng Gao (South China University of Technology)
Yang Chen (Guangdong Low Carbon Technologies Engineering Center for Building Materials, South China University of Technology)
Haoliang Huang (Guangdong Low Carbon Technologies Engineering Center for Building Materials, South China University of Technology)
Zhiwei Qian (FEMRIS)
Erik Schlangen (TU Delft - Materials and Environment)
Jiangxiong Wei (Guangdong Low Carbon Technologies Engineering Center for Building Materials, South China University of Technology)
Qijun Yu (South China University of Technology, Guangdong Low Carbon Technologies Engineering Center for Building Materials)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
Non-uniform stresses, strains and microcracking of the concretes with three coarse aggregate sizes (5–10 mm, 10–16 mm, 16–20 mm) dried under 40% relative humidity (RH) for 60 days were quantified using digital image correlation and lattice fracture modelling. The influencing mechanism of coarse aggregate size on the drying-induced microcracking of concrete was clarified: (1) As the coarse aggregate size decreases, propagation paths of microcracking are increased, which increase the number of small microcracks and release the drying shrinkage force from mortar phase. (2) Tensile stress shells surrounding the coarse aggregates become thinner, thereby decreasing the area of large microcracks. As the coarse aggregate size decreased from 16-20 mm to 5–10 mm, the average thickness of tensile stress shells decreased from 2.13 mm to 1.09 mm at the beginning of drying, and the area of the microcracks >5 μm in width decreased from 796.6 mm2/m2 to 340.2 mm2/m2 at 60 days since drying.