Wedge splitting test gained popularity as a stable and simple method to predict the fracture mechanism properties of concrete specimens. The present research focuses on understanding the behavior of self-compacting concrete specimens made with and without steel fibers tested using wedge splitting test, later scanned under high resolution computed tomography. The contribution of hooked end steel fiber and coarse aggregates in fiber reinforced specimens was compared without steel fiber reinforced concrete specimens using high resolution computed tomography. As fracture takes place across the plane perpendicular to the splitting force, i.e. along the depth of specimens. High resolution computed tomography technique was adopted in visualizing the changes taking place across the matrix, coarse aggregate and steel fibers, along with the specimen's depth. Datasets of the images, obtained from computed tomography, after images analysis and volume reconstruction, revealed a higher coarse aggregate and steel fiber participation in the failure region of without and with fibers specimens. Computed tomography investigation indicated a total of 23 coarse aggregate and 64 steel fibers participated in resisting the failure, during wedge splitting test of without and with fibers specimens. Therefore, high resolution computed tomography can be used in understanding, quantifying the participation of coarse aggregate and steel fiber in the failure plane, under fracture loads.

Purpose Fracture properties depend on the type of material, method of testing and type of specimen. The purpose of this paper is to evaluate fracture properties by adopting a stable test method, i.e., wedge split test. Design/methodology/approach Coarse aggregate of three different sizes (20 mm, 16 mm and 12.5 mm), three ratios of coarse aggregate, fine aggregate (CA:FA) (50:50, 45:55, 40:60), presence of steel fibers, and specimens without and with guide notch were chosen as parameters of the study. Findings Load-crack mouth opening displacement curves indicate that for both fibrous and non-fibrous mixes, higher volume of aggregate and higher size of coarse aggregate have high fracture energy. Originality/value For all volumes of coarse aggregate, it was noticed that specimens with 12.5 mm aggregate size achieved highest peak load and abrupt drop post-peak. The decrease in coarseness of internal structure of concrete (λ) resulted in the increase of fracture energy.

PurposeFracture properties of concrete are mainly influenced by specimen shape, size and type of testing method. The study aims to identify the characteristic divergence in fracture – evaluating testing methods, i.e. three-point bend test and wedge splitting test for fibrous self-compacting concrete.Design/methodology/approachA total of nine mixes with three different coarse aggregate sizes (20, 16 and 12.5mm) and three coarse to fine aggregate quantities (40–60, 45–55 and 50–50) were considered to examine the influence of materials on fracture parameters of fibrous self-compacting concrete. For three-point bend test, size effect method was considered to analyze the fracture properties.FindingsThe experimental investigation revealed that fracture energy calculated from wedge splitting test was reasonably on higher side for maximum coarse aggregate-based specimens for all coarse to fine aggregate quantities, while for the size effect method, fracture energy value was maximum for least coarse aggregate sized specimens.Originality/valueThe fracture properties of fibrous self-compacting concrete obtained from wedge splitting test method was higher than the size effect method. This is due to the consideration of only peak load for determining the fracture properties in size effect method analysis.