The effect of aggregate gradation on concrete fracture energy using the work of fracture method

Abstract

The micro-cracks that commonly occur in concrete structures are a potential source of crack propagation which leads to the possibility of catastrophic failure. Concrete cracks that occur propagating mainly along the interface zone that significantly conditioned by aggregate characteristics. Aggregate characteristics as concrete fillers have a significant role as a strain energy release medium known as fracture energy. This research is using an experimental investigation about the fracture characteristics of concrete using different gradations with a maximum diameter of 25 mm and 20 mm. The experiment includes a compressive strength test and a fracture parameter test. Three-point bend test was selected based on RILEM recommendations to calculate fracture parameters. The result has shown that the aggregate gradations used in concrete mixtures should take into account the effect on compressive strength and total fracture energy. Uniform gradations with smaller maximum sizes have high compressive strength but low fracture energy.