Investigation of geometrical similar and dissimilar beams by fracture mechanics principles

All materials contain flaws and cracks. Over time, these cracks grow under load and become visible. Detection of cracks and damage is important in terms of understanding the reason of such damage and preventing recurrence. The best way to do this is to use the Principles of Fracture Mechanics. To analyze any structure according to the Fracture Mechanics, fracture parameters must be determined first. In this thesis, four different concrete mixtures were prepared. Using mixtures that have gap-graded and continuously graded, notched concrete beams were produced. Determining fracture loads of the samples, analyzes were made with the help of these values according to Two-Parameter Model (IPM) and Boundary Effect Model. In the analysis with the Two-Parameter Model, it was determined that fracture parameters of the samples in the same size are obtained smaller than the samples in different sizes. In the analysis with the Boundary Effect Model, it was observed that fracture parameters of geometrically similar samples and geometrically dissimilar samples are close to each other. Keywords: Concrete, Fracture mechanics, Two-parameter model, Boundary effect model.