Evaluation of the influence of linear stress concentrators in reinforced concrete elements using the postulates of fracture mechanics

The article is devoted to the study of linear stress concentrators in reinforced concrete, which, unlike randomly located stress concentrators from a large and medium-sized concrete aggregate (granite or gravel crushed stone), can have a strategic impact on the formation of cracks in a reinforced concrete element in the presence of a sufficient level of tensile stresses. The study is one of the theoretical parts of a significant research program on the cracking of reinforced concrete elements in tension and bending. The description of the process of cracking with the help of fracture mechanics allows us to try to formulate a mathematical apparatus for taking into account stress concentrators linearly located in reinforced concrete elements and their influence on the formation of cracks, in particular, at the moment of cracking in bending elements. Field tests of specimens with artificially created stress concentrators were carried out, including the RILEM method, on the basis of which trial calculations of the cracking moment were carried out using the stress intensity factor.