In this master's thesis we deal with the analysis of the formation and propagation of cracks in a reinforced concrete element that is exposed to the short-term tensile load. For this purpose, we made and tested three reinforced concrete elements with rectangular cross-section of 10,8/7,2 cm and length of 80 cm. In one element longitudinal reinforcement was continuously guided, while in the other two we carried out the lap splice at different lengths. In all specimens, we also installed stirrups in order to prevent the appearance of splitting of the concrete cover. After tensile tests were carried out, a numerical model, developed in research work at the KMLK and KM, was used for simulating the cracking of the elements and then we compared the results with the experimental observations. We have found that by using the numerical model we can simulate the formation and propagation of transverse cracks sufficiently precisely, but we cannot simulate the appearance of splitting cracks and their effect on the tensile load capacity. They can be taken into account indirectly by appropriate bond stress – slip relationship between the reinforcement and the concrete in the lap splice area. In addition, we have found that with confinement, the splitting of the concrete cover in the lap splice area of the longitudinal reinforcement can be prevented or at least mitigated.
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