Application of strength theories in assessing the stress-strain state of steel-concrete structures

Currently, there is a development of high-rise and unique construction, which requires the study of new composite materials, the development of new calculation methods, and the introduction of innovative technologies. Pipe-concrete structures are a successful combination of two completely different materials – steel and concrete, combining their advantages. .In the experimental part, pipe-concrete samples with a length of 100 mm were tested with an axial compressive load. The shell pipe and the concrete core were also tested separately. Based on the results of the experiments, longitudinal deformation diagrams are constructed, which are compared with the deformation of a hollow steel pipe. Stress components in a steel cage and a concrete core are determined using the dependencies of the theory of small elastic-plastic deformations. The applicability of classical strength theories has been evaluated to assess the stress-strain state of a core in a state of triaxial compression and a steel shell experiencing tensile circumferential stresses from the internal pressure of the core on the pipe walls. An experimental evaluation of the obtained results was performed.