Numerical calculation of steel-concrete structures
Introduction. Steel-concrete structures are composite systems composed of steel beams and a reinforced concrete slab. The reliable transfer of shear forces between the beam and the slab is required for the structure to behave efficiently. Towards this end, anchoring devices are used to ensure a connection between the beam and the slab. The design of a steel-concrete beam, composed of a reinforced concrete slab and steel beams, having bent sections, is considered. The steel-concrete beam is a system of galvanized bent steel beams placed in parallel and partially embedded in the 90 mm thick concrete slab made of B25 concrete. Shear forces are transmitted due to adhesion between galvanized steel and concrete without anchoring devices or the additional treatment of the beam surface. Materials and methods. The samples, whose flat galvanized plate had been embedded in concrete, were tested to identify actual adhesion forces. Finite element models (FEM), developed using various software packages, were assessed. FEM parameters that ensured the accuracy, acceptable for practical use, were identified. Results. The strength of adhesion between the steel plate and concrete was experimentally identified for different options of its attachment to concrete. The mesh pattern was identified for the plate for the case when 3D finite elements were used. Conclusions. A steel-concrete beam with a span of 6-8 m, bent galvanized sections partially embedded in the reinforced concrete slab with a thickness of 90 mm was developed. The author experimentally identified the shear resistance of a galvanized steel plate embedded in concrete, which reached 0.248 to 0.415 MPa depending on how the surface of the steel plate embedded in concrete was prepared. Numerical models were tested using different computational packages designated for the calculation of steel-reinforced concrete beams. The author suggests FEM improvements on the basis of numerical calculation methods applied with due regard for the experimental data obtained during the testing of the full-scale structure.