Analysis of dynamic displacement of reinforced concrete deep beams made of high strength concrete Part I: Analysis of dynamic displacement of a reinforced concrete deep beam made of high strength C100 grade concrete

The work presented is a three-part set of studies containing a comparative analysis of the displacement state of rectangular concrete deep beams made of concrete of different classes of very high strength, loaded dynamically. The analysis was carried out on the basis of the method presented in this paper [1], which allows for the physical nonlinearity of structural materials: concrete and reinforcing steel to be taken into account. Each part of the work contains the results of numerical solutions of the displacement state of the deep beams separately for the concrete strength of C100 grade, C200 grade, and C300 grade, in each case reinforced with ordinary steel and increased strength steel. Comparative analysis is carried out in Part Two and Part Three, where the results obtained in these parts are respectively compared with the results obtained in the preceding parts. The analysis includes the mutual relations of mechanisms for achieving dynamic load carrying — capacity. The results describing the variation of displacements in time indicate the characteristic features of the deep beam effort and allow for the inference on reaching the state of the dynamic load carrying — capacity. In general, the work confirmed the accuracy of the assumptions and deformation models of concrete and steel as well as the effectiveness of methods of analysis proposed in paper [1] for the problems of numerical simulation of reinforced concrete deep beams behaviour under dynamic loading. The key assumptions used in the analysis are presented in the first part of the paper. The characteristic features of structural materials: concrete and reinforcing steel are presented, taking into account the modified idea of modelling of the dynamic properties of concrete as a material of very high strength. An analysis of the displacement state of rectangular reinforced concrete deep beams made of very high strength concrete of C100 grade under dynamic load for two types of reinforcing steel — ordinary and increased strength — was carried out. Key words: mechanics of structures, reinforced concrete structures, deep beams, dynamic load, physical nonlinearit