Research On Fine Modeling Theory And Method In Steel Reinforced Concrete Structures

The steel reinforced concrete (SRC) structure is one of the most important forms of the steel-concrete composite structures. Because of its advantages of high bearing capacity, stiffness and ductility, it is widely used in various high-rise buildings and super high-rise buildings, such as SRC frame-RC tube.The fine bond behavior between steel and concrete is the base of cooperation of the different materials. Steel, bar and concrete have to cooperate work which can give full play to the advantages of SRC , in order to prevent a variety of external effect. The bond behavious directly affect the bearing capacity, failure modalities, crack, deformation and calculating method etc of this kind of structure.This paper presents a fiber beam-column element for SRC member that explicitly accounts for the slip between the steel and the surrounding concrete, based on force-based formulations and fiber-section method. The bond slip between steel and concrete is considered in section level, which is considered the deformation discrepancy between steel and concrete, through the double cross section is assumed. According to the internal force distribution of SRC beam free body, the equations of equilibrium and compatibility are established based on the basic assumption small deformation. According to the principle of minimum potential energy, the flexibility matrix and the analytical for element state determinations are proposed. Based on the nonlinear beam-column element in Opensees, the programme method is studied. In the end, the applicability and veracity of the method are validated and the deficiencies of element are analyzed, which lay a foundation for the the modeling analysis of the structures in the following.