The FEM Study On The Bond Strength And Bond-Slip Of Steel Reinforced Concrete Structures

Steel reinforced concrete structure, SRC structure for short, is a main kind of steel and concrete composite structures. SRC structural members have a relatively small sectional dimension and a high bearing capacity. SRC structures obtain a better integral stiffness, and have an excellent seismic properties, So SRC structures are put into application extensively. The bond behavior between steel shape and concrete is the base of their cooperation. The cooperation is the reflection of the advantages of SRC structures. The bond behavior directly affects the bearing capacity, failure modalities, crack, deformation and character methods etc.SRC structure, a novel kind of structure, is studied in this thesis. The author in this thesis has adopted the method of theoretical analysis and numerical simulation calculation and consulted the relative experimental data to analyze the beam-tension simulation model. According to the results of most experiments at home and abroad, steel beam plays less role in the bond between steel shape and concrete than steel edge. Here we just ignore the bond function of steel beam, i.e. we don't consider the bond function of steel beam. The research of this thesis is aimed at offering reference data. Moreover, popularizing such structure is expected. The main research is included as follows:In order to study the influence of the bond-slip factors, this thesis has studied the fourmain bond-anchoring factors——concrete strength, concrete cover thickness, the ratio of steelbar and the transverse hoops. Every factor is analyzed by designing 8 numerical calculation models. Based on the analytical data, the load-slip curve (P--S) of every model is established, and so is the relation curve between factors and bond properties.Then the author has analyzed the strain condition on the bond surface, and established the formula of the strain relations. According to the statistics, the author has put forward a set of formula of the bond-slip constitutive relation, which are easy to understand in physical concept and simple in practice.The result of this research may provide experimental foundation for the improvement of calculating theory of strength, stiffness, deformation and crack width of SRC, and it can be directly applied in the finite-element method analysis of steel reinforced concrete structures. Then by the way of figuring experiment , the strain condition in every situation can be modeled, so the result of theoretical analysis can be improved and perfected. And the resultcan be applied in the project design of ordinary SRC.