Analysis Of The Bearing Capacity Of The Shear Key Of The Prefabricated Assembled Beam

Prefabricated composite beams are increasingly popularized and applied in response to the trend and requirements of national assembly construction and promotion of steel structures.As an important force transmission structure,the precast-cast-in-situ cluster nail shear group key has an important effect on its failure mode,load-bearing mechanism,force transmission mechanism,etc.,which has a significant impact on the assembled composite beam,and further research is urgently needed.This article relies on the Chongqing Natural Science Foundation’s "Research on the Behavior and Calculation Theory of Assembled Composite Beams Double Uncoupled Structures"(cstc2018jcyj AX0509)project,and carried out 4 groups of 9 test pieces prefabricatedassembled cluster nail shear force with stud row as the main research parameter Key launch test,combined with ABAQUS finite element analysis,discussed the assembly and cast-in-place cluster nail shear force mechanism,bearing capacity and ductility,typical failure mode and failure mechanism,and finally proposed the precast-in-place cast under typical failure mode Calculation method of the bearing capacity of the shear key of the cluster nail group.The main work and results are as follows:1.The prefabricated-assembled cluster nail shearing key push-out test was designed and carried out.The failure mode,load-displacement curve,load-slip curve,bearing capacity and stiffness of the cluster nail shearing key were studied.,4 rows of bolts cluster shear keys and mechanical properties of assembled and cast-in-place shear keys;2.Based on the research of the failure mode of cast-in-situ shear bond,combined with the experiments,theoretical analysis and numerical simulation in this paper,the failure mode and failure mechanism of the assembled cluster nail group are discussed in depth.Three failure modes of failure,and further subdividing each type of failure mode into three types of failure modes;3.Based on the principle of conservation of energy,the difference between the bearing capacity of assembly and cast-in-place pegs and concrete is derived and analyzed.Calculation formula of partial failure mode bearing capacity of assembled cluster nails based on key calculation method;4.Based on the experimental research and FEA analysis,the analysis of the influence parameters of the shear capacity of the prefabricated-assembled cluster nails was carried out;the three main failures were the bending shear failure of the studs,the post-concrete failure of the root,and the vertical splitting failure of the pre-cast concrete Nine subdivided failure modes under the model,and proposed structural calculation methods such as bearing capacity calculation and various minimum structural requirements;5.Based on ABAQUS,a test model for the assembly of a real bridge assembly cluster nail group was established,and the formulas,specification formulas and real-state FEA bearing capacity results were compared in this paper,and the practicality of the formulas in this paper was verified.