Numerical Analysis On Seismic Behavior Of RC Beam Composite Steel Tube Confined Concrete Column Joints

The design of the joints of the composite steel tube confined concrete column is oneof the critical technical issues of the frame structure. There are many problems to besettled in the joint of the composite steel tube confined concrete column and reinforcedconcrete beam, such as smaller capability of transmitting force and complex conformation.It is necessary to research mechanical behavior of the joints of the composite steel tubeconfined concrete column under low cyclic loading because the force and deformation ofthe joints under seismic load plays an important role in earthquake. The purpose of thisthesis is discuss the influences of each parameter on skeleton curve of the joints of thecomposite steel tube confined concrete column, which on the basis of reading a largenumber of domestic and foreign literature, and analyze the failure modes of the joints, thenfind out the regular influence of each parameter.This paper uses the finite element software ABAQUS to simulate three of reinforcedconcrete beam composite steel tube confined concrete column joints which have differentof the reinforcement ratio in beam and the diameter of steel tube at first, and comparingwith test result. The analysis results show that the curve, failure modes and the developingof the cracks under the eccentricity compressive load and level earthquake, through theABAQUS software to establish the finite element model. The indicate finite elementanalysis is effective. Then on the basis of the finite element model of the joint, discuss theinfluences to the skeleton curve of the reinforcement ratio in beam, encased effectcoefficient of the steel tube, the location factor, the hoops spacing, concrete strength, andso on. The calculation results show that the existence of the tubes to improve the bearingcapacity of the joints, the influence of the reinforcement ratio in beam, encased effectcoefficient of the steel tube, the location factor and the axial load level is bigger and theinfluence of the strength of concretes and the hoops spacing is smaller. Finally study theperformance of the failure modes of the joints of the composite steel tube confinedconcrete column. The calculation results show that the influence of the reinforcement ratio in beam, encased effect coefficient of the steel tube, the location factor, the hoops spacing,contain tube rate is bigger and the influence of the strength of concretes and the axial loadlevel is smaller.