| Steel-concrete combination beam frame structure can give full play to the characteristics of the material itself,compared to the traditional structure,has the advantages of good stability,good structure,good delay,but there is a large number of template projects and wet operations in the construction,leading to construction The speed is slow,which limits its further development.In order to solve the above problems,this paper proposes a new type of assembly peripheral laminated plate.The laminated plate is up to 70%,and it has sufficient stiffness,so it can save support in the construction and reduce the amount of wet work.This paper uses a combination of finite element and experimentation.By comparing the cast-in-place test piece,explore the seismic performance of the newly laminated floor combination beam frame nodes,the main research work and results are as follows:(1)The existing seismic test of steel structure end plate connection joint and the flexural capacity test of composite floor beam are analyzed by finite element method,and compared with the test,it is proved that the finite element simulation results are in good agreement with the test,and the modeling method of steel structure end plate connection joint and composite floor beam is obtained.(2)Combined with the verified modeling method,the edge joint model of composite floor composite beam steel frame is established.Through the comparative analysis of finite element results,the positive and negative bearing capacity of composite beam steel frame joints are48.01% and 16.49% higher than that of pure steel joints respectively,and the positive and negative initial stiffness are also greatly improved,indicating the strengthening effect of floor on frame joints.(3)Through the finite element analysis of the factors affecting the seismic performance of composite beam frame joints such as post cast strip material,composite surface width,composite surface post cast strip thickness and longitudinal reinforcement ratio.The results show that in a certain range,in addition to increasing the longitudinal reinforcement ratio,the positive and negative bearing capacity and initial stiffness of the joint are greatly improved,the other three parameters can only improve the positive bearing capacity and initial stiffness of the joint,and have little effect on the negative direction of the joint.(4)The seismic tests of two composite beam steel frame joints are carried out,and the seismic performance indexes such as joint failure mode,hysteretic curve,skeleton curve,bearing capacity and stiffness degradation curve are compared and analyzed.By using the finite element analysis method and comparing with the test results,the correctness of the joint model of composite floor composite beam steel frame is verified.It is found that the failure characteristics of composite specimens and cast-in-situ specimens are the same;Node corners are greater than0.03rad;The positive and negative bearing capacity of the composite specimen are 1.03 and 1.05 times of the cast-in-situ specimen respectively,and the initial elastic stiffness is 0.98 times of the cast-in-situ specimen;There is no significant difference in the degradation degree of bearing capacity and stiffness,ductility and energy dissipation capacity between the two specimens.The results show that the seismic performance of the joints in the composite floor composite beam steel frame is almost the same as that in the cast-in-situ floor composite beam steel frame.This article contains 107 figures,26 tables,70 references. |
