Test Research And Finite Element Analysis On Hysteretic Behavior Of Linked Column Frame Structure

The linked column steel frame structure is a recoverable functional structure composed of a linked column system and a bending-resistant frame.When the earthquake is applied,the plastic damage can be concentrated on the link beam in the linked column system to form concentrated damage.After the earthquake,the function of the building can be quickly restored by simply replacing the link beam.In this paper,the experimental research and finite element analysis of the linked column steel frame structure are carried out,and the seismic behavior and failure mode of the structure are studied.The hysteretic behavior of the linked column steel frame structure with the web link beam is analyzed.The main work is as follows:(1)The specimen with a 1/3 scale of the linked column steel frame structure was fabricated,and the link beam was replaced twice in the test.In the first two tests,the specimen had no interlayer link beam,the third time.In the test,the inter-layer link beam was added,and a total of three hysteresis behavior tests were completed.The hysteretic behavior of the structure before and after the replacement of the link beam and the effect of the inter-layer energy dissipation coupling on the structural behavior are studied.The test results show that the seismic behavior of the linked column steel frame structure is better;the lateral stiffness of the structure is not significantly degraded before and after the replacement of the link beam;the plastic deformation of the structure is mainly concentrated on the link beam,which can be quickly achieved after the earthquake.The purpose of restoring the use;setting the inter-layer link beam can increase the bearing capacity,rigidity,energy consumption and other aspects of the structure.(2)The ABAQUS finite element software is used to establish the model of the linked column steel frame structure.The rationality of the modeling method was verified by comparing the finite element with the experiment.The finite element analysis method is used to simulate the hysteretic behavior of the frame structure with stiffeners and the energy dissipation of the long-hole webs.The analysis results show that when the beam with stiffeners is used,the shear yield type should be adopted,and the length e should be within(1.0~1.44)M_p/V_p.Increasing the grade of the main frame steel can significantly improve the bearing capacity of the structure.And reduce the extent of stiffness degradation.When the long-hole web is used to link beam,the increase in the thickness t_w of the link beam'web can increase the rigidity,bearing capacity and energy consumption of the structure.The smaller the aspect ratio?of column between holes to web,the better the structural behavior.Considering the stress concentration and the initial defects of the steel,it is recommended that?should be 1~1.2.The increase of the length L of the link beam of the long-hole web can improve the energy dissipation behavior of the structure.However,when the L is too long,the plasticity development is insufficient,and the material behavior cannot be fully exerted.It is preferable to take the main structure span of 0.16~0.22 times.Increasing the grade of the main frame steel still improves the bearing capacity and reduces the extent of stiffness degradation.