Study On Mechanical Properties Of Shear Panel Energy-Dissipation Components Using Low Yield Point Steel

Shear panel energy-dissipation components using low yield point steel have good energy-dissipation capacity,the seismic property of structures using shear panel energy-dissipation components can be effectively improved,and the disaster of the structure in the earthquake can be reduced.This type of component,which has been widely used in the engineering practice,has a greater energy dissipation capacity compared to its construction size and is inexpensive.The Specimen,which was pure steel shear plate,lacking flange plate and the restrained reinforced concrete plate.It easily occurred overall torsional buckling and local buckling on outside surface.In order to investigate the influences of out-of-plane imperfection on the energy-dissipation capacity of shear panel energy-dissipation components and solve the shortcomings about overall torsional buckling and local buckling on outside surface of low yield point shear plate components,some shear panel energy-dissipation components were designed for the low cycle loading test.The out-of-plane imperfection,the width of shear panel and the reinforced concrete constraint plates were the main parameters.On the other hand,a series of parameter analysis was made in order to investigate the influence of different parameters on bearing capacity and initial stiffness of shear panel components and the corresponding formulas for calculating the bearing capacity and stiffness were proposed based on the finite element analysis results.The main research contents are as follows:(1)To obtain stress-strain relationship,Young's modulus,yield strength,ultimate resisting tensile strength and elongation of low yield point steel,a quasi-static tensile test was done for low yield point steel LYP160.In addition,these initial parameters laid the foundation of finite elemental analysis of components.(2)In order to investigate the influences of out-of-plane imperfection on the energy-dissipation capacity of shear panel energy-dissipation components and obtain the hysteresis curve of the shear plate components,one traditional I-shape steel energy-dissipation components and three shear panel energy-dissipation components with out-of-plane imperfection were designed for the low cycle loading test.And components' Failure modes,Out-of-plane buckling deformations,hysteretic curves,skeleton curves,Energy-dissipation curves,Stiffness degradation curves,equivalent viscous damping coefficient,degradation coefficient of multiple-cycle bearing capacity were conducted comprehensive analysis.Test results showed that the out-of-plane imperfection had significant effects on the behavior of shear panel components,and the reinforced concrete restrained plates effectually improved the energy dissipation capacity of shear panel components.The global and local stability of shear panel components could be well enhanced by the flange plate and reinforced concrete constraint plates.(3)Based on ABAQUS software about finite elemental analysis,the above mentioned shear panel components were carried out finite elemental simulation and analysis.The hysteresis curves and the skeleton curves of the shear plate components were obtained by using the parameters of the test material.The results were compared with the test curves.At the same time,an optimal structure of the shear plate component which both had flange plate and reinforced concrete restraint plate was proposed,and it shows the agreement of hysteresis curves was not very good from the comparison of numerical simulation and experimental curves.The agreement of skeleton curve was relative well,especially for the ultimate loading capacity.The optimized shear plate components had a stable,sustained energy dissipation capability.(4)a series of parameter analysis was made in order to make a further studied on the hysteretic behavior of shear plate components with optimized construction and investigate the influence of different parameters on bearing capacity and initial stiffness of shear panel components,then the corresponding formulas for calculating the bearing capacity and stiffness were proposed based on the finite element analysis results.Test results showed that the initial imperfection on the outer surface,the reinforced concrete constraint plates,the size of flange plates,the material strength of the flange plates,and the thickness ratio of the webs would significantly affect the ultimate loading capacity and the initial stiffness of the shear panel components.The calculation formula of bearing capacity and initial stiffness was accurate and reliable.In this paper,the research on shear panel energy-dissipation components using low yield point steel is innovative,and its main innovations are as follows:(1)In engineering practice,the shear plate is a plain plate,so during the fabrication,transportation and installation,different initial imperfections often produce and thus exert great influence on the consumption ability of the shear plate components,especially exert greater influence on the stability of surface after yielding.Therefore,based on the experimental study,the paper exposes totally different initial conditions on the limited quantity of the specimen and gets the measured data about the stress performance of shear plate components on totally different initial conditions.(2)The traditional shear panel components with stiffeners can only restrain the local deformation of the shear plane panel components,while the restrained reinforced concrete slab could be used to prevent local buckling of the shear plane panel components,change the position of the buckling on outside surface,so the energy-dissipation capacity could be improved.The flange plate could be used to prevent overall instability of the shear plane panel components,Therefore,when the shear plane panel components is applied to the actual project,it should be with the flange slab and the restrained reinforced concrete slab at the same time.To reduce material waste and the amount of welding work,designers and engineers can design the flange at the end of the flange slab where bears a large pressure.(3)The calculation formula of the initial stiffness and ultimate bearing capacity of the shear plane panel components is obtained by using the theoretical calculation model and the finite element analysis data.The formula derivation is theoretically to be improved,but the calculated results are close to the actual results.It could provide a necessary reference to the designers.