Research On Optimization Design And Engineering Applications Of Low Yield Point Steel Bearing

The isolation technology is a method to effectively reduce the seismic loss of building structures.Compared with the traditional seismic technology,the isolation technology has obvious advantages,and the application prospects are huge.It has developed rapidly in recent years.However,the commonly used seismic isolation bearings have more or less problems: the horizontal stiffness of the sliding isolation bearing is small,which causes the horizontal displacement under the earthquake to be large;the rubber isolation bearings are mostly expensive.And the pollution caused by the lead core in the support has not been effectively solved.The mild steel has low yield strength and large deformation capacity.The damper made of mild steel has the characteristics of stable energy consumption and environmental protection.In this paper,a soft steel isolation energy-consuming bearing is designed by using the characteristics of mild steel,and the energy dissipation performance of the isolation is deeply studied.The main work is as follows:(1)Analyze the principle of the base isolation structure and the basic characteristics of the isolation bearing and combine the advantages of mild steel and ordinary steel to propose a reasonable structural form of the soft steel isolation energy-consuming support,and analyze its working principle and compare it with The advantages of the commonly used isolation bearings are currently used.(2)Using ABAQUS finite element software to shape the shear energy dissipation plates with different aspect ratios,the plastic distribution is more uniform under shear force,and the aspect ratio of shear energy dissipation plates is found to be optimal.The influence of the shape is small,and the optimal shape curve function formula of the shear energy dissipation plate is fitted.(3)Through the analysis of hysteretic behavior under the low-cycle reciprocating load of the shear energy-consuming plates before and after optimization,it is concluded that although the stiffness of the sheared energy-consuming plates is smaller than that of the optimized shear energy-consuming plates,However,the maximum equivalent plastic strain is significantly reduced to about 50% of the optimized shear energy dissipation plate,and the energy and energy consumption coefficient per unit volume of the shear energy dissipation plate are increased.(4)Applying the optimized shear energy dissipation board as energy-consuming device to the soft steel energy-absorbing support,analyzing the parameters affecting the performance of the support,and finding that the influence of the width-height ratio of the energy-consuming plate on the stiffness parameters of the support is better.The large,high-thickness ratio has a great influence on the energy consumption performance of the support,and the bearing axial compression ratio has little influence on the horizontal performance of the support.After analysis,the high energy dissipation plate in the soft steel isolation energy dissipation support is recommended.The thickness ratio should be less than 12.5.(5)Applying the soft steel energy-absorbing support to the multi-layer frame structure,using the Midas Gen finite element software to set the traditional seismic model without isolation bearing and the lead rubber isolation bearing and soft steel respectively.The seismic isolation model of the seismic isolation energy-supporting bearing is subjected to the elastoplastic time-history analysis under the action of 8 degree medium earthquake.The research shows that the soft steel energy-isolated energy-supporting bearing can play the effect similar to the lead-core rubber isolation bearing.Better requirements for energy isolation and small bearing deformation.