Study On The Mechanical Property And Optimal Design Of A New Type Of Mild Steel Damper

All building structures rely on their own absorption of earthquake energy to reduce earthquake damage.The forces on the beams and columns of the building cannot be quickly consumed.Once the earthquake intensity exceeds a certain value,the structure will enter the elastic-plastic state,and in severe cases may cause component yield and damage.In the early stage,the way to change this situation was to increase the cross-section of beams,plates and columns,which was obviously an uneconomical and unreliable way.The emergence of energy dissipation and shock absorption devices solved this problem to some extent.At present,such devices mainly include metal energy dissipators,friction energy dissipators and viscous energy dissipators.Mild steel dampers are one kind of metal dampers.Because of their low cost and strong applicability,they are widely used in various engineering fields.In this paper,a new type of mild steel dampers is presented: Side arc type center-opening mild steel damper.At present,many scholars have studied the performance of mild steel dampers.The usual experimental method is to make multiple dampers for loading,and then compare the results to get the conclusion.Such a method usually consumes too much financial and material resources,which is an uneconomical method.With the development of finite element,ABAQUS software has gradually evolved into a common software for studying mechanical properties.In this paper,according to the hysteretic characteristics of mild steel dampers,which are excellent,easy to install and easy to replace after the earthquake,a mild steel dampers installed on the cross support of chevron are studied by using the finite element analysis software ABAQUS,so that it has a higher steel utilization rate and a smaller stress concentration phenomenon.First of all,the model selection of the proposed 8 kinds of dampers is optimized,the shape of the dampers web is adjusted,holes are made on the left and right sides of the web,the performance of the dampers after opening is obtained and analyzed,and the optimal shape is selected to optimize the design of hole size adjustment.Plane through the damper opening hole size and adjust the parameters and hole form of permutation and combination,further optimize the performance of damper,the design of 54 kinds of different forms of open hole permutation and combination,analysis the stress distribution in stress distribution damper web,hysteretic curve is obtained by calculation of the data,finally get the optimal damper model.The shape of the damper and the shape,size and arrangement of the hole have great influence on the performance of the damper.Therefore,the optimization of the size of the opening and the optimization of the permutation and combination form are the key points and innovations of this paper.Five kinds of openings of different shapes were designed when the web of the damper was opened with large holes.Holes with water caltrop usually result in excessive stress concentration of the dampers at the sharp positions of water caltrop,which easily leads to dampers’ failure,such as diamond and equilateral triangles and square holes.However,the stress distribution around the circular hole is relatively uniform,and the stress concentration is rarely obvious.However,the bearing capacity of the damper is generally low after large opening,so the size of the circular hole is adjusted to 10.The smaller circular opening can change the arrangement and combination of the holes more flexibly,and the bearing capacity of the damper can be changed by changing the position and arrangement of the small circular opening,so as to reduce the stress concentration of the damper.After many simulations,it can be known that the center of the web should not be opened when four small circular holes are opened at the four corners of the web of the damper,and the arrangement and combination of the openings of the web have a great influence on the bearing capacity and stress concentration of the damper.Based on 62 damper models designed in this paper,the final model of Side arc type center-opening mild steel damper.