Research On The Integral Stable Mechanical Behaviors Of Frame Scaffoldings With The Strengthened Arch Steel Tube

The reinforced tube door type scaffold is a new type of scaffold in recent years,because of its main frame is "door" type,reinforced tube into arch shape;it has the characteristics of small weight,simple process,convenient,cost saving,high efficiency and beautiful.Nevertheless,some enterprises benefit from developing new products and new forms at home and abroad,these new products are often not through scientific research and demonstration,product performance is not clear,a large part of the lack of scientific and theoretical basis for innovation.The research units developed by the scaffold,since the system,not common,variety and specifications,not only to the construction unit use and management has brought great difficulties,but also is not conducive to the promotion and application of new doors,but also to construction safety hazards.Due to the different geometric size,material specifications,and the stability of the new type of scaffold,the stability has been changed.In order to understand the mechanical properties of the scaffold and analyze the various factors that influence the bearing capacity and failure mode,the experimental study and a large number of finite-element analyses are carried out in this paper.The main research work is as follows:(1)Firstly,in order to demonstrate the necessity and feasibility of this research,this paper summarized the current situation and problems of the domestic and foreign research on the door type scaffold.(2)A total stability test was carried out for the five groups of three steps of the true type,and the failure mode,the mechanical properties of the mechanism were analyzed.(3)Using the large finite element analysis software ABAQUS,the whole mechanical analysis model was established,and the load deformation curves of the members were simulated,and the failure mode and the ultimate bearing capacity were analyzed.(4)Through a comparative study of the test results and finite element simulation results,the different settings of the wall connecting pieces,scaffold boards,cross bracing,horizontal stiffeners and other rod structure parts effecting on the overall mechanical properties of scaffold were investigated especially the ultimate bearing capacity and stability changes,and the correctness of the finite element model was also verified.(5)Based on the ABAQUS software,a large number of parameter analyses were carried out.The effects of various factors such as the wall thickness,the height of the door frame,the length of the rod,the rotation rigidity,the initial imperfection,the shear strength and the wind load were obtained.(6)Combining the experimental results and theoretical analysis,the application prospect of this new type of scaffold and the improvement method were put forward,and some reasonable suggestions were given for the future research and development.