Stability Analysis And Scheme Optimization Of High Formwork Support For Fastener-Type Steel Pipe Scaffold

Based on the architectural characteristics of tall buildings,it is universal to choose the high formwork of fastener-type steel pipe scaffold as the temporary supporting structure in building construction.In recent years,the collapse of frame often occurs in the process of building construction,resulting in casualties and property losses.In view of the above problems,this paper takes the 1.5 million tons/year corn deep processing project-EPC general contracting project of crystalline sugar plant of Suihua Xiangyu Jingu Biochemical Technology Co.,Ltd.as an example,and launches research.In this paper,the original unreasonable high formwork scheme is redesigned and checked,and its stability is analyzed by finite element software,and the influencing factors of the stability of fastener-type steel pipe scaffold high formwork are analyzed.Based on the above research results,the scheme optimization is carried out corresponding to the high formwork design used in this project,which provides reference for similar high formwork scaffold design in the future.Specific research results are as follows:(1)In the construction site of the case project,the important components of scaffold are randomly selected and measured.Through sorting out the data and comparing the relevant specifications,it is found that the initial defects of materials are widespread in this project,and it is found that the initial defects should be considered when studying the stability of scaffold.Select a beam-slab element with reserved opening in this project,design the high formwork support scheme of fastener-type steel pipe scaffold and check calculation.Using Midas Civil finite element software,two frame models,the actual erection scheme and the design scheme in this paper,are constructed.(2)Nonlinear buckling is used to analyze the stability of the two schemes.Through analysis,the experience and practice of the construction unit in this project case are denied.At the same time,through the finite element analysis results,it is found that the structural weakness of this design scheme lies at the top of the upright pole near the entrance.According to the fastener-type steel pipe scaffold high formwork frame used in this project,through constructing multiple groups of finite element models,the influence of initial material defects on the stability of the frame is analyzed,and it is found that the initial defect of steel pipe wall thickness has more obvious influence on the stability of the frame than the diameter of steel pipe.At the same time,the influences of vertical and vertical spacing,scissors brace arrangement,sweeping rod height,horizontal rod step distance and other factors on the stability of high formwork support are analyzed.It is found that reducing the transverse and longitudinal spacing of upright members and the step distance of horizontal members can enhance the buckling capacity of the frame.It is advisable to set the height of sweeping rod to 200 mm.Horizontal scissors braces are most suitable at the top and bottom of the frame body.Setting vertical scissors brace is one of the most effective ways to strengthen the stability of frame.(3)According to the scaffold design scheme in this paper,combined with the above analysis conclusions,design three different optimization schemes,taking into account safety and economy,and optimize them.It is considered that the third optimization scheme is the best scheme,namely: 1)setting two vertical scissors braces at the reserved opening;2)setting two horizontal scissors braces at the top of the frame and one horizontal scissors brace at the bottom;3)appropriately increasing the distance between upright poles.