Mechanical Performance Research And Engineering Application Of High-rise Residential Formwork Support

In recent years, with the rapid development of China’s urbanization, high-riseresidential has become an important means to solve the contradiction betweenpopulation and land through "vertical" growth. The cast-in-situ concrete structureincreases day by day, and formwork engineering also receives more and more attentiondue to the rise and popularity of high-rise residential.Engineering applications of frame formwork support has a great progress over thepast years, and the study about stability bearing-capacity has been carried out by someresearch institutions. But the accidents rate caused by formwork support collapse hasbeen high and the security problem has become the focus of public attention. A varietyof frames in construction market often lack the scientific research and demonstrationwhich makes the construction enterprises difficult in its use and management.Combined with the structural characteristics of high-rise residential, a new frameMF1225is designed which has the advantages such as high bearing-capacity, fastconstruction speed, good economic returns and so on. Especially in formwork setting ofthe high-rise residential standard-floor, improve the efficiency, shorten the constructionperiod and reduce the project cost on the premise of construction safety. In order topromote the development and application of frame formwork support, which isnecessary for the systematic test research and theoretical analysis.The main research contents of this paper are as follows:(1) The structural stability bearing-capacity, the failure mode and the influence ofledger and bottom reinforcing tube to the mechanical performance have been analyzedthrough experimental phenomenon and test results in the bearing-capacity study ofhigh-rise residential frame formwork support. The results show that: four frame unitshave a higher bearing-capacity, and out-plane buckling occurs when the frame isdestroyed. Ledger and bottom reinforcing tube enhance bearing-capacity to a certainextent.(2) The finite element analysis software ANSYS has been adopted to carry outanalysis on the bearing-capacity and its influencing factors by building the structuralmodel from the theoretical viewpoint. The theoretical analysis and the experimentalresults exhibit the same rules by contrast to verify the reliability of the test results.(3) According to the experimental study and finite element analysis results, put forward a simple bearing-capacity formula of MF1225with the correction of lengthcoefficient which is convenient for construction enterprise to use.(4) Based on the reliability theory, the structural reliability and sensitivity analysisconsidering the influence of material property, geometric parameter and load has beencarried out by ANSYS. The result has proved that the properties of formwork support isgreatly affected by elastic modulus and the thickness of reinforcing tube.(5) The application research on construction and technology of high-rise residentialframe formwork support perfects the standardization of the system and promotespopularation and application of MF1225formwork support.