The Research On The Complete Equivalent Initial Imperfection Of Formwork Supporting Frame With Pulley-clip Style

The formwork support frame is the system playing a temporary support roleinside the long-span or large clearance buildings while the concrete being cast-in-siteconstruction. However, it is the deficiency of research on this aspect that inducessome major security leaks. As the new scaffold developed independently in China,wheel buckle scaffolds(WBS) ingrate the merits of various steel scaffolding together,transforming the traditional friction-type connection into the bayonet joint withmethods of self-latching, which reduces the usage of spare parts. For this newformwork, following work has been accomplished through some experiment andanalytical calculation:(1) Considering the diversity of influential factors of WBS, complete equivalentinitial imperfection is put forward as a generic term of these factors;(2) New simplified calculation method is raised: that is the assumed equivalenthorizontal load is used to imitate the complete equivalent initial imperfection. Whileanalyzing the influences showed by complete equivalent initial imperfection on thestable carrying capacity of WBS-system, 1.3% to 2.1% of the ultimate bearingcapacity is brought to bear at the connections between horizontal stanchion andupright stanchion to stimulate the complete equivalent initial imperfectionapproximately so as to calculate and check the intensity and stability of highformwork supporting frame.(3) With the application of this new simplified calculation method in the thesis, alarge number of finite element calculation models are set up by the finite elementanalysis software- SAP2000, with the influential rules on stable carrying capacity ofWBS from the structural factors analyzed respectively, such as the aspects of theupright stanchion spacing, step length, the sweeping stanchion, the horizontal crossbrace, the vertical cross brace, the extended length of the top upright stanchion, etc.and also with the recommended values supplied.(4) In this paper the new simplified analytical method is proved to be reasonableby practical engineering examples---the wheel-buckle full hall formwork supportframe in the Changsha Riverside Cultural Park project (Concert Hall) and thefastener-style full hall formwork support frame of the cast-in-place box beam onTongping Expressway Bridge. Simultaneously, this thesis summarizes and emphasizes the security technology requirements of setting up the full hall formwork supportframe, ensuring the security and reliability of this project. Also, it provides somereference for the application of this wheel-buckle formwork support frame.