Study On The Stress Performance And Design Of The Pull Screw Type Aluminum Alloy Formwork

With the implementation of national carbon emission reduction and carbon neutrality policies,aluminum alloy formwork,as a green material,has been widely used in building construction.However,problems such as slurry leakage and mold blasting have occurred frequently in the construction process,causing unnecessary economic losses to the project.The reason is that the understanding of the mechanical properties of aluminum alloy formwork is insufficient.In the scheme design,the calculation model and construction measures of the formwork cannot be fully understood.Because the standard formwork produced by various enterprises is different,the versatility of aluminum alloy formwork is not high.Aluminum alloy formwork is divided into two systems : the pull tab type and pull screw type.Both systems have the above problems,but compared with the pull plate system,the pull screw type aluminum alloy formwork has the characteristics of more convenient installation and adjustment,better concrete forming effect and wider market use.Therefore,this paper takes the pull-screw aluminum alloy formwork system as the research object,and uses the methods of theoretical calculation,numerical simulation and field measurement to study the mechanical performance of the pull-screw aluminum alloy formwork system.Based on the results of enterprise research,the original formwork is optimized to obtain a lightweight pull-screw aluminum alloy standard plate.The specific research contents are as follows :(1)The pull-screw aluminum alloy formwork produced and used by various enterprises was investigated,and the production and processing technology of the system formwork was sorted out.The size and specifications of the pull-screw aluminum alloy standard formwork of each enterprise were obtained.(2)The theoretical calculation and numerical simulation of the pull screw aluminum alloy formwork system were carried out.Combined with the engineering example,the formwork system was theoretically checked by theoretical calculation.The numerical model of the pullscrew aluminum alloy formwork system is established,and the simulation results directly reflect the deformation of the formwork under the lateral pressure of concrete.(3)The field measurement of the pull screw aluminum alloy formwork system was carried out.Through the deformation monitoring of each part of the template under different working conditions,the deformation of the measuring points at different positions of the template under the actual load is obtained.The field measured values are compared with the theoretical calculation values and numerical simulation results.The comparison results show that the stress value and displacement value obtained by the field measurement of the panel and the transverse rib are compared with the theoretical calculation results.The difference is about 20 % ～ 30 %,indicating that the design is more conservative and there is a large optimization space in the material consumption.The deformation trend of the numerical simulation template under the action of concrete lateral pressure is consistent with the deformation trend of the field measured template,and the numerical error is within 10 %,which proves the correctness of using the numerical simulation software to establish the template model of the system.(4)Through the comparative analysis of theoretical calculation,numerical simulation and field measurement,and based on the results of enterprise research,combined with the numerical simulation software ABAQUS,the original double-pulling screw type aluminum alloy template was optimized,and a lightweight double-pulling screw type aluminum alloy standard plate was designed.The optimized template saves 11.25 % of the original template material.