Reasearch On The Total Bearing Capacity Of Disk Lock Steel Tubular Type Of Super Thick Support System

Compared with other formwork support systems, disk lock steel tubular formwork support system has a lot of advantages, such as node connection is reliable, the space is in a good effect, convenient construction,low construction cost and so on.Because of these advantages, in recent years it has been widely used in all kinds of support structure. But for the application of ultra thick template support is less, the corresponding research is small. In this paper, based on the accelerated room of Chongqing tumor hospital template support system as the research object, using the previous research analysis on the supporting system of super thick plate.In this paper, the main research work and conclusions are as follows:① Introducing the domestic and foreign research present situation, and the calculation model, the calculation method of the fastener-style steel pipe formwork support system are summarize, because the acquaintance between the template support, and ultimately determine the calculation model of disk lock steel tubular formwork support system for semi-rigid steel frame structure.② A unit model of the frame was graded loading test, and then analyze the mechanical characteristics of the unit framework. By using SAP2000 simulation unit frame model, found that the joint stiffness has great effect on the bearing capacity; after comparison and analysis, to determine the stiffness value of node in 75 KN ?m/ rad, about 2 times greater than that of standard.③ Considering the influence of artificial factors, node stiffness value is 60 KN ?m/ rad, using ANSYS model analysis of the actual model of tumor hospital of linear and nonlinear bearing capacity. The consistent modal imperfection method was used to analyze the nonlinear bearing capacity, and found that the structure is very sensitive to initial geometric imperfections.④ The application of ANSYS analysis the factors, including tectonic factors(lift height, different settings of standing tube,diagonal brace, bottom reinforcing tube), loading area and direction, which affect the linear and nonlinear bearing capacity of the formwork support. Among the analysis of the bearing capacity, the consistent modal imperfection method was used to analyze the nonlinear bearing capacity(member nodes of the lowest order bucking mode considering the displacement of 0.1times).In the analysis of factors, found that diagonal brace has important effects on the bearing capacity of the template support, especially in a circle around the vertical diagonal brace can make the structure as a whole, thus greatly improve the bearing capacity of the structure.⑤ The bearing capacity of the template support was calculated by using different theoretical calculation formula, and then all kinds of theoretical calculation result compared with the results of finite element simulation; found that specification design value similar to the results of finite element simulation which considering the initial geometric imperfection, thus specification design value has certain rationality.⑥ Through on-site monitoring of the super thick template bracket of tumor hospital of Chongqing, internal axial force of bar size and trends were obtained during the concrete pouring. Found that the vibrating of concrete have less effect on the structure, but concentrated load has a bigger influence on the bearing capacity of the template support,so advice that don’t pile up concentrated load on it before concrete fully condense sclerosis.