Simulation Analysis Of Integral Lifting Construction Of Double Span Hangar Roof Grid

For nearly three decades,China’s large span space grid structure development speed is very fast,various types of buildings across the country can be seen on the figure of space truss structure.At the same time,more and more safety accidents occur in the process of installation and construction of the grid frame,such as the collapse of the grid frame.In order to reduce the occurrence of accidents,people not only put forward higher requirements on the construction process and construction technology,but also apply the finite element analysis technology to the construction process.Before the formal installation and construction of the grid frame,the simulation analysis of the installation and construction process of the grid frame has the role of guiding the installation and construction of the grid frame.Before the formal installation and construction of the grid frame,the simulation analysis of the installation and construction process of the grid frame plays a role in guiding the installation and construction of the grid frame,which can understand the possible problems in the installation and construction of the grid frame in advance,and solve them before the installation and construction of the grid frame.In this paper,the overall lifting project of double span hangar roof truss in the completion center of Jiangxi Production and Test Flight Center of Comac is taken as the research object.Finite element analysis method is used to simulate and optimize the overall lifting construction process of the grid truss,and the lifting bracket is checked.As there is still room for optimization,the position of the lifting point is optimized.At the same time,the whole lifting construction process of the paint hangar of Jiangxi Production and Test Flight Center of Comac was simulated and analyzed,and the lifting bracket was simulated and the position of lifting point was optimized.The main conclusions are as follows:(1)The maximum deformation and the maximum stress ratio of the truss members in the lifting process of the finished central roof grid meet the requirements of the national code,and there is no instability risk,but there are 25 rods that do not meet the requirements of the slenderness ratio code.After replacing these 25 rods with those with larger section size,the slenderness ratio of the truss rods meets the specification requirements.(2)There is a huge gap between the actual installation state and the design state of the completed central roof grid.In the design state,the deformation degree of the grid structure is small,the slenderness ratio of the rods meets the requirements of the code,and the stress ratio of the rods is less than 0.5.However,during the actual installation of the grid structure,there are some rods with stress ratio greater than 0.5and those that do not meet the standard of the slenderness ratio.The deformation of the grid after the installation in place is much more serious than that of the design state.(3)When the lifting bracket of the completed central roof is lifted,the deformation degree is relatively small,the stress ratio is also in line with the national norms,and there is no instability risk,which can ensure the smooth progress of the overall lifting construction of the grid.(4)There is an optimized space for the lifting point position of the central roof grid frame.Three new lifting point layout schemes are designed.After simulation analysis,it is known that the optimal lifting point scheme is that the A3 and A8 lifting points are placed near the 10 m supporting structure in front of the original lifting point position,and the A4 and A7 lifting points are placed near the 20 m supporting structure in front of the original lifting point position.(5)The maximum deformation and the maximum stress ratio of the grid frame in the lifting process of the paint hangar roof meet the requirements of the national code,and there is no instability risk,but there are 29 rods that do not meet the requirements of the slenderness ratio code.After replacing the 29 bars with those with larger section size,the slenderness ratio of the mesh bars meets the specification requirements.(6)The simulation analysis is carried out on three kinds of lifting supports of the painting hangar roof grid lifting project.The results show that the deformation degree and stress of the three kinds of lifting supports in the process of grid lifting meet the requirements of the national code,and there is no instability risk,which can ensure the smooth progress of the grid lifting.(7)There is an optimization space for the lifting position of the hanging point of the paint hangar roof grid frame.A total of three new lifting point layout schemes are designed.After simulation analysis,it is known that the optimal lifting point layout scheme is the one in which the lifting points of D04 and D05 are arranged at 4.5m nodes in front of the original lifting point position.