Finite Element Analysis Of The Construction Process Of Large Roof

With the development of our national economy and the intensification of infrastructure construction, the application of large space grid structures are unceasingly increasing, however, its complex structure spatial layout and the massive project size bring us tougher challenges for site operation, therefore, the safety and rationality of construction is even more important than usual.This paper take the roof gird of one station as a practical example and the construction steps of its partitioning assembly methods the research object, using the ANSYS finite element method, simulate the lifting、perch of the Lifting elements and uninstall process after the completion of the total gird assembly during the construction.In the assembly process of lifting elements, by setting hinged join to constraint to reflect the role of lifting rope, while the simulation of Hoisting in place,means constrain the nodes which are set up a temporary support and apply the gravity load to the structure,then get the axial stress of member bars and distortion of nodes by calculating, and the results all satisfy requirements of technical Specification.The stability checking in the member hosting process:accomplish the Stability checking through getting the axial stress of the model computed result, and comparing the critical stress, which are got by member section, length another geometric parameter, and the results also satisfy the stability requirements.The uninstall process of gird, to remove the constraint of the temporary support to the structure, the simulation of this process, is to select36asymmetrical nodes of bottom chord of gird, constrain the three direction freedom of motion of these node,then hundred-percent release the freedom of constrained nodes in batches, observe the change rule of the displacement deformation,then get the displacement deformation of the36nodes In each uninstall step,through the comparison,prove the setting of reasonable temporary support points has an important significance for the safety of the unloading process, at the same time, The final structure deflection meet structure the requirement of the specifications.Through the above analysis and research,Clearly describe the influence of the each construction steps to the structure,give some suggestions,it provides a good revelation role for the future construction steps of project and the selection of best construction method, and provide a reference to the future study of computer simulation of the construction process.