STUDY OF INITIAL FORCES IN A DOUBLE-LAYER METAL DOME DUE TO ELIMINATION OF ANNULAR IMPERFECTIONS OF INSTALLATION

Abstract

When constructing large-span metal domes different methods of installation are used, which depend on geometry schemes of the frames and their construction solution. The frames of such domes consist of a lot of structures. During assembling large number of structures with different spatial orientation are joined together. Little differences of structures lead to distortion of their real geometric form compared to the design form. A computer analysis of the values of the initial forces due to force elimination of assembly errors of double-layer framed metal dome has been performed. The position errors of nodes of planar meridional ribs were considered in the annular directions at installation of the dome frame with temporary central support. The initial forces due to the connection of already assembled sectors of the dome with annular elements at different stages of the construction of the frame of the dome are investigated. For this purpose concentrated forces were applied to the nodes of the sectors to eliminate relative deviations of the connected ribs, and initial internal forces in the bars were registered. The values of the initial forces in the bars were compared to the values of the initial forces due to the dead load and design load. The results of the investigation are presented in the form of figures, schemes, diagrams, and tables. The conclusions are made on the influence of the initial forces on the stress-strain state of the dome frame.