Stability Research And Reliability Analysis Of Single-Layer Latticed Shell Structure

The purpose of this paper is stability research and reliability analysis of two common single-layer latticed shell structures: single-layer latticed spherical shell and single-layer latticed cylindrical shell.In this paper, Laoshan Velodrome, Tianjin science and technology hall and Tianjin West Railway Station taken for example, the effects of the initial defect, geometry and material nonlinearity, section forms on the overall stability of the two structures were studied, the degree of reliability based on the full-process analysis method in"Technical specification for space frame structures"and the Koite Theory in"Code for Spatial Latticed Structure"were compared.As a finite element analysis software, ABAQUS was used in the process of researching the stability of latticed shell structures and finally get the comparison result between the effects of the initial defect, geometry and material nonlinearity on ultimate capacity of the single-layer latticed spherical shell and single-layer latticed cylindrical shell. The research on the ultimate capacity and the total steel quantity under different conditions of section forms could offer the reference to similar structures. By using JC method, the paper calculated the structural reliability according to JCSS'recommendations.Through research, the paper draws the following conclusions:(1) Initial defect is one of the key factors of stability research on the single-layer latticed shell structures. But the influences on the structural stability from initial defect are different due to different structure types. It is related to the structure types and element arrangement principles.(2) In the dual non-linear stability analysis, the effects of material nonlinearity on the ultimate capacity of two kinds of shell structures are different. In practical engineering analyzing process, in order to get the ultimate bearing capacity of single-layer latticed shell structure which could be much close to the real, it is better to take into account the geometry and material nonlinearity. Through calculating how much the critical load factor in dual non-linear stability analysis descend from the critical load factor in geometry nonlinearity stability analysis and considering the actual situation, then decide whether the elastic-plastic buckling analysis is needed.(3)To the single-layer latticed spherical shell and single-layer latticed cylindrical shell, closed section could reach the equivalent ultimate capacity of the H beam, but save more steel.(4)The reliability based on the full-process analysis method in"Technical specification for space frame structures"is bigger than that based on the Koite Theory in"Code for Spatial Latticed Structure".