Structural Behavior Of Two-way Meridian Lattice Shell

Two-way meridian lattice shell is the single-layer lattice shells structure made of two groups of intercrossed full-length scalene angle steel along the direction of the sphere lattice lines. Each member is continuous curved bar which have the same curvature radius.The lattice shell structures have the advantages of saving material, convenient construction and are widely used in the practical project, especially in the head cover structure of petroleum and chemical storage tank. The modeling method, static behavior and stability behavior of two-way meridian lattice shell were researched in the paper.According to the composition character of two-way meridian lattice shell, the modeling method of this type of lattice shells and the concrete modeling steps were given by the finite element analysis method . In the paper, the problems of node coordinate, node number, automatic generation of the elements, direction node of the angle steel elements, lap of the angle steel members, imposing uniform load were mainly resolved.The static analysis of double-spans' two-way meridian lattice shell structures were researched, and distribution laws of axial force, moment, shear force and displacement of this type of lattice shell were concluded. The scalene angle steel joined by single edge was calculated according to the theory of axial compression in the code of steel structures, and the strength and stability of the lattice shell's member were checked out. The results showed that two-way meridian lattice shell had good mechanical behavior.The stability behavior of two-way meridian lattice shell was mainly studied in the paper. The nonlinear analysis for 15 kinds of two-way meridian lattice shell structures were carried out by using the variable parameters of structure span and interval angle of grid, and the effects of load distribution, initial geometric imperfection, lap mode of angle steel to the stable limit load of the structure were researched systematically.The conclusion and the law obtained in the paper provide good references for the design and analysis of the practical projects.