Abstract:
The influence of boundary conditions in the numerical calculation of the stress-strain construction of anisogrid structures is considered in the paper. The numerical calculation is based on the application of the finite element method in the variational formulation. The paper presents variants of the fulfillment of boundary conditions on the lower and upper edges of the construction. The schemes of fastening in the form of hinged closing and rigid fastening for the bottom edge of designs. The variants of specifying axial loading in the form of a distributed load and a “hard” node for the upper edge of the structures are considered. The article presents the kinematics of a “hard” node for lattice construction. As an example of the effect of fixing on calculations, a comparison of the number calculations and field experiment. The results show that the way to set the boundary conditions has a significant effect on the calculation results.
Keywords:boundary conditions; finite element method; discrete modelling; lattice shells.