STABILITY ANALYSIS METHOD FOR LATTICE SHELLS ACCOUNTING FOR MEMBER BUCKLING

Member buckling may occur before the overall buckling of lattice shells, but the effect of member buckling is usually not taken into consideration in the current published literatures for the stability analysis. This paper investigates the effect of member buckling on the overall stability of lattice shells by introducing initial imperfections in members. The determination of element mesh, imperfection mode and imperfection amplitude is firstly discussed, and the internal force variation after member buckling and the influence of single member buckling on the overall stability of lattice shells are then investigated. The results indicate that, in the overall stability analysis of lattice shells, the effect of member buckling could be accounted for efficiently by introducing initial imperfections in members; for lattice shells that members buckle before overall buckling, it is necessary to take member imperfections into consideration, and the stability analysis without member buckling will overestimate the load-bearing capacity of the structure. Finally, a reasonable calculation procedure for the stability analysis of lattice shells is proposed, the comparison with experimental results shows that the proposed method is rational and efficient.