COMPREHENSIVE ANALYSIS OF A TRUSSES’ STABILITY WITH THE USE OF CORRECT DESIGN SCHEMES
Structural mechanics methods were used for investigation the stability of flat trusses with rigid nodes, taking into account the simultaneous longitudinal - transverse bending of all rods as a result of the equilibrium forms bifurcation. The values of the reduced buckling length coefficients for compressed elements are obtained and systematized with varying of main parameters of the design models, namely their geometry, lattice types, loading schemes and rods stiffness’ ratios. The calculated values of the reduced length coefficients are compared with the recommended by the current standards for the design of steel structures. In a number of cases, significant discrepancies were revealed both in the direction of excessive stability margin and with a dangerous underestimation of the critical load parameter. The results indicate the expediency of changing the regulatory concept of truss’s stability calculations, with the transition from element - by - element verification to the analysis of the structure’s overall stability.