ОЦЕНКА НЕСУЩЕЙ СПОСОБНОСТИ СТАЛЬНОЙ БАЛКИ МЕТОДОМ КОНЕЧНЫХ ЭЛЕМЕНТОВ ПРИ СОВМЕСТНОМ ДЕЙСТВИИ ЛОКАЛЬНЫХ И СДВИГОВЫХ УСИЛИЙ

Abstract

Thin-web steel girders attract with their efficiency in bending work. For such girders, the issue of ensuring local stability becomes very relevant. Calculation formulas in most cases are complex and have a limited scope of application. While the calculations based on FE models make it possible to more universally consider all the specifics of the designed element. The article deals with the calculation of the stability of the web girder under the combination of patch and shear loading by finite element modelling. Numerical models have been created and a comparative analysis with experimental results has been carried out. A description of the principles for constructing FE models (mesh size, material model, etc.), which must be observed when assessing the resistance and behaviour of beams with thin web, is presented. Sensitivity analysis of the FE model to the input parameters revealed the most important parameters (yield strength of steel, web thickness), the uncertainty of which must be taken into account when creating FE models. The convergence of the results allows the use of the finite element method in the design of steel beams for a qualitative and quantitative assessment of the resistance. However, further development of unified principles for creating FE models and their verification on a larger amount of experimental data is required, as well as the determination of partial factors to take into account the variability and uncertainty of the results obtained, taking into account the regulated reliability parameters.