| Castellated beams, characterized by light weight, large flexural stiffness, high load-carrying capacity, and so on, have been widely used in the world. For welding castellated beams, web and flange often are wide and thin to make full use of strength and stiffness of material, however, too wide and thin make castellated beams are prone to unstability, and it seriously restricted the spread and exploitation of castellated beams. Therefore, the research on steady bearing capacity and the forecast of castellated beams is necessary.In this article, overall stability of castellated beams with different lengths, different expansion ratio, different hole shape, different holes number is analyzed with finite-element analysis software ANSYS.In this paper, finite element models are established. They include circular hole and hexagon hole castellated beams with expansion ratio being 1.4, 1.5 or 1.6 and two semi-ellipse. Also solid-wed menbers are created. And then, stability analysis for these models under distributed load or cross concentrated load is carried out.And steady bearing capacity and the corresponding midspan deflection are given.Through comparative analysis, several conclusions can be summarized as follows: Critical load of expanded castellated beams is higher 20% than the original solid-web beams. Critical load of expanded castellated beams is lower less 10% than the same solid-web beams. Expansion ratio is same,critical load is close between circular holes and hexagon hole castellated beams with the same expansion ratio, but the latter is higher.Finally, based on using artificial neural network exact algorithm, interpolation computing formulas are established.Beam length, expansion ratio(or hole-high), holes number of castellated beams are input and deflection and buckling load are output.Through compared the results of samples interpolation analysis and the results of finite element method, it is showed that the interpolation functions are feasible. The analysis method in this paper provides a new approach for design and research of castellated beams. |