Effectiveness of roof stiffening bars for upgrading lateral torsional buckling capacity of arches composed of H-sections

<p>The present study discusses the effectiveness of roof stiffening bars for enhancing buckling strength of an arch subjected to uniform and non-uniform loads, followed by a proposal for an evaluation method of buckling strength. The study assumes that the arch is composed of H-600x200x9x16 steel members. A new FEM line element is introduced to include the lateral torsional effects of the H-sections on buckling. The analyzed arch is categorized into four cases, each with different lateral stiffening positions along the arch length: upper flange and/or lower flange of the H-sections. Based on the analysis results, a buckling strength evaluation method is proposed, enhancing the design flexibility of spatial structures. The necessity of the new FEM line element for compound buckling in lateral torsional buckling analysis is confirmed. Additionally, the practicality of an approximate-beam element for compound buckling is also validated as an alternative method to the new FEM line element in lateral torsional buckling analysis.</p>