Burulmaya maruz kalan dairesel içi boş kesitlerin efektif en kesit tasarımı

Öz

Bu çalışma, burulmaya tabi dairesel boşluklu kesitlerin burulma rijitliğini artırırken ağırlıklarını azaltmaya yönelik olarak, dairesel boşluklu kesitlerin optimal etkili kesit boyutlarını belirlemek için analitik yöntemler geliştirmeye adanmıştır. Bu amaçla, içi boş dairesel kesit tasarımına referans teşkil edecek içi dolu dairesel bir kesitin yarıçapı belirlenmiş ve bu kesite dayalı olarak “Eşdeğer Kesit 1” ve “Eşdeğer Kesit 2” olmak üzere iki farklı içi boş dairesel kesit tasarım modeli geliştirilmiştir. Kesitler arasındaki eşdeğerlik, mekanik ve geometrik parametrelerin karşılaştırılması yoluyla sağlanmıştır. “Eşdeğer Kesit 1” modeli kullanılarak elde edilen tasarım sonuçları, bu modelin önemli ölçüde malzeme tasarrufu sağladığını ve bu malzeme tasarrufunun %70'e kadar çıkabildiğini ortaya koymuştur. Buna ek olarak, “Eşdeğer Kesit 2” modeli kullanılarak elde edilen sonuçlar, içi dolu dairesel kesit ile aynı ağırlığa sahip olarak tasarlanan içi boş dairesel kesitlerde maksimum kayma gerilmesinin %77, maksimum birim burulma açısının ise %90 azaldığını ve bu iyileşmelerin sonucunda da burulma rijitliğinin 9 kat arttığını göstermiştir. Burulma yüklemesine maruz kalan içi boş dairesel kesitlerin efektif en kesit boyutlarını belirlemeye yönelik türetilen analitik ifadeler, pratik mühendislik tasarımlarında kullanılabilirliklerini sağlamak amacıyla erişime sunulmuştur. Bu sonuçlar, optimize edilmiş kesit tasarımlarının burulma dayanımını artırırken malzeme kullanımını önemli ölçüde azalttığını ve mühendislik uygulamalarında yapısal verimliliği artırabileceğini ortaya koymuştur.

Anahtar Kelimeler

• Analitik yöntem
• İçi dolu dairesel kesit
• İçi boş dairesel kesit
• Burulma
• Efektif en kesit tasarım

Effective cross-section design of circular hollow sections subjected to torsion

Öz

This study has been devoted to developing analytical methods for determining the optimal effective cross-sectional dimensions of circular hollow sections subjected to torsion, with the aim of enhancing their torsional rigidity while reducing their weight. To this end, the radius of a solid circular section, which serves as a reference for the circular hollow section design, has been determined, and two different circular hollow section design models, namely “Equivalent Section 1” and “Equivalent Section 2,” have been developed based on this reference section. The equivalence between the sections has been ensured through the comparison of mechanical and geometric parameters. The design results obtained using the “Equivalent Section 1” model have demonstrated that this model achieves significant material savings, with the material savings reaching up to 70%. Furthermore, the results obtained using the “Equivalent Section 2” model have shown that, despite being designed with the same weight as the solid circular section, the circular hollow sections reduce the maximum shear stress by 77% and the maximum unit twist angle by 90%, resulting in a ninefold increase in torsional rigidity. The analytical expressions derived to determine the effective cross-sectional dimensions of circular hollow sections subjected to torsion have been made available to ensure their applicability in practical engineering designs. These findings have revealed that optimized cross-sectional designs can significantly enhance torsional resistance while reducing material use, thereby improving structural efficiency in engineering applications.

Anahtar Kelimeler

• Analytical method
• Circular solid section
• Circular hollow section
• Torsion
• Effective cross-section design

Kaynakça

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