Ali BAHÇIVAN, Vedat KARADAĞ

5043

Elastik zemin üzerindeki çubuk uygulamalarının serbest ve nonlineer titreşim analizi

Bu çalışmada, değişik mesnet koşullarında iki parametreli bütünüyle ve kısmi elastik zemin üzerinde üniform kalın çubuk elemanının serbest ve nonlineer titreşimlerinin analitik ve deneysel analizi yapılmıştır. Nonlineer analizde, sadece eğilme hareketi 6 serbestlik dereceli kalın çubuk elemanı serbest titreşimleri incelenmiştir. Çubukların titreşim analizi, değişik mesnet koşullarında boyuna uzama da hesaplara dahil edilerek incelenmiştir. Elastik zemin; Winkler zemin modülü ve kayma zemin modülü ile isimlendirdiğimiz iki modülle karakterize edilen sabit iki-parametreli model olarak temsil edilir. Kayma deformasyonu, zemin rijitlik parametreleri ve kısmi elastik zemin etkilerinin yanında, nonlineer eğilme, boyuna-eğilme girişimi ve büyük yer değişimlerinden kaynaklanan nonlineer etkiler incelenmiştir. Bu analizden elde edilen analitik ve deneysel sonuçlar arasında iyi bir uyumun olduğu da gözlenmiştir.

The analysis of free and nonlinear vibrations of beam applications on elastic foundation

In the present work, the analytical and experimental analysis of free and nonlinear vibrations of uniform thick beam element on two-parameter full and partial elastic foundation is made. In the nonlinear analysis, free vibrations of 6 degrees of freedom thick beam element are only investigated. The vibration analysis is also made considering axial displacement of the beam in different end conditions. The elastic foundation is idealized as a constant two-parameter model characterized by two moduli, i.e. the Winkler foundation modulus k and the shear foundation modulus kG. In the case kG=0, this model reduces to the Winkler model, i.e. the elastic foundation is idealized as a constant one-parameter model. The effects of shear deformation; foundation stiffness parameters and partial elastic foundation are examined. Nonlinear vibrations of the beam are calculated by considering all nonlinear effects. In the nonlinear vibration analysis, nonlinear bending, longitudinal-bending and large bending displacement effect are included to nonlinearity. In addition to these effects, nonlinear bending, longitudinal and large bending displacement are examined as nonlinear effects. The results obtained from the analytical and experimental studies are presented by showing in tables and graphs and their importance in design is discussed. The numerical results obtained from this analysis are compared with the exact or available solutions in the literature, whereever possible. The analytical and experimental results and comparisons show the effectiveness of the proposed method.
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İTÜ Dergisi Seri D: Mühendislik-Cover
  • ISSN: 1303-703X
  • Yayın Aralığı: 6
  • Yayıncı: İTÜ Rektörlüğü
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