Uç kısmında kütle taşıyan viskoelastik bağlantılı bir ankastre kirişin modal özellikleri üzerine bir araştırma

Abstract

Bu çalışmada, ucunda kütle taşıyan viskoelastik bağlantılı ankastre çubuğun bağlantı noktası rijitlik ve sönümünün modal özelliklerine etkisi detaylı olarak incelenmiştir. Yapılarda yüzey sönümü olarak kullanılan viskoelastik malzemeler, titreşim ve ses yalıtımları için etkili bir uygulama olmalarına rağmen, her zaman ve her koşulda uygulama imkânı bulamamaktadır. Bu durumlarda, bağlantılarda viskoelastik malzemeler kullanılması tercih edilen yöntemlerdendir. Viskoelastik bağlantı doğrusal ve dönme yönünde kompleks rijitliğe sahip yay elemanları kullanılarak modellenmiştir. Ele alınan problem basit çubuk teorisi çerçevesinde incelenmiş, Bernoulli-Euler çubuğuna ait diferansiyel denklem ve sınır şartlarından hareket edilmiştir. Ankastre çubuğun modal parametreleri çıkartılan karakteristik denklemin iteratif çözümüyle elde edilmiştir. Sayısal sonuçlar, viskoelastik bağlantının doğrusal ve dönme yönündeki özellikleri değiştirilerek doğal frekans ve modal sönüm oranları olarak incelenmiştir.

Keywords

• Viskoelastik bağlantı
• Ankastre kiriş
• Uç kütle
• Modal özellikler

An investigation on the modal properties of a viscoelastically connected cantilever beam carrying mass at its end

Abstract

In this study, the effects of the connection point stiffness and damping of a cantilever beams with a viscoelastic connection carrying a mass at its end on its modal properties were investigated in detail. Although viscoelastic materials used as surface damping in structures are effective for vibration and sound insulation, they cannot be applied at all times and under all conditions. In this case, the use of viscoelastic materials in connections is one of the preferred methods. The viscoelastic connection was modeled using spring elements with complex rigidity in linear and rotational directions. The problem considered was examined within the framework of simple beam theory and the differential equation and boundary conditions of the Bernoulli-Euler beam were used as starting points. The modal parameters of the cantilever beam were obtained by iteratively solving the extracted characteristic equation. The numerical results were examined as natural frequencies and modal damping ratios of the system by changing the linear and rotational properties of the viscoelastic connection.

Keywords

• Viscoelastic connection
• Cantilever beam
• End mass
• Modal properties

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