Taban İzolasyonu Üzerine Bir İnceleme

Öz

Binaların taban izolasyonunda kullanılan elastomer yatağın analizinde zayıf kayma rijitliğinin etkisi çok önemlidir. Özellikle, burkulma yükü düşük olup P-∆ etkisi kayma deformasyonlarının ihmal edildiği standart kolonlara nazaran önemlidir. Bu makalede, elastomerik izolasyon yatakların P-∆ etkisini işlemek için hem kayma hem de eğilme deformasyonlarını nazara alan basit bir mekanik model önerilmiştir. Model parametrelerinin yeterli seçimi ile basitleştirilmiş model hem statik hem de dinamik durumlarda gerçek modelle iyi uyum göstermektedir. Tabii kauçuktan mamul yataklar için deney sonuçları tatbik edildiğinde modelin, eksenel yükün dinamik direngenlik üzerine etkileri, sönümleme faktörü ve taşıyıcı yüksekliğinde azalması üzerine doğru sonuçlar verdiği bulunmuştur. Ayrıca, basitleştirilmiş model kullanılarak elastomerik yatakların ileri-burkulma çalışması da takdim edilmiştir.

Anahtar Kelimeler

• Taban izolasyonu, Elastomer yatak, Burkulma, Sonraki burkulma

AN INVESTIGATION OF BASE ISOLATION

Abstract

The effect of weak shear rigidity is important in the analysis of elastomeric bearings used for base isolation of buildings. In particular, the buckling load is low and the P-Δ effect is significant as compared to standard columns neglecting shear deformations. In this paper, a simple mechanical model accounting for both shear and flexural deformations is proposed to treat the P-Δ effect of elastomeric isolation bearings. With adequate choice of the model parameters, the simplified model agrees very well with an exact model in both static and dynamic cases. When applied to the experimental results for some natural rubber bearings, the model is found to describe with good accuracy the effects of axial load on the dynamic stiffness, the damping factor and the height reduction of bearings. A brief study of the post-buckling behaviour of elastomeric bearings using the simplified model is also presented.

Keywords

• Base Isolation, Elastomeric bearing, Buckling, Post-buckling

Kaynakça

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