Çift Donatılı Kirişlerin Doğrusal Olmayan Davranışına Göre Etkin Eğilme Rijitliğinin Belirlenmesinde Yeni Bir Yaklaşım

Abstract

Betonarme yapı elemanlarının etkin rijitliğinin güvenilir bir şekilde belirlenmesi, sismik bir etki altında binanın kapasitesinin güvenilir bir şekilde tahmin edilmesini sağladığından her zaman önemli bir araştırma konusu olmuştur. Boyuna donatı oranı ve beton basınç dayanımı gibi yük taşıyıcı elemanın tasarım parametreleri, her zaman sabit olmasa bile betonarme yapılarda çatlaklı bölümün etkin rijitliğini etkiler. Bu çalışmada, çift donatılı betonarme kiriş modellerinin çatlamış kesitlerinin rijitlik katsayısının belirlenmesi için tüm önemli tasarım parametrelerini kapsayan, güvenli ve daha hızlı, basit bir denklem önerilmektedir. Etkin rijitlik katsayısı için önerilen tahminler, sayısal sonuçlar temel alınarak çeşitli araştırmacılar ve standartlar tarafından verilen moment–eğrilik ilişkileri ile karşılaştırmalar yapılarak doğrulanmıştır. Kiriş kesitleri için önerilen denklem, makul ölçüde doğru ve tutarlı olan etkili rijitlik katsayısı değerlerini sağlamaktadır. Bu nedenle analitik çözümlerin sonuçları farklı araştırmacılara ve standartlara göre farklılık gösterebilir. Kesitlerin doğrusal olmayan davranışını ve kirişlerdeki etkin rijitliği etkileyen önemli bir parametrenin, beton dayanımı ve basınç donatı oranlarını içeren donatı oranındaki artış olduğu, analiz sonuçlarından elde edilmiştir.

Keywords

• Çift donatılı kiriş
• Etkin rijitlik
• Moment-eğrilik; Donatı çeliği
• Beton

A New Approach to Determine the Effective Flexural Stiffness of Doubly-Reinforced Beams According to Nonlinear Behavior

Abstract

Determining the effective stiffness of structural elements made of reinforced concrete with reliability has always been an important subject of research since it provides a reliable estimate of a building's capacity in the case of a seismic event. The load-bearing element's design parameters, such as the longitudinal reinforcement ratio and concrete compressive strength, influence the effective stiffness of the cracked section in reinforced concrete structures, even if it is not always constant. In this study, a secure and efficient approach covering all important design parameters is proposed to determine the stiffness coefficient of cracked sections of doubly-reinforced beam models. The proposed equation for the effective stiffness coefficient has been verified by comparisons with moment–curvature relationships and data provided by various researchers and standards, based on numerical results. For beam sections, the suggested equation provides values of the effective stiffness coefficient that are reasonably accurate and consistent. Therefore, it is possible that the results of analytical solutions may differ from each other according to different researchers and standards. Analysis results have shown that an important parameter influencing the nonlinear behavior of the sections and the effective stiffness in beams is the reinforcement ratio, which includes concrete strength and compression reinforcement ratios.

Keywords

• Doubly-reinforced beam
• Effective stiffness
• Moment-curvature
• Reinforcement
• Concrete

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