Betonarme binaların deprem davranışlarının artımsal dinamik analiz yöntemiyle değerlendirilmesi

Abstract

Bu çalışmada, betonarme binaların sismik davranışı artımsal dinamik analiz yöntemi kullanılarak araştırılmıştır. Sayısal çalışma için betonarme çerçeve bir bina seçilmiştir. Seçilen bina için doğrusal olmayan statik itme (Pushover) analizi ve artımsal dinamik analizler yapılmıştır. Doğrusal olmayan dinamik analizler için seçilen dört deprem ivme kaydı Türk Deprem Yönetmeliğinde Z2 zemin sınıfına göre tanımlanan spektruma ölçeklendirilmiştir. Analizler sonucunda binanın kapasite eğrisi, maksimum tepkileri ve göreli kat ötelemeleri elde edilmiştir. Tepki değerleri kullanılarak binanın idealize edilmiş dinamik pushover eğrisi belirlenmiştir. Elde edilen sonuçlara göre seçilen binanın artımsal dinamik analizlerinin yapılmasının deprem davranışının daha doğru tespit edilebilmesi için uygun olacağı görülmüştür. Statik itme analizinden elde edilen göreli kat ötelemelerinin 0.4g’ye kadar olan yer hareketine sahip depremlerin dinamik analizlerinden elde edilen göreli kat ötelemelerinden daha büyük sonuçlar verdiği belirlenmiştir.

Keywords

• Artımsal dinamik analiz, Statik pushover analizi, Yayılı plastik mafsal.

Evaluation of seismic behavior of RC buildings using incremental dynamic analysis method

Abstract

In this study, seismic behavior of reinforced concrete buildings the pushover and incremental dynamic analysis method was investigated. For numerical application, 7 storeys and 4 bays reinforced concrete frame with high ductility was selected. The total height of the building is 23 meters. Height of the first story of the building is 5 m and the upper story heights are 3 m. First and last bays are 6 m, second and fourth bays are 5 m. It was assumed that, the building importance coefficient 1.0. For incremental dynamic analyses SeismoStruct program which can simulate the inelastic response of structural systems subjected to static and dynamic loads was used. The selected earthquake records were scaled according to the elastic design spectrum for Z2 soil class defined in Turkish Seismic Code (TSC). A numerical study was performed for a reinforced concrete frame building. Pushover analysis according to triangular load shapes and incremental dynamic analyses were performed for selected building. For the nonlinear analysis, four ground motion records were selected to ensure compatibility with the design spectrum defined in the Turkish Seismic Code. The maximum response, dynamic pushover curve, capacity curves, interstorey drifts of the selected building were obtained. Results were compared each other and good correlation was obtained between the dynamic analyses envelope and static pushover curves for the building. According to results; Displacement increases depend on the increasing of ground acceleration. Minimum displacements occur at 0.1g ground accelerations while maximum values occur at 0.5g ground accelerations for all earthquakes. The interstory drifts increases depend on increasing of peak ground accelerations. For upper stories the interstory drifts obtained from scaled Imperial Valley and Kobe earthquakes exceed interstory drifts of the triangular load shapes. But, at lower stories, interstory drifts obtained from these earthquakes are under the interstory drifts of the lateral static load shapes except Kocaeli and Loma Prieta earthquakes. According to the findings, the lateral static loading shows dynamic behaviour of the selected building until 0.5g ground accelerations and lower staories. To evaluate the accurate behaviour of reinforced concrete buildings, the dynamic pushover envelopes should be compared with static pushover curve.

Keywords

• Incremental dynamic analysis, pushover analysis, distributed plastic hinge.