Belirgin Düşey Yük Etkisindeki Betonarme Kirişlerin Çevrimsel Yükler Altındaki Davranışı Üzerine Deneysel Bir İnceleme

Bu çalışmada tersinir çevrimsel yükle zorlanan betonarme kirişlerin düşey işletme yükü etkisini içeren ve içermeyen yüklemeler altındaki davranışları deneysel olarak incelenmiştir. Bu incelemelerde düşey yük etkisinin kuvvet, çevrimsel yük etkisinin yer değiştirme kontrollü uygulandığı yükleme geçmişiyle elde edilen deneysel sonuçlar, artan genlikli çevrimsel yer değiştirme uygulanan kontrol numunelerinin deneysel sonuçlarıyla ve ayrıca Türk Deprem Yönetmeliği Hasar Sınırı Yaklaşımı kabulleriyle elde edilen analitik sonuçlarla karşılaştırılmalı olarak irdelenmiştir. Bu incelemelerde kiriş mesnet kesitlerinin boyutlandırılmasında belirgin düzeydeki işletme yükünün, aşırı zorlanan plastik mafsal kesimlerinin tek doğrultulu çevrimsel davranış sergilemesine ve yönetmelikteki Hasar Sınırı Yaklaşımıyla belirlenen dönme kapasitesinin oldukça üzerinde plastik dönme kapasitesine neden olduğu tespit edilmiştir. 

An Experimental Research on Hysteretic Behavior of RC Beams under Significant Gravity Loads

In this study, an experimental research to obtain the effects of significant gravity load on the hysteretic behaviors of RC beams is presented. To this purpose, an experimental program is carried out in which gravity loads are applied by force controlled test procedure whereas cyclic loads are applied by displacement controlled test procedure. It is found from the experimental results that significant gravity load is an effective parameter on plastic hinge mechanism. The experimental results of specimens with and without significant gravity load are compared to each other. Experimentally observed damage states, plastic hinge zones and deformation demands are also compared with the respective values proposed by Turkish Seismic Design Code. The results of the limited number of test specimens show that, the loading procedure with significant gravity load effect leads to the formation of non-reversing plastic hinge and analytical collapse limit given in Turkish Seismic Design Code remains very conservative.

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