ÇARPMA YÜKÜ ALTINDAKİ RİJİT PLASTİK KİRİŞLERİN ANALİTİK OLARAK İNCELENMESİ

Kirişler, kullanım ömürleri boyunca dinamik bir yükleme türü olan çarpma yüklerine maruz kalabilirler. Bu çalışmada kirişlerin düşük hızlı çarpma yükü etkisi altındaki davranışları analitik olarak incelenmiştir. Basit ve ankastre mesnetli kirişler, rijit plastik davranış kabulü yapılarak dinamik yükler altında incelenmiştir. Göçme mekanizmasının ani olarak plastik mafsal oluşumuyla gerçekleştiği kabul edilmiş, enerji ve momentumun korunma ilkeleri dikkate alınarak dinamik yük altında kirişlerin limit analizi yapılmıştır. Darbe yükü altındaki rijit plastik kiriş davranışı, benzer yükleme koşulları altındaki elastik kiriş davranışıyla karşılaştırılmıştır.

Anahtar Kelimeler:

Rijit plastik kirişler, enerji ve momentumun korunumu, çarpma yükü, plastik mafsal

AN ANALYTICAL INVESTIGATION OF RIGID PLASTIC BEAMS UNDER IMPACT LOADING

Beams might be subjected to impact loading which is a particular type of dynamic loading during their service lives. In this study the behaviour of beams under low speed impact loading has been investigated analytically. Simply supported and fixed ended beams have been analyzed with the assumption of rigid plastic behaviour. The collapse mechanism has been assumed to emerge by the instant formation of plastic hinges, hence, a limit analysis has been performed under dynamic loading considering the conservation principles of energy and momentum. The behaviour of rigid plastic beams under impact loading has been compared to the behaviour of elastic beams under similar loading conditions.

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