Susceptibility of double-layer grid structures to progressive collapse

Çift tabakalı grid (ÇTG) yapıların yüksek derecede hiper statik olmaları nedeniyle, herhangi bir elemanını kaybetmeleri durumunda, kaybolan elemanın yükünün diğer elemanlara dağıtılmak suretiyle yeterli güvenlikte oldukları düşünülür. Yapılan deneysel ve parametrik çalışmalar, bu yaygın görüşün aksine, çöken kritik elemanın diğer elemanların zincirleme çöküşüne neden olabileceğini göstermiştir. Bu makalede çift tabakalı grid yapıların herhangi bir neden sonucu kritik elemanlarından birini kaybetmeleri durumunda, zincirleme çöküşe karşı hassasiyeti incelenmiştir. Değişik parametreler irdelenerek, ÇTG yapıların zincirleme çöküşüne karşı güvenliğini arttıran parametreler belirlenmiştir.

Çift tabakalı grid yapıların zincirleme çöküşe karşı hassasiyetleri

Because of their large internal degree of static indeterminacy, double-layer grid (DLG) structures are often assumed to have sufficient redundancy such that the loss of one member would cause force redistribution that can be accommodated by remaining structures. However, results of the several experimental and parametric studies show that progressive collapse could occur following the loss of one of several potentially critical members when the structures are subject to full service loading. This paper presents the susceptibility of DLG structures to progressive collapse when any one of a number of critical members has lost its load carrying capacity. By changing the parameters, it is aimed to determine which structure parameters improve the ability of the damaged structure to avoid complete failure.

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