直立锁缝屋面系统风致破坏全过程研究

直立锁缝屋面系统广泛应用于厂房、车站、体育场馆等大型建筑中,但由于自重轻、柔性大,在强风作用下很容易发生局部损伤及整体破坏,探讨这类屋面系统的风致破坏模式和失效机理,以便提出有效的抗风措施很有必要。本文进行了足尺试验并结合精细有限元方法,对直立锁缝屋面系统在风荷载作用下的变形发展,直到局部屈曲,再到最终破坏的全过程进行了试验和数值的对比研究,探讨了屋面板在风荷载逐渐增大过程中的位移状况及各阶段的破坏模式与抗风承载力。结果表明,屋面系统的破坏模式为支座与屋面板在锁缝处的脱扣破坏,该脱扣始于屋面板中部屈曲所引发的整体大变形,从而使得临近支座的拉力出现陡增,进而导致脱扣。本文的有限元方法不仅能够完整再现上述变形过程和破坏模式,还能较准确地预测其关键位移及抗风承载力的大小。

Wind-induced damage processes of standing seam metal roof systems

Standing seam metal roof systems are widely used in large-scale buildings such as factories, stations, and stadiums, while they are prone to have local and overall damages under strong wind due to the characteristics of lightweight and flexibility. It is crucial to study the wind-induced response and failure mechanism of standing seam metal roof systems, so as to improve their wind-resistance performance. Full-scale tests and numerical simulation were conducted to investigate the wind-induced response of standing seam metal roof systems, which includes the process of deformation, local buckling, and final failure. The displacement, failure modes, and ultimate bearing capacity of roof panel at different stages were studied under increasing wind loads. Results show that the failure mode of standing seam metal roof systems was the clip separation from seam. Local buckling was observed before the failure, which resulted in the global deformation of the roof panel. The clip force near the local buckling increased rapidly after the occurrence of the local buckling and caused the clip separation. The proposed finite element method can not only simulate the whole process of standing seam metal roof systems subjected to wind pressure but also predict failure modes and ultimate bearing capacity precisely.