Effects of edge support and reinforcement ratios on slab panel failure in fire
Effects of edge support and reinforcement ratios on slab panel failure in fire
复制标题
边缘支撑和配筋率对火灾中板面板破坏的影响
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
R. Plank
中科院分区：
文献类型：
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作者：
A. Abu;I. Burgess;R. Plank
结构防火工程朝着更经济有效的解决方案的进步，需要越来越多地使用基于性能的方法来设计多层复合建筑。这些方法考虑了结构的真实的行为，并提供了优化消防使用的经济解决方案。优化结构以使用拉伸膜作用需要在结构上使用板面板。这些都是垂直支撑的轻型加固复合地板系统，允许在高温下双轴弯曲。在实践中，通过保护面板的周边梁来实现垂直支撑，以在所需的耐火时间内实现不超过620°C的温度。Bailey-BRE设计方法，它包括拉伸膜作用，使用这些垂直支撑的面板，以建立复合板在火灾中的能力。板的面板电阻是由组合梁的剩余强度和大挠度增强板的电阻的组合。Bailey-BRE方法的简单计算意味着更高的配筋率可以改善性能。然而，在这里报告的建模工作中没有观察到成比例的增加。这种差异可能是由于板的几何形状、组成或支撑条件造成的。此外，由于暴露在火中，面板的“垂直”支撑可能会失去。这将反过来影响拉伸膜的能力，预先阻止地板系统的结构故障。本文介绍了钢筋和竖向支承对板破坏的影响的有限元研究结果。本研究探讨了不同程度的保护对张力膜作用机制发展的影响。它检查了这种机制的发展和失败，考虑到不同程度的边梁保护，并与贝利BRE方法和各种设计验收标准的预测进行比较。1名研究生，部门英国谢菲尔德大学土木与结构工程系教授，地址：英国谢菲尔德S1 3 JD电子邮件：cip04aka@sheffield.ac.uk 2 Professor，Dept.英国谢菲尔德大学土木与结构工程系教授电子邮件：ian. sheffield.ac.uk 3英国谢菲尔德大学建筑学院教授电子邮件：r. j. sheffield.ac.uk
The advancement in structural fire engineering towards more cost-effective solutions has necessitated the increasing use of performance-based approaches to the design of multistorey composite buildings. These methods consider the real behaviour of structures and provide economic solutions which optimise fire protection usage. Optimising structures to use tensile membrane action requires the structural use of slab panels. These are vertically supported lightly-reinforced composite floor systems, allowing biaxial bending at elevated temperatures. Vertical support is achieved, in practice, by protecting a panel’s perimeter beams to achieve temperatures of no more than 620°C at the required fire resistance time. The Bailey-BRE design method, which incorporates tensile membrane action, uses these vertically supported panels to establish composite slab capacities in fire. The slab panel resistance is determined by a combination of the residual composite beam strength and the large-deflection enhanced slab resistance. The simple calculations of the Bailey-BRE method imply improved performance with higher reinforcement ratios. However, proportional increases have not been observed in the modelling work reported here. The discrepancy may be due to the geometry, composition or support conditions of the slab panels. Also, with exposure to fire, a panel’s ‘vertical’ support can be lost. This will in turn affect the tensile membrane capacity, pre-empting a structural failure of the floor system. This paper presents the results of a finite element investigation into the effects of reinforcements and vertical support on slab panel failure. The study examines the effect of various degrees of protection on the development of the tensile membrane action mechanism. It examines the development and failure of this mechanism, considering various degrees of edge-beam protection, and makes comparisons with the predictions of the Bailey-BRE method and various design acceptance criteria. 1 Research Student, Dept. of Civil & Structural Engineering, University of Sheffield, Sheffield S1 3JD, UK Email: cip04aka@sheffield.ac.uk 2 Professor, Dept. of Civil & Structural Engineering, University of Sheffield, Sheffield S1 3JD, UK Email: ian.burgess@sheffield.ac.uk 3 Professor, School of Architectural Studies, University of Sheffield, Sheffield S10 2TN, UK Email: r.j.plank@sheffield.ac.uk