Enhancing the design of connections for fire resiliency

火灾会导致包括钢在内的所有材料的结构损坏。为了保证钢结构建筑的弹性，梁柱连接应能够承受火灾引起的诱导载荷。为了更好地了解这些连接在火灾下的结构行为，最终目标是确保优化的防火性能，可以考虑有限元分析（FEA）。先进的有限元分析可以补充实验数据，因为全尺寸火灾试验昂贵且难以进行。目前的项目将使用有限元分析软件LS-DYNA进行所有分析，因为LS-DYNA在咨询行业的商业项目中广泛使用。首先进行传热分析，然后进行循环加载分析。传热分析将考虑不同的火灾情况，其中LS-DYNA中的子程序将发展为显式动态求解器。有限元分析将考虑钢的不同导热材料性能来评价所检测的防火材料。有限元分析将重点模拟三种不同的连接方式，它们的延性不同（双角、单角和剪切连接）。数值结果将评估不同的被动防火系统的连接，如喷涂耐火材料。开发的有限元模型将考虑散热，并基于火灾后的应力和变形，提出平衡安全与经济和美学规范的最佳设计。最后，将开发一个框架来连接和更新从Revit与LS-DYNA的初始设计模型。分析结果旨在为考虑降低钢结构造价的安全设计提供参考。拟议的合作伙伴关系的目标是在暴露于热负荷的情况下，显著提高与建筑物弹性钢连接有效设计相关的知识水平，并通过考虑降低此类钢结构的建造成本，提出安全的设计方法。

Fire can lead to many structural damages for all materials, including steel. To ensure resiliency in a steel building, beam-column connections should be able to withstand the induced loading due to fire. To better understand the structural behaviour of these connections under fire with the final objective to ensure an optimized fire protection, finite element analysis (FEA) can be considered. Advanced FEA can supplement experimental data since full scale fire tests are expensive and difficult to be conducted. The current project will use the FEA software LS-DYNA to perform all analyses, since LS-DYNA is widely used in commercial projects in the consulting industry. First, a heat transfer analysis will be done followed by the cyclic loading analysis. The heat transfer analysis will consider different fire scenarios where subroutines in LS-DYNA will be developed into the explicit dynamic solver. The FEA will consider different thermal conductivity material properties for the steel to evaluate the examined fire protective materials. The FEA will focus on modeling three different connections that will vary in ductility (double angle, single angle and shear tab). The numerical results will evaluate different passive fire protection systems of the connections, e.g., spray-applied fire-resistive materials. The developed FEA models will consider heat dissipation and, based on the developed stresses and deformations after the fire scenarios, an optimal design that balances safety with economic and aesthetic specifications will be proposed. Finally, a framework will be developed to connect and update the initial design models from Revit with LS-DYNA. The analysis results aim to propose safe design by considering the reduction of the construction cost of steel structures. The goal of the proposed partnership is to significantly advance the state of knowledge related to an effective design of resilient steel connections of buildings when exposed thermal loadings and propose a safe design approach by considering reduction of the construction cost of such steel structures.