Enhancing the design of connections for fire resiliency

火灾会导致包括钢材在内的所有材料的许多结构损坏。为了确保钢结构建筑的弹性，梁柱节点应能够承受火灾引起的荷载。为了更好地了解这些节点在火灾下的结构行为，最终目标是确保优化的防火，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软件LS-DYNA进行所有分析，因为LS-DYNA广泛应用于咨询行业的商业项目。首先进行传热学分析，然后进行循环载荷分析。传热分析将考虑不同的火灾场景，其中LS-DYNA中的子程序将被开发为显式动态求解器。有限元分析将考虑钢材的不同导热材料性能，以评估所检查的防火材料。有限元分析将重点对延性不同的三种不同连接进行建模(双角连接、单角连接和剪力连接)。数值结果将评估连接的不同被动防火系统，例如喷洒耐火材料。开发的有限元模型将考虑散热，并基于火灾场景后的应力和变形，将提出平衡安全性、经济性和美观性的最佳设计。最后，将开发一个框架来使用LS-DYNA连接和更新来自Revit的初始设计模型。分析结果旨在考虑降低钢结构施工成本的同时，提出安全设计建议。拟议的合作伙伴关系的目标是显著提高与建筑物在暴露的热荷载下的弹性钢连接的有效设计相关的知识状况，并通过考虑降低此类钢结构的建造成本来提出安全设计方法。

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.