Collaborative Research: Transforming Building Structural Resilience through Innovation in Steel Diaphragms

合作研究：通过钢隔膜创新改变建筑结构的弹性

• 批准号: 1562490
• 负责人: Jerome Hajjar
• 金额: $ 18万
• 依托单位: Northeastern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1562490&HistoricalAwards=false
• 关键词: Collaborative; Research; Transforming; Building; Structural

America relies on a robust and resilient building stock to minimize harm to its citizens and damage to its economy due to extreme natural hazards such as earthquakes and hurricanes. In the past, structural engineers have focused their attention on creating stronger, more ductile, more reliable lateral-resistance systems that can be used within the walls of buildings to resist the extreme demands associated with these natural hazards. Comparatively little attention has been paid to the role of the floor systems of buildings in resisting these demands. The floor diaphragm acts as a critical element that distributes the demands developed in a building during an extreme event to the lateral-resistance systems and eventually to the building foundation. Steel deck, i.e., thin corrugated steel panels typically with concrete fill, forms one of the most commonly used diaphragm elements in multi-story steel buildings. This project has as its objectives: to develop fundamental understanding of steel deck diaphragms as structural systems integrated within the overall building performance, to develop improved strategies for accurate modeling of floor systems within three-dimensional building models, and to develop new solutions for steel deck diaphragms that enhance the overall structural resilience of buildings.Current lack of knowledge about floor diaphragm systems impedes a needed evolution for building design approaches from focusing on two-dimensional frame design to enabling creative solutions within three-dimensional building design. The utilization of the diaphragm as an energy dissipating system has not been harnessed nor optimized in buildings. This project will develop a series of building archetypes appropriate to steel deck diaphragms. An integrated experimental program will be conducted at the connection and diaphragm scale, including novel non-contact measurement schemes for revealing damage and deformations during testing, to bridge critical knowledge gaps that currently impede three-dimensional modeling and design of buildings. To explore new solutions for energy-dissipating diaphragms, this project will perform testing of structural fuses and develop prototypes for integrating these fuses into steel diaphragm systems. This project will also complete high fidelity material and geometric nonlinear finite element models to enable detailed investigations of the flow of forces in diaphragms and between the diaphragm and all connected components. A series of lower fidelity, reduced order models will be developed, appropriate for whole building analysis of selected building archetypes. Formal optimization of the role of the diaphragm in building response, including a novel two-level optimization scheme, will be performed. Taken together, these activities will provide a significant advancement in the state-of-the-art for design of building diaphragms. Through a comprehensive outreach effort with industry, the findings will be transferred to engineers and utilized to improve the structural resilience of the nation's buildings.

美国依靠强大而有弹性的建筑物库存来最大程度地减少对公民的伤害，并由于地震和飓风等极端自然危害而对其经济造成损害。过去，结构工程师将注意力集中在创造更强大，更具延展性，更可靠的横向抗性系统上，这些系统可在建筑物的墙壁内使用，以抵制与这些自然危害相关的极端需求。对建筑物的地板系统在抵制这些需求中的作用几乎没有关注。地板膜片是一个关键要素，它将极端事件期间建筑物中在建筑物中提出的需求分布给横向抗性系统，并最终分配给建筑物基础。钢甲板，即通常带有混凝土填充的薄瓦楞钢板，构成了多层钢制建筑中最常用的隔膜元素之一。该项目具有其目标：为整合整体建筑绩效中的结构系统发展基本了解，以制定改进的策略，以准确地建模三维建筑模型中的地板系统，并为钢甲板开发新的解决方案增强建筑物整体结构弹性的膜片。对地板隔膜系统的缺乏知识阻碍了建筑设计方法所需的进化，而不是专注于二维框架设计，而不是在三维建筑设计中启用创造性解决方案。在建筑物中尚未利用或优化，将膜片用作隔膜作为一种能量耗散系统的利用。该项目将开发一系列适合钢甲板隔膜的建筑原型。将在连接和隔膜量表上进行集成的实验程序，包括用于揭示测试过程中损害和变形的新型非接触式测量方案，以弥合当前阻碍三维建模和建筑物设计的关键知识差距。为了探索用于消耗能量隔膜的新解决方案，该项目将对结构保险丝进行测试，并开发原型，以将这些保险丝整合到钢膜片系统中。该项目还将完成高保真材料和几何非线性有限元模型，以详细研究隔膜中的力流以及隔膜和所有连接的组件之间的力流。将开发一系列较低的保真度，减少的订单模型，适合对选定的建筑原型进行整体建筑分析。将进行隔膜在建筑反应中的作用的形式优化，包括新型的两级优化方案。综上所述，这些活动将为建筑隔膜设计的最新设计提供重大进步。通过与行业的全面宣传活动，这些发现将转移给工程师，并用于改善国家建筑物的结构弹性。