Advanced Characterization of Inelastic Performance of Tall Buildings to Wind for Performance-Based Design

本研究计画将发展有效的分析架构，以评估高层建筑物在风荷载作用下的非弹性反应，并可用于支持基于性能的风设计。目前的建筑设计风荷载没有明确允许结构的行为超过线弹性极限，即使在极限风荷载。这种线性设计方法可能会限制使用更具创新性的高层建筑系统，提高性能，安全性和经济性。关于高层建筑物在风荷载作用下的非线性非弹性性能，在建筑物抵抗极端风荷载的实际能力和可靠性方面的信息很少。该项目将解决关键的研究需求，并缩小知识差距，实现PBWD的高层建筑与非弹性行为的考虑。项目成果将用于丰富研究生的教学和培训。该奖项将有助于国家科学基金会（NSF）在国家减少风暴影响计划（NWIRP）中的作用。项目数据将在NSF支持的自然灾害工程研究基础设施（NHERI）数据库（https：//www.example.com）中存档并公开提供。www.DesignSafe-ci.org在此项目下开发的计算工具将与NSF支持的NHERI计算建模和仿真中心的软件框架相结合。该研究项目有三个具体目标。首先，该项目将使用高保真、三维、非线性有限元建筑模型，在真实的三维动态风荷载下，对不同高度和建筑结构系统的高层建筑的非弹性性能进行表征。响应分析将对非弹性建筑响应的独特特性提供新的见解;双轴和三轴响应相互作用; P-Delta的影响，强度退化和刚度退化;以及质量和刚度偏心率的影响。 其次，该项目将开发降阶非线性建筑模型和分析框架，用于评估概率非弹性响应。单轴、双轴和三轴荷载下的模态推覆分析将被实施，以生成滞后广义力模型，并开发具有计算效率的降阶非线性建筑模型。将通过全面的反应历史分析和与高保真非线性有限元模型的预测进行比较，验证降阶建筑模型的准确性。统计线性化方法将进一步促进非弹性响应统计的预测。第三，该项目将建立评估非弹性性能建筑物可靠性的框架。将模拟和评估非弹性极限状态建筑物响应评估中涉及的各种不确定性。在不同的平均风速和风向的多个需求相关联的脆弱性函数将被评估，并将进一步集成的风速和风向的联合概率分布的建筑系统的可靠性评估。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This research project will develop efficient analysis frameworks for assessing the inelastic response of tall buildings under wind loads, which can be used to support performance-based wind design (PBWD). Current building design for wind loads does not explicitly permit structures to behave beyond the linear elastic limit, even under ultimate wind loads. This linear design approach may limit the use of more innovative tall building systems with improved performance, safety, and economy. There is very little information concerning the nonlinear inelastic performance of tall buildings to wind in terms of the actual capacity and reliability of buildings against extreme wind loads. This project will address the critical research needs and close the knowledge gap for achieving PBWD of tall buildings with consideration of inelastic behavior. The project outcomes will be used to enrich instruction and training of graduate students. This award will contribute to the National Science Foundation (NSF) role in the National Windstorm Impact Reduction Program (NWIRP). Project data will be archived and made publicly available in the NSF-supported Natural Hazards Engineering Research Infrastructure (NHERI) Data Depot (https://www.DesignSafe-ci.org). Computational tools developed under this project will be integrated with software framework of the NSF-supported NHERI Computational Modeling and Simulation Center. This research project has three specific objectives. First, the project will characterize the inelastic performance of tall buildings using high-fidelity, three-dimensional, nonlinear finite element building models with different heights and building structural systems under realistic three-dimensional dynamic wind loads. The response analysis will shed new insights on the unique characteristics of inelastic building response; biaxial and triaxial response interactions; influence of P-Delta, strength deterioration, and stiffness degradation; and influence of eccentricities in mass and rigidity. Second, the project will develop reduced-order nonlinear building models and analysis frameworks for assessing probabilistic inelastic response. Modal push-over analysis under uniaxial, biaxial, and triaxial loads will be implemented to generate hysteretic generalized force models and to develop reduced-order nonlinear building models with computational efficiency. The accuracy of reduced-order building models will be validated through comprehensive response history analysis and comparison with the predictions from the high-fidelity nonlinear finite element models. Statistical linearization approaches will be developed to further facilitate the predictions of inelastic response statistics. Third, the project will establish frameworks for assessing the reliability of buildings with inelastic performance. Various uncertainties involved in the assessment of inelastic limit state building responses will be modelled and assessed. The fragility functions associated with multiple demands at different mean wind speeds and directions will be evaluated, and will be further integrated with the joint probability distribution of wind speed and direction for evaluation of building system reliability. The directionality effect of wind climate and aerodynamics on inelastic building performance will be evaluated for better building design to wind.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.