Performance-Based Wind Engineering: Stochastic Approximation Algorithms for Wind-Induced Dynamics of Next-Generation Tall Buildings and Tower Structures

随着结构的复杂性和对建筑结构风致振动和损伤敏感性的不断提高，需要更准确、更有效的结构分析和结构响应估计方法。近年来，基于性能的风工程受到了人们的广泛关注，尤其是在建筑结构的研究方面。为了推进下一代超高层建筑和塔楼结构的分析，需要采用PBWE，即通过斜拉索将核心横向抗力体系与三维横向支撑体系相结合。拉索的三维布置可能达到前所未有的长度，使得这种类型的结构特别复杂。技术挑战之一是需要通过使用横向约束来连接拉索来形成索网，这种横向约束可以降低对风致振动的敏感性。这种独特的结构形式对未来的建筑施工特别有趣，但这种结构的风致动力还没有完全了解。了解高层结构在PBWE环境中的性能可以导致在给定的加载条件下更好的结构配置，与预期的安全水平和负担得起的成本保持一致，从而促进国家的福利和繁荣。研究成果将被纳入东北大学现有的风工程研究生课程和随机结构系统计算力学的新专题课程的教学模块中。项目数据将在国家科学基金会支持的自然灾害工程研究基础设施(NHERI)数据仓库(https://www.DesignSafe-ci.org).)中存档并公开提供本项目将在PBWE环境下研究高层建筑和高塔在湍动风荷载作用下的动力响应。将考虑对配置进行适当参数修改的基准建筑结构。这项研究将探索实现计算效率高、可伸缩的算法来研究高层结构的气动弹性。数值程序还将通过与国际学术机构和一家软件研究公司的专家合作，使用最先进的网格和云计算软件。随机数值求解器将被用来从初始随机特征值问题(由于结构的复杂性而具有部分未知或随机特性)提取固有频率和主振型，并随后在频域中计算风致动力响应。该项目将检查在气动载荷估计误差的影响下的结构性能，以及结构易损性曲线或表面的推导，这是在PBWE内估计结构失效或功能丧失所需的。研究成果将包括通过有效计算脆弱性(例如，位移和加速度)来确定表征结构安全运行的关键参数。参数研究还将揭示高层建筑和塔楼风致动力学的相关细节，这将有助于工程师设计这些系统。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The progressive increment of structural complexity and sensitivity to wind-induced vibration and damage in building structures leads to the need for more accurate and more efficient methods for structural analysis and estimation of structural response. Performance-based wind engineering (PBWE) has received considerable attention in recent years, especially for the study of building structures. PBWE is necessary to advance the analysis of the next-generation, super-tall buildings and tower structures, in which a core lateral resisting system is combined with a three-dimensional system of lateral bracings through stay-cables. The three-dimensional arrangement of the stays, which may reach unprecedented lengths, makes this type of structure particularly complex. One of the technological challenges is the need for forming a cable network by connecting the stays using transverse restrainers that can reduce sensitivity to wind-induced vibration. This unique structural configuration is particularly interesting for future building construction, but the wind-induced dynamics of this configuration is not fully understood. Understanding the performance of tall structures in the setting of PBWE can lead to better structural configurations for a given set of loading conditions, consistent with desired levels of safety and affordable cost, thus promoting national welfare and prosperity. Research results will be incorporated into teaching modules at Northeastern University for an existing graduate course in wind engineering and a new special topics course on the computational mechanics of random structural systems. 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). This project will examine the dynamic response of tall buildings and tall towers under the effect of turbulent wind loads within the setting of PBWE. A benchmark building structure with appropriate parametric modifications of configuration will be considered. The research will explore the implementation of computationally efficient, scalable algorithms for studying the aeroelasticity of tall structures. The numerical procedures will also use state-of-the-art software for grid and cloud computing through collaboration with experts from international academic institutions and a software research company. Stochastic numerical solvers will be employed to extract natural frequencies and principal vibration modes from an initial random eigenvalue problem (with partially unknown or random properties due to structural complexity), and subsequently evaluate the wind-induced dynamic response in the frequency domain. The project will examine the structural performance under the influence of estimation errors in the aerodynamic loads and the derivation of structural fragility curves or surfaces, needed for estimation of either structural failure or loss of functionality within PBWE. Research outcomes will include the identification of key parameters characterizing safe structural operations by efficient computation of fragility (e.g., displacements and accelerations). Parametric studies will also unfold relevant details on the wind-induced dynamics of tall buildings and towers, which will assist engineers in the design of these systems.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.