Collaborative Research: Performance-Based Framework for Wind-Excited Multi-Story Buildings

目前单纯依赖于满足标准中规定的要求的规范性设计理念正在转向基于性能的设计(PBD)方法，以实现合理地满足社会对安全建筑环境的需求的设计。广泛的研究促进了PBD在地震工程中的成功采用，但对于风力工程和风灾来说就不是这样了。风对建筑物的作用与地震荷载不同。风荷载持续时间长，与地震荷载相比，风荷载对人的舒适度更重要。因此，在设计建筑系统以抵御强风事件时，有必要开发一个包含PBD概念的框架。这将为新建筑的设计者和现有建筑的翻新者提供一种手段，不仅可以合理地评估结构在风中的性能，还可以用决策者可以理解的语言传达他们的结果。广泛使用PBD过程的一个主要障碍是它们的不确定性，这使得传统上涉及到设计过程的迭代不切实际。这些不确定性可以通过开发特定的优化方案来有效地解决，这些方案可以处理现实世界应用的规模和多样性。该项目将为多层风激励建筑开发一个PBD框架，以最佳地减轻结构和非结构破坏。该方法将明确说明自然灾害结构性反应评估各方面不可避免的不确定性。这一目标将通过定义有效的风力建筑性能模型来实现，该模型将根据后果和易损性功能合理地评估损害和损失。为了推动建筑物的性能，将根据一系列风事件(例如天气风和飓风)的适当强度测量来定义特定工地的风灾模型。通过确定合适的空气动力学模型，将定义相互作用参数，以驱动以模拟为中心的基于塑性定理的框架，该框架不仅产生风中性能的输入工程要求参数，而且还提供结构系统屈服后行为的完整描述。为了使系统最优地满足性能目标，风能边界条件优化问题将被描述为一个概率优化问题。通过开发一种能够有效地处理以高维设计变量向量的系统级概率约束和/或目标函数为特征的问题的通用解决方案策略，将定义一种集成的PBD和优化方法，有望彻底改变当前的风能工程实践。

The current prescriptive design philosophy that relies simply on meeting requirements stipulated in standards is shifting towards a performance-based design (PBD) approach for achieving designs that rationally meet society's need for a safe built environment. Extensive research has facilitated the successful adoption of PBD in earthquake engineering, but the same cannot be said for wind engineering and wind hazard. Wind acts differently on buildings than the earthquake loading. Wind loading is of long duration and performance is more critical for human comfort than for the earthquake loading. Therefore, the need exists to pursue development of a framework that embraces the concepts of PBD during the design of building systems to resist severe wind events. This would offer designers of new buildings and retrofitters of existing buildings a means not only to rationally assess the performance of structures under winds, but also to communicate their results in a language that decision-makers can understand. A major hurdle to the widespread use of PBD procedures is their uncertain nature, which makes the iterations traditionally involved in a design process impractical. The uncertainties can be effectively addressed by the development of specific optimization schemes that can handle the size and diversity of real world applications. This project will develop a PBD framework for multi-story wind excited buildings in order to optimally mitigate structural and non-structural damage. The methodology will explicitly account for the inevitable uncertainty that characterizes all aspects of structural response estimation to natural hazards. This goal will be achieved through the definition of an effective wind building performance model that will rationally assess damage and loss in terms of consequence and fragility functions. To drive the building performance, site-specific wind hazard models will be defined in terms of appropriate intensity measures for a range of wind events, e.g. synoptic winds and hurricanes. By identifying suitable aerodynamic models, interaction parameters will be defined for driving a simulation-centered plastic theorem-based framework that not only yields input engineering demand parameters for performance in wind, but also provides a full portrait of the post-yield behavior of the structural system. In order to achieve systems that optimally satisfy the performance objectives, the wind PBD problem will be formulated as a probabilistic optimization problem. By developing a general solution strategy capable of efficiently handling problems characterized by system-level probabilistic constraints and/or objective functions in terms of high-dimensional design variable vectors, an integrated PBD and optimization methodology will be defined that has the promise to revolutionize current wind engineering practices.