Overview

This research pioneered an automated cyber-physical aerodynamic shape optimization approach for the design of tall buildings. A building's shape is one of the earliest design decisions and has a decisive impact on the building's underlying structural system, performance under service and extreme loads, lifecycle costs, and architectural appeal. Since the influence of a building's shape on the wind loading is substantial yet difficult to predict, the research integrated: (i) the reliability of boundary layer wind tunnel (BLWT) testing, (ii) the efficiency of numerical optimization algorithms to explore the design space, and (iii) the flexibility of hybrid manufacturing to create candidate shapes on demand for immediate experimental evaluation. In the developed framework, an optimization algorithm determines which building shapes to explore next based on previous data. Scaled specimens are rapidly manufactured and immediately evaluated using BLWT testing. The new results are fed back into the optimization algorithm, and the process repeats. This creates a loop of iterative improvements in building shape to reduce wind loads.

The project began by focusing on advanced manufacturing strategies to enable high-throughput wind tunnel testing. A six-axis robot arm and turntable system were set up at the University of Florida’s (UF’s) Powell Laboratory. Algorithms were developed to transform the 3D computer building models into toolpaths for rapid fabrication. Specimens were fabricated from foam blanks or built up from layers as quickly as they were needed for wind tunnel testing, i.e., within 20 minutes. 

With rapid manufacturing established, the research turned to creating the other components of the cyber-physical optimization framework, including the optimization algorithm, specimen manufacturing strategy, wind tunnel testing approach, and data analysis procedure. All components were designed to work together seamlessly, maximize throughput, and give confidence that a near-optimal solution was achieved (without an exhaustive search). Wind tunnel experiments and cyber-infrastructure developments were conducted at UF’s NSF-sponsored Natural Hazard Engineering Research Infrastructure (NHERI) Experimental Facility. 

Through cyber-physical optimization, a series of case studies were explored to validate the proposed approach and provide useful data to wind engineering community. Case studies included aerodynamic modification features such as setbacks, corner modifications, side protrusions, and vented floors. These features were explored through both options of continuous (freely varying) and combinatorial (selected from discrete set) optimization.  

Key Outcomes

Key outcomes of the research include:

• Developed manufacturing strategies to fabricate specimens on demand, enabling the proposed cyber-physical optimization approach. Strategies included minimizing toolpath distances, conducting parallel manufacturing and testing, modifying existing models for reuse, and assembling models from modular layers.
• Created optimization algorithms to handle continuous optimization problems, where surrogate models guided adaptive sampling to efficiently explore the design space. 
• Developed optimization algorithms for combinatorial optimization problems by incrementally expanding the design space and using previous results to identify promising candidates as the design space grows.
• Demonstrated the cyber-physical aerodynamic shape optimization framework’s ability to converge efficiently toward families of promising tall building geometries by seamlessly integrating numerical optimization, rapid specimen manufacturing, and wind tunnel experimental evaluation. 
• Generated wind tunnel results for aerodynamic modification features such as setbacks, corner modifications, side protrusions, and vented floors, through both pre-established test matrices and the developed optimization approach. 

Intellectual Merits

The cyber-physical framework enables the exhaustive experimental exploration of candidate building designs and, therefore, has the potential to discover new and innovative designs to deliver taller, lighter, and more sustainable buildings. This project demonstrated that a building’s shape can be treated as a user-constrained continuum without sacrificing the reliability of physical response testing or settling for a small subset of discrete options. By integrating wind tunnel testing into exploration of candidate designs, the approach eliminates numerical approximations and challenges associated with computational fluid dynamics. By integrating advanced manufacturing, the approach provides a more complete exploration of the design space than traditional trial-and-error design approaches. The methodology provides a new path for various stakeholders to work at the same table and interface with technology that lowers current barriers to creativity and efficiency. The research helps drive the future of engineering design as it trends toward optimization and automation.

Broader Impacts

This approach to engineering design has broad societal impacts including more efficient use of limited resources, exemplary academia-industry collaboration, and exciting new resources and knowledge for researchers and practitioners. Specifically, the results of the project: (i) enable the efficient use of resources while meeting growing demands for urban densification through new approaches to tall building design; (ii) close the gap between fundamental research and engineering practice through a mutually beneficial collaboration with industry partners; (iii) bring together architects, engineers, and wind tunnel facilities in a transparent and collaborative environment; (iv) enhance the capabilities of NHERI through additional cyber-infrastructure resources that integrate advanced manufacturing with traditional testing methods; and (v) encourage payload studies across the research community that will leverage the generated aerodynamic database from this project and made available via DesignSafe.

Last Modified: 04/30/2025
Modified by: Zhaoshuo Jiang