Mathematical Formula to Evaluate the Required Gap Distance and Impact Forces from Wind-Induced Pounding of Tall Buildings

Extreme wind events are becoming a higher risk within dense locations involving the newer generation of taller and slender structures. When tall structures are constructed in close proximity to one another, pounding of structures can transpire when subjected to such extreme lateral loading (e.g., wind or earthquakes) when the separation distance is insufficient. Damages from structures due to pounding can result, ranging from minor to major disasters, ensuing in a possibility of a total collapse. A separation distance between the interactive structures can be determined to mitigate a pounding event. This study focuses on developing a mathematical formulation through an optimization process to determine the required separation distance between two adjacent structures to mitigate wind-induced pounding. Next, the developed mathematical formulation will be further developed to determine the maximum pounding force of the two adjacent structures when the mitigation of a wind-induced pounding cannot be achieved. The study will first validate wind loads on two equal-height structures in proximity aided through large eddy simulations (LES). A finite element method (FEM) model is then used to validate the structure’s performance (i.e., deflections and pounding forces) from the captured wind loads. A genetic algorithm (GA) is utilized to develop the mathematical formula to estimate the required separation distance and maximum pounding force while optimizing the fitting parameters. Results show that taller structures are also more susceptible to more vital pounding forces when such structures become closer in proximity to one another. Contour plots were conducted which map the relationship between the mean wind velocity and natural frequency of the structures for the separation gap distance and the mean wind velocity and separation gap distance for the maximum pounding force.