Wind-Induced Pounding of Tall Structures in Proximity

Pounding of adjacent structures under lateral loads (e.g., earthquake and wind) due to proximity has been a major cause of building damages in the past. The effects of pounding can be mitigated by providing a suitable gap distance between structures, adequate shock absorbers or by designing for the additional pounding loads. However, if not properly considered, these abnormal supplementary loads can damage the structures, notably when the attentive structure experiences a dynamic vibration in an out-of-phase order. Multiple pounding incidents have been reported to occur under lateral loads, which resulted in local and global damages. With the new generation of tall buildings, which are becoming taller and more flexible, these structures are becoming more susceptible to wind-induced pounding due to the large deflections developed during high wind problematic affairs. The present study has considered a detailed three-dimensional pounding-involved response analysis of two adjacent structures using the Finite Element Method (FEM) under nonlinear dynamic wind-induced load. This study examines the pounding between two identical tall buildings with a typical outer shape. First, the wind loads on these structures were evaluated using Large Eddy Simulations (LESs). Then, the extracted wind loads from the LES model were applied to a validated finite element model to determine the expected response (i.e., building deflections and accelerations). Different dynamic characteristics of the building and wind magnitudes were examined to assess their effects on the building responses. Results concluded that the pounding force could be correlated to building height, gap distance, and dynamic structural properties of the colliding buildings.