Wind-Induced Failures of Flexible Structures

This paper will focus on structural failures caused by below-design wind events. The structure is flexible and behaves in ways not common to building designers. The failure mechanism in each case is atypical and not covered within the design guides or building codes. The mechanisms covered in this paper include torsional galloping, vortex-induced vibrations, and rain-wind-induced vibrations. Case studies for these mechanisms include lighting poles, bridge cables, and single-axis solar trackers. Each case study will explore the mechanism, failure modes, investigative methodology, and preventive or repair strategies. Lessons learned from these failures will enable a relatively better design of flexible structures sensitive to wind. Understanding these mechanisms will also enable the development of appropriate theories for forensic engineers.