Dynamic Response of a SDOF system subjected to simulated downburst winds

This study provides an investigation of the dynamic response of a Single Degree Of Freedom (SDOF) structure subjected to simulated downburst winds. Wind speed time histories were simulated using an analytical model of a downburst wind field and an Autoregressive Moving Average (ARMA) turbulence simulation (Chay et al 2005). A variety of turbulence and damping conditions were investigated. The structure is a simple spring-mass-damper system. The investigation was conducted in the time domain using a direct numerical integration of the equations of motion (Paz 1997). The response of the system under the action of the downburst winds is compared to that of the same system subjected to simulated boundary layer winds. The paper also presents an investigation of the affect that various downburst traits, such as the radius to maximum velocity and storm direction, have on the dynamic response. Finally, a case study is presented which examines the dynamic response of the SDOF system when subjected to a simulation of the 1983 Andrews Air Force Base downburst (Fujita 1990).