Hybrid simulation of thunderstorm outflows and wind-excited response of structures

Starting from the records detected by the monitoring network of the European Projects “Wind and Ports” and “Wind, Ports and Sea”, this paper proposes a novel strategy for simulating the wind velocity field of thunderstorm outflows. A model of the wind field along a vertical axis is first proposed. Its different ingredients and the inherent sources of randomness are then separated into five groups and a hybrid technique for the simulation of thunderstorm outflows is formulated. This technique is applied to generate artificial time-histories of the aerodynamic wind loading on three real slender vertical test structures whose dynamic response is evaluated by means of a time domain integration of the equations of motion. The results are analysed in a probabilistic frame aiming to inspect the distribution of the maximum value of the response, the role of the aerodynamic admittance, the relevance of the resonant part of the response, and the contribution of higher vibration modes in parallel with the classic analysis of the response of structures to synoptic extra-tropical cyclones. The conclusions draw some prospects on the joint calibration of the response spectrum technique and the time domain simulations.