ASSESSMENT OF BUFFETING IN THE WAKE EFFECT ON BRIDGE AERODYNAMIC STABILITY BASED ON EXPERIMENTAL MODELLING

Abstract

Introduction. This paper addresses the problem of aerodynamic stability of bridge structures, specifically the phenomenon of buffeting. The relevance of the study is driven by regular accidents and failures of bridges, among the causes of which are insufficient consideration of wind effects and aerodynamic instability of structures. The aim of this work is to experimentally assess the aerodynamic stability of a two-span road bridge (with a central span length of 130m) considering the possible occurrence of buffeting. Methods. The research methodology includes manufacturing a physical model of the superstructures with geometric and dynamic similarity, conducting static tests to determine aerodynamic coefficients, and dynamic tests of the aerodynamic stability of the model. Key results. Experimental studies on section models have shown that buffeting can occur in a superstructure located in the aerodynamic wake behind another — with the inclination of the structure relative to the oncoming flow and the difference in the overall dimensions of the fairings playing a critical role. Experimental modelling in wind tunnels remains the key method for assessing the possibility of aerodynamic instability phenomena in long-span bridges. Refinement of computational models will reduce the risks of bridge structure failures caused by wind effects.