Investigations into aerodynamics Of bridges through wind tunnel testing

Abstract

Aerodynamic studies on cable stayed bridge deck model based on newlineexperimental approach have been examined in the present investigation The newlinemost elementary tool available for the study of the aerodynamics of long span newlinebridges is the section model The section model consists of a typical rigid newlinesection of the deck geometrically and aerodynamically similar to the newlineprototype structure It is mounted in the wind tunnel in such a way as to newlinemeasure the wind induced static and dynamic drag lift and moment In the newlinepresent study the section model is instrumented specially to measure drag lift newlineand moment independently through mounting the model on stiff test rigs to newlineeliminate the resonant response under dynamic action of wind The test rigs newlineconsist of aluminium spars perpendicular to each other to measure drag and newlinelift components and a circular hallow cylinder to measure moment newlineAluminium strips spars are used in the fabrication of the test rig to have newlinebetter sensitivity and these are suitably instrumented with strain gauges The newlinetest rig is designed to measure the de coupled drag and lift forces Ball newlinebearing mechanism is used in the test rig to allow free rotation of the model at newlineone end A special circular assembly to measure moment is designed newlinedeveloped and fabricated in house and fixed at the other end of the sectional newlinemodel newline newline