RESPONSE OF CABLE ROOFS TO WIND

A nonlinear solution is formulated for a single hanging cable and flat rectangular and circular cable roofs under the effect of the initial tension and the applied loads. The solution is based on a small strain large displacement theory.; The linear deflection of a curved tension roof under additional static loads is studied using the assumption that the deflection under these additional loads is small with respect to that under the initial loads. Approximate analytical solutions for the initial and additional deflections are obtained.; The linear undamped free vibration problem of a flat cable tension roof with any boundary is considered using the assumption that an orthogonal, isotropic network can be replaced by an equivalent membrane found by energy considerations. Free vibration is solved for rectangular, circular and elliptical boundaries. For the elliptical flat cable roof, a simplified solution, very well suited for practical applications, is derived.; The partial differential equation of free undamped vibration of a general curved membrane surface is formulated and solved, with some simplifications, for a rectangular hyperbolic paraboloid cable roof. The general solution outlined above is extended to include the case of the circular hyperbolic paraboloid cable roof.; The problem of a free vibrating membrane backed by a cavity with openings is theoretically studied and complemented by experimental verification of the theory. Theoretical and experimental values for frequency reduction due to inertia are given.; The statistical theory of wind forces is reviewed and applied to determine the dynamic response of cable roofs to wind loading. The problem of air-structure interaction is outlined and parameters for the aerodynamic and acoustical damping ratio are described. The behaviour of cable roofs in turbulent wind is studied in the wind tunnel using two aeroelastic models. The similarity requirements for modelling are reviewed with special attention being paid to the effect of the air enclosed under the roof. A similarity law for the modelling of this enclosure is presented and its role in free vibration as well as wind induced vibration is investigated. A wind tunnel study of a large tension roof is described.; The design implications of cable tension roof behaviour under turbulent wind load are discussed.