Study on Scaled Model with Distortion of Free Vibration of Longitudinal Ring-Stiffened Large Thin-walled Cylindrical Shell

Abstract

For the design of scaled model and similarity prediction of vibration of 300,000m3 blast furnace gasholder body, based on energy method and discrete stiffening theory, the scaling principle relation of gasholder body free vibration are derived. By using the thickness scale factor of the gasholder body skin and rib is distorted, and utilizing the stiffness equivalence, respectively, gasholder body scaled models (stiffened rib equivalent to rectangle) with geometric distortion and with both geometric and material distortion are designed and fabricated respectively. The free vibration of distortion similarity prediction of gasholder body prototype is carried out by the method of simulation and test. Results show that both two kinds of gasholder body scaled models, can predict the prototype frequency more accurately by using the similarity coefficient calculated by the average bending stiffness of column, ring rib, and wind-resistant ring. The proposed design method and scaling principle relation for gasholder body scaled model with free vibration and distortion are suitable for the design of scaled model distortion and similar prediction of free vibration of longitudinal ring-stiffened large thin-walled cylindrical shells with T-shaped and I-shaped stiffeners.