Shaking table experimental and numerical investigations on dynamic characteristics of suspend-dome structure

To further investigate the dynamic characteristics of the suspend-dome structure, based on a prototype structure of the Lanzhou Olympic Complex Gymnasium, the method of replacing steel with Austenitic 304 stainless steel is proposed. Dynamically scaled model with a geometrical 1:20 was designed. Shaking table dynamic characteristics test was conducted using the white noise excitation method. The response of the scaled model was identified and analyzed by the transfer function method, the frequency domain decomposition method, and the Hilbert-Huang Transformation, respectively, and the measured natural frequency and damping ratio were obtained. The finite element models of the prototype and scaled model were built, and the finite element software ABAQUS completed modal analysis. The simulation results of vibration modes for the prototype structure and scaled model were analyzed. The study shows that the difference between the experimental and simulation results for the natural frequency of the scaled model is within 5%, which indicates that the testing points are reasonably arranged, the test method is correct and finite element modeling method is reasonable. The measured results of the scaled model are essentially consistent with simulation results obtained from the prototype structure by the similitude conversion, indicating that the proposed method of replacing steel with Austenitic 304 stainless steel is reasonable and scaled model is well designed. The correctness of the similarity relation between the scaled model and the prototype structure is verified. The model has closely distributed modes and more vertical modes. The first-order damping ratio identified by the dynamic characteristics test is between 1.85% and 2%.