Preliminary Study on Broadband Resonance of Shaking Table Based on the Compressibility of Gas

In order to improve the performance of the shaking table, a vibration-enhanced shaking table which exploited broadband resonance was constructed. The broadband resonance was realized by an adjustable stiffness mechanism which exploited gas compressibility. Different from the traditional device, a gas filled cylinder (GFC) was mounted between the shake table and the exciter, and a pressure regulator was designed to regulate the gas pressure of the GFC. The natural frequency of the designed shaking table can be adjusted based on the compressibility of gas during the test. The principle of stiffness adjustment was theoretically analyzed and a series of experiments were carried out to investigate the effects of regulating the natural frequency. The experimental results indicate that the amplitude can be twice amplified and the natural frequency can be regulated between 20.Hz and 60.Hz.