Vibration behaviors of cylindrical shell with bolted joint effects: An experimental study

Abstract

The linear and nonlinear dynamics of a bolted cylindrical shell under a point excitation were experimentally investigated. The tests have been carried out through methods of the hammer test and sweeping frequency test. This paper aims to discover the effect of bolt joints on shell vibration, including the effects of bolt number, tightening torque, and excitation levels. The natural characteristics were analyzed by utilizing natural frequency and mode shapes. The nonlinear dynamic characteristics were analyzed through amplitude-frequency curves. The resonance frequency, resonance amplitude, and damping ratio under different tightening torques and excitation levels were investigated. Results show that: the number of bolts can not only change the value and order of the natural frequencies but also the shapes of the mode; The low tightening torque and larger excitation levels strongly lead to more complex nonlinear dynamics of shell structures.