Vibrations of a Nonlinear Mechanical System Simulating a Cracked Body

The paper presents the results of numerical investigation of forced and damped vibrations of a mechanical system with a bilinear restoring force, which simulates a closing crack. Among the vibration characteristics studied, the most damage-sensitive ones are the level of nonlinear distortions and relative amplitudes of the displacement, velocity, and acceleration waves in super- and subresonance vibrations. At the same time, these characteristics are shown to depend substantially on the level of vibration damping in the system.