Experimental analysis of forced nonlinear vibrations of beams with breathing cracks

• Дата: 2017
• Автори: Полищук, О. Ф., Аврамов, К. В., Мягкохлеб, К. Б.
• Формат: Стаття
• Мова: Russian
• Опубліковано: Journal of Mechanical Engineering 2017
• Теми: forced nonlinear vibrations; beam; crack; вынужденные нелинейные колебания; стержень; трещина; УДК 539.3; вимушені нелінійні коливання; стрижень; тріщина
• Онлайн доступ: https://journals.uran.ua/jme/article/view/105640
• Назва журналу: Journal of Mechanical Engineering

The cracks are one of the most common reasons of the structure damage leading to accidents. In order to avoid these damages, it is very important to reveal the cracks in time. The aim of the research, which is treated in this paper, is experimental determination of the diagnostic criterion of the crack appearance. The formation of the breathing crack is diagnosed according to the parameters of the nonlinear vibrations, which are sensitive to the cracks breathing. The parameters of the nonlinear vibrations can be used as diagnostic criterion of the crack formation. The forced vibrations experimental data of the beams with big depth cracks are considered. The kinematic excitation of the beam is reproduced by the shaker. The data of the vibrations analysis are shown on the frequency responses. The Fourier analysis of the periodic vibrations is carried out. The vibration hysteresis is analyzed experimentally. The data of the Fourier analysis are shown on the frequency responses. The amplitudes of the first and the third harmonics of the Fourier series are shown. The quenching is indicated only for the amplitudes of the first harmonic. The amplitudes of the second and third harmonics are shown on the separated figure