The attempts to identify damping changes in a cracked beam can improve the accuracy of the nonlinear crack identification method. For the purpose of this aim, a parametric nonlinear equation of motion is obtained using the Euler–Bernoulli beam theory and parametric nonlinear breathing crack assumptions. Several experiments were conducted to identify the effect of breathing cracks on changing the damping value in nonlinear vibrations of a cracked beam. Experimental tests have revealed that increasing the crack depth and the level of excitation enlarges the damping coefficient in a vibrating beam. For this reason, the effects of the excitation force and crack depth on the structural damping coefficient are investigated. The obtained results indicated that considering the nonlinear response of a cracked beam and measuring the value of the damping changes can significantly improve the accuracy of the nonlinear crack identification method.

识别裂纹梁中阻尼变化的尝试可以提高非线性裂纹识别方法的准确性。为此目的，使用欧拉-伯努利梁理论和参数非线性呼吸裂纹假设获得了参数非线性运动方程。进行了一些实验来确定呼吸裂纹对裂纹梁非线性振动中阻尼值的影响。实验测试表明，增加裂纹深度和激发水平会增大振动梁的阻尼系数。因此，研究了激振力和裂纹深度对结构阻尼系数的影响。