【摘要】 对板的振动模态进行大间距二维采样,并用二维小波对得到的模态信号进行分解,判断损伤的大致位置。在损伤位置的附近分别沿平行于板两边的方向进行加密一维采样,对采样信号进行连续小波变换,求得各点在两个方向的Lipschitz指数,判断裂纹的具体位置和尺寸。用有限元法模拟一个含穿透裂纹的矩形板结构,求解其自由振动模态,模拟结果表明,本方法准确有效。更多还原

【Abstract】 The vibration modes of the cracked plate were obtained by two-dimensional sparse sampling.The sampling signal was decomposed by the two-dimension wavelet transform to identify roughly the damage location.Then the detail vibration modes of the cracked plate were obtained by one-dimensional dense sampling near the rough damage location along the two directions paralleling to the plate edges of the plate.The one-dimensional sampling signals were analyzed by the continuous wavelet transform to calculate the Lipschitz exponents of the points in two directions,which can be used to identify the accurate location of the crack.The FE modal analysis results of a plate with a through crack showed that the crack location can be identified quickly and accurately.更多还原