机构地区: 东南大学土木工程学院
出 处: 《振动.测试与诊断》 2005年第2期105-108,154,共5页
摘 要: 介绍了波动法测量缆索张力的基本原理及其检测技术。针对实际测量中脉冲激励下产生的应力波含噪声大及走时时差难以分辨的问题,利用相关系数选取最优小波函数并结合软阈值消噪方法,将应力波从噪声干扰中提取出来。实验结果表明,采用此方法选取的小波能更有效地消去噪声,经过修正后的小波系数重构得到的信号图清晰地反映了入射波和反射波之间的时差。 This paper describes the basic theory of cable tension measurement and its examination techno-logy by the method of vibration wave. In practical measurement, it is found that stress wave excited by the impulsion contains too much noise, so the time between two signals could hardly be distinguished. Combined with soft threshold, a method to select optimal wavelet with correlation coefficient is presented to extract stress wave from noise interference. The feasibility and practicability of the method are verified by experiment, and the noise-extracted signal that is reconstructed by the revised wavelet coefficient could clearly reflect the time between incidence wave and reflection wave.