基于输电塔风致响应的节点螺栓脱落损伤自动诊断的小波识别方法

以法兰螺栓联结为节点连接型式的输电塔架结构是一类应用广泛的结构型式。其中节点螺栓脱落损伤是一种常见的损伤形式。为了确保电力工业的正常运行,及时进行法兰联结节点螺栓松动损伤的诊断是十分必要的。本文依据输电塔结构塔身竖杆法兰联结节点风致响应的特点,推导了只与结构的损伤程度有关,与外加的风荷载无关的塔身竖杆节点风致竖向应变响应方差的归一化公式,并借助于噪声抑制能力强且对突变信号敏感的小波变换方法对该统计方差进行了小波变换分析,达到了对螺栓脱落损伤位置的有效识别,实际输电塔法兰螺栓松动损伤的仿真分析表明,本文提出的方法是有效而可行的,具有一定的实践价值。

The wavelet recognition method of joint bolt looseness damage diagnosis based on the wind-induced responses of transmission towers

The flange joint is a common connection form of highrise steel tower structure,such as the transmission tower,and the bolt looseness of flange is the damage usually caused in the structure.It is extremely essential to carry out the joint damage diagnosis to ensure the normal operation of power industry.This paper has carried out the fundamental research on the damage diagnosis of bolt looseness in the joint of flange in the transmission tower under the wind loading.By deducing the damage characteristic that is sensitive to damage and independent of loading,accurate diagnosis of damage of bolt looseness in the joint of flange is made by applying the wavelet transform method and sensitive characteristic of the wave signals.The authors carried out the simulation analysis under the action of different wind loads.The results indicate that this method can effectively achieve the recognition of bolt looseness damage with great antinoise ability.