摘要
通过对单根高强钢丝和拉索的张拉破坏试验,获得了单根钢丝中裂纹扩展、钢丝破断及索中断丝点附近和远离声源处的声发射全波形。比较不同声源的波形、频谱及时频特征,结果可以看到,钢丝破断的全波形能量及持续时间都要远高于裂纹扩展信号,但其幅值与裂纹扩展的最大幅值相当;钢丝破断声源频谱峰值突出,基本都在43 kHz,在全波形持续时间范围内,绝大部分能量都分布在一条43 kHz的等频率时间带上;裂纹扩展波形包含几个频带,最大峰值出现在50-60 kHz,高频部分出现在波形初至段,随时间增长,高频部分快速消失;断丝声源在索中传播一段距离后,能量会出现衰减,低频部分所包含的能量相对增多。
Through tension testing of a single wire and cables,acoustic emission （AE ）waveforms for wire crack expansion, wire breakage and cables damage were gained. Comparing waveforms, spectra and time-frequency characteristics of different sound sources,the results illustrated that energy and continuous time of a wire breakage are more higher than those of a crack expansion signal,however,its amplitude is close to the maximum one of crack expansion;the spectrum peaks of a wire breakage sound source are very obvious,mostly appear near 43 kHz,the most energy distributes in a frequency band containing 43 kHz within its whole continuous time;the spectrum of a crack expansion signal contains four frequency bands,the maximum peaks appear within 50-60 kHz,and the higher frequency parts appear at the front of the waveform,they quickly disappear with increase in time;a wire breakage sound propagates in a cable,its energy attenuates and the energy contained in lower frequency parts increases relatively.
出处
《振动与冲击》
EI
CSCD
北大核心
2014年第4期54-59,共6页
Journal of Vibration and Shock
基金
土木工程防灾国家重点实验室自主研究课题基金(SLDRCE08-A-05)
