摘要
对声发射采集系统的硬件参数设置、滤噪参数设置以及声发射信号特征参数及其相关性进行了系统的试验研究。共进行了11组断铅人工激发源试验和13个混凝土试件的单轴静态拉伸试验,采用全数字化的参数-波形式声发射采集系统和三种不同型号的传感器同步采集并存储了试验过程中的声发射特征参数和波形,应用参数和波形分析相结合的方法以及波形事后提取分析等技术手段对数据进行分析。结果表明:前置放大器增益、阈值、波形采样率和采样长度、带通滤波器等有一合理参数取值;幅度、振铃、持续时间、声发射信号能量、绝对能量、信号强度这6个参数能够较好地体现混凝土轴拉损伤过程的阶段性特征;声发射幅度、振铃数、持续时间、上升时间和信号强度5个参数之间存在显著的相关性。研究成果可为采用声发射技术研究混凝土的损伤破坏过程提供参考依据。
Setting of hardware parameters,filtering parameters for acoustic emission（AE） acquiring system,and AE parameters as well as their correlations were studied systematically with tests,11 groups of pensile lead break tests and 13 concrete specimens loaded in uniaxial tension were carried out.Feature parameters and waveforms of AE signals acquired by 3 kinds of sensors during the processes of tests were stored using a digital parameter-waveform collecting system.The test data were analyzed using the parameter combined with waveform method and the post-extracting technique for waveforms.The results showed that there are reasonable values for gain of preamplifier,threshold,sampling rate,sampling length and parameters of band pass filter;amplitude,count,duration,AE signal energy,absolute energy and signal strength are suitable for evaluating the phased damage feature of concrete under uniaxial tension loading;the significant correlations among amplitude,count,duration,rise time and signal strength are found.The study results provided a reference for studying on concrete failure process using AE technology.
出处
《振动与冲击》
EI
CSCD
北大核心
2011年第5期196-204,共9页
Journal of Vibration and Shock
基金
国家自然科学基金重点资助项目(90510017)
国家自然科学基金项目资助(51009058)
水利部公益性项目(200701004)
中央高校基本科研业务费专项资金资助(2009B03014)
关键词
混凝土
轴拉
声发射
采集参数
特征参数
concrete
uniaxial tension
acoustic emission
acquiring parameters
feature parameters
