Enhanced air-coupled impact echo technique by phase analysis of signals from multiple sensors  

作　　者：Najjiya Almallah Nenad Gucunski 

机构地区：[1]New Jersey Department of Transportation,New Jersey 08625,USA [2]Department of Civil&Environmental Engineering,Rutgers University-New Brunswick,NJ 08854,USA

出　　处：《Earthquake Engineering and Engineering Vibration》2024年第2期297-310,共14页地震工程与工程振动（英文刊）

摘　　要：This paper presents an air-coupled impact echo(IE)technique that relies on the phase spectrum of the collected data to find the frequencies corresponding to the reflections from delaminations.The proposed technique takes advantage of the fact that the IE compression wave is not a propagating wave,but it is the 1st order symmetrical(S1)mode Lamb wave at zero group velocity(S1-ZGV).Therefore,it searches the phase spectra of the data collected by multiple sensors to locate the frequency corresponding to the lowest phase difference.As a result,the technique reduces the effect of propagating waves,including the direct acoustic wave and ambient noise.It is named the Constant Phase IE(CPIE).The performance of the CPIE is experimentally compared with the regular amplitude spectrum-based IE technique and two other multisensor IE techniques.The CPIE shows a performance advantage,especially in a noisy environment.

关 键 词：nondestructive testing(NDT) nondestructive evaluation(NDE) bridge inspection bridge evaluation impact echo bridge delamination concrete bridge deck air-coupled sensing MEMS 

分 类 号：U446[建筑科学—桥梁与隧道工程]