Water presence detection in a concrete crack using smart aggregates  

作　　者：Qingzhao Kong Qian Feng Gangbing Song 

机构地区：[1]Department of Mechanical Engineering,University of Houston,Houston,TX 77204,USA [2]Hubei Key Laboratory of Earthquake Early Warning,Institute of Seismology,China Earthquake Administration,Wuhan 430071,China [3]Wuhan Institute of Earthquake Engineering,Wuhan 430071,China [4]School of Civil Engineering,Dalian University of Technology,Dalian,Liaoning,China

出　　处：《International Journal of Smart and Nano Materials》2015年第3期149-161,共13页国际智能和纳米材料杂志（英文）

基　　金：partially supported by the Science Fund for Creative Research Groups under Grant No.[51121005];a research project under Grant No.[51278084]from the National Science Foundation of China.

摘　　要：Liquid migrating into existing concrete cracks is a serious problem for the reliability of concrete structures and can sometimes induce full concrete structural failures.In this paper,the authors present recent research on water presence detection in concrete cracks using piezoceramic-based smart aggregate(SA)transducers.The active sensing approach,in which one piezoceramic transducer is used to generate stress waves and others are used to detect the stress wave responses,is adopted in this research.Cracks formed in concrete structures act as stress reliefs,which attenuate the energy of the signals received by the SAs.In case of a crack being filled with liquid,which changes the wave impedance,the piezoceramic transducers will report higher received energy levels.A wavelet packet-based approach is developed to provide calculated energy values of the received signal.These different values can help detect the liquid presence in a concrete crack.A concrete beam specimen with three embedded SAs was fabricated and tested.Experimental results verified that the SA-based active sensing approach can detect a concrete crack and further detect the liquid presence in the concrete crack.

关 键 词：water detection concrete crack smart aggregate active sensing piezoceramic sensors and actuators2 

分 类 号：TU5[建筑科学—建筑技术科学]