Use of microwaves for damage detection of fiber reinforced polymer-wrapped concrete structures

被引:87
作者
Feng, MQ [1 ]
De Flaviis, F
Kim, YJ
机构
[1] Univ Calif Irvine, Calif Inst Telecommun & Informat Technol, Dept Civil & Environm Engn, Irvine, CA 92697 USA
[2] Univ Calif Irvine, Dept Elect & Comp Engn, Irvine, CA 92697 USA
来源
JOURNAL OF ENGINEERING MECHANICS-ASCE | 2002年 / 128卷 / 02期
关键词
microwaves; damage; concrete structures; fiber reinforced materials; polymer; imaging techniques;
D O I
10.1061/(ASCE)0733-9399(2002)128:2(172)
中图分类号
TH [机械、仪表工业];
学科分类号
0802 ;
摘要
Jacketing technology using fiber reinforced polymer (FRP) composites is being applied for seismic retrofit and rehabilitation of reinforced concrete (RC) columns designed and constructed under older specifications. In this study, the authors develop an electromagnetic (EM) imaging technology for detecting such damage as voids and debonding between the jacket and the column, which may significantly weaken the structural performance of the column otherwise attainable by jacketing. This technology is based on the reflection analysis of a continuous EM wave sent toward and reflected from layered FRP-adhesive-concrete medium: Voids and debonding areas will generate air gaps which produce additional reflections of the EM wave. In this study, dielectric properties of various materials involved in the FRP-jacketed RC column were first measured using a plane-wave reflectometer. The measured properties were then used for a computer simulation of the proposed EM imaging technology. The simulation demonstrated the difficulty in detecting damage by using plane waves, as the reflection contribution from the voids and debonding is very small compared to that from the jacketed column. In order to alleviate this difficulty, dielectric lenses were designed and fabricated, focusing the EM wave on the bonding interface. Finally, three concrete columns were constructed and wrapped with glass-FRP jackets with various voids and debonding conditions artificially introduced in the bonding interface. Using the proposed EM imaging technology involving the especially designed and properly installed lenses, these voids and debonding areas were successfully detected. This technology can be used to assess the jacket bonding quality during the initial jacket installation stage and to detect debonding between the column and the jacket caused by earthquake and other destructive loads.
引用
收藏
页码:172 / 183
页数:12
相关论文
共 16 条
[1]   Imaging of concrete structures [J].
Buyukozturk, O .
NDT & E INTERNATIONAL, 1998, 31 (04) :233-243
[2]  
CHASE SB, 1997, PUBLIC ROADS, V60, P16
[3]   Electromagnetic image reconstruction for damage detection [J].
Feng, MQ ;
Liu, C ;
He, XM ;
Shinozuka, M .
JOURNAL OF ENGINEERING MECHANICS-ASCE, 2000, 126 (07) :725-729
[4]  
FENG MQ, 2000, P INT S SMART STRUCT, P118
[5]  
FENG MQ, 2000, P WORKSH MIT EARTHQ
[6]  
FLAVIIS FD, 1998, ELECTROMAGNETICS, V18, P35
[7]  
FLAVIIS FD, 1997, P APPL COMP EL ACES, P17
[8]  
FLAVIIS FD, 1996, P IEEE MTT S INT MIC, P1047
[9]  
HAROUN MA, 1997, P 3 US JAP BRIDG WOR
[10]   GIMA ground penetrating radar system for monitoring concrete bridge decks [J].
Huston, D ;
Hu, JQ ;
Maser, K ;
Weedon, W ;
Adam, C .
JOURNAL OF APPLIED GEOPHYSICS, 2000, 43 (2-4) :139-146