Damage Detection of Concrete Beams using Nonlinear Features of Forced Vibration

A new indicator is proposed to facilitate the detection of newly induced damage in reinforced concrete (RC) beams, based on the transient characteristics of nonlinear vibration. Two full-scale RC beams, one reinforced with externally bonded fiber-reinforced-polymer sheets, are tested to develop the proposed damage indicator. Both beams are statically and dynamically loaded to correlate the dynamic characteristics of the beams to the damage level. A phenomenological model is developed to simulate the general behavior of cracked concrete members with a softening Duffing oscillator. Numerical results and test data show that the indicator rapidly increases with the severity of damage and is very sensitive to cracking even under service loads. The indicator is directly related to the transient features along crack surfaces and requires no baseline in practical applications. Experimental test results also show that the fundamental natural frequency of the strengthened beam suddenly decreases at the initiation of cracking and then remains nearly constant while natural frequency of the unstrengthened beam decreases continuously as the beam experiences concrete cracking and reinforcement yielding.

[1]  Ben H. Jansen,et al.  The dynamic behavior and vibration monitoring of reinforced concrete beams , 1998 .

[2]  Shuwen Pan,et al.  Damage Detection of A Health Monitoring Benchmark Building Using Hilbert-Huang Spectral Analysis* , 2002 .

[3]  Genda Chen,et al.  Condition Assessment of Concrete Structures by Dynamic Signature Tests , 1999 .

[4]  N. Huang,et al.  The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis , 1998, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[5]  H J Salane,et al.  DYNAMICS APPROACH FOR MONITORING BRIDGE DETERIORATION , 1981 .

[6]  Antonio Nanni,et al.  Strengthening of bridge G-270 with externally bonded CFRP sheets , 1999 .

[7]  Sami H. Rizkalla,et al.  Fiber Reinforced Polymer Reinforcement for Concrete Structures , 1999, SP-188: 4th Intl Symposium - Fiber Reinforced Polymer Reinforcement for Reinforced Concrete Structures.

[8]  O. S. Salawu Detection of structural damage through changes in frequency: a review , 1997 .

[9]  John T. DeWolf,et al.  Experimental Study of Bridge Monitoring Technique , 1990 .

[10]  U. Meier STRENGTHENING OF STRUCTURES USING CARBON FIBRE/EPOXY COMPOSITES , 1995 .

[11]  O. S. Salawu,et al.  BRIDGE ASSESSMENT USING FORCED-VIBRATION TESTING , 1995 .

[12]  Genda Chen,et al.  Stability of Nonlinear Vibration in Cracked Concrete Structures , 2000 .

[13]  Yu Lei,et al.  Hilbert-Huang Based Approach for Structural Damage Detection , 2004 .

[14]  Genda Chen,et al.  DESTRUCTIVE AND NON-DESTRUCTIVE TESTING OF BRIDGE J857, PHELPS COUNTY, MISSOURI. VOLUME II - FEASIBILITY STUDY ON DAMAGE DETECTION OF RC STRUCTURES USING DYNAMIC SIGNATURE TESTS , 2001 .

[15]  C. L. Nikias,et al.  Higher-order spectra analysis : a nonlinear signal processing framework , 1993 .

[16]  George C. Yao,et al.  Damage diagnosis of steel frames using vibrational signature analysis , 1992 .

[17]  Charles R. Farrar,et al.  A summary review of vibration-based damage identification methods , 1998 .

[18]  D. J. Ewins,et al.  Modal Testing: Theory and Practice , 1984 .

[19]  Charles R. Farrar,et al.  Damage identification and health monitoring of structural and mechanical systems from changes in their vibration characteristics: A literature review , 1996 .

[20]  J. S. Rao Advanced theory of vibration , 1992 .