AE energy analysis on concrete bridge beams

Title: AE energy analysis on concrete bridge beams
Author(s): S. Colombo, M. C. Forde, I. G. Main, J. Halliday, M. Shigeishi
Paper category : journal
Serial title: Materials and Structures
Abreviated Serial title: Mater. Struct.
ISSN: 1359-5997
Publisher: RILEM Publications SARL
Volume: 38
Issue: 283
Issue date: 2005-11-01
Publication year: 2005
Pages: 851 - 856
Total Pages: 6
Nb references: 5
Language: English

Abstract: Concrete bridges were built originally to have a cost-effective maintenance free life of 120 years, however both in Europe and the USA this has proved to be totally optimistic.
Concrete bridges require major maintenance after twenty to thirty years in order to extend their life.
The Acoustic Emission technique has been successfully applied to monitor and provide information on the safety of concrete bridges, but the processing of the AE data is often not trivial.
This paper proposes a method of AE analysis to assess concrete bridges based on the fact that the AE energy is one of the effective parameters to evaluate the damage of a concrete structure.
Results from experiments on concrete with different design and loading configurations are presented.
The beams were loaded in cycles and the energy during the loading and unloading phase was analysed.
It was observed during the tests that none or very low energy activity was recorded during the unloading cycles.
On the other hand such activity was increasing as the failure was approaching and the damage on the beams increased.
In the light of these observations the energy recording during each loading up and loading off cycle was computed and a new parameter, the "relaxation ratio" was introduced.
The final results were compared and combined and a proposed assessment criterion for the damage of concrete structures was obtained.
It is argued that in some cases the state of damage of bridge beams can be estimated from the AE energy analysis when approximately 45% of the ultimate load has been applied.
This criterion was then evaluated in relation to the quantitative assessment criterion recommended by the Japanese Society for Non-Destructive Inspection.
Full laboratory data and analyses are given in the paper.

Online publication: 2005-06-06
Classification: Special Issue on Nondestructive Testing in Civil Engineering
Publication type : full_text
Public price (Euros): 0.00
doi: 10.1617/14300