Providing solutions for bridge inspection without the need for costly shutdowns.
Bridges which develop faults in construction materials over time can face major repairs and, in extreme cases, are shut down. Safety problems, traffic disruption and road closures can result. Our research sought to find new ways of inspecting structures without the need for costly shutdowns.
An 'early warning' system
Our research enabled bridges that previously had to be manually inspected to be accurately and safely monitored using acoustic emission (AE) techniques. AE acts as an early warning system to prevent major structural repair.
The technology uses passive high frequency sensors, placed externally on the surface of the structure under test, to detect energy released from growing defects, up to many meters away. The method monitors 100 per cent of the structure, even the internal details and inaccessible areas. Active flaws are located, enabling defects to be identified early, monitored and managed.
Researchers at the School of Engineering developed the technique, which has been commercialised by Mistras Group Ltd, enabling the company to greatly increase its turnover.
Our Knowledge Transfer Partnerships have helped Mistras Group Ltd become a market leader, claiming over 85% of the global market share in sensors and equipment sales.
This research has directly increased worldwide awareness of the benefits of AE testing. Mistras Group Ltd is now the market leader in the field with international contracts include the San Francisco Oakland Bay Bridge (£3.4 million), the Anthony Wayne Suspension Bridge (£1 million), and the Manhattan and Ben Franklin Suspension Bridges.
The technique continues to be extended, improved and tested in other fields including the aerospace industry.
- Holford, K. M. et al. 2001. Damage location in steel bridges by acoustic emission. Journal of Intelligent Material Systems and Structures 12 (8), pp.567-576. (10.1177/10453890122145311)
- Holford, K. M. and Carter, D. C. 1999. Acoustic emission source location. Presented at: International Conference on Damage Assessment of Structures (DAMAS 99) Dublin, Ireland 28-30 June 1999. Published in: Gilchrist, M. D. , Dulieu-Barton, J. M. and Worden, K. eds. Damage Assessment of Structures. Key Engineering Materials Vol. 167/68. Durnten-Zurich: Trans Tech Publications. , pp.162-171.