All structures weaken as they age, strained by the effects of extreme cold, water and salt corrosion, movement resulting from earthquakes and destabilisation caused by flooding. Such weaknesses can cause catastrophic failure if gone unnoticed. However, they can be avoided if the health of the structure is monitored, evaluated and maintained on an ongoing basis.
Structural health monitoring (SHM) involves using sensors which are permanently attached to a structure to collect data that can be used to provide real-time information on its condition. Ongoing analysis of the collected SHM data enables engineers and inspectors to observe any changes in the health of the structure, whether they be new defects or the deterioration of existing flaws.
The application of reliable data facilitates the objective assessment of a structure's ability to safely and efficiently perform its intended function. In turn, this allows operators to better plan and prioritise their maintenance programmes to ensure that their structures are able to do their job safely and efficiently.
TWI Resources
TWI has world class expertise in structural health monitoring (SHM) derived from its long history of undertaking cutting edge research into structural failures. Four factors determine the way a structure fails under load: imposed stresses; defects in the material; the immediate environment; and susceptibility of the material's microstructure. These factors produce fatigue and corrosion in metallic members which eventually lead to brittle or ductile fracture.
A current area of study is acoustic emission (AE) techniques as applied to structural health monitoring. A recent output of this work is TWI’s Acoustic Emission Hydrogen Induced Cracking detection system (AEHIC) which provides a means of identifying whether hydrogen induced cracking is going to occur, or is already in progress including how it is evolving. The resulting information can then be applied to limit the potential for pipework damage or failure, giving you greater control over your plant’s operation and performance. Download leaflet
TWI’s Vibration Monitoring and Risk Analysis System for Process Piping (VARA) uses vibration analysis, as applied to structural health monitoring, to detect structural damage. It gives operators vital data to inform their process piping maintenance strategy – providing a link between vibration analysis of pipework and the likelihood of the occurrence of fatigue crack initiation. Download leaflet
Benefits of structural health monitoring
The ability to carry out structural health monitoring (SHM) on a whole structure provides a robust, continuous monitoring process resulting in improved safety levels and operational reliability, which can lead to reduced inspection and maintenance costs.
Applications
TWI has been involved in, and continues to work on, a large number of projects related to the development of SHM systems. These are designed to focus on a range of different structural types including surface transportation systems using composite materials, wind turbines, aircraft structures, tidal stream power generation systems, storage tanks and bridges.
Project Links
For more information, please explore the following projects to read examples of structural health monitoring as applied in industry:
For more information, please email contactus@twi.co.uk.