Unlike a typical strain gauge which monitors the amount of strain at the point where it is attached to the structure, CrackFirst senses the actual mount of fatigue damage that a structure has suffered. It can be used on any welded steel construction which sees cyclic loading, such as ships, bridges, cranes and offshore structures.

The principal advantage of such a system is that it provides valuable information on the rate at which the fatigue design life is being expended, and can therefore be used to set inspection intervals according to usage rather than elapsed time. Such sensors are of most benefit for structures in which fatigue is the primary limit state, especially in situations where inspection and repair are difficult or impossible, or where structural failure would have significant consequences with respect to safety and/or financial loss.

Bob John, chief executive of TWI said, 'Innovation is only useful if it is made available to industry. CrackFirst is an excellent example of the smooth transition from the research and development environment to the commercial world and the utilisation of new technology.'

MJInformation No: 22230