SMUTI is Strength Monitoring Using Thermal Imaging.
SMUTI is a totally new method of monitoring the early strength development of shotcrete. The whole of the shotcrete tunnel lining can be scanned from a safe position in real time using a thermal imaging camera and SMUTI software.
SMUTI is as quick and easy as taking a photograph. To give an idea of what you see when you look at shotcrete through a thermal imaging camera, a video is posted below.
SMUTI will be accurate for the first 24-36 hours. By this time the shotcrete will typically have a strength in excess of 25 MPa.
SMUTI is a 'strength monitoring' method, not a conformity test. If the wrong shotcrete mix is delivered to the pump, the wrong strength will be calculated. Therefore conformity testing is still required to verify that the specification is being met.
SMUTI is implemented in 3 stages: