Combination of Inspection and Monitoring Techniques for the Detection of Fractures in Concrete with Self-healing Properties

For applications studying fracture mechanical properties of concrete or the in-situ performance of cementitious materials non-destructive testing (NDT) and monitoring techniques (structural health monitoring, SHM) are beneficial. This will be demonstrated for a special application developing concrete exhibiting properties to heal or seal cracks (Jonkers 2011, Van Tittelboom et al. 2011). A development of a new material is typically done starting on a laboratory scale and ending up with demonstrating the techniques at real constructions. For the particular development – selfhealing concrete – it was found that a combination of inspection and monitoring techniques is most useful. This includes ultrasonic (UT), vibrational testing and acoustic emission techniques (AET). With AET (Grosse & Ohtsu 2008) can the activation of healing agents be monitored as well as the opening of cracks under load. Since this technique is time consuming and laborious more efficient NDT techniques are required to help proving the performance of the new material to the stakeholder on the construction site. This could be ultrasonic or vibration testing. The development and application of NDT inspection and monitoring techniques will be described as well as the combination of these techniques with simulations and material developments.