Experimental crack length detection in concrete pavement using point strain sensors

In concrete pavements, one of the main deteriorations and damages is tensile cracking, which can destroy concrete pavement frame when sub surface cracks propagate to the surface because it induces water penetration in pavement structure and foundation. However, detecting the propagation, especially the crack length, of hidden cracks inside pavements is very challenging. This paper presents the results of an experimental investigation conducted to detect crack length in concrete using point strain sensors in the bottom of the simulated pavements in a bending test with four-point loading. The linear elastic fracture mechanics is used in this study to calculate the crack lengths based on the collected data from point sensors. Results for the crack length detection in experiments showed a measurement accuracy of 88.85%, 87.7%, and 81.08 % for the three specimens tested, respectively. This study provides an alternative technique to detect hidden bottom-up cracks in concrete pavements.