Internal crack detection in concrete pavement using discrete strain sensors

Cracking in concrete pavements is a major concern for their performance, especially the existence of the internal bottom-up cracks. These cracks may induce water penetration in-pavement structure and foundation, resulting in-pavement degradation. Early detection of the hidden cracks in concrete pavements can expedite timely maintenance, which improves the safety of the infrastructure. This paper develops a detection system for internal crack location and propagation using discrete strain sensors at the bottom of the concrete pavements. In this study, based on linear elastic fracture mechanics, a theoretical approach is derived from locating the bottom-up crack and tracking the crack propagation using a minimum of two discrete in-pavement strain sensors. Experimental results showed that the proposed crack detection approach with two discrete strain sensors could detect bottom-up cracks with an average measurement accuracy of 82.4% for three specimens tested in the laboratory. This study may provide an alternative technique to detect hidden bottom-up cracks in concrete pavements.