Bridges, Tunnels and other Transportation Structures
Full Session with Abstracts
A sensing skin has been employed to detect and monitor cracks in reinforced concrete members. This sensing skin is constituted of a flexible electronic termed the soft elastomeric capacitor that is capable of detecting, localizing, and quantifying cracks that form over the structure when a plurality of sensors are deployed onto the surface of a structure. The soft elastomeric capacitor is a low cost and robust sensing technology that has previously been studied for the monitoring of fatigue cracks in steel bridges. The sensor is highly elastic and as such offers a unique capability for monitoring the large crack openings that can be associated with concrete structures, in addition to its demonstrated ability to detect and localize damage over the surface of a structure. This work presents an experimental investigation on the use of the soft elastomeric capacitor-based sensing skin for the monitoring of moment-induced cracks in concrete structures.
Here, a series of experimental validations are conducted on two concrete members. Initially, the sensing skin was attached to a scale-model concrete sample with steel reinforcement to evaluate its ability to both detect and monitor cracks in a three-point loading configuration. Thereafter, the sensing skin was deployed on a single beam of a larger structure composed by two post-tensioned beams connected by a reinforced concrete deck. Results show that the sensing skin was capable of detecting, localizing, and quantifying cracks that formed in both the reinforced and post-tensioned concrete specimens. Additionally, the sensor is shown to offer a good signal-to-noise ratio and represents a cost-effective alternative to current sensing technologies for the monitoring of cracks in concrete structures.