Health monitoring of cracked concrete structure by impedance approach

Abstract

Cracks/damages in concrete structures are the core concern for reduction of service life of infrastructures. Therefore, the effective technique is required for the prevention of cracks growth to improve the durability of structures. The cracks growth can be minimised by the incorporation of bacteria in the cementitious materials. The development of calcium carbonate heals the cracks automatically without any kind of human effort. The health of structures can be monitored and the presence of damages/cracks can be determined using various structural health monitoring techniques. In this paper, the research is focused on the monitoring of concrete cubes to explore the effect of bacteria. Two types of cube specimens were considered such as control concrete and bacterial concrete cubes, respectively. The six cubes of control concrete and six cubes of bacterial concrete of dimension 150 × 150 × 150 mm were cast. The compressive load of 300 kN was applied on control concrete cubes and bacterial concrete cubes to induce the incipient cracks/damages. After inducing the damages in the cubes, these cubes were tested after 7 days and 28 days curing. It was observed that the compressive strength of bacterial concrete was increased with respect to the control concrete by 19 % and 23 % at 7 and 28 days, respectively. The Electro-Mechanical Impedance (EMI) technique was used for monitoring the development of strength in both the cubes continuously. Piezo-ceramic lead Zirconate Titanate (PZT) patches were used to extract the signature. Admittance signatures were determined to access the health of cube specimens. Any deviation in signature from the healthy state that is baseline signature designates the change in compressive strength of concrete cubes. The increased strength was quantified in terms of signature change. The proposed investigation is applicable for monitoring of bacterial concrete structures. The research paper will be resulted new research directions and develop sustainable advancements in concrete technology.