Microwave nondestructive testing of cement based materials

In this paper, the microwave based approach for the nondestructive testing of cement based materials and concrete structures is presented. The permittivity of a number of concrete samples having various material compositions has been determined using the proposed approach, which actually helps in distinguishing these samples. It is also observed that for the cement based samples the permittivity is increasing with water to cement (w/c) ratio. Since water to cement ratio directly predicts the compressive strength of sample, the higher permittivity value indicates lower compressive strength.