In the present paper, the concrete decontamination and decommissioning (D&D) process with a finite microwave heating source is investigated theoretically. The steel reinforcement is treated as a thin layer having dielectric properties that reflect certain parts of the incident energy. Two-dimensional heat transport within the concrete is also considered to evaluate the variations of temperature with heating time at different frequencies with and without the presence of the reinforcement bars. The results revealed that as the microwave frequency increases to, or higher than 10.6 GHz, the maximum temperature shifts toward the front surface of the concrete. Furthermore, it was observed that the temperature distribution is nearly uniform within the dimensions of the microwave applicator for a high microwave power intensity (Q0,ave ≈8.0×105W/m2) and a short heating time (t≈60 sec).
