Concrete pavement with microwave heating enhancement functional layer for efficient de-icing: Design and case study

Abstract

As traditional de-icing methods, such as applying road de-icing salt and mechanical methods, are inefficient and cause environmental pollution, a concrete pavement structure with a microwave heating enhancement functional layer (MHEFL) is proposed in this study. First, microwave heating (MH) test of magnetite with different particle sizes was performed and the mechanical strength of microwave-absorbing concrete (MAC) was tested to determine the limestone replacement particle size. Then, MH tests were performed to investigate the influence of ice covering on the heating ability of MAC and to study the temperature distribution at different depths. The results indicated that, when magnetite was used to replace limestone, magnetite particle sizes in the range of 16.0–19.0 mm improved the mechanical strength and MH rate. Water producted by ice degraded the heating performance of MAC; therefore, the critical de-icing period for eliminating this influence was determined to be 60–120 s. The optimal thickness of the functional layer was determined to be 3 cm. Finally, the pavement for microwave de-icing test was paved; field results indicated that the de-icing rate of the MHEFL pavement was increased by 60%, and the microwave leakage intensity of 2.710 W/cm2 satisfied the safety requirements. The results of this study indicated that the application of an MHEFL for road de-icing is effective and environment friendly as it dispenses with the need for using the de-icing salt.