Microwave curing process and mechanical properties study of epoxy mortars for repairing concrete pavement rapidly

Polymer mortars are used frequently to repair pavement owing to their excellent properties (mix flexural strength >= 5.75 MPa, compressive strength >= 25 MPa). To repair concrete pavement with polymer mortars rapidly, uniform microwave energy can be used to reduce hardening time of polymer mortars. In this study, the distribution of electromagnetic fields in an industrial microwave facility was optimized, and an area AG with uniform and intensive electric field was obtained. Then microwave curing process of epoxy mortars containing fly ash in the area AG was optimized, and mechanical strengths of the epoxy mortars cured in the optimum process were tested. The results show that, although the distribution of electromagnetic fields in the microwave facility is non-uniform overall, there still are some brush-fire areas, where electric field distribution is relatively uniform. Epoxy mortars added with 10 wt% fly ash can be cured rapidly (approximately 20 min) in the area AG and exhibit outstanding mechanical strengths, which can be used to repair concrete pavement rapidly.