| Microwave deicing is a new technique to clear the ice on the road raised by the engineersrecently which can deice environmentally friendly, rapidly and thoroughly. But the traditionalmaterial has the low absorbed efficiencies for microwave that the microwave deicing speed isvery slowly and it cannot be applied in practice. The paper presents paving asphalt concretewith magnetite aggregates which have a high absorbing efficiency for microwave instead oflimestone aggregates to improve the speed of microwave deicing.By adhesion test, the adhesion level of magnetite and limestone with asphalt are bothfive. But in the freeze-thaw cycles and after prolonged heating, asphalt flakes from magnetitesurface seriously than limestone. The water stability of magnetite asphalt mixture is worsethan limestone asphalt mixture. A certain amount of lime can improve the water stability ofmagnetite asphalt mixture.By pavement performance test, not add lime, compared to limestone asphalt mixture, thehigh temperature stability of magnetite asphalt mixture improves, the water stability reducessignificantly, the low temperature cracking resistance reduces a little. After mixing lime, thehigh temperature stability and the water stability of magnetite asphalt mixture improve andthe low temperature cracking resistance reduces little.By microwave heating test, the temperature of asphalt, slag, limestone, magnetiterespectively rise0.6℃,17.1℃,16.5℃,210.6℃in30s by microwave heating. The heatingrate of magnetite aggregates is12.8times the limestone aggregates. The particle size ofaggregate has no effect on the heating rate.By software simulation, drawn: the higher the content of magnetite aggregates, theshorter microwave deicing time; the lower the ambient temperature, the longer microwavedeicing time, the faster the rate of temperature rise junction; the ice thickness has little effecton microwave deicing time, averaging ice thickness increasing0.01m, microwave deicingtime prolonging0.3s. |
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