Analysis of infrared radiation heating wavelength range of asphalt pavement

To determine the optimal band interval for infrared heating of asphalt pavement, the operating conditions of pulse intermittent heating process and the heating distance of 10 cm are set, and the infrared radiation heating mechanism of asphalt pavement and the heat transfer process inside the pavement layer are analyzed. According to the infrared spectrum absorption characteristics of the three main components of SBS modified asphalt, coarse and fine aggregate and water in the asphalt mixture, the infrared absorption peaks of the three materials in the 2-15 μm infrared band are determined. With the aid of finite element analysis software ABAQUS, heating time and energy consumption are used as evaluation indicators. Numerical simulations are carried out for the infrared radiation heating process of 6 typical asphalt pavements under different infrared wavelengths. The results show that with the increase of the wavelength, the heating time of infrared radiation on 6 different grades of asphalt pavement first slowly increases, and then sharply increases; the energy consumed by the infrared radiation heater first decreases rapidly, and then slowly decreases. A comprehensive analysis of the two evaluation indicators of heating time and energy consumption shows that the best band for the in-situ thermal regeneration infrared radiation heating of asphalt pavement is the wavelength of 4. 0-5. 0 μm, and the corresponding heater radiation source temperature is 460-644 °C. It provides a theoretical basis for the subsequent thermal in-situ regeneration of asphalt pavement, infrared radiation heating temperature, energy consumption, heater design, etc. © 2022 Southeast University. All rights reserved.