加热方式对RAP热再生混合料中新旧沥青融合效果的影响分析

Analysis of Influence of Heating Methods on Fusion Effect of Old and New Asphalt in RAP Thermally Recycled Mixture

随着旧沥青混合料(RAP)再生技术的不断发展,再生沥青混合料得到越来越多的关注。新旧沥青的融合效果是影响再生沥青混合料的一个重要因素。与传统烘箱的热传导和热辐射等加热方式相比,微波诱导加热通过构建电磁场和分子间振动摩擦作用加热,具有快速、均匀且易控等特点,能够有效促进旧沥青的激活,提高新旧沥青之间的融合。文章从微观角度采用红外光谱法测得微波加热和烘箱加热这两种加热方式作用下的60%RAP掺量再生料的红外光谱图,通过分析光谱图各吸收峰的吸光度大小与位置变化,计算羰基与亚砜基官能团指数,对比加热方式对RAP热再生混合料中新旧沥青的融合程度的影响。试验结果表明:微波加热较烘箱加热更有助于RAP料吸附旧沥青,能够更好地促进新旧沥青的融合。

With the continuous development of Reclaimed Asphalt Pavement( RAP) recycling technology, Reclaimed Asphalt Pavement has received more and more attention.The fusion effect of old and new asphalt is an important factor affecting the Reclaimed Asphalt Pavement. Compared with the traditional oven heating methods such as heat conduction and heat radiation, microwave-induced heating is heated by constructing electromagnetic fields and intermolecular vibration friction, which is fast, uniform and easy to control. It can effectively promote the activation of old asphalt and improve the integration between old and new asphalt. In this paper, the infrared spectrum of recycled materials with 60% RAP content under the action of microwave heating and oven heating is measured by infrared spectrometry from a microscopic point of view. By analyzing the absorbance size and position changes of each absorption peak in the spectrum, the carbonyl and sulfoxide functional group indexes are calculated, and the influence of heating methods on the fusion degree of old and new asphalt in RAP thermally recycled mixture is compared. The test results show that microwave heating is more conducive to the adsorption of old asphalt by RAP materials than oven heating, and can better promote the fusion of old and new asphalt.