Numerical simulation analysis on multi-layer low-temperature heating method of asphalt pavement in hot in-place recycling  

沥青路面就地热再生多层低温加热方法的数值仿真

作　　者：MA Deng-cheng LAN Fen 马登成;兰芬(National Engineering Laboratory for Road Maintenance Equipment,Chang’an University,Xi’an 710064,China;Xi’an Municipal Facilities Management Center,Xi’an 710016,China)

机构地区：[1]National Engineering Laboratory for Road Maintenance Equipment,Chang’an University,Xi’an 710064,China [2]Xi’an Municipal Facilities Management Center,Xi’an 710016,China

出　　处：《Journal of Central South University》2020年第12期3793-3806,共14页中南大学学报（英文版）

基　　金：Project(2017JM5077)supported by the Natural Science Basic Research Plan in Shaanxi Province,China;Projects(300102259109,300102259306)supported by the Fundamental Research Funds for the Central Universities,China。

摘　　要：Asphalt mixture pavement reheating is one of the important steps in hot in-place recycling(HIR).To improve the heating speed of asphalt pavement in HIR,based on the numerical analysis model of asphalt mixture heating process,a new multi-layer low-temperature heating method(MLHM)was proposed.Considering input heat flux,the thermal capacity and thermal resistance of asphalt mixture,the heat transfer model was established based on energy conservation law.By heating the asphalt mixture in layers,it changes the situation that the heat energy can only be input from the upper surface of the asphalt mixture pavement.Through the simulation of the heating method of asphalt mixture in the existing technology,the result shows that the existing heating methods lead to serious aging or charring of the asphalt mixture.By MLHM,the upper and the bottom of the asphalt mixture are heated at the same time,and the heating temperature is lower than other heat methods,which not only reduces the heating thickness and increases the heating area of the asphalt mixture pavement,but also improves the heating speed,saves the energy resource and ensures the heating quality.Especially,by MLHM,the heating uniformity is better and speed is faster.沥青路面就地热再生中对沥青路面铣刨后的料垄进行二次加热是施工中的重要步骤之一。为了提高就地热再生中沥青路面回收材料的二次加热速度,基于沥青混合料加热过程的数值分析模型,提出一种新的多层低温加热方法,并对其进行加热机理分析。在考虑输入热流量、沥青混合料的比热和热阻基础上,根据能量守恒定律建立沥青路面回收材料的传热模型,并进行数值仿真与对比分析。结果表明:通过分层加热沥青路面回收材料铺层,改变了现有加热方法中热能只能从其上表面输入的情况;现有的加热方法会导致沥青混合料铺层严重老化或炭化。多层低温加热方法可以同时对沥青混合料铺层上下表面进行加热,由于采取了分层、低温加热,不仅减小了加热厚度,增加了沥青混合料铺层的加热面积,而且加热温度低于其他加热方式的,因此提高了加热速度,节省了能源,保证了加热质量。与其他加热方法相比,多层低温加热方法表现出了更好的加热均匀性和加热效率。

关 键 词：asphalt pavement hot in-place recycling heating speed heating uniformity MULTI-LAYER LOW-TEMPERATURE 

分 类 号：U416.217[交通运输工程—道路与铁道工程] U418.6