【摘要】 根据道路养护车辆作业时路面材料就地再生利用的工艺特点,探讨沥青混合料再生过程中的加热工艺和加热温度的选择。基于混合料中各种成分的红外光谱分析数据得出了其在1~15μm的远红外波段范围内具有较好的热吸收特性,而沥青混合料材料组成中的沥青和水的热吸收峰值波长范围相近,其平均值范围为3.5~4.0μm。由混合料受热过程的热平衡方程得到混合料加热时其中沥青和水的加热为主要的耗热因素,特别是由于沥青混合料的使用温度为160℃以上,明显超过了水分的沸点,其再生成品料中的水分必须在加热过程中以气体的形式向外蒸发,由此提出了沥青混合料加热过程中预热-汽化-升温的3阶段,其中用于水分蒸发的汽化阶段耗热较大,而混合料中各种级配矿料的加热过程相对耗热较小。基于材料光谱和能耗方程分析的结论,并将相关数据代入维恩-葛利琴位移定律(Wien displacement law)得到沥青混合料的加热温度为450~550℃。根据这些分析设计研发了热风循环加热系统以实现上述目的,并作为道路养护车完成沥青路面材料就地再生利用过程中材料加热的工艺手段,亦对其工程实施效果进行了总结。更多还原

【Abstract】 The selection of heating process and temperature in the recycling process of asphalt mixture is discussed according to the technological characteristics of in-place recycling of pavement materials during working of road maintenance vehicle. It is concluded from the data by infrared spectrum analysis on various ingredients in the mixture that better heat absorption characteristics could be available within the scope of farinfrared band of 1-15 μm,while the wavelength range of heat absorption peak for asphalt and water in the asphalt mixture is similar,whose average value is 3. 5-4. 0 μm. Through the heat balance equation during mixture heating,it is found that the heating of water and asphalt is the main heat consumption factor,especially the operating temperature of asphalt mixture is higher than 160 ℃,which obviously exceeded the water boiling point,and the water in the recycled materials must evaporate outwardly in the form of gas during heating,thus the phases of preheating,vaporization and warming-up during asphalt mixture heating are put forward. Among them,the vaporization phase used for water evaporation has the largest heating consumption,while the heating consumption during heating of various graded mineral aggregates in the mixture is relativelysmall. Based on the conclusion from material spectrum and energy consumption equation analysis,and substituting the related data into Wien displacement law,it is concluded that the heating temperature of asphalt mixture is 450-550 ℃. The heated air circulation heating system is designed and developed based on these analyses to achieve the above goals,which is taken as the technological means for material heating during in-place recycling of asphalt pavement materials by road maintenance vehicle as well. In addition,summarization is also made on the project implementation effect.更多还原