微胶囊相变调温剂调温指标与效果评价研究

发布时间：2018-07-20 17:35

【摘要】：沥青路面在低温环境下产生的路面开裂和路面结霜凝冰，不仅严重影响路面的使用性能与寿命，还会造成严重的交通安全问题，一直是困扰国内外道路工程界的主要问题。已有相关研究主要通过沥青路面低温抗裂性能试验方法与评价指标研究改善沥青混合料的低温稳定性，采用人工、机械、化学、热力等方式实现路面融冰化雪，这些被动应对技术措施虽起到了一定积极作用，但沥青路面低温病害仍普遍出现。项目组前期研究中研制了沥青混合料用微胶囊相变调温剂，提高了沥青混合料应对低温环境的自主调温能力，但对其调温指标与效果的研究尚不全面。本研究利用掺加微胶囊相变调温剂的沥青混合料制作了沥青混合料室外立方体模型，通过对模型在室外实际环境条件下进行实时温度监测与分析，研究模型内部温度场分布和特征温度界面的变化情况，得出了微胶囊相变调温沥青混合料的传热一般规律以及影响其传热性能的外界环境因素。在此基础上，提出潜热积温值和潜热调温指数作为衡量微胶囊相变调温剂潜热调温效果的评价指标，有效表征了调温剂相变潜热调温能力和效率。揭示了潜热作用时间域和温度域对评价指标的交互影响，分析了在不同外界升降温环境下，温度域和时间域的变化对潜热积温值和潜热调温指数的影响，揭示微胶囊相变调温剂在不同相变潜热阶段内的调温机理。基于微胶囊相变调温剂相变潜热过程中时间域与温度域之间的转换关系，提出了调温剂有效发挥相变潜热作用的时间域和温度域范围，，建立了潜热积温值与时间域和温度域的关系式，确定了调温剂有效发挥相变潜热作用的潜热调温指数最低值要求，综合提出了微胶囊相变调温剂潜热调温效果的评价指标要求。
[Abstract]:The cracking and frosting of asphalt pavement in low temperature environment not only seriously affect the pavement performance and service life, but also cause serious traffic safety problems, which has been the main problem of road engineering at home and abroad. The existing research mainly through the asphalt pavement low-temperature crack resistance test method and evaluation index research to improve the asphalt mixture low-temperature stability, using artificial, mechanical, chemical, thermal and other ways to achieve road ice and snow, These passive technical measures have played a positive role, but asphalt pavement low-temperature disease is still widespread. In the previous research of the project group, the microencapsulated phase change temperature-regulating agent for asphalt mixture was developed, which improves the ability of asphalt mixture to adjust temperature independently in low temperature environment, but the research on its temperature regulation index and effect is not comprehensive. In this paper, an outdoor cube model of asphalt mixture is made by adding microencapsulated phase change thermostat, and the real time temperature monitoring and analysis of the model is carried out under the condition of outdoor actual environment. The distribution of temperature field in the model and the change of characteristic temperature interface are studied. The general rules of heat transfer of microencapsulated phase-change and temperature-adjusted asphalt mixture and the external environmental factors affecting its heat transfer performance are obtained. On this basis, the latent heat accumulated temperature value and latent heat regulating index are put forward as the evaluation indexes to evaluate the latent heat regulation effect of microencapsulated phase change thermostats, and the capability and efficiency of latent heat regulation of microencapsulated phase change thermostats are effectively characterized. The interaction of latent heat action time domain and temperature domain on the evaluation index is revealed, and the influence of temperature domain and time domain on latent heat accumulated temperature and latent heat regulation index is analyzed. The temperature regulation mechanism of microencapsulated phase change thermostats in different phase change latent heat stage was revealed. Based on the relationship between time domain and temperature domain in the process of phase change latent heat of microencapsulated phase change thermostats, the time domain and temperature domain range of thermostat to exert the latent heat effect of phase change are put forward. The relationship between latent heat accumulated temperature value and time domain and temperature domain was established. The minimum value of latent heat regulation index was determined, and the evaluation index of latent heat regulation effect of microencapsulated phase change thermostat was put forward.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U414

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