摘 要

温拌沥青混凝土因其低拌和摊铺温度而广受青睐。随着全国沥青混凝土路面的普及，在许多环境恶劣的低气温地区，越来越多的温拌沥青混凝土路面被投入使用，而城市交通荷载量的持续增长，使得沥青路面的疲劳开裂成为城市道路施工中不得不面对的问题。温拌沥青混合料和传统的热拌沥青混合料一样具有自愈合性能，当给予一段间歇期或提高温度，温拌沥青混凝土路面也可以部分或完全修复疲劳裂纹，延长其路面服役寿命。

传统的热拌沥青混合料通过感应加热的方法可以提高自愈合效率。为了研究温拌沥青混合料在感应加热后的愈合效果，本文利用四点弯曲疲劳实验，研究了添加钢纤维的温拌沥青混凝土小梁在感应加热前后的疲劳寿命变化率。研究发现：电磁感应加热有效距离为33mm时，温拌沥青混凝土的升温速率为0.42℃/s，温拌沥青混凝土小梁的最佳愈合温度为75℃，小梁的疲劳寿命恢复率在小加载应变范围内随应变增大而增大，而在大加载应变范围内应变增大而减小，通过比较发现感应加热愈合效率远远优于常温愈合。因此，利用电磁感应加热愈合温拌沥青混凝土路面，可以较大程度的延长路面的服役寿命。本文的研究成果对于利用电磁感应加热实现温拌沥青混合料的自愈合具有重要的指导意义。

关键词:温拌沥青混凝土；感应加热；自愈合；疲劳寿命

Abstract

Warm mix asphalt concrete (WMA) is an advanced technology due to its low mixing and paving temperatures. With the popularity of asphalt concrete pavement in our country, more and more warm mix asphalt concrete pavements are used in some low temperature areas. And nowadays, the urban road construction personnel have to face the problem of asphalt surface damage caused by the continued growth of the urban traffic load. It is found that warm mix asphalt has the self-healing capacity just like the traditional hot mix asphalt. When given a rest period or raising the temperature, warm mix asphalt concrete pavement is able to partially or completely heal the fatigue crack, making it possible to extend the pavement's service life.

The traditional hot mix asphalt mixture can improve its self-healing efficiency through the induction heating method. In order to evaluate the healing capacity of warm mix asphalt mixture through the same heating method, this paper measured the fatigue life extension ratio of warm mix asphalt after induction heating by four point bending fatigue test. It is found that the effectively shortest heating distance is 33mm, specimen heating rate is 0.42 ^oC/s and the best healing temperature of warm mix asphalt concrete is 75 ^oC. In addition, the fatigue life extension ratio of specimen increases with strain in the small strain range, while it decreases with strain in the large strain range. It is clear that healing through the induction heating is much better than healing at normal temperature. Therefore, it is concluded that healing the warm mix asphalt concrete pavement by induction heating can greatly extend the service life of pavement.

Keywords: WMA；Induction heating；Self-healing；Fatigue life

目 录

摘 要 I

Abstract II

第1章 绪论 1

1.1 研究背景及意义 1

1.2 国内外研究现状 2

1.2.1 沥青和沥青胶浆的自愈合研究现状 2

1.2.2 沥青混合料的自愈合研究现状 2

1.2.3 温拌沥青混合料的研究现状 3

1.3 研究内容及技术路线 4

第2章 原材料与实验方法 5

2.1 实验原料 5

2.2 实验方法 6

2.2.1 小梁试件的制备 6

2.2.2 四点弯曲疲劳实验 7

2.2.3评价方法 8

2.2.4 电磁感应加热愈合实验 8

第3章 温拌沥青混合料的最佳愈合温度研究 10

3.1 电磁感应加热实验 10

3.2 感应加热的升温速率 11

3.3最佳愈合温度 12

3.3.1 实验内容 12

3.3.2 实验数据及分析 14

3.3.3 本章小结 15

第4章 应变水平对温拌沥青混合料感应自愈合性能的研究 16

4.1 温拌沥青小梁的疲劳寿命分析 16

4.2 温拌沥青小梁的自愈合分析 18

4.2.1实验内容 18

4.2.2 实验数据 18

4.2.3 本章小结 20

第五章 结论与展望 21

5.1 结论 21

5.2 展望 21

参考文献 22

致 谢 24