密实型沥青混凝土电磁感应加热自修复技术研究

发布时间：2019-05-25 02:21

【摘要】：沥青路面由于在长期的行车荷载和外界环境等作用下,会出现裂缝和松散等不同类型的病害,其路用性能会不同程度地降低,且同时降低沥青路面的服务寿命。现阶段的聚合物材料如防水剂、沥青再生剂等被应用于沥青路面的养护和修复,这些材料会不同程度地影响路面的养护费用和使用性能等。利用沥青结合料本身存在裂缝愈合能力,同时结合沥青的温度敏感性等性能,电磁感应加热技术被应用于沥青路面的养护和裂缝修复上,通过电磁感应加热掺导电材料的沥青混凝土以提高其裂缝愈合性能是现阶段沥青路面修复方法中较先进的技术。本文在AC-13C沥青混凝土中掺加导电材料——钢丝绒,在研究掺钢丝绒沥青混凝土的组成、拌和工艺及其力学性能的基础上,对掺钢丝绒沥青混凝土进行电磁感应加热研究其温度变化情况和裂缝愈合能力。首先,对掺三种不同类型的钢丝绒沥青混凝土进行组成设计,其中试验所用钢丝绒包括3.5mm、6.5mm长2#钢丝绒和3.5mm长4#粉碎型钢丝绒,钢丝绒的掺量包括2%、4%和6%,通过组成和拌和工艺的研究确定了掺钢丝绒沥青混凝土的最佳拌和方式和拌和时间。其次,对掺钢丝绒沥青混凝土进行力学性能测试试验,研究钢丝绒的加入对沥青混凝土带来的影响及影响规律。力学性能试验包括高温、低温及水稳性能等,试验研究表明不同类型和不同含量的钢丝绒对沥青混凝土的力学性能影响程度不同,其中高温和水稳定性能在钢丝绒一定的掺量下表现出提高的作用,低温性能则因钢丝绒的加入表现出负面的影响。然后,通过对掺钢丝绒沥青混凝土马歇尔试件和小梁试件进行感应加热效率测试,研究试件在感应加热条件下的温度分布、变化情况,包括试件的温度梯度和温度升高、降低的速率;在确定感应加热的速率后,将小梁试件在加热至50℃、60℃、75℃和90℃四种温度下,对试件进行三点弯曲试验,研究沥青混凝土感应加热的愈合性能,试验表明感应加热会不同程度地提高掺钢丝绒沥青混凝土的愈合性能。最后,结合掺钢丝绒沥青混凝土的力学性能和感应加热自愈合性能,对沥青混凝土中所掺钢丝绒进行优化设计,并提出最佳的钢丝绒类型和掺量。
[Abstract]:Due to the long-term driving load and external environment, asphalt pavement will appear cracks and loose and other different types of diseases, its road performance will be reduced to varying degrees, and at the same time reduce the service life of asphalt pavement. At present, polymer materials such as water repellent, asphalt regeneration agent and so on are used in the maintenance and repair of asphalt pavement, which will affect the maintenance cost and performance of pavement to varying degrees. Based on the crack healing ability of asphalt binder and the temperature sensitivity of asphalt, electromagnetic induction heating technology is applied to the maintenance and crack repair of asphalt pavement. In order to improve the crack healing performance of asphalt concrete mixed with conductive material by electromagnetic induction heating is an advanced technology in the repair method of asphalt pavement at present. In this paper, steel velvet, a conductive material, is added to AC-13C asphalt concrete, and the composition, mixing process and mechanical properties of steel velvet asphalt concrete are studied. The temperature change and crack healing ability of steel velvet asphalt concrete were studied by electromagnetic induction heating. First of all, the composition design of three different types of steel velvet asphalt concrete is carried out, in which the steel velvet used in the test includes 3.5mm, 6.5mm long 2# steel velvet and 3.5mm long 4# comminuted steel velvet, and the content of steel velvet includes 2%. 4% and 6%. The optimum mixing method and mixing time of steel velvet asphalt concrete were determined by the study of composition and mixing process. Secondly, the mechanical properties of steel velvet asphalt concrete are tested, and the influence and law of steel velvet addition on asphalt concrete are studied. The mechanical properties tests include high temperature, low temperature and water stability. The experimental results show that different types and contents of steel velvet have different effects on the mechanical properties of asphalt concrete. Among them, the high temperature and water stability show the effect of improving the steel velvet at a certain content, while the low temperature performance is negatively affected by the addition of steel velvet. Then, the temperature distribution and variation of the specimen under the condition of induction heating, including the temperature gradient and temperature increase of the specimen, are studied by testing the induction heating efficiency of the steel velvet asphalt concrete Marshall specimen and the beam specimen. The rate of decrease; After determining the rate of induction heating, the three-point bending test of the specimen was carried out at 50 鈩，

本文编号：2485407