碳纤维-水泥乳化沥青砂浆加热带设计与微波除冰功能研究

发布时间：2019-02-22 17:28

【摘要】：本研究提出在沥青混凝土路面构造内部，根据对渠化交通条件下，车辆行驶的轮迹带分布规律，在行车道中轴线对称的两条各0.5m宽的路面上，铺设两条尺寸为50cm×100cm×10cm，顶面弧度为5°~10°的碳纤维-水泥乳化沥青砂浆路板，形成具有微波辐射下融冰化雪功能的加热带，另一方面，对加热带与既有道路及新建道路的组合形式提出设想，采用以玄武岩为集料的水泥乳化沥青混合料作为路板与路面中面层间的绝热层，厚度30~50mm。综述了促进碳纤维均匀分散以及三种评价分散性的方法，提出CT断层扫描技术表征加热带中短碳纤维分散性，借助软件Image pro plus8.0对其进行图像预处理、特征区域识别、特征区域提取与计算等，给出了一整套定量评价分散性的计算公式。同时，利用软件MIMICS对CT图像进行三维重建，并根据重建模型进行有限元分析，结果表明：碳纤维束团会引起束团区域的应力集中，导致该区域在临界荷载下首先破坏，从而引起裂缝的扩张。采用弯拉强度与韧性指数为评价指标，研究了碳纤维用量、碳纤维表面处理工艺、碳纤维长度等因素与复合材料力学性能之间的关系，解析了其变化规律，给出了影响机理，结果表明：碳纤维经过常温硝酸、硝酸水浴和混酸水浴表面处理后，极限弯拉强度和跨中位移明显提高，其中经过混酸水浴后，其增幅分别达到了42.2%和87.5%。碳纤维体积用量Vcf=0.6~1.0%、长度为1~10mm作为加热带使用的碳纤维参数，可作为实际应用中的参考值。给出了冰层与路面的冻黏界面模型，提出以微波照射下试件生热速率的计算公式，研究了碳纤维用量与乳化沥青用量对微波生热速率的影响，并深入分析其影响机理，结果表明：Vcf=0.4%~1.0%时，照射时间30s内，微波生热速率最佳，，其中Vcf=0.6%的关键生热速率k0最佳。在AE/C=5%与AE/C=10%用量下生热速率维持在较高水平，分别为504.4J/s、478.1J/s。实验室研究与计算机模拟技术共同表明其除冰效果较为理想。
[Abstract]:In this paper, it is put forward that in the interior of asphalt concrete pavement structure, according to the distribution law of wheel track band of vehicle running under the condition of channelized traffic, two 50cm 脳 100cm 脳 10 cms are laid on two symmetrical road surfaces with symmetrical axis in the middle of the carriageway. Carbon fiber cement emulsified asphalt mortar pavement with top radians of 5 掳~ 10 掳forms a heating zone with the function of melting snow and ice under microwave radiation. On the other hand, the combination of heating belt with existing roads and new roads is proposed. The cement emulsified asphalt mixture with basalt as aggregate is used as the insulation layer between the road slab and the middle surface of the pavement with a thickness of 30 ~ 50mm. In this paper, three methods to promote the uniform dispersion of carbon fiber and three methods to evaluate the dispersion of carbon fiber are reviewed. CT tomography technique is proposed to characterize the dispersion of short carbon fiber in heating tape. The image preprocessing and feature region recognition are carried out with the help of software Image pro plus8.0. In this paper, a set of formulas for quantitative evaluation of dispersion are given, such as extraction and calculation of feature regions. At the same time, the 3D reconstruction of CT image is carried out by software MIMICS, and the finite element analysis is carried out according to the reconstruction model. The results show that the stress concentration in the area of the bundle is caused by the carbon fiber bundle, which leads to the first failure of the area under critical load. Thus causing the crack to expand. The relationship between the amount of carbon fiber, the surface treatment process of carbon fiber, the length of carbon fiber and the mechanical properties of the composite is studied by using the flexural strength and toughness index as the evaluation index. The variation law of the composite is analyzed, and the influencing mechanism is given. The results show that the ultimate flexural tensile strength and mid-span displacement of carbon fiber treated with nitric acid at room temperature, nitric acid bath and mixed acid bath increase obviously, and the increase of carbon fiber after mixed acid bath reaches 42.2% and 87.5% respectively. Carbon fiber volume Vcf=0.6~1.0%, length of 1~10mm as the heating band used as the carbon fiber parameters can be used as a reference value in practical applications. The model of freezing interface between ice layer and road surface is given. The formula of heat generation rate under microwave irradiation is put forward. The influence of carbon fiber content and emulsified asphalt content on microwave heat generation rate is studied, and the influence mechanism is analyzed. The results showed that when Vcf=0.4%~ was 1.0 and irradiation time was 30 s, microwave heat generation rate was the best, among which Vcf=0.6% critical heat generation rate K0 was the best. The heat generation rate was maintained at a higher level under the dosage of AE/C=5% and AE/C=10%, which were 504.4 J / s ~ (-1) J / s ~ (478.1) J / s, respectively. The results of laboratory research and computer simulation show that the deicing effect is ideal.
【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;U416.2

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