玄武岩纤维沥青混合料增强机理及路用性能研究

发布时间：2018-02-14 23:05

本文关键词： 沥青混合料玄武岩纤维最佳沥青用量增强机理路用性能　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着我国交通事业的飞速发展,交通量的急剧增加,受限于路面材料性能低下以及养护不及时等综合因素,沥青路面在服役期间出现了大量的早期病害。掺入纤维已经成为了综合改善沥青混合料各项性能的重要途径之一,从微观上看来,玄武岩纤维的掺入对沥青的性质起到了改善的作用;从宏观上看来,玄武岩纤维的掺入对沥青混凝土的整体力学性能起到了明显的改善作用。目前,我国在纤维加强沥青混凝土性能方面的研究还处于探索阶段,对于符合我国道路工程建设实际情况的具体纤维种类以及完整的设计方法体系还未建立起来,而国外生产的纤维造价昂贵,大大增加了建设投资成本,考虑到生产玄武岩纤维的主要材料即玄武岩在我国分布广泛,储量丰富,所生产出的玄武岩纤维完全可以满足道路建设的需要,因此,采用在沥青混合料中掺加玄武岩纤维的方法来改善沥青混合料的路用性能,以期避免沥青路面的早期损害,论文开展了以下的研究工作:(1)通过引入复合材料理论和界面化学理论对纤维增强沥青混合料的机理进行分析,阐述纤维的吸附、稳定、加筋、增粘、阻裂、增韧以及增加自愈能力作用,探讨采用纤维增强沥青混合料各项性能的可行性。(2)选取玄武岩纤维、聚酯纤维和木质素纤维进行对比分析,考查三种纤维的力学性能、热稳定性、吸湿性以及吸油性,结果表明,玄武岩纤维的吸湿率最小,力学性能和热稳定性优于聚酯纤维和木质素纤维。(3)将三种纤维以不同掺量掺加到沥青当中,进行沥青三大指标试验、弯曲梁流变试验和动态剪切试验,探讨纤维沥青胶浆的各项性能,试验结果表明,纤维掺入以后,沥青胶浆的高温性能有明显改善,但低温性能却有所降低。综合三种沥青胶浆性能试验结果来看,玄武岩纤维相较于聚酯纤维和木质素纤维是最理想的选择。(4)以AC-13作为玄武岩纤维沥青混合料级配并进行配合比设计,确定不同玄武岩纤维掺量沥青混合料的最佳沥青用量,并在此基础上进行马歇尔试验,探讨沥青混合料各项马歇尔指标的变化情况,试验结果表明,纤维掺量每增加0.1%,沥青混合料的最佳沥青用量约增加0.05%,随着纤维掺量的增加,沥青混合料的毛体积密度、马歇尔稳定度、空隙率和矿料间隙率都逐渐增加,流值离散性变化,马歇尔稳定度在玄武岩纤维掺量为0.4%时达到最大。(5)对不同玄武岩纤维掺量的沥青混合料进行高温车辙试验、低温小梁弯曲试验、以及冻融劈裂试验等一系列路用性能常规试验,考查纤维的掺入对沥青混合料各项路用性能的改善情况并在此基础上确定纤维的最佳掺量。结果表明,玄武岩纤维掺入以后沥青混合料的一系列路用性能指标不同程度的增大,沥青混合料的高温稳定性、低温抗裂性以及水稳定性得以改善,基于AC-13沥青混合料路用性能试验结果的玄武岩纤维最佳掺量为0.4%。
[Abstract]:With the rapid development of China's transportation industry and the rapid increase of traffic volume, it is limited by the low performance of pavement materials and the lack of timely maintenance and other comprehensive factors. Asphalt pavement has a large number of early diseases in service. Blending fiber has become one of the important ways to comprehensively improve the performance of asphalt mixture, from the microscopic point of view, The addition of basalt fiber can improve the properties of asphalt, and from the macro point of view, the mixing of basalt fiber can obviously improve the overall mechanical properties of asphalt concrete. The research on the performance of fiber reinforced asphalt concrete in our country is still in the exploratory stage. The concrete fiber types and the complete design method system which accord with the actual situation of road engineering construction in our country have not been established. The cost of the fibers produced abroad is expensive, which greatly increases the cost of construction investment. Considering that basalt, the main material for producing basalt fibers, is widely distributed and has abundant reserves in China, The basalt fiber produced can completely meet the needs of road construction. Therefore, adding basalt fiber to asphalt mixture is used to improve the pavement performance of asphalt mixture, in order to avoid the early damage of asphalt pavement. The following research work is carried out in this paper: (1) the mechanism of fiber reinforced asphalt mixture is analyzed by introducing composite material theory and interface chemistry theory, and the adsorption, stabilization, reinforcement, viscosity increase and crack resistance of fiber are expounded. The feasibility of using fiber reinforced asphalt mixture to select basalt fiber, polyester fiber and lignin fiber is discussed. The mechanical properties and thermal stability of the three kinds of fibers are examined. The results show that basalt fiber has the smallest moisture absorption rate, better mechanical properties and thermal stability than polyester fiber and lignin fiber. The rheological test and dynamic shear test of bending beam were used to study the properties of fiber asphalt mortar. The experimental results showed that the high temperature properties of asphalt mortar were obviously improved after the addition of fiber. However, the low temperature performance of the three kinds of asphalt pastes has been reduced, and the results of the tests on the properties of three kinds of asphalt pastes show that. Compared with polyester fiber and lignin fiber, basalt fiber is the most ideal choice. AC-13 is used as the gradation and proportion design of basalt fiber asphalt mixture, and the optimum asphalt content of different basalt fiber admixture is determined. On this basis, Marshall test is carried out to discuss the change of Marshall index of asphalt mixture. The results show that the optimum asphalt content of asphalt mixture increases about 0.05 with the increase of fiber content, and with the increase of fiber content, the optimum asphalt content of asphalt mixture increases by 0.05. The bulk density, Marshall stability, void ratio and aggregate clearance rate of asphalt mixture are all increasing gradually, and the flow value is discrete. Marshall stability reaches maximum when basalt fiber content is 0.4.) A series of conventional road performance tests, such as high-temperature rutting test, low-temperature trabecular bending test, freeze-thaw splitting test and so on, are carried out on asphalt mixture with different basalt fiber content. This paper examines the improvement of the road performance of asphalt mixture by fiber blending and determines the optimum fiber content on this basis. The results show that a series of road performance indexes of asphalt mixture increase in varying degrees after the addition of basalt fiber. The high temperature stability, low temperature crack resistance and water stability of asphalt mixture are improved. The optimum content of basalt fiber based on AC-13 asphalt mixture road performance test results is 0.4.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U414

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