道路水泥混凝土耐久性与微观结构关系及改进技术研究

发布时间：2018-05-21 09:18

本文选题：道路工程 + 水泥混凝土　；参考：《东北林业大学》2015年硕士论文

【摘要】：水泥混凝土路面因其众多优点已被广泛应用,由于路面水泥混凝土长期暴露在自然环境中,使用寿命受自然因素和行车荷载影响,具有良好的耐久性才能保证其在服役期间的服务水平,因此路面水泥混凝土的耐久性问题是目前混凝土材料研究的主要方向之一。决定道路水泥混凝土宏观耐久性能的因素较多,除了受原材料和配合比的影响,前人的研究证明,混凝土硬化后形成的微观结构是影响其耐久性的本质内在因素。本文基于道路水泥混凝土的基本要求,通过变化混凝土配合比中引气剂的剂量,配制了具有不同微观结构的道路水泥混凝土。微观试验主要采用压汞法、光学法和电子显微镜扫描法测试各组道路水泥混凝土微观孔隙结构参数、孔隙结构分布及水泥浆体、界面过渡区域的形貌；宏观试验主要采用快速冻融法和电通量法测试各组道路水泥混凝土抗冻性与抗渗透性能。主要分析了各孔隙结构指标和微观形貌对道路水泥混凝土抗冻性与抗渗透性能的影响规律,并针对黑龙江地区的道路水泥混凝土推荐了各孔隙结构参数的合理取值范围。同时,基于微观层面提出了改善路面水泥混凝凝土微观孔隙结构,进而提高其宏观耐久性能的措施,主要是添加矿物掺合料粉煤灰、纳米SiO2、纳米TiO2和改变水胶比的方式。
[Abstract]:Cement concrete pavement has been widely used because of its many advantages. Due to its long-term exposure to the natural environment, the service life of cement concrete pavement is affected by natural factors and traffic loads. The durability of pavement cement concrete is one of the main research directions of concrete materials. There are many factors determining the macroscopical durability of road cement concrete. Besides the influence of raw materials and mix ratio, previous studies have proved that the microstructure formed after concrete hardening is the essential internal factor affecting the durability of road cement concrete. Based on the basic requirements of road cement concrete, the road cement concrete with different microstructure was prepared by changing the dosage of air entraining agent in the mix ratio of concrete. Mercury injection method, optical method and scanning electron microscope method were used to measure the parameters of pore structure, pore structure distribution, cement paste and the morphology of interface transition area in each group of road cement concrete. The rapid freeze-thaw method and the electric flux method were used to test the frost resistance and permeability of road cement concrete in macroscopical tests. The influence of pore structure index and micro-morphology on frost resistance and permeability resistance of road cement concrete is analyzed, and the reasonable range of pore structure parameters is recommended for road cement concrete in Heilongjiang area. At the same time, based on the micro level, the measures to improve the micro pore structure and improve the macroscopic durability of the cement coagulant are put forward, mainly by adding the mineral admixture fly ash, nano Sio 2, nano TiO2 and changing the water / binder ratio.
【学位授予单位】：东北林业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U414

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