玄武岩纤维混凝土的力学性能和耐久性能研究

发布时间：2018-05-28 04:32

本文选题：玄武岩纤维 + 混凝土　；参考：《重庆交通大学》2015年硕士论文

【摘要】：玄武岩纤维有着优越的力学性能,并具有耐高温、耐酸碱、价格低廉、取材便利以及生产过程环保等优点,逐渐成为混凝土增强领域的新兴材料,玄武岩纤维增强混凝土的研究也受到越来越多的关注。本文主要针对玄武岩纤维增强混凝土的力学性能和耐久性能进行了试验研究和微观检测分析,并得出下列结论:①研究了不同体积分数的(0.05%、0.10%、0.15%、0.20%、0.25%、0.30%、0.35%)玄武岩纤维对混凝土的工作性能和力学性能的影响,并结合微观结构检测分析了玄武岩纤维对混凝土增强、阻裂和增韧的作用机理。结果表明,适量的玄武岩纤维掺入混凝土后,混凝土的工作性能有一定的降低,但抗压强度、劈裂抗拉强度和抗弯强度均有不同程度的提高,并且混凝土的韧性得到显著增强。②研究了不同质量分数的(5%、10%、15%、20%、25%、30%)粉煤灰、矿粉分别与玄武岩纤维复合对混凝土的工作性能和力学性能的影响。结果表明,矿物掺合料的掺入对玄武岩纤维增强混凝土的工作性能以及28d抗压强度均有显著的改善与增强效果,但降低了玄武岩纤维增强混凝土的劈裂抗拉强度、抗弯强度以及韧性。③通过相对渗透法和孔结构检测从宏观和微观两方面研究了玄武岩纤维掺量对混凝土抗渗性能的影响,并探讨了玄武岩纤维改善混凝土抗渗性能的作用机理。研究结果表明:当玄武岩纤维体积分数从0.05%增加到0.10%时,混凝土的抗渗性能得到改善;而当玄武岩纤维体积分数大于0.20%时,混凝土中的黏结界面迅速增加,且混凝土中累计孔体积也迅速增大,过多的薄弱界面极易形成裂缝源,从而降低了混凝土的抗渗性能。④当玄武岩纤维体积分数为0.05%~0.15%时,经5%的Na2SO4溶液侵蚀60d后,混凝土抗压强度侵蚀系数基本保持在1左右。但随着纤维掺量的进一步增加,混凝土抗压强度侵蚀系数呈现出下滑态势。当混凝土中掺入0.05%~0.25%体积分数的玄武岩纤维时,虽然混凝土劈裂抗拉强度侵蚀系数小于1,但玄武岩纤维的掺入延缓了混凝土劈裂抗拉强度的损失速度,混凝土抗硫酸盐侵蚀作用得到加强。
[Abstract]:Basalt fiber, with its excellent mechanical properties, high temperature resistance, acid and alkali resistance, low price, convenient material selection and environmental protection in the production process, has gradually become a new material in the field of concrete reinforcement. More and more attention has been paid to the study of basalt fiber reinforced concrete. In this paper, the mechanical properties and durability of basalt fiber reinforced concrete are studied experimentally and microscopically. And the following conclusions are drawn: 1 the influence of basalt fibers on the working and mechanical properties of concrete is studied in different volume fractions of 0.05 and 0.100.10 and 0.15 and 0.20, 0.25, 0.30 and 0.35, respectively, and the reinforcement of concrete by basalt fibers is analyzed by means of microstructural testing. The mechanism of crack resistance and toughening. The results show that when basalt fiber is mixed with concrete, the working performance of concrete decreases, but the compressive strength, splitting tensile strength and flexural strength are improved to some extent. Moreover, the toughness of concrete has been significantly enhanced .2 the effects of different mass fraction of 101010 and 101010 and 20% of different mass fraction on the working and mechanical properties of concrete are studied. The effects of fly ash, mineral powder and basalt fiber on the working performance and mechanical properties of concrete are studied respectively, and the effect of fly ash, mineral powder and basalt fiber on the performance and mechanical properties of concrete is studied. The results show that the addition of mineral admixtures can significantly improve the working performance and 28d compressive strength of basalt fiber reinforced concrete, but decrease the splitting tensile strength of basalt fiber reinforced concrete. The influence of the content of basalt fiber on the impermeability of concrete was studied from macroscopic and microcosmic aspects by relative permeation method and pore structure measurement of flexural strength and toughness. The mechanism of improving the impermeability of concrete by basalt fiber is discussed. The results show that when the volume fraction of basalt fiber is increased from 0.05% to 0.10%, the impermeability of concrete is improved, but when the volume fraction of basalt fiber is greater than 0.20, the bonding interface in concrete increases rapidly. And the accumulative pore volume in concrete also increases rapidly, too much weak interface easily forms the crack source, thus reduces the impermeability of concrete. 4. When the volume fraction of basalt fiber is 0.05-0.15, the concrete is corroded by 5% Na2SO4 solution for 60 days. The compressive strength erosion coefficient of concrete is about 1. However, with the further increase of fiber content, the compressive strength erosion coefficient of concrete shows a downward trend. When 0. 05% basalt fiber is added into concrete, although the concrete splitting tensile strength erosion coefficient is less than 1, the loss rate of concrete splitting tensile strength is delayed by the addition of basalt fiber. The resistance of concrete to sulfate erosion is strengthened.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528

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