【作者】 王勤学；

【导师】 高丹盈；

【作者基本信息】 郑州大学 ， 水工结构工程， 2009， 硕士

【摘要】 纤维混凝土是一种新型的复合材料。与普通混凝土相比,纤维混凝土的抗拉强度、抗弯强度及耐磨、耐冲击、耐疲劳、韧性、抗裂、抗爆性都有所提高,已广泛应用于许多工程领域。矿渣微粉作为一种“绿色建材”,具有价廉、量大的特点,等量取代纤维混凝土中的水泥,变废为宝,降低了纤维混凝土造价,符合可持续发展的要求。本文用矿渣微粉等量取代素混凝土和纤维混凝土中的水泥,配制成了矿渣微粉混凝土和纤维矿渣微粉混凝土,并围绕矿渣微粉混凝土和纤维矿渣微粉混凝土的力学性能展开研究,主要内容如下:(1)分析了国内外有关纤维混凝土的研究现状、工程应用情况以及纤维混凝土的增强阻裂机理,总结了矿渣微粉在水泥和混凝土中的研究和应用情况。(2)通过试验,测定了矿渣微粉混凝土和纤维矿渣微粉混凝土的抗压强度、劈拉强度、抗折强度、弹性模量以及劈拉荷载—横向变形关系曲线和弯曲荷载—挠度关系曲线,探讨了纤维掺量、矿渣微粉掺量和混凝土基体强度等级对上述力学性能的影响,建立了抗压强度随龄期变化的计算模型,统计了抗压和劈拉标准试件和非标准试件之间的强度换算系数。研究表明,矿渣微粉的加入提高了普通混凝土和纤维混凝土的各项力学性能指标;钢纤维对矿渣微粉混凝土的增强增韧效果比较显著,使矿渣微粉混凝土的劈拉荷载—横向变形关系曲线和弯曲荷载—挠度关系曲线更加饱满;聚丙烯纤维也能起到一定的的增强增韧效果,但效果没钢纤维显著。(3)试验表明,矿渣微粉混凝土的抗压试件破坏呈明显的倒锥形并伴随强烈的崩裂声,劈拉破坏试件被劈成两半;纤维矿渣微粉混凝土抗压破坏试件只是表面起皮掉渣,劈拉试件破坏后还保持一个整体,不会裂成两半,并伴有嘈杂的纤维拔断和拔出的声音。更多还原

【Abstract】 Fiber reinforced concrete is a kind of new composite material. As compared with normal concrete, tensile strength, flexural strength, wear resistance, impact resistance, fatigue-resistant, toughness, crack-resistant and antiknock properties are all improved. It is widely used in various fields. As a kind of green building material, slag powder has the features of popular price and large amounts. Equivalent to replace cement within fiber reinforced concrete, we can make full use of resources, and reduce fiber reinforced concrete cost and conformance to requirements of the opinion of sustained development.In this paper, cement witch in normal concrete and fiber reinforced concrete, replaced by slag powder in equal quantity, makes up slag concrete and fiber reinforced slag concrete. Meanwhile, mechanical properties of concrete are studied here. The primary coverage as follows:(1) Retrospective analysis has been done on research situation and project application of fiber reinforced concrete at home and abroad in recent years. Analysising the reinforced and crack-resistanced mechanism of fiber reinforced concrete. Summary the current status of development and application of slag powder in cement and concrete in recent years.(2) The compressive strength, splitting strength, breaking strength, elastic modulus , the relationship curves between splitting load and lateral deformation, and the relationship curves between bending load and deflection of slag concrete and fiber reinforced slag concrete have been tested through experiments. Investigated the effect of fiber content, slag powder content and concrete grade on the above mechanical properties. Established the calculation model for the compressive strength changing by ages. Statisticsed of the conversion factor of compressive strength and splitting strength between standard specimen and non-standard specimen. The results showed that: the index of mechanical properties of normal concrete and fiber reinforced concrete improved after added slag powder; Steel fiber is very efficacious for increasing strength and toughness of concrete; Meanwhile, polypropylene fibre also has effect on increasing strength and toughness, but show worse effect than steel fiber. All the above features can be seen from the relationship curves between splitting strength and lateral deformation, and the relationship curves between bending load and deflection.(3) The compression fracture morphology of slag concrete specimens show distinctly inverted cone accompanied by a strong voice breaking split in half observed through the experiment,while the fracture morphology of fiber reinforced slag concrete specimens show only peeling and dropped residue.And keep an integral whole after added steel fiber for splitting damage specimens, and accompanied by the noise of fiber extracted and broked.更多还原