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第九期

宋安康,宋雪梅,郭 铮,宋 强,姚 洪,岳川淞,冯启明,黄 阳

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摘 要:针对高岭石型硫铁矿选矿尾矿的成分特点,对其用作水泥活性混合材的火山灰活性进行了研究。结果表明,该尾矿经适当温度的煅烧,再粉磨到一定粒度后具有很高的火山灰活性,其活性指数高达120%,是良好的水泥活性混合材和高性能混凝土活性掺合料,其优点主要是生产工艺简单,能耗低、不产生二次污染。 Abstract: Aming the characteristics of kaolinite type pyrite cinder, the research on pozzolanic activity of cement active admixture is carried out.The results show that, tailing is calcined in appropriate temperature then is ground to a certain fineness with high pozzolanic activity, its activity index is up to 120%, the tailing can be used as fine cement active admixture and admixture for high-performance concrete. The advantages are included in simple production process, low energy consumption and high consumption of the tailing without secondary pollution.

别思汗1,张 龙2,王利刚3,吴 玺3

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摘 要:用橡胶粉以20%的比例等体积替换C40混凝土中的砂,制成橡胶混凝土,并添加不同种类的纤维对其进行改性。试验表明,橡胶粉与水泥结合状况较好,橡胶混凝土具有低自重、低弹模,较好的延性及抗裂性能等优点,但强度及流动性降低明显。纤维的掺入能提高橡胶混凝土的强度,同时不降低其延性及抗裂性能。纤维对橡胶混凝土抗折强度的改善效果优于抗压强度及劈裂抗拉强度。钢纤维是改善效果最明显的单掺纤维,塑钢纤维与水泥缺乏足够的黏结力而改善效果不佳。纤维混杂后,在一定范围的掺量呈现正效应。 Abstract: Rubber concrete(RC) is prepared by replace 20% sand of C40 concrete by rubber powder in an equal volume which is adding different kinds of fiber materials to modify the properties of RC. The results show that rubber powder can be well combined with cement, RC has advantage of low self-esteem, low elastic modulus, good ductility and crack resistance, but strength and mobility are reduced significantly. The strength of RC is improved by adding fiber meanwhile, ductility and crack resistance are not reduced. Improvement effects of fiber on flexural strength is better than splitting tensile and compressive strength. Steel fiber is better than any other fiber in improvement effect. Plastic fiber is poor in modifying properties because of its bad combination with cement. Mixing fibers have positive effects in a certain range.

田艳凤1,2,李赞成2,高艳青2

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摘 要:以C30混凝土为基准,选用16目、20目、40 目三种粒径废旧轮胎橡胶粉等体积取代粗细骨料制备橡胶混凝土,研究胶粉粒径、掺量对橡胶混凝土28d后的平均渗水高度、相对渗水系数的影响。结果表明,掺入橡胶粉后,混凝土拌合物流动性减弱,孔隙率减小;16目胶粉混凝土的渗水高度和相对渗透系数随胶粉掺量呈现先低再高再低的变化,20目、40目胶粉橡胶混凝土波动变化小;胶粉掺量小于125L时,三种胶粉制备的混凝土,相对渗透系数均小于基准混凝土,到125L时,相对渗透系数趋于一致;综合橡胶混凝土28d抗压强度和抗渗性能表现,橡胶粉的掺量宜控制在100L以内,最佳粒径为20目和40目。 Abstract: Using C30 concrete as a standard, rubber concrete is prepared by waste scrap rubber powder with three particle size of 16 mesh, 20 mesh and 40 mesh scrapped which is replaced in same volume. The influence of powder particle size and dosage on average water penetration height and relative permeability coefficients for rubber concrete after 28 days later is investigated. The results show that, the fluent of fresh concrete decreases and porosity reduces by adding rubber powder; by adding dosage of powder, water penetration height of concrete with 16 mesh powder and relative permeability coefficients decrease first then increase at last decrease, while 20 mesh and 40 mesh varies between a small range; when dosage of powder is less than 125 liter, relative permeability coefficient of rubber concrete mixed with three kinds of powder is less than reference concrete. Relative permeability coefficient of rubber concrete comes consistent up to 125 liter dosage. Compressive strength and permeability of rubber concrete in 28 day are synthesized, the content of rubber powder is controlled by 100 liter, best diameter is 20 mesh and 40 mesh.

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摘 要:以某实际工程为例,介绍了超厚大体积重混凝土配制过程及施工质量控制要点,可为类似工程提供参考与借鉴。 Abstract: For an actual engineering as a example,the preparation process of super thickness mass concrete and quality control points of construction are introduced, that can provide reference for such engineering.

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摘 要:结合福建省首个全装配式钢筋混凝土框架结构建筑,介绍了装配式混凝土框架结构预制构件的生产及安装施工过程中的关键工艺和技术要点。项目自身结构复杂,构件拆分种类繁多,预制率高,实施过程中在工艺工法方面做了一些改进创新。相对于传统施工,装配式施工技术具有施工速度快、产品质量高、施工现场整洁等优点,符合绿色建筑施工要求。 Abstract: Based on the pilot project of Fujian province's first full prefabricated reinforced concrete frame structure building, this paper detailed introduce the key crafts and main technical points of assembled monolithic concrete frame structure in the process of production and installation. Due to the complicated structurewide variety of protocol component split and high prefabrication ratio, this project had done lots of innovative work in the improvement of crafts and methods.The monolithic precast concrete construction has an advantage in construction speed, high product quality and clean site over traditional construction,satisfied with green building construction requirements.

王忠平1,韩玉春2,韦银华2,夏如茜2

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摘 要:分析了现有砂浆标准中的两种砂浆保水性测试方法,对比了不同砂浆保水增稠材料的测试结果及高保水性特种砂浆的测试结果。结果表明,同样材料下试模滤纸法测试结果偏高,容易达到标准要求,而用真空抽滤法均达不到低保水标准要求。砌筑与抹灰砂浆用真空抽滤法和试模滤纸法测试的砂浆保水率存在明显的差异。而真空抽滤法能有效区分特种砂浆保水性能上的差异。建议预拌砂浆根据不同保水率分级,以便用户可根据基墙吸水的不同选用不同保水性能的砂浆。 Abstract: Two kinds of test method for water retention of mortar are analyzed in existing standards, test results of different water retention and thickending materials of mortar and high water retention of special mortar are compared. The results show that the test results increase with tryout filter paper method under the same materals and tryout filter paper method can meet standard requirments easily, however, vaccum take-off method can meet standard requirments hardly. There are significant differences of mortar retentivity for masonry mortar and mortar for plaster and between vaccum take-off method and tryout filter paper method. Vaccum take-off method can effectively distinguish the differences of water retention properties for special mortar. According to different water retention rate, the grade of ready-mixed mortar is proposed. Based on different absorption of wall, the users can choose different water retention of mortar.