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粉煤灰和矿粉双掺的胶砂和混凝土试验研究 总被引:1,自引:0,他引:1
采用正交试验方法进行胶砂试验,研究粉煤灰和矿粉总掺量、粉煤灰与矿粉比例和水胶比三个影响因素对水泥-粉煤灰-矿粉三元胶凝体系胶砂流动度和强度影响,分析三元胶凝材料体系的水化特点和强度发展规律。并在此基础上配制粉谋灰和矿渣双掺的高性能混凝土,研究表明粉谋灰和矿粉双掺的高性能混凝土早期强度低,后期强度高,混凝土耐久性能好。 相似文献
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选用粉煤灰、矿粉作为掺合料以单掺和复掺的形式掺入到硅酸盐水泥混凝土中,检测其坍落度和3d、28d抗压强度以及早期抗开裂性能。研究结果表明:矿粉、粉煤灰均会降低混凝土3d强度,矿粉可以提高混凝土28d强度,粉煤灰掺量过大会降低混凝土28d强度。随着矿粉掺量的增加,混凝土坍落度随之降低,粉煤灰刚加入时会使混凝土坍落度降低,但是随着掺量的升高,坍落度会逐渐增大;开裂方面:单掺时,粉煤灰与矿粉都在掺量为37%时,抗开裂效果最佳,其中粉煤灰效果最好,复掺时,随着矿粉相对掺量的变大,裂缝的面积和数目都在增大。 相似文献
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粉煤灰、矿粉双掺技术在高性能混凝土中的应用研究 总被引:3,自引:1,他引:3
主要研究了粉煤灰、矿粉双掺技术对高性能混凝土基本性能的影响。通过单掺粉煤灰、单掺矿粉及粉煤灰矿粉双掺技术对混凝土性能的影响比较,得出粉煤灰、矿粉双掺技术对混凝土的影响无论是从拌合物的工作性能,还是从混凝土的力学性能等方面都优于单掺粉煤灰或单掺矿粉的结论。 相似文献
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研究了强度等级(C30和C45)、龄期(28 d和120 d)、矿物掺和料(矿粉和粉煤灰)质量掺量对掺有脂肪族高效减水剂(SAF)的混凝土抗碳化性能的影响,并建立了C30/C45混凝土在28 d/120 d龄期的碳化深度与矿粉/粉煤灰掺量比例之间的回归模型。结果表明:水胶比的降低、养护龄期的延长都能提高水泥石的密实度,从而提高抗压强度和抗碳化性能;混凝土抗碳化性能随矿粉掺量的上升、粉煤灰掺量的下降而提高;当矿粉掺量占胶凝材料质量的37.5%时,C30混凝土的抗碳化性能最佳;当矿粉掺量占胶凝材料质量的31.9%时,C45混凝土的抗碳化性能最佳;当龄期增加时,粉煤灰掺量比例越大则碳化深度的下降幅度越大;矿粉和粉煤灰掺量的相对比例变化时,对低强度混凝土的影响程度要大于高强度混凝土。 相似文献
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为研究双掺超细粉煤灰和矿渣高性能混凝土最优配比,借助室内正交试验的手段测试了不同掺量超细粉煤灰与矿渣对高性能混凝土坍落度、力学及耐久性能的影响.结果表明:复掺超细粉煤灰与矿渣能有效改善混凝土试件的坍落度,随着超细粉煤灰掺量的下降,坍落度有所降低,但降低的幅度很小对高性能混凝土工作性能没有影响;在超细粉煤灰和矿渣总量保持... 相似文献
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为了提高通用聚丙烯的刚性和热变形温度,通过剖析市场上深受用户欢迎的一种进口南韩的高刚性高结晶聚丙烯(PP)的产品,对照茂名石化现有PP产品,找到性能相近的一种PP产品进行改性,改性产品V30K与进口大韩油化均聚HJ4012性能相当,产品V30K顶替进口产品HJ4012顺利进入市场,深受用户好评. 相似文献
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介绍了一种以新型高温混合材料作为铠装热电偶的绝缘材料,通过大量试验验证了封装后的热电偶传感器具有较高的测量精度、长期热电势稳定性、高绝缘性和较短的热响应时间,能够满足高温、高响应性测量要求。在1 000℃的情况下测量,其性能不亚于以氧化镁作为绝缘材料的产品,因此可应用于工业生产和科学研究中。 相似文献
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A variant of the Vienna DMA (Winklmayr et al. 1991; Reischl et al. 1997) with inner and outer electrode radii of 25 and 33 mm, and a conventional trumpet inlet diameter of 97 mm has been tested. It incorporates a reduced pressure drop sheath gas exhaust system that enables reaching flow rates approaching 4000 L/min. Several new additional flow features are included to delay the transition to turbulent conditions. A cylindrical geometry with a DMA length L of 97 mm (distance between the aerosol inlet and outlet slits) is seen to keep the flow laminar up to the highest Reynolds number achieved, though showing slight signs of flow quality deterioration at about Re = 20,000. An equally long DMA with an inner electrode shaped as a 5° cone caped by a spherical dome remains stable up to the highest Reynolds number achieved. It is expected to continue this trend to considerably higher flow rates. Both these long configurations exhibit line widths close to the ideal Brownian diffusion limit, reaching FWHH of 4% for a particle mass diameter of 1 nm. A short DMA with an axial length L of 18 mm and an inner electrode shaped as a 5° cone caped by an ellipse of 3/2 aspect ratio remains also laminar at the highest speeds attained, and exhibits FWHH as small as 2.4%. It departs moderately from ideal behaviour at small flow rates, presumably due to its non-cylindrical geometry. More serious departures observed at high Reynolds numbers may perhaps be due to flow unsteadiness radiated into the working section by sound waves from the turbulent exhaust region. This is the first report of a DMA capable of excellent resolution at 1 nm, yet with a sufficiently wide and long working section to enable (in principle) covering the size range up to 100 nm. 相似文献