共查询到18条相似文献,搜索用时 150 毫秒
1.
以生土作为填料,制备了生土泡沫混凝土.试验研究了生土泡沫混凝土的干表观密度、抗压强度、导热系数、孔隙分布和吸湿特性,探讨了微硅粉对生土泡沫混凝土抗压强度和导热系数的影响.结果表明:生土泡沫混凝土干表观密度、抗压强度和导热系数均随着泡沫掺量(体积分数)的增大而减小;随微硅粉掺量(质量分数)增大,生土泡沫混凝土抗压强度和保温隔热性能同时得到改善.利用生土作填料,同时掺加20%微硅粉,可以制备出干表观密度、抗压强度和导热系数分别为790kg/m3,7.8MPa及0.156W/(m·K)的性能优异的生土泡沫混凝土(泡沫掺量为60%).泡沫掺量75%的生土泡沫混凝土(未掺微硅粉)的纳米级孔隙量低,吸湿能力小. 相似文献
2.
以黏土取代石英砂,采用普通硅酸盐水泥、高铝水泥和发泡剂等原材料制备黏土质泡沫混凝土。研究探讨了泡沫掺量和微硅粉掺量对黏土质泡沫混凝土表观密度、28d抗压强度、导热系数以及孔隙结构等物理性能的影响。试验结果表明,泡沫掺量和微硅粉掺量对泡沫混凝土的强度和保温隔热等性能有较大影响,其中泡沫掺量在40%~60%时最为合适。随着泡沫掺量的增大,导热系数不断减小,黏土质泡沫混凝土的表观密度和强度不断降低;随着微硅粉掺量的增大,黏土质泡沫混凝土的强度和保温隔热性能均得到提高。 相似文献
3.
4.
《广东建材》2017,(7)
采用化学发泡方式,以碱激发粉煤灰-偏高岭土基地聚合物为胶凝材料,制备出密度低于400kg/m~3的地聚合物轻质泡沫混凝土。研究了材料组成对地聚合物泡沫混凝土干密度、抗压强度、吸水率及导热系数的影响,并对地聚合物泡沫混凝土的孔结构进行了分析。研究表明:随着水料比增加,地聚合物泡沫混凝土吸水率增大,导热系数降低,平均孔径越小,孔隙率越大;在偏高岭土-粉煤灰激发材料体系中,偏高岭土掺量由40%增加至50%时,地聚合物泡沫混凝土性能没有明显改善;当水玻璃掺量增加时,地聚合物泡沫混凝土干密度和抗压强度增加,吸水率降低。当水料比为0.55、水玻璃掺量50%、偏高岭土掺量40%时,制备的地聚合物泡沫混凝土性能最佳,其干密度、14d抗压强度、吸水率和导热系数分别为366kg/m~3、1.18MPa、30.2%和0.084W/m.K。 相似文献
5.
《四川建材》2018,(12)
采用固体废弃物(粒化高炉矿渣、粉煤灰)、水玻璃、Na OH、发泡剂、页岩陶粒、水制备地聚合物基泡沫混凝土。试验研究了不同配合比地聚合物基泡沫混凝土的干密度、抗压强度、吸水率及导热系数。研究结果表明:(1)当水胶比在0.43~0.53时,地聚合物基泡沫混凝土的干密度、抗压强度和导热系数呈先增大而后减小趋势,而吸水率则先减小后增大;(2)当发泡剂掺量在0.3%~0.8%时,地聚合物基泡沫混凝土的干密度、抗压强度和导热系数不断减小,而吸水率不断增加;(3)当水玻璃模数在1.40~2.24时,地聚合物基泡沫混凝土的干密度、抗压强度和导热系数不断减小,吸水率不断增加。 相似文献
6.
7.
以钢渣和粉煤灰为掺合料的水泥基泡沫混凝土的研制 总被引:4,自引:0,他引:4
研究了钢渣和粉煤灰为掺合料对水泥基泡沫混凝土性能的影响。结果表明:用优质粉煤灰等质量取代水泥。不仅可降低泡沫混凝土的干体积密度和导热系数,而且在同条件下可提高低泡沫混凝土的强度;钢渣粉对泡沫混凝土的干体积密度影响不大。但会降低泡沫混凝土的强度.而钢渣粉与粉煤灰复合取代水泥时可以得到良好的效果:泡沫用量是影响泡沫混凝土的干体积密度、抗压强度和导热系数的主要因素,泡沫量增加会导致泡沫混凝土的密度降低,强度也减小,导热系数减小;泡沫混凝土的导热系数与干体积密度近似呈指数函数关系。 相似文献
8.
9.
10.
采用正交试验分析,研究了粉煤灰掺量、矿渣掺量、水灰比对泡沫混凝土性能的影响关系。试验结果表明,在双掺粉煤灰矿渣泡沫混凝土中,矿渣掺量对泡沫混凝土抗压强度有显著地影响,随着矿渣掺量的增加,泡沫混凝土的抗压强度不断增加,并且导热系数也随之增加。当矿渣掺量为10%时,双掺粉煤灰矿渣泡沫混凝土具有最低的导热系数。 相似文献
11.
S.A. Barbhuiya J.K. Gbagbo M.I. Russell P.A.M. Basheer 《Construction and Building Materials》2009,23(10):3233-3239
This paper presents the results of an experimental investigation on the properties of fly ash concrete incorporating either hydrated lime or silica fume to improve the early strength of concrete. Test results indicated that the addition of lime and silica fume improved the early age compressive strength of fly ash concrete. The inclusion of silica fume was also found to increase the 28 days strength significantly. The air permeability of concrete containing lime and silica fume either decreased or remained almost the same when compared to the concrete without these. The addition of lime and silica fume also improved the sorptivity of concrete.Through the use of differential scanning calorimetry and thermogravimetric analysis (DSC/TG), it was demonstrated that the addition of hydrated lime increased the Ca(OH)2 content; whereas the addition of silica fume decreased the Ca(OH)2 content in the cement paste. The mercury intrusion porosimetry (MIP) data confirmed the beneficial action of hydrated lime and silica fume, towards decreasing the total pore volume of fly ash cement paste. 相似文献
12.
王刚 《混凝土与水泥制品》2021,(2):101-104
研究了稻壳灰、硅灰、稻壳灰+粉煤灰、硅灰+粉煤灰对混凝土抗压强度、抗折强度、抗硫酸侵蚀能力和抗碳化能力的影响.结果表明:掺加5%~10%稻壳灰或硅灰有助于提升混凝土的抗压强度和抗折强度,且稻壳灰、硅灰掺量越高抗压强度越高,掺硅灰混凝土相对于掺稻壳灰混凝土的抗压和抗折强度更高,掺稻壳灰+粉煤灰、硅灰+粉煤灰试件的抗压和抗... 相似文献
13.
研究了2种不同稳泡剂对粉煤灰泡沫混凝土发泡倍数和泡沫稳定时间的影响,结合试验结果探讨了微泡的形成和稳定机理;测试了典型配比粉煤灰泡沫混凝土拌合物稳定性,以及干密度.抗压强度、热导率等物理力学性能指标,为制备高性能无机保温墙材制品提供了技术支撑. 相似文献
14.
15.
M.J. Shannag 《Construction and Building Materials》2011,25(2):658-662
This research investigates the properties of fresh and hardened concretes containing locally available natural lightweight aggregates, and mineral admixtures. Test results indicated that replacing cement in the structural lightweight concrete developed, with 5–15% silica fume on weight basis, caused up to 57% and 14% increase in compressive strength and modulus of elasticity, respectively, compared to mixes without silica fume. But, adding up to 10% fly ash, as partial cement replacement by weight, to the same mixes, caused about 18% decrease in compressive strength, with no change in modulus of elasticity, compared to mixes without fly ash. Adding 10% or more of silica fume, and 5% or more fly ash to lightweight concrete mixes perform better, in terms of strength and stiffness, compared to individual mixes prepared using same contents of either silica fume or fly ash. 相似文献
16.
浅谈影响泡沫混凝土性能的若干因素 总被引:2,自引:0,他引:2
以自制复合型蛋白质为发泡剂.制备泡沫混凝土砌块.研究了泡沫加入量、粉煤灰和石灰石膏对泡沫混凝土性能的影响.研究结果表明:泡沫加入量增加,泡沫混凝土砌块的干密度逐步减小,抗折和抗压强度递减.粉煤灰加入量增加,泡沫混凝土砌块的干密度递增,抗折和抗压强度增大.石灰、石膏最佳加入量分别为粉煤灰加入量的20%和10%. 相似文献
17.
为研究矿物掺合料与增效剂对混凝土力学性能的影响,设计了C30和C40两种强度等级的20个配合比及基准对照组配合比,每个强度等级又设计了3组单掺CTF混凝土增效剂时水泥用量分别减少7%、10%、15%的配合比,复掺时粉煤灰掺量分别为15%、20%、25%,硅灰掺量为6%和9%,CTF混凝土增效剂掺量为10%,通过测试试块在7d、28d、60d的抗压强度,研究其抗压强度随龄期的变化规律。结果表明,CTF混凝土增效剂单掺时水泥减少量为10%~15%的情况下,增效剂的增效效果最明显,且此时CTF混凝土增效剂对混凝土抗压强度也有很大的提高,当粉煤灰、硅灰以及CTF混凝土增效剂复掺时,试块抗压强度值高于基准组试块,此时粉煤灰最佳掺量为20%左右,硅灰掺量为6%左右,且复掺时由于增效剂的作用以及粉煤灰和硅灰的替代,节约了大量的水泥。 相似文献
18.
Osama Ahmed Mohamed Omar Fawwaz Najm 《Frontiers of Structural and Civil Engineering》2017,11(4):406-411
This paper presents the findings of an experimental program seeking to understand the effect of mineral admixtures on fresh and hardened properties of sustainable self-consolidating concrete (SCC) mixes where up to 80% of Portland cement was replaced with fly ash, silica fume, or ground granulated blast furnace slag. Compressive strength of SCC mixes was measured after 3, 7, and 28 days of moist curing. It was concluded in this study that increasing the dosage of fly ash increases concrete flow but also decreases segregation resistance. In addition, for the water-to-cement ratio of 0.36 used in this study, it was observed that the compressive strength decreases compared to control mix after 28 days of curing when cement was partially replaced by 10%, 30%, and 40%of fly ash. However, a fly ash replacement ratio of 20% increased the compressive strength by a small margin compared to the control mix. Replacing cement with silica fume at 5%, 10%, 15%, and 20% was found to increase compressive strength of SCC mixes compared to the control mix. However, the highest 28 day compressive strength of 95.3 MPa occurred with SCC mixes in which 15% of the cement was replaced with silica fume. 相似文献