保坍增强型混凝土功能型外加剂BTC-3应用性能研究

发布时间：2018-04-12 19:56

本文选题：保坍增强 + 工作性能　；参考：《北京建筑大学》2015年硕士论文

【摘要】：近年来,我国大兴土木,消耗了大量的能源、资源,导致一些地区在近年来出现资源匮乏、原材料质量恶化的问题,这些问题使实际工程应用中的一部分混凝土出现坍落度损失过快、强度不足、耐久性差等问题。实际工程中应对这类问题常见的方法是使用提高减水剂的掺量或复配葡钠等缓凝功能组份,然而减水剂掺量过高容易造成混凝土离析泌水,继续加大缓凝组分掺量并不能增大其缓凝效果,目前在很多实际工程应用中非常需要一种可以改善混凝土工作性,延缓坍落度损失和提高混凝土强度的新型外加剂。本课题研制的具有保坍增强功能的混凝土外加剂BTC-3主要成分为保坍助剂BTC500和增强型功能型外加剂BTC-2,作为外加剂单独掺加使用时不仅能改善混凝土工作性和力学性还可以有效减少混凝土坍落度经时损失,在一些水泥用量偏高的地区使用可以适当的减少一部分水泥用量,混凝土各龄期强度不降低。BTC-3是一种新型的混凝土保坍增强剂,可以显著改善混凝土匀质性,使混凝土工作性能得到明显改善,离析泌水现象减少,有效降低混凝土坍落度经时损失,使混凝土内部更加密实,对高混凝土耐久性有利。试验结果表明:(1)以BTC500替代30%~50%的BTC-2时配制的混凝土强度最好、工作性最佳,坍落度经时损失最小。(2)单独掺加BTC-3,掺量在0~1%范围内递增时,水泥净浆流动度先减小后增大,水泥净浆粘度先增大后减小。(3)使用BTC-3配制的混凝土工作性能得到明显改善,混凝土坍落度经时损失减小。(4)单独掺加BTC-3混凝土28d强度提高2~5MPa,长期强度不倒缩;与水泥适应性能良好,水泥用量偏高的情况下,掺加BTC-3并且降低5%~9%的水泥用量,混凝土各龄期强度不降低,长期强度不倒缩。(5)掺加BTC-3的混凝土内部更加密实,有助于提高凝土耐久性。
[Abstract]:In recent years, our country has built up a large amount of energy and resources, which has led to the shortage of resources and the deterioration of raw material quality in some regions in recent years.These problems make some concrete in practical engineering lose too fast slump, insufficient strength, poor durability and so on.The common way to deal with this kind of problems in practical engineering is to increase the content of water reducer or the retarding function component such as compound sodium gluconate. However, the excessive amount of water reducing agent can easily cause the concrete to separate and bleed.Increasing the content of retarding component can not increase its retarding effect. At present, a new kind of admixture which can improve the workability of concrete, delay the loss of slump and increase the strength of concrete is needed in many practical engineering applications.The main components of concrete admixture BTC-3, which has the function of anti-collapse and strengthening, are BTC500 and BTC-2, which can not only improve the workability and mechanical properties of concrete, but also improve the workability and mechanical properties of concrete.It can also effectively reduce the slump loss of concrete.In some areas where the cement content is too high, the amount of cement can be appropriately reduced, and the strength of concrete at different ages is not reduced. BTC-3 is a new type of concrete strengthening agent, which can significantly improve the homogeneity of concrete.The concrete working performance is improved obviously, the phenomenon of segregation and bleeding is reduced, the slump loss of concrete is effectively reduced, and the concrete interior is more compact, which is beneficial to the durability of high concrete.The test results show that when BTC500 is used instead of 30% BTC-2, the concrete strength is the best, the workability is the best, and the slump loss is the least. The cement paste fluidity decreases first and then increases when the addition of BTC-3 is increased in the range of 0.1%.The cement paste viscosity increased first and then decreased. 3) the concrete working performance of concrete prepared with BTC-3 was obviously improved, and the slump loss of concrete decreased. 4) the 28d strength of concrete mixed with BTC-3 alone increased by 2? 5 MPa, and the long-term strength did not shrink.In the case of good adaptability to cement and high cement content, the concrete added with BTC-3 and reduced by 5% or 9% of the cement content, the strength of concrete at each age does not decrease, and the long-term strength does not shrink. 5) the concrete with BTC-3 is more dense.It is helpful to improve the durability of clay.
【学位授予单位】：北京建筑大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528.042

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