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脂肪族磺酸盐高效减水剂性能与应用研究 总被引:7,自引:0,他引:7
脂肪族磺酸盐高效减水剂,减水率高,强度增长快,生产工艺简单,对环境无污染。脂肪族磺酸盐高效减水剂的减水分散效果优于传统的萘系高效减水剂,与水泥的适应能力强,可用于制备各种强度等级的泵送混凝土、高强混凝土和自密实免振混凝土。 相似文献
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脂肪族高效减水剂对水泥水化的微观作用机理 总被引:2,自引:0,他引:2
通过运用现代测试分析方法(RD、XRD,SEM、TG-DTA)研究了脂肪族高效减水剂对水泥水化和水泥微观结构的影响.结果分析表明,脂肪族高效减水剂能够显著有效降低水泥硬化过程中的孔隙率和孔径,改善孔的结构分布,在加入SAF减水剂1d水泥初期水化速度较慢,28d以后加入脂肪族减水剂的水泥熟料的水化程度与不加脂肪族减水剂的水泥熟料的水化程度逐渐相同.28d掺加SAF减水剂的水泥石SEM显示内部结构均匀致密、大孔减少,有大量的C-S-H凝胶生成,提高了混凝土结构的强度与耐久性. 相似文献
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研究了8种减水剂对拌和水表面张力和减水剂吸附特性对减水剂分散速率的影响.结果表明:除氨基磺酸盐系高效减水剂(ASF)会略微提高拌和水表面张力外,其余7种减水剂均能有效降低拌和水表面张力,聚羧酸系减水剂(PCE)侧链特性是影响拌和水表面张力的决定因素,而酸醚比的影响较小;萘系高效减水剂(NSF),ASF和脂肪族高效减水剂(SAF)的吸附量显著高于5种PCE,在较高掺量条件下,ASF和SAF会发生脱附,PCE中吸附基团(—COO~-)质量分数越高,吸附量越大;提高搅拌速率和延长搅拌时间可以提高PCE的分散效果,但对NSF、ASF和SAF的作用有限;拌和水表面张力降低并不能提高减水剂分散效果的发挥速率,而NSF、ASF、SAF和23PCE4因具有相对较高的吸附量,表现出较大的初始分散效果,但其余4种PCE并未表现出此对应关系. 相似文献
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Khalifa S. Al-Jabri Makoto Hisada Abdullah H. Al-Saidy S.K. Al-Oraimi 《Construction and Building Materials》2009,23(6):2132-2140
This research study was conducted to investigate the performance of high strength concrete (HSC) made with copper slag as a fine aggregate at constant workability and to study the effect of superplasticizer addition on the properties of HSC made with copper slag. Two series of concrete mixtures were prepared with different proportions of copper slag. The first series consisted of six concrete mixtures prepared with different proportions of copper slag at constant workability. The water content was adjusted in each mixture in order to achieve the same workability as that for the control mixture. Twelve concrete mixtures were prepared in the second series. Only the first mixture was prepared using superplasticizer whereas the other eleven mixtures were prepared without using superplasticizer and with different proportions of copper slag used as sand replacement. The results indicated that the water demand reduced by almost 22% at 100% copper slag replacement compared to the control mixture. The strength and durability of HSC were generally improved with the increase of copper slag content in the concrete mixture. However, the strength and durability characteristics of HSC were adversely affected by the absence of the superplasticizer from the concrete paste despite the improvement in the concrete strength with the increase of copper content. All concrete mixtures did not meet the strength and durability design requirements due to the segregation and dryness of the concrete paste. Therefore it can be concluded that the use of copper slag as sand substitution improves HSC strength and durability characteristics at same workability while superplasticizer is very important ingredient in HSC made with copper slag in order to provide good workability and better consistency for the concrete matrix. 相似文献
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エコセメントを用いたコンクリートは、一般のコンクリートより単位水量が増加し、スランプの経時変化も大きくなる傾向がある.本研究はエコセメントコンクリートにおよぼす流動化剤の流動化効果について、2種類の実験を行った.Phase.1では流動化剤添加量を変えた実験を行い、添加後のスランプ増大量、圧縮強度、耐久性について普通ポルトランドセメントと比較し、同等の流動化効果が得られることを明らかにした.Phase.2ではスランプロスしたコンクリートに流動化剤を後添加した場合のスランプ回復効果について実験を行い、Phase.1同様に普通ポルトランドセメントと同等の効果があることを明らかにした. 相似文献
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脂肪族羟基磺酸盐高效减水剂的合成及应用性能研究 总被引:5,自引:0,他引:5
以丙酮、甲醛和亚硫酸钠为主要原料合成了脂肪族羟基磺酸盐类高效减水剂,讨论了合成条件对产物分散 性能的影响并研究了这类高效减水剂的应用性能。丙酮、甲醛和亚硫酸钠的摩尔比为1:2.0:0.4、浓度为0.40g/ mL时反应3 h,所得的产物脂肪族羟基磺酸盐高效减水剂AHSS具有良好的分散性能。合成的高效减水剂AHSS 对水泥净浆有轻微缓凝作用;在混凝土中掺量为0.6%时,减水率达到19.5%,3 d、7 d、28 d抗压强度比分别为 185%、157%和144%,超过高效减水剂的国家标准要求。 相似文献