Effect and mechanisms of nanomaterials on interface between aggregates and cement mortars
Effect and mechanisms of nanomaterials on interface between aggregates and cement mortars
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纳米材料对骨料与水泥砂浆界面的影响及机理
DOI：
10.1016/j.conbuildmat.2019.117942
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发表时间：
2020-04
影响因子：
7.4
通讯作者：
B.G. Han
中科院分区：
文献类型：
--
作者：
X.Y. Wang;S.F. Dong;A. Ashour;W. Zhang;B.G. Han
集料-水泥砂浆界面过渡区是混凝土中的最薄弱区域，对混凝土的性能有重要影响。研究了纳米填料对集料-水泥砂浆粘结强度和界面微观结构的影响及其作用机理。选取了8种具有代表性的纳米填料（即纳米SiO2、纳米TiO 2、纳米ZrO 2、未处理的多壁碳纳米管（MWCNTs）、羟基官能化的MWCNTs、镍包覆的MWCNTs、多层石墨烯（MLG）和纳米氮化硼（nano-BN））来制备具有放大骨料-水泥砂浆界面的试样，该试样可以通过三点弯曲试验来表征。试验结果表明，各种纳米填料均能提高集料与水泥砂浆之间的粘结强度。当纳米ZrO_2含量为2wt%、镍包覆MWCNTs含量为0.3wt%、BN含量为0.3wt%时，复合材料界面结合强度的相对/绝对值分别提高了2.1MPa/35.1%、2.32MPa/38.8%和2.56MPa/42.8%。扫描电子显微镜观察表明，纳米填料的存在下，可以改善水化产物和增加界面的致密性。能量色散谱仪结果表明，纳米填料在界面区的局部含量高于散装水泥砂浆。这些结果表明，纳米填料可以随着水的迁移向集料迁移，并在界面处富集，从而通过纳米核效应改善集料与水泥砂浆之间的粘结强度和界面微观结构。
As the weakest zone in concrete, the interfacial transition zone (ITZ) between aggregates and cement mortars has important effects on the properties of concrete. This paper aims to investigate the effects and mechanisms of nanofillers on the bond strength and interfacial microstructures between aggregates and cement mortars. A total of 8 representative types of nanofillers (namely nano-SiO2, nano-TiO2, nano-ZrO2, untreated multi-walled carbon nanotubes (MWCNTs), hydroxyl-functionalized MWCNTs, nickel-coated MWCNTs, multi-layer graphenes (MLGs), and nano boron nitride (nano-BN)) were selected to fabricate specimens with scale-up aggregate-cement mortar interface that can be characterized by the three-point bend test. The experimental results indicate that all types of nanofillers can enhance the bond strength between aggregates and cement mortars. The highest relative/absolute increases of 2.1 MPa/35.1%, 2.32 MPa/38.8% and 2.56 MPa/42.8% in interfacial bond strength are achieved by incorporating 2 wt% of nano-ZrO2, 0.3 wt% of nickel-coated MWCNTs, and 0.3 wt% of nano-BN, respectively. Scanning electron microscope observations show the presence of nanofillers can improve hydration products and increase interfacial compactness. Energy dispersive spectrometer results suggest that local content of nanofillers in the ITZ is higher than that in the bulk cement mortars. These findings indicate the nanofillers can transfer with water migration toward aggregates and enrich in ITZ, thus improving the bond strength and interfacial microstructures between aggregates and cement mortars through the nano-core effect.
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具有多功能/智能的多层石墨烯工程水泥基复合材料
影响因子：
13.1
作者：
Sun, Shengwei;Ding, Siqi;Ou, Jinping
通讯作者：
Ou, Jinping
DOI：
10.1201/9781482271522
发表时间：
1995-07
期刊：
--
影响因子：
--
作者：
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通讯作者：
J. Kropp;H. Hilsdorf
影响因子：
2.3
作者：
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Z. Li;B. Han;Xun Yu;Sufen Dong;Liqing Zhang;Xufeng Dong;J. Ou
影响因子：
3
作者：
Flores-Vivian, Ismael;Pradoto, Rani G. K.;Sobolev, Konstantin
通讯作者：
Sobolev, Konstantin
纳米二氧化硅对水泥基材料增强机理的理论计算和实验证据研究
影响因子：
2.9
作者：
L.Q. Zhang;N. Ma;Y.Y. Wang;B.G. Han;X. Cui;X. Yu;J.P. Ou
通讯作者：
J.P. Ou