Enhancement of nano-alumina on long-term strength of Portland cement and the relation to its influences on compositional and microstructural aspects

Shao, Qi-Yu; Zheng, Keren; Zhou, Xueguang; Zhou, Jin; Zeng, Xiaohui

doi:10.1016/j.cemconcomp.2019.01.016

Cited by 54 publications

(10 citation statements)

References 30 publications

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“…Nanomaterials possess small volume and adding nanomaterials such as nano-silica (NS), Sardon et al used (3-aminopropyl) triethoxysilane (APTES)-modified SiO 2 to reduce the agglomeration of NS significantly [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ]. The addition of nano-titanium dioxide (nano-TiO 2 ) [ 14 ], nano-iron (nano-Fe 2 O 3 ) [ 15 ], nano-alumina (nano-Al 2 O 3 ) [ 16 ], carbon nanotube (CNTs) [ 17 , 18 , 19 ], and nano-clay particles [ 20 ] into cementitious composite can improve its overall properties.…”

Section: Introductionmentioning

confidence: 99%

High-Strength, Waterproof, Corrosion-Resistant Nano-Silica Carbon Nanotube Cementitious Composites

Shi

2020

Materials

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This study aims to prepare a nano-silica-carbon nanotube (NS-CNT) elastic composite using NS (nano-silica), CNTs (carbon nanotube), and (D3F) trifluoropropyltrimethoxysilane. The results show that the activated NS could promote the hydrolysis of D3F. Polymerization products of nano-silica and D3F are uniformly adhered onto the surfaces of CNTs, thereby forming a NS-CNT composite. The composite is composed of irregular ellipsoids of 3–12 μm in length and 2–10 μm in diameter. The activated NS-CNT composite material effectively promotes the further hydration of (CaOH)2 in the cement to form hydrated calcium silicate, and further dehydration–condensation between the surface hydroxyl group of the composite material and the inherent hydroxyl group of (CaOH)2. The cementitious composite-based composites containing the activated NS-CNT exhibit high mechanical strengths, high water resistances, and good durability and corrosion resistance. The chemical characterizations reveal the morphology, nucleation mode of the composite, and its influence on the hydration structure and products of cementitious composite.

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Section: Introductionmentioning

confidence: 99%

High-Strength, Waterproof, Corrosion-Resistant Nano-Silica Carbon Nanotube Cementitious Composites

Shi

2020

Materials

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“…Dissolved nano-alumina precipitates as monosulfate. The formation of monosulfate and monocarbonate related to the presence of nano-alumina is demonstrated in Equations (3) and (4), respectively, which leads to a decrease in porosity, and therefore leads to an improvement in strength by increasing the formation of solids [ 45 ]. Al 2 O 3 ·xH 2 O + 2OH − → 2Al(OH) 4 − + (x − 3)H 2 O 2Al(OH) 4 − + 3Ca(OH) 2 + Ca 2+ + SO 4 2− + 6H 2 O → 3CaO·Al 2 O 3 ·CaSO 4 ·12H 2 O + 2OH − 2Al(OH) 4 − + 3Ca(OH) 2 + Ca 2+ + CO 3 2− + 5H 2 O → 3CaO·Al 2 O 3 ·CaCO 3 ·11H 2 O + 2OH − …”

Section: Methodsmentioning

confidence: 99%

“…Similarly, as demonstrated in Figure 5 and the key observations compiled in Table 2 , the addition of other nanomaterials such as nano-alumina, nano-MgO, nano-ZnO, nano-TiO 2 , nano-clay, and carbon nanotubes (CNT) up to the optimum dosage improves the compressive strength [ 52 , 54 , 56 , 61 , 91 , 99 , 129 , 130 , 131 ]. Clearly from the XRD images ( Figure 6 ), the compressive strength increase is due to the flaw-bridging effect and filler effect at the nano level [ 45 , 132 , 133 , 134 , 135 , 136 ], while agglomeration prevents the hydration process due to the formation of weak bonds within the mortar matrix [ 44 , 137 , 138 , 139 , 140 , 141 ]. From the XRD images ( Figure 6 ), it is quite clear that the formation of CSH compounds occurs from the start of mixing in the case of nano-silica, while it is neutral in the case of nano–titanium oxide.…”

Section: Properties and Methodsmentioning

confidence: 99%

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Comparative Overview of the Performance of Cementitious and Non-Cementitious Nanomaterials in Mortar at Normal and Elevated Temperatures

et al. 2021

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Nanotechnology has emerged as a field with promising applications in building materials. Nanotechnology-based mortars are examples of such building materials that have widespread applications in the construction industry. The main nanomaterials used in mortars include nano-silica, nano-magnesium oxide, nano-alumina, nano-titanium oxide, nano-zinc oxide, nano-clay, and nano-carbon. This review paper presents a summary of the properties and effects of these nanomaterials on cement mortar in terms of its fresh-state and hard-state properties. The fresh-state properties include the setting time, consistency, and workability, while the hard-state properties include mechanical properties such as compressive, flexural, tensile strengths, as well as the elasticity modulus, in addition to durability properties such as water absorption, shrinkage strain, strength loss due to freeze–thaw cycles, and chloride penetration, among others. Different nanomaterials cause different physical and chemical alterations within the microstructures of cement mortar. Therefore, the microstructural characterization and densification of mortar are discussed in detail at varying temperatures. In general, the involvement of nanomaterials in cement mortar influences the fresh-state properties, enhances the mechanical properties, and impacts the durability properties, while reducing the porosity present in the mortar matrix. Cementitious nanomaterials can create a pathway for the easy injection of binding materials into the internal microstructures of a hydration gel to impact the hydration process at different rates, whereas their non-cementitious counterparts can act as fillers. Furthermore, the research gaps and future outlook regarding the application of nanomaterials in mortar are discussed.

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“…The effect of nanoparticles as partial cement replacement in the concrete mix has been studied by many researchers in recent years. Nano-SiO 2 is the most widely investigated nanoparticle [19,[51][52][53] while the effect of adding other partials such as nano-TiO 2 [22,54,55], nano-Al 2 O 3 [9,56,57], nano-ZnO 2 [58,59], nano-Fe 2 O 3 [10,60], nano-CuO [61], nano-SnO 2 , nano-ZrO 2 [62], nano-TiO 2 [63], carbon nanotubes [64], carbon nano-fibers [45], polycarboxylates [65], nano-Cr 2 O 3 [48,66], nano-clay [45] and nano-CaCO 3 [62,67] in properties of fresh and hardened concrete has been investigated so far. For example, Tawfik et al [68] evaluated the effect of nano-waste ceramic and nano-silica on the mechanical properties of hardened concrete.…”

Section: Nanoparticlesmentioning

confidence: 99%

Effect of Alumina Additives on Mechanical and Fresh Properties of Self-Compacting Concrete: A Review

et al. 2021

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Self-compacting concrete (SCC) has been increasingly used in the construction sector due to its favorable characteristics in improving various durability and rheology aspects of concrete such as deformability and segregation resistance. Recently, the studies on the application of nano-alumina (NA) produced from factory wastes have been significantly considered to enhancing the performance, and mechanical strength, of SCC. Many experimental works show that NA can be used in SCC with appropriate proportion to enjoy the benefits of improved microstructure, fresh and hardened properties, durability, and resistance to elevated temperature. However, a limited detailed review is available to particularly study using NA to improve the performance of SCC, so far. Hence, the present study is conducted to fill the existing gap of knowledge. In this study, the effect of using NA in improving rheological, mechanical parameters, and elevated temperature resistance of SCC is reviewed. This research summarized the studies in this area, which have been different from the previous researches, and provided a discussion on limitations, practical implications, and suggestions for future studies.

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Enhancement of nano-alumina on long-term strength of Portland cement and the relation to its influences on compositional and microstructural aspects

Cited by 54 publications

References 30 publications

High-Strength, Waterproof, Corrosion-Resistant Nano-Silica Carbon Nanotube Cementitious Composites

High-Strength, Waterproof, Corrosion-Resistant Nano-Silica Carbon Nanotube Cementitious Composites

Comparative Overview of the Performance of Cementitious and Non-Cementitious Nanomaterials in Mortar at Normal and Elevated Temperatures

Effect of Alumina Additives on Mechanical and Fresh Properties of Self-Compacting Concrete: A Review

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