Effect of silica fume and fly ash on hydration and microstructure evolution of cement based composites at low water–binder ratios

Rong, Zhidan; Sun, Wei; Xiao, H.J.; Wang, W.

doi:10.1016/j.conbuildmat.2013.11.023

Cited by 89 publications

(34 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The concrete obtained by using fly ash is relatively denser and more homogeneous than the concrete with no fly ash. Therefore, fly ash improves the mechanical properties of concrete due to decreasing the amount of CH and filling pores [20].…”

Section: Introductionmentioning

confidence: 99%

Analysis of Fly Ash Concrete with Scanning Electron Microscopy and X-Ray Diffraction

Uzbaş¹,

Aydın²

2019

Adv. Sci. Technol. Res. J.

View full text Add to dashboard Cite

In this study, the effects of using different ratios of fly ash on hydration products as well as the mechanical and microstructural properties of hardened concrete were investigated. Portland cement was replaced with 5%, 10%, 15% and 20% fly ash (FA) by weight. The microstructural properties of the obtained samples were investigated by means of X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Fly ash has negative effect on 7 days concrete strength; however, it was seen that fly ash increases the compressive strength of 28 and 90 days concrete. The XRD analysis showed that the ratio of calcium hydroxide (CH), which is produced by hydration, decreases depending on the concrete age and the amount of fly ash. The SEM analysis showed that the usage of fly ash decreases gaps and increases C-S-H which is also a hydration production. When Portland cement was replaced with 10% fly ash by weight, compressive strength has increased and microstructure of concrete has improved. The reason for this is filling of gaps by fly ash and the decrease in the amount of Ca(OH) 2 due to the reaction between fly ash and Ca(OH) 2 . Within this scope, the development in microstructure of fly ash concrete was evaluated in 90 days duration and a change of the development with compressive strength was investigated.

show abstract

Section: Introductionmentioning

confidence: 99%

Analysis of Fly Ash Concrete with Scanning Electron Microscopy and X-Ray Diffraction

Uzbaş¹,

Aydın²

2019

Adv. Sci. Technol. Res. J.

View full text Add to dashboard Cite

show abstract

“…A previous study [10] suggests that, the best mixing proportion of nano-SiO 2 in UHPCC was 3%. In this study, mixing proportion of nano-SiO 2 was fixed at 3% and mixing proportion of nano-CaCO 3…”

Section: Raw Materialsmentioning

confidence: 99%

“…Therefore, requirement on performance of concrete materials becomes higher and higher. Ultra-high performance concrete composite (UHPCC) featured by high strength, high toughness, high durability and strong deformation resistance is applied more extensively in harsh environment mentioned above and areas which have special requirements on structure; moreover it shows excellent performance in service process [3,4]. As to research on UHPC, three international conferences concerning UHPC have been held in Kassel University in German, in September 2005, March 2008, and March 2012 respectively.…”

Section: Introductionmentioning

confidence: 99%

Improvement of performance of ultra-high performance concrete based composite material added with nano materials

Pang¹,

Liu²

2016

Frattura Ed Integrità Strutturale

View full text Add to dashboard Cite

Ultra-high performance concrete (UHPC), a kind of composite material characterized by ultra high strength, high toughness and high durability. It has a wide application prospect in engineering practice. But there are some defects in concrete. How to improve strength and toughness of UHPC remains to be the target of researchers. To obtain UHPC with better performance, this study introduced nano-SiO2 and nano-CaCO3 into UHPC. Moreover, hydration heat analysis, X-Ray Diffraction (XRD), mercury intrusion porosimetry (MIP) and nanoindentation tests were used to explore hydration process and microstructure. Double-doped nanomaterials can further enhance various mechanical performances of materials. Nano-SiO 2 can promote early progress of cement hydration due to its high reaction activity and C-S-H gel generates when it reacts with cement hydration product Ca(OH)2. Nano-CaCO3 mainly plays the role of crystal nucleus effect and filling effect. Under the combined action of the two, the composite structure is denser, which provides a way to improve the performance of UHPC in practical engineering.

show abstract

“…Although the value of hybrid binders is greatly appreciated [11] and an extensive number of studies have been carried out in an effort to understand possible synergies between constituent materials such as fly ash and limestone in ternary blends [12] or to determine the reactivity of pozzolanic materials [13] in blended cements, there is still limited research on the synergies and material reactivities in very low PC content cementitious matrices. That is to say, research presented to date, investigates the synergistic effect of constituent materials for up to 20% PC replacement [14] or even higher PC replacement rates (55% PC and 35% fly ash and silica fume) but having a very low water to binder ratio (0.17) [15]. Qualitative characteristics of the hydration products resulting from the binary combinations of PC with either fly ash (FA) or silica fume (µS) or limestone (LS) have been studied in greater detail by Lothenbach et al [16].…”

Section: Introductionmentioning

confidence: 99%

A Step by Step Methodology for Building Sustainable Cementitious Matrices

Paine

2020

Applied Sciences

View full text Add to dashboard Cite

In an effort to produce cost-effective and environmentally friendly cementitious binders. mainly ternary (Portland cement + limestone + pozzolanas) formulations have been investigated so far. Various proportions of constituents have been suggested, all, however, employing typical Portland cement (PC) substitution rates, as prescribed by the current codes. With the current paper a step by step methodology on developing low carbon footprint binary, ternary and quaternary cementitious binders is presented (PC replacement up to 57%). Best performing binary (60% PC and 40% LS (limestone)) and ternary formulations (60% PC, 20% LS, 20% FA (fly ash) or 43% PC, 20% LS 37% FA) were selected on the grounds of sustainability and strength development and were further optimized with the addition of silica fume. For the first time a protocol for successfully selecting and testing binders was discussed and the combined effect of highly pozzolanic constituents in low PC content formulations was assessed and a number of successful matrices were recommended. The present paper enriched the current state of the art in composite low carbon footprint cementitious binders and can serve as a basis for further enhancements by other researchers in the field.

show abstract

Effect of silica fume and fly ash on hydration and microstructure evolution of cement based composites at low water–binder ratios

Cited by 89 publications

References 16 publications

Analysis of Fly Ash Concrete with Scanning Electron Microscopy and X-Ray Diffraction

Analysis of Fly Ash Concrete with Scanning Electron Microscopy and X-Ray Diffraction

Improvement of performance of ultra-high performance concrete based composite material added with nano materials

A Step by Step Methodology for Building Sustainable Cementitious Matrices

Contact Info

Product

Resources

About