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Combined Effect of Silicon Dioxide and Titanium Dioxide Nanoparticles on Concrete Properties

Al-Rbaihat Raed, Al-Marafi Mohammad Nour

Journal of Ecological Engineering

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2023

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Vol. 24, nr 12

319--335

EN

Nanoconcrete is an attractive research area because of its recent practical applications in building materials technologies. This study investigates the individual and combined effects of using nanoparticles in concrete mixtures as a cement substitute. Microscopic images are also used to determine changes in the microstructure of modified concrete in the present study. Concrete’s thermal and mechanical properties, including thermal conductivity (k), specific heat capacity (C), thermal diffusivity (α), and compressive strength (σ), are the leading concrete characteristics examined. The current study used different percentages (0%, 1%, 3%, and 5%) of nano-SiO2, nano-TiO2, and combined nano-SiO2/TiO2 particles as cement substitutes for 7 and 28 days of curing to examine the characteristics of nanoconcrete compared to conventional concrete (CC). The results indicated that adding individual nanoparticles to CC could improve concrete’s thermal and mechanical properties. Among the investigated nanomaterials (nano-SiO2, nano-TiO2, and combined nano-SiO2/TiO2 particles), nano-SiO2 was superior in that context. The optimal thermal properties of nanoconcrete were achieved when 5% nano-SiO2 (C-S5 specimen) was added. The k and α coefficients of sample C-S5 compared to the CC specimen were reduced by 65.6% and 80.3%, respectively, while the C coefficient was increased by 12.8%. Meanwhile, the optimal compressive strength coefficient of nanoconcrete was achieved when 3% nano-SiO2 (C-S3 specimen) was added, where the compressive strength coefficient of sample C-S3 compared to sample CC was increased by 19.6%. In contrast, for the combined effect, the thermal properties of concrete were improved, but the compressive strength coefficient of concrete was reduced. Overall, the present experimental findings offer valuable information about the impact of nanotechnology on high-performance concrete to save energy in buildings.

2

Concrete nanomodification with selected nanoparticles

Iskra-Kozak W., Konkol J.

Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture

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2018

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z. 65, nr 4

113--120

EN

The aim of the paper is to present the state of the art and technology in the field of concrete nanomodification. This new approach to the design and manufacture of materials by modifying their microstructure at the nanometric level is increasingly used also in the case of concrete. Owing to C-S-H phase changes concrete porosity and permeability can be reduced, which increases concrete durability. The improvement of concrete properties and the possibility of the manufacture of new building materials are the most important benefits of the impact of nanotechnology on construction. The paper describes the most commonly used nanoparticles in concrete technology, including nano-SiO2 , nano-TiO2 , nano-Fe2O3 , Fe3O4.

3

Właściwości nanokompozytów cementowych

Kostrzanowska-Siedlarz A.

Magazyn Autostrady

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2017

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Nr 5

91--95

PL

W artykule przedstawiono podział nanokompozytów cementowych ze względu na ich właściwości i wprowadzony nanomateriał. Na podstawie dokonanego podziału przedstawiono właściwości nanobetonów z wyszczególnieniem grupy betonów inteligentnych, głównie nanoczujników i sensorów. Artykuł wskazuje cele wprowadzania nanomateriałów do matrycy cementowej oraz problemy w składzie betonów wynikające z natury tych materiałów.

EN

The distribution of cement nanocomposites by their properties and the introduction of nanomaterials is presented in the paper. Based on the division, the properties of nanoconcrete detailing the group of intelligent concretes, mainly nanosensors, are presented. The goals of introducing nanomaterials into the cement matrix and the problems in the composition of concrete inherent in the nature of these materials are indicated in the paper.

4

Effect of nano silica on mechanical properties and durability of normal strength concrete

Gopinath S., Mouli P.C., Murthy A.R., Iyer N.R., Maheswaran S.

Archives of Civil Engineering

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2012

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Vol. 58, nr 4

433-444

EN

Nano technology is an emerging field of interest for civil engineering application. Among the nano materials presently used in concrete, nano-silica possess more pozzolanic nature. It has the capability to react with the free lime during the cement hydration and forms additional C-S-H gel giving strength, impermeability and durability to concrete. Present paper investigates the effects of addition of nano silica in normal strength concrete. Three types of nano-silica in the form of nano suspension having different amount of silica content have been investigated. Mix design has been carried out by using particle packing method. X-Ray diffraction (XRD) analysis has been carried out to find the chemical composition of control concrete and nano modified concrete. Further, experimental investigations have been carried out to characterize the mechanical behaviour in compression, tension and flexure. It has been observed that the addition of nano-silica in normal strength concrete increased the compressive strength and decreased the spilt tensile strength and flexural strength. Also, Rapid chloride permeability test (RCPT) has been conducted to know the chloride permeability of control concrete, nano modified concrete, and nano coated concrete. It has been observed that the chloride permeability is less for nano coated concrete.

5

Nanotechnologia w budownictwie

Czarnecki L.

Przegląd Budowlany

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2011

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R. 82, nr 1

40-53

PL

Zaproszenie do przygotowania referatu generalnego pod powyższym tytułem na 56 Konferencję KILiW PAN i KN PZITB przyjąłem jako zaszczytne wyróżnienie, ale równocześnie jako trudne zadanie. W 2006 roku opublikowałem w "Inżynierii i Budownictwie" artykuł pt "Nanotechnologia - wyzwaniem inżynierii materiałów budowlanych" ; publikacja ta została rozpowszechniona wśród uczestników Konferencji Krynica 2006. Uważałem wówczas, że w 10 lat po przyznaniu Nagrody Nobla za sztandarowe osiągnięcie nanotechnologii - fulereny, właściwe jest sformułowanie pytania: czy nanotechnologia w odniesieniu do budownictwa może stać się szansą rozwoju dziedziny? Obecnie po upływie kolejnych pięciu lat uważam to pytanie nadal za otwarte. Dzieje się tak mimo, że w 2005 roku międzynarodowe grono 63 ekspertów sklasyfikowało "budownictwo" na 8 pozycji beneficjentów rozwoju nanotechnologii do 2015 roku.

EN

The basic definitions are given in the paper. The development of nanotechnology and its principle areas of research are discussed. The considerations are oriented on engineering building materials, including concrete technology. The fundamental question is formulated: will nanotechnology change our vision, expectations and abilities to develop construction? The paper presents an attempt to answer to this question. Exploitation of nanosize effects is an important challenge in the modern time. There is still much to be said for it.