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Computer-aided Prediction of the ZrO_2 Nanoparticles' Effects on Tensile Strength and Percentage of Water Absorption of Concrete Specimens

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Journal of Materials Science & Technology 2012年第1期28卷 83-96页

作者： ali nazari shadi riahi Department of Materials Science and Engineering Saveh BranchIslamic Azad University

In the present paper, two models based on artificial neural networks and genetic programming for predicting split tensile strength and percentage of water absorption of concretes containing ZrO2 nanoparticles have been developed at different ages of curing. For building these models, training and testing using experimental results for 144 specimens produced with 16 different mixture proportions were conducted. The data used in the multilayer feed forward neural networks models and input variables of genetic programming models were arranged in a format of eight input parameters that cover the cement content, nanoparticle content, aggregate type, water content, the amount of superplasticizer, the type of curing medium, age of curing and number of testing try. According to these input parameters, in the neural networks and genetic programming models, the split tensile strength and percentage of water absorption values of concretes containing ZrO2 nanoparticles were predicted. The training and testing results in the neural network and genetic programming models have shown that two models have strong potential for predicting the split tensile strength and percentage of water absorption values of concretes containing ZrO2 nanoparticles. It has been found that neural network （NN） and gene expression programming （GEP） models will be valid within the ranges of variables. In neural networks model, as the training and testing ended when minimum error norm of network gained, the best results were obtained and in genetic programming model, when 4 genes were selected to construct the model, the best results were acquired. Although neural network have predicted better results, genetic programming is able to predict reasonable values with a simpler method rather than neural network.

关键词： Concrete Curing medium Zr02 nanoparticles Artificial neural network Geneticprogramming Split tensile strength Percentage of water absorption

Effects of CuO Nanoparticles on Microstructure,Physical,Mechanical and Thermal Properties of Self-Compacting Cementitious Composites

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Journal of Materials Science & Technology 2011年第1期27卷 81-92页

作者： ali nazari shadi riahi Department of Technical and Engineering Sciences Islamic Azad University(Saveh Branch)

In the present study,split tensile strength of self-compacting concrete with different amount of CuO nanoparticles has been *** nanoparticles with the average particle size of 15 nm were added partially to self compacting concrete and split tensile strength of the specimens has been *** results indicate that CuO nanoparticles are able to improve the split tensile strength of self compacting concrete and recover the negative effects of polycarboxylate superplasticizer on split tensile *** nanoparticle as a partial replacement of cement up to 4 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca（OH）2 amount at the early ages of *** increase of the CuO nanoparticles more than 4 wt% causes the decrease of the split tensile strength because of unsuitable dispersion of nanoparticles in the concrete *** peak appearance in conduction calorimetry tests,more weight loss in thermogravimetric analysis and more rapid appearance of related peaks to hydrated products in X-ray diffraction（XRD） results all also indicate that CuO nanoparticles up to4 wt% could improve the mechanical and physical properties of the ***,CuO nanoparticles could improve the pore structure of concrete and shift the distributed pores to harmless and few-harm pores.

关键词： Self-compacting concrete(SCC) CuO nanoparticles Split tensile strength Thermogravimetric analysis(TGA) X-ray diffraction(XRD) Pore structure

Computer-aided design of the effects of Cr_2O_3 nanoparticles on split tensile strength and water permeability of high strength concrete

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Science China(Technological Sciences) 2011年第3期54卷 663-675页

作者： ali nazari shadi riahi Department of Technical and Engineering Sciences Islamic Azad University Saveh Branch

In the present paper, two models based on artificial neural networks and genetic programming for predicting split tensile strength and percentage of water absorption of concretes containing Cr2O3 nanoparticles have been developed at different ages of curing. For purpose of building these models, training and testing using experimental results for 144 specimens produced with 16 different mixture proportions were conducted. The data used in the multilayer feed forward neural networks models and input variables of genetic programming models are arranged in a format of 8 input parameters that cover the cement content, nanoparticle content, aggregate type, water content, the amount of superplasticizer, the type of curing medium, age of curing and number of testing try. According to these input parameters, in the neural networks and genetic programming models the split tensile strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles were predicted. The training and testing results in the neural network and genetic programming models have shown that every two models have strong potential for predicting the split tensile strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles. It has been found that NN and GEP models will be valid within the ranges of variables. In neural networks model, as the training and testing ended when minimum error norm of network was gained, the best results were obtained and in genetic programming model, when 4 genes were selected to construct the model, the best results were acquired. Although neural network has predicted better results, genetic programming is able to predict reasonable values with a simpler method rather than neural network.

关键词： concrete curing medium Cr2O3 nanoparticles artificial neural network genetic programming split tensile strength percentage of water absorption

Compressive strength and abrasion resistance of concrete containing SiO_2 and CuO nanoparticles in different curing media

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Science China(Technological Sciences) 2011年第9期54卷 2349-2357页

作者： shadi riahi ali nazari Department of Materials Science and Engineering Saveh BranchIslamic Azad University

In the present study,abrasion resistance and compressive strength of concrete specimens containing SiO2 and CuO nanoparticles in different curing media have been *** cement was partially replaced by up to 2.0 wt%of SiO2 and CuO nanoparticles and the mechanical properties of the produced specimens were *** the nanoparticles content was found to increase the abrasion resistance of the specimens cured in water and saturated limewater,while this condition was not observed for compressive strength in the both curing *** enhancement of abrasion resistance was higher for the specimens containing SiO2 nanoparticles in both curing *** abrasion resistance and compressive strength of the specimens followed a similar regime as the nanoparticles increased for the specimens cured in saturated limewater,some experimental relationships has been presented to correlate these two properties of concrete for this curing *** the whole,it has been concluded that the abrasion resistance of concrete does not only depend on the corresponding compressive strength.

关键词： nanopartlcles abrasion resistance compressive strength curing medium thermogravimetric analysis XRD SEM

Effect of Layers Position on Fracture Toughness of Functionally Graded Steels in Crack Divider Configuration

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Journal of Materials Science & Technology 2011年第5期27卷 443-452页

作者： ali nazari Jamshid Aghazadeh Mohandesi shadi riahi Department of Technical and Engineering Sciences Islamic Azad University Department of Mining and Metallurgical Engineering Amirkabir University of Technology

In the present study, fracture toughness of functionally graded steels in crack divider configuration has been modeled. By utilizing plain carbon and austenitic stainless steels slices with various thicknesses and arrangements as electroslag remelting electrodes, functionally graded steels were produced. The fracture toughness of the functionally graded steels in crack divider configuration has been found to depend on the composites＇ type together with the volume fraction and the position of the containing phases. According to the area under stress-strain curve of each layer in the functionally graded steels, a mathematical model has been presented for predicting fracture toughness of composites by using the rule of mixtures. The fracture toughness of each layer has been modified according to the position of that layer where for the edge layers, net plane stress condition was supposed and for the central layers, net plane strain condition was presumed. There is a good agreement between experimental results and those acquired from the analytical model.

关键词： Fracture toughness Modeling Functionally graded steel Crack dividerconfiguration Position of the containing phases

Effects of Al_2O_3 nanoparticles on properties of self compacting concrete with ground granulated blast furnace slag (GGBFS) as binder

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Science China(Technological Sciences) 2011年第9期54卷 2327-2338页

作者： ali nazari shadi riahi Department of Materials Science and Engineering Saveh BranchIslamic Azad University

In this work, strength assessments and percentage of water absorption of self compacting concrete containing ground granulated blast furnace slag （GGBFS） and A1203 nanoparticles as binder have been investigated. Portland cement was replaced by different amounts of GGBFS and the properties of concrete specimens were investigated. Although it negatively impacts the physical and mechanical properties of concrete at early ages of curing, GGBFS was found to improve the physical and mechanical properties of concrete up to 45 wt% at later ages. A1203 nanoparticles with the average particle size of 15 nm were added partially to concrete with the optimum content of GGBFS and physical and mechanical properties of the specimens were measured. A1203 nanoparticle as a partial replacement of cement up to 3.0 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca（OH）2 amount at the early ages and hence increase strength and improve the resistance to water permeability of concrete specimens. The increase of the A1203 nanoparticles＇ content by more than 3.0 wt% would cause the reduction of the strength because of the decreased crystalline Ca（OH）2 content required for C-S-H gel formation. Several empirical relationships have been presented to predict flexural and split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing. Accelerated peak appearance in conduction calorimetry tests, more weight loss in thermogravimetric analysis and more rapid appearance of the peaks related to hydrated products in X-ray diffraction results, all indicate that A1203 nanoparticles could improve mechanical and physical properties of the concrete specimens.

关键词： concrete ground granulated blast furnace slag (GGBFS) Al203 nanoparticles compressive strength, flexural and splittensile strength pore structure thermogravimetric analysis conduction calorimetry

Retraction Note:Compressive strength and abrasion resistance of concrete containing SiO_(2) and CuO nanoparticles in different curing media

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Science China(Technological Sciences) 2022年第11期65卷 2790-2790页

作者： riahi shadi nazari ali Department of Materials Science and Engineering Saveh BranchIslamic Azad UniversitySavehIran

Retractionto:Science China Technological Sciences,2011,54:23492357https://doi.0rg/10.1007/s11431-011-4463-4The Journal Editorial Office has retracted this article because it shows significant overlap with a number of articles including those that were under consideration at the sametime[1-4].Additionally,the article shows evidence of peer review manipulation.

关键词： media strength resistance

Retraction Note: TiO_(2) nanoparticles' effects on properties of concrete using ground granulated blast furnace slag as binder

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Science China(Technological Sciences) 2021年第9期64卷 2066-2066页

作者： nazari ali riahi shadi Department of Materials Science and Engineering Saveh BranchIslamic Azad UniversitySavehIran

Retraction to:Science China Technological Sciences, 2011, 54:3109–3118https://***/10.1007/s11431-011-4421-1The Journal Editorial Office has retracted this article because it significantly overlaps with a number of ar... 详细信息

关键词： overlap ground furnace

Retraction Note: Effects of Al_(2)O_(3)nanoparticles on properties of self compacting concrete with ground granulated blast furnace slag(GGBFS) as binder

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Science China(Technological Sciences) 2021年第11期64卷 2566-2566页

作者： nazari ali riahi shadi Department of Materials Science and Engineering Saveh Branch.Islamic Azad UniversitySavehIran

Retraction to:Science China Technological Sciences, 2011, 54: 2327–2338 https://***/10.1007/s11431-011-4440-y The Journal Editorial Office has retracted this article because it significantly overlaps with a number of articles including those that were under consideration at the same time[1] and previously published [2–5].Additionally, there appears to be partial image overlap between panels within Figure 7 and with other publications by the same authors [1,5–7]. These SEM images are supposed to represent different materials and conditions.

关键词： overlap Figure Effects