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Thermal Conductivity And Microstructure Of Concrete Using

Thermal Conductivity and Microstructure of Concrete Using ...

Thermal Conductivity and Microstructure of Concrete Using Recycle Glass as a Fine Aggregate Replacement Renga Rao 1Krishnamoorthy , Juvinia Augustine Zujip 2

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Thermal Conductivity and Microstructure of Concrete Using ...

Influencing factors on thermal conductivity of concrete are investigated using The Unitherm TM Model 6000 Guarded Hot Plate Thermal Conductivity Instrument. A total of 36 concrete mixes were produced with different water cement ratios (0.4 and 0.5). Recycled glass was used to replace fine aggregate in proportions of 0%, 10%, 20%, 30%, 40%, and 50%.

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Analysis of thermal conductivity of porous concrete using ...

Sep 10, 2019  The thermal conductivity of porous concrete was studied with the microstructure-based numerical model. The following conclusions were concluded from this study: (1) The predicted effective thermal conductivity of porous concrete ranges from 0.43 to 0.72 Wm −1 K −1, while the measured values range from 0.47 to 0.82 Wm −1 K −1. There is ...

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Analysis of thermal conductivity of porous concrete using ...

The effects of microstructure feature on thermal conductivity of porous concrete were studied. Although the thermal conductivity of porous concrete decreases as the porosity increases in general, the variation of thermal conductivity is affected by the tortuosity and orientation of air void and aggregate contacts.

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Microstructure and Thermal Conductivity of Hydrated ...

The thermal conductivity of a porous material is controlled by the thermal conductivities of its components and their spatial arrangement within the composite structure, e.g., the material’s microstructure.

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(PDF) Properties and Microstructure Distribution of High ...

The proposed concrete mixture, which has 100% of expanded perlite aggregate achieved reduction percentage of thermal conductivity around 62% (0.69 W/mK) relative to normal weight concrete the ...

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Evaluation of thermal conductivity of asphalt concrete ...

Jun 05, 2015  The thermal conductivity of asphalt concrete is affected by its volumetric parameters and thermal properties of each component. If an analytical model is available to predict the effective thermal conductivity of asphalt concrete based on its microstructure, experiment costs can be significantly saved.

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(PDF) Thermal conductivity of the curing concrete

Thermal conductivity theory Fourier's law [167] k eff = heat flux in watt, and k = thermal conductivity (W/m K) d T = temperature gradient in Kelvin d t = thickness of the material in m k eff = 0 ...

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Experimental Study on Thermal Conductivity of Concrete ...

Dec 02, 2019  Insulation performance of concrete must be secured in order to minimize the energy loss of buildings. For enhancing the insulation performance of concrete, this study conducts research on thermal conductivity of concrete using the Eco-friendly material called ferronickel slag (FNS) binder, and compares the mechanical properties and insulation properties to the concrete using ordinary

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Characterization and simulation of microstructure and ...

Oct 01, 2013  Then the thermal conductivity was calculated using the Fourier heat flow equation: (4) k exp = Q D A Δ T where k exp is thermal conductivity of the tested sample. Q is the time rate of heat flow. D is the thickness of the tested sample. A and ΔT are cross-sectional area and temperature difference across the sample, respectively. 2.5.

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Thermal Conductivity and Microstructure of Concrete Using ...

Influencing factors on thermal conductivity of concrete are investigated using The Unitherm TM Model 6000 Guarded Hot Plate Thermal Conductivity Instrument. A total of 36 concrete mixes were produced with different water cement ratios (0.4 and 0.5). Recycled glass was used to replace fine aggregate in proportions of 0%, 10%, 20%, 30%, 40%, and 50%.

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(PDF) Determination of Effective Thermal Conductivity of ...

effective thermal conductivity of asphalt concrete using a FE mod- eling approach with randomly generated aggregate microstructures. The following conclusions were derived from the analysis:

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Strength, Microstructure, and Thermal Conductivity of the ...

Strength, Microstructure, and Thermal Conductivity of the Insulation Wallboards Prepared With Rice Husk Fiber and Recycled Concrete Aggregates PLoS One. 2018 Sep 19;13(9):e0203527. doi: 10.1371/journal.pone.0203527. eCollection 2018. Authors Xiaoniu Yu 1 ...

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Microstructure and Thermal Conductivity of Hydrated ...

The thermal conductivity of a porous material is controlled by the thermal conductivities of its components and their spatial arrangement within the composite structure, e.g., the material’s microstructure.

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Thermal conductivity of concrete – A review - ScienceDirect

Nov 01, 2018  The thermal conductivity of concrete in saturated condition is greater than in dry state due to the thermal conductivity of water, which is 25 times higher than air , . Moreover, the thermal conductivity of water used in mixtures is reliant on the temperature. ... Thermal conductivity and microstructure of concrete using recycle glass as a fine ...

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Effective thermal conductivity of clayey aerated concrete ...

The thermal conductivity is computed from the following equation by applying a least-squares approach to the data acquired between 220 and 400 s. TD Q 4ˇ [Ln t+ Cte]: (1) According to Laurent [11] the thermal conductivity obtained using a ‘line source’ method is usually accurate to within 5%. 2.3.2. Measurement of the thermal conductivity ...

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Experimental Study on Thermal Conductivity of Concrete ...

Insulation performance of concrete must be secured in order to minimize the energy loss of buildings. For enhancing the insulation performance of concrete, this study conducts research on thermal conductivity of concrete using the Eco-friendly material called ferronickel slag (FNS) binder, and compares the mechanical properties and insulation properties to the concrete using ordinary Portland ...

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Characterization and simulation of microstructure and ...

Oct 01, 2013  Then the thermal conductivity was calculated using the Fourier heat flow equation: (4) k exp = Q D A Δ T where k exp is thermal conductivity of the tested sample. Q is the time rate of heat flow. D is the thickness of the tested sample. A and ΔT are cross-sectional area and temperature difference across the sample, respectively. 2.5.

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Strength, microstructure, and thermal conductivity of the ...

Sep 19, 2018  This paper intends to evaluate the influence of content of rice husk fiber and cementitious materials on mechanical properties and thermal conductivity of thermal insulation wallboards. Thermal insulation wallboard contained different mass of rice husk fiber was prepared when the weight of cement, fly ash, cellulose ether, naphthalene superplasticizer, and recycled concrete aggregates was equal.

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Pore Structure and Thermal Conductivity of Cryogenic

D. Thermal Conductivity Determination . The thermal conductivity of the concrete mixtures at ambient temperature was determined using a KD2 thermal properties analyzer (Decagon Devices, Inc., Washington, USA) with 60 mm probe length. The device provides direct readings of the thermal conductivity

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Microstructure of Concrete IntechOpen

Oct 27, 2015  Figure 1. Left: polished section of concrete specimen. Right: microstructure of a hydrated cement paste [1].Concrete with superior properties such as high compressive strength and excellent durability can be produced by taking into account the following: (i) optimizing particle size distribution to obtain high density; (ii) using water reducer agents to reduce water/cement (w/c) ratio;

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Air-entrained Concrete: Relationship between Thermal ...

Air-entrained Concrete: Relationship between Thermal Conductivity and Pore Distribution Analyzed by X-Ray Tomography 508 concretes [5]. Thus, the density of concrete can be decreased by using light aggregates or air-entrained concrete (as in this work) in which air-bubbles are entrapped in the mortar matrix by means of a suitable aerating agent.

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Determination of Effective Thermal Conductivity of Asphalt ...

Dec 12, 2015  Three-phase microstructure models (asphalt binder, aggregate, and air void) of asphalt concrete were randomly generated based on aggregate sizes and gradations. A finite-element (FE) model was developed to calculate the effective thermal conductivity of asphalt concrete by applying a steady heat transfer process.

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(PDF) Determination of Effective Thermal Conductivity of ...

The aspect ratios of aggregates ranged from 1 to 3. The variation of the effective thermal conductivity of asphalt concrete with aspect ratio is shown in Fig. 10. It shows that as the aspect ratio of aggregate increases, the effective thermal conductivity of asphalt concrete in which aggregates were horizontally oriented decreased.

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Experimental Study on Thermal Conductivity of Concrete ...

Insulation performance of concrete must be secured in order to minimize the energy loss of buildings. For enhancing the insulation performance of concrete, this study conducts research on thermal conductivity of concrete using the Eco-friendly material called ferronickel slag (FNS) binder, and compares the mechanical properties and insulation properties to the concrete using ordinary Portland ...

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MICROSTRUCTURE, MECHANICAL AND THERMAL

2.3.3.3 Thermal behaviour 16 2.3.4 Microstructure behaviours of foamed concrete 17 2.4 Geopolymer concrete 18 2.4.1 Background 18 2.4.2 Use of fly ash in geopolymer concrete 20 2.4.3 Factors affecting the geopolymer concrete properties 22 2.4.3.1 Alkaline solution 22

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Strength, microstructure, and thermal conductivity of the ...

Sep 19, 2018  This paper intends to evaluate the influence of content of rice husk fiber and cementitious materials on mechanical properties and thermal conductivity of thermal insulation wallboards. Thermal insulation wallboard contained different mass of rice husk fiber was prepared when the weight of cement, fly ash, cellulose ether, naphthalene superplasticizer, and recycled concrete aggregates was equal.

More

Effective thermal conductivity of clayey aerated concrete ...

The thermal conductivity is computed from the following equation by applying a least-squares approach to the data acquired between 220 and 400 s. TD Q 4ˇ [Ln t+ Cte]: (1) According to Laurent [11] the thermal conductivity obtained using a ‘line source’ method is usually accurate to within 5%. 2.3.2. Measurement of the thermal conductivity ...

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Thermal and physical properties of concrete containing ...

Thermal shock causes a denser microstructure than thermal aging due to the rehydration of the components. The color change, mass loss, thermal conductivity, wave velocity, and compressive strength of the concrete are related to the rehydration of components in concrete and the relationships between these parameters show good linear relationships.

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Pore Structure and Thermal Conductivity of Cryogenic

D. Thermal Conductivity Determination . The thermal conductivity of the concrete mixtures at ambient temperature was determined using a KD2 thermal properties analyzer (Decagon Devices, Inc., Washington, USA) with 60 mm probe length. The device provides direct readings of the thermal conductivity

More

Air-entrained Concrete: Relationship between Thermal ...

Air-entrained Concrete: Relationship between Thermal Conductivity and Pore Distribution Analyzed by X-Ray Tomography 508 concretes [5]. Thus, the density of concrete can be decreased by using light aggregates or air-entrained concrete (as in this work) in which air-bubbles are entrapped in the mortar matrix by means of a suitable aerating agent.

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Effect of Elevated Temperature on Mechanical Properties ...

B. Microstructure Concrete Preparation The blended concrete mix was prepared using ordinary Portland cement that was partially substituted by 0, 5, 10, 15 and 20% silica flour as illustrated in Table II. The concrete was prepared using water/binder ratio of 0.5 wt% of binder. The concrete was molded into 100 mm cubes for

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Microstructure of Concrete IntechOpen

Oct 27, 2015  Figure 1. Left: polished section of concrete specimen. Right: microstructure of a hydrated cement paste [1].Concrete with superior properties such as high compressive strength and excellent durability can be produced by taking into account the following: (i) optimizing particle size distribution to obtain high density; (ii) using water reducer agents to reduce water/cement (w/c) ratio;

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(PDF) Guide to Thermal Properties of Concrete and Masonry ...

Guide to Thermal Properties of Concrete and Masonry Systems. Noor alhuda. Related Papers. ACI 122R-02 Guide to Thermal Properties of Concrete and Masonry Systems.

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ELECTRICAL CONDUCTIVITY OF CONCRETE

concrete has resistivity in the range of 1012 ohm-mm. Hence oven dry concrete acts as an insulator. The variation in the measured electrical resistivity in wet and dry concrete can be interpreted to find that the electrical conductivity of concrete is a significant effect of the evaporable water present in it. Therefore it can be

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Factors Effecting the Thermal and Microstructures of ...

May 12, 2015  Abstract. This paper researches a measurement of thermal conductivity of crushed recycled glass concrete using Unitherm TM Model 6000 Guarded Hot Plate Thermal Conductivity Instrument. Thirty six (36) samples of recycled glass concrete was produced with two types of water to cement ratio (0.4 and 0.5).

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MICROSTRUCTURE-BASED PREDICTION OF THERMAL

knowledge of its thermal properties. Heat capacity, thermal conductivity and coefficient of thermal expansion are the properties that play important roles in the structural behaviour of concrete structures (RC) at early ages, especially the massive ones [1], which are particularly prone to significant thermal stress development.

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Case studies on the influence of microstructure voids on ...

The determination of the thermal conductivity can be carried out using the electrical analogy. So, microstructure models have been converted in electrical fractal patterns. This fractal procedure is characterized by a close relationship with the actual microstructure and prevent papers has been validate it with experimental data in a series of ...

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