Transient Pulse Method for Measuring of Heat Conductivity of Autoclaved Aerated Concrete

2014 ◽  
Vol 899 ◽  
pp. 466-469
Author(s):  
Marián Vertaľ ◽  
Dušan Katunský ◽  
Jozef Šimiček
Keyword(s):  
Water Content ◽  
Heat Conductivity ◽  
Building Materials ◽  
Pulse Method ◽  
Building Construction ◽  
Basic Material ◽  
Material Parameters ◽  
Aerated Concrete ◽  
Moisture Dependence ◽  
Stationary Measurement

The heat conductivity, specific heat and bulk density are the basic material parameters and thus indispensable. There are numbers of methods used for measurement of heat conductivity. However, the non-stationary (transient pulse method) measurements methods are preferred for description of heat conductivity moisture dependence. This article discusses on the establishment dependence of heat conductivity on water content for selected porous building materials by using non stationary measurement methods. Dependence of the thermal conductivity on the water content is necessary for coupled heat, air and moisture (HAM) simulation in building construction.

scholarly journals The analysis of heat conductivity coefficient of the aerated concrete building barriers depending on moisture changes

2011 ◽  
Vol 8 (1) ◽  
pp. 107-116
Author(s):  
Zbigniew Suchorab ◽  
Danuta Barnat-Hunek
Keyword(s):  
Heat Conductivity ◽  
Building Materials ◽  
Winter Season ◽  
Time Domain Reflectometry ◽  
Heat Conductivity Coefficient ◽  
Water Desorption ◽  
Concrete Building ◽  
Absorbing Material ◽  
Aerated Concrete ◽  
Comfort Parameters

The article is sacrificed to the aerated concrete building barriers moisture phenomenon. Water, which increases heat conductivity of building materials is the reason of the increased heat loses during the winter season. The result of this phenomenon is the decrease of indoor heat comfort parameters. Aerated concrete is a strongly water absorbing material with elongated time of water desorption. Capillary-porous structure of the described medium makes is highly prone to water influence what is the reason of the detailed analysis of heat conductivity coefficient in relation to moisture. In this article it is analyzed and compared the influence of moisture changes on heat parameters of the aerated concrete with the bulk densities of 400 and 600 kg/m3 using the reflectometric techniques TDR (Time Domain Reflectometry).

Laboratory Evaluation of the Dual-Probe Heat-Pulse Method for Measuring Soil Water Content

2003 ◽  
Vol 2 (3) ◽  
pp. 389
Author(s):  
J. M. Basinger ◽  
G. J. Kluitenberg ◽  
J. M. Ham ◽  
J. M. Frank ◽  
P. L. Barnes ◽  
...  
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Pulse Method ◽  
Heat Pulse ◽  
Laboratory Evaluation ◽  
Dual Probe

Effect of water content on microwave dielectric properties of building materials

2020 ◽  
Vol 263 ◽  
pp. 120107
Author(s):  
Romain Damez ◽  
Philippe Artillan ◽  
Arthur Hellouin de Menibus ◽  
Cédric Bermond ◽  
Pascal Xavier
Keyword(s):  
Dielectric Properties ◽  
Water Content ◽  
Building Materials ◽  
Microwave Dielectric Properties ◽  
Effect Of Water ◽  
Microwave Dielectric

scholarly journals Cure Kinetics and Inverse Analysis of Epoxy-Amine Based Adhesive Used for Fastening Systems

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3853
Author(s):  
Bilen Emek Abali ◽  
Michele Zecchini ◽  
Gilda Daissè ◽  
Ivana Czabany ◽  
Wolfgang Gindl-Altmutter ◽  
...  
Keyword(s):  
Inverse Analysis ◽  
Building Materials ◽  
Cure Kinetics ◽  
Accurate Estimation ◽  
Curing Process ◽  
Degree Of Cure ◽  
Material Parameters ◽  
Epoxy Amine ◽  
Thermosetting Polymers ◽  
Material Equation

Thermosetting polymers are used in building materials, for example adhesives in fastening systems. They harden in environmental conditions with a daily temperature depending on the season and location. This curing process takes hours or even days effected by the relatively low ambient temperature necessary for a fast and complete curing. As material properties depend on the degree of cure, its accurate estimation is of paramount interest and the main objective in this work. Thus, we develop an approach for modeling the curing process for epoxy based thermosetting polymers. Specifically, we perform experiments and demonstrate an inverse analysis for determining parameters in the curing model. By using calorimetry measurements and implementing an inverse analysis algorithm by using open-source packages, we obtain 10 material parameters describing the curing process. We present the methodology for two commercial, epoxy based products, where a statistical analysis provides independence of material parameters leading to the conclusion that the material equation is adequately describing the material response.

scholarly journals Analysis of Porous Structure in Autoclaved Materials Modified by Glass Sand

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 408
Author(s):  
Anna Stepien
Keyword(s):  
Computed Tomography ◽  
Building Materials ◽  
Micro Ct ◽  
Structure Building ◽  
Acoustic Insulation ◽  
Ct Analysis ◽  
Glass Sand ◽  
Aerated Concrete ◽  
Wall Construction ◽  
Dominant Phase

This paper describes the use of glass sand in the production of autoclaved bricks. Traditional autoclaved materials consist of SiO2, CaO, and H2O. The purpose of the tests is to analyze the possibility of using glass sand in autoclaved materials and to determine their properties and durability. Depending on the structure, building materials can have porosities ranging from 0% (glass, metals) to over 90% (thermal insulation materials such as aerated concrete). Porosity of materials is directly related to the strength of materials and their density, and further to the thermal and acoustic insulation properties of products used especially for external wall construction, i.e., bricks, concrete, and aerated concrete. This type of silicate brick is formed at a temperature of 203 °C, therefore the dominant phase forming the microstructure is tobermorite, in contrast to the C-S-H phase, which dominates in concretes and which is characterized by a larger specific surface. The nature of pores, their number, appearance and arrangement in the material can be studied using computer techniques (SEM, XRD, computed tomography, porosimetry). Computed tomography (micro-CT analysis) showed that the number of voids in the material modified by glass sand is about 20% in relation to the weight of the product. The density of the product with glass sand was determined to be 2.2 kg/dm3.

Investigation of Thermal Insulation Materials Based on Easy Renewable Row Materials from Agriculture

2011 ◽  
Vol 335-336 ◽  
pp. 1412-1417 ◽  
Author(s):  
Jiri Zach ◽  
Jitka Peterková ◽  
Vít Petranek ◽  
Jana Kosíková ◽  
Azra Korjenic
Keyword(s):  
Thermal Insulation ◽  
Building Materials ◽  
Raw Materials ◽  
Building Construction ◽  
Materials Development ◽  
Insulation Materials ◽  
Thermal Insulating ◽  
Plastic Materials ◽  
Energy Consuming ◽  
Rock Wool

Production of building materials is mostly energy consuming. In the sphere of insulation materials we mostly see rock wool based materials or foam-plastic materials whose production process is demanding from material aspect and raw materials aspect as well. At present the demand for thermal insulation materials has been growing globally. The thermal insulation materials form integral part of all constructions in civil engineering. The materials mainly fulfill the thermal insulating functions and also the sound-insulating one. The majority of thermal insulation materials are able to fulfill both of the functions simultaneously. The paper describes questions of thermal insulation materials development with good sound properties based on natural fibres that represent a quickly renewable source of raw materials coming from agriculture. The main advantage of the materials are mainly the local availability and simple renewability of the raw materials. In addition an easy recycling of the materials after their service life end in the building construction and last but not least also the connection of human friendly properties of organic materials with advanced product manufacture qualities of modern insulation materials.

scholarly journals AERATED CONCRETE MICROWAVE REFLECTION AND TRANSMISSION PROPERTIES IN A WET ENVIRONMENT

2017 ◽  
Vol 3 ◽  
pp. 145
Author(s):  
Tarmo Koppel ◽  
Inese Vilcane ◽  
Viktor Mironov ◽  
Andrei Shiskin ◽  
Sanita Rubene ◽  
...  
Keyword(s):  
Water Content ◽  
Transmission Loss ◽  
Base Station ◽  
Microwave Propagation ◽  
Reflection And Transmission ◽  
Excess Water ◽  
Base Station Antennas ◽  
Mobile Phone Base Station ◽  
Aerated Concrete ◽  
Wetting Process

Excess water content within the building material could greatly alter the interaction of the microwave with the material. In this study aerated concrete (AEROC) block walls (60x60cm) were investigated for their microwave (2.4 GHz) properties under wetting conditions. The spray wetting of the wall was conducted to simulate the environmental processes such as raining or water damage. 50ml/m² water dosage was applied on the surface of the concrete 21 times in 1 min intervals. The results show a noticeable decrease in microwave penetration power through the material after the sample gets enriched with water. As the water content on the surface of the material rises, so does the transmission loss. During the different water content of the aerated concrete, the reflection loss varied from -15.04 dB (dry wall) to -5.03 dB (wet wall’s surface). The transmission loss continues to rise during the entire length of the experiment, from -4.5 dB as a dry sample to -8.3 dB after 441 ml (1035 ml/m² during 23 min) of sprayed water. The variation of reflected microwave power was approximately ten times, which is quite a significant indicator of alteration of microwave propagation. The results demonstrate wetting process as an considerable factor in assessing microwave propagation in near the sources, such as mobile phone base station antennas, industrial microwave heaters and ovens etc.

Bamboo Utilization as a Sustainable Building Material

2021 ◽  
pp. 79-96
Author(s):  
Paul C. Okonkwo ◽  
Israr Ul Hassan ◽  
Wesam H. Beitelmal
Keyword(s):  
Government Policy ◽  
Building Material ◽  
Building Materials ◽  
Industrial Revolution ◽  
Environmentally Friendly ◽  
Building Design ◽  
Global Market ◽  
Building Construction ◽  
Sustainable Building ◽  
Sustainable Environment

The extraction of building materials from their resources through harvesting, preservation, and utilization has become a significant segment of human contribution to the global ecosystem since the industrial revolution. Bamboo is the world's fastest-growing woody plant, and bamboo grows multiple times quicker than most species. Housing is one of the focused demands for bamboo, and as a result of the current scarcity of home units, the demand for bamboo is increasing. Bamboo building construction is portrayed by a basic edge approach like that applied in traditional building design and construction. Applying bamboo as an environmentally friendly material is seen as a movement towards creating a sustainable environment and reducing greenhouse emissions. The need to employ government policy in addressing the production and application of bamboo is reported, and the challenges of bamboo in the global market are highlighted in this chapter.

scholarly journals A Novel Method for nZEB Internal Coverings Design Based on Neural Networks

Coatings ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 288 ◽  
Author(s):  
José A. Orosa ◽  
Diego Vergara ◽  
Ángel M. Costa ◽  
Rebeca Bouzón
Keyword(s):  
Building Materials ◽  
International Energy Agency ◽  
Construction Materials ◽  
Real Data ◽  
Point Of View ◽  
Building Construction ◽  
Sampled Data ◽  
Energy Agency ◽  
Vapour Permeability ◽  
Weather Changes

Research from the International Energy Agency about indoor ambiences and nearly zero energy buildings (nZEB) in the past has been centred on different aspects such as the prediction of indoor conditions as a function of the weather using laboratory material properties for simulations and real sampled data for validation. Thus, it is possible to use real data for defining behavioural groups of indoor ambiences as a function of real vapour permeability of internal coverings. However, this method is not suitable for modelling it and predicting its behaviour under weather changes, which is of interest to improve the method of selection and use of building construction materials. In this research, artificial intelligence procedures were employed as the first model of permeable coverings material behaviour to provide a newer understanding of building materials and applications for the generation of new control procedures between the mechanical and electronic point of view of building construction materials.

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