THEORETICAL APPROACH TO DETERMINATION OF ACOUSTIC PROPERTIES OF BUILDING MATERIALS

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Lukáš Fiala ◽  
Robert Černý
Keyword(s):  
Theoretical Approach ◽  
Urban Areas ◽  
Building Materials ◽  
Construction Materials ◽  
Well Being ◽  
Acoustic Properties ◽  
Solid Matrix ◽  
Sound Waves ◽  
Acoustic Load

The presence of high level of acoustic load especially in urban areas is becoming a serious problem in the present. In order to protect people against adverse effects of audio noise on health and personal well-being in buildings located in such areas, convenient construction materials with sophisticated geometric arrangement should be used. Bearing structures of new houses in the Czech Republic are widely made of different types of brick blocks. Such brick blocks consist of solid matrix and cavities designed in an optimized geometrical way in order to assure better thermal and hygric properties. Previous studies dealing both with acoustic properties in an empirical way and with the theoretical aspects of acoustic attenuation in building materials were not very numerous. Nevertheless, they gain constantly in importance with increasing acoustic load of the buildings surroundings. In this paper, a theoretical approach for the determination of acoustic properties, which is convenient for the description of sound waves propagation in building materials, is introduced.

EXPERIMENTAL DETERMINATION OF ACOUSTIC BEHAVIOR OF BUILDING MATERIALS BY MEANS OF ACCELEROMETERIC MEASUREMENTS

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Lukáš Fiala ◽  
Petr Konrád ◽  
Robert Černý
Keyword(s):  
Experimental Determination ◽  
Urban Areas ◽  
Building Materials ◽  
Acoustic Properties ◽  
Traffic Load ◽  
Acoustic Behavior ◽  
Frequency Range ◽  
Acoustic Performance ◽  
Acoustic Load

In Central Europe, brick blocks with incorporated system of voids ensuring good thermal properties are widely used in the building industry. In the present, increasingly higher acoustic load gains on importance especially in the surroundings of places with high traffic load, places close to the airports or in urban areas. This fact should be taken into consideration in the design of constructions in order to ensure their good acoustic performance. The very first step of such design lies in the experimental determination of acoustic properties of the reference construction elements which are, if necessary, subsequently optimized by adjustment of the voids volume and geometry or filling of the voids by various bulk fillers ensuring a higher level of scattering of the propagating acoustic signal. In this paper, steel prism and brick block were subjected to measurements by accelerometers in the frequency range 1 – 10 kHz in order to compare acoustic behavior of materials with a significantly different structure. Finally, frequency-dependent displacements in accelerometers position,

scholarly journals Sound-Absorbing Acoustic Concretes: A Review

2021 ◽  
Vol 13 (19) ◽  
pp. 10712 ◽  
Author(s):  
Mugahed Amran ◽  
Roman Fediuk ◽  
Gunasekaran Murali ◽  
Nikolai Vatin ◽  
Amin Al-Fakih
Keyword(s):  
Building Materials ◽  
Measurement Techniques ◽  
Construction Materials ◽  
Residential Building ◽  
Well Being ◽  
Acoustic Properties ◽  
Sound Insulation ◽  
Absorption Properties ◽  
Acoustic Performance ◽  
Cellular Concrete

Noise is continuously treated as an annoyance to humans and indeed commotion contamination shows up within the environment, causing inconvenience. This is likewise interesting to the engineering tactic that inclines to develop this noise proliferation. The basics of the sound-retaining proliferation, sound-absorbing properties, and its variables were rarely considered by previous researchers. Thus, the acoustic performance and sound insulation of constructions have gained significance over the last five decades due to the trend for accommodating inner-city flat and multi-story residential building condominiums. Due to this dilemma, the proliferation of high-driven entertaining schemes has engaged extraordinary demands on building for its acoustic performance. Yet, construction industries worldwide have started to mainly use sound-absorbing concrete to reduce the frequency of sounds in opened-and-closed areas and increase sound insulation. As reported, the concrete acoustic properties generally rely on its density, exhibiting that the lighter ones, such as cellular concrete, will absorb more sound than high-density concretes. However, this paper has an objective to afford a wide-ranging review of sound-absorbing acoustic concretes, including the measurement techniques and insulation characteristics of building materials and the sound absorption properties of construction materials. It is also intended to extensively review to provide insights into the possible use of a typical sound-absorbing acoustic concrete in today’s building industry to enhance housing occupants’ efficiency, comfort, well-being, and safety.

scholarly journals Methods for determination of acoustic properties of building materials

2019 ◽  
Vol 282 ◽  
pp. 02061
Author(s):  
Lukáš Fiala ◽  
Petr Konrád ◽  
Robert Černý
Keyword(s):  
Urban Areas ◽  
Building Materials ◽  
Heavy Traffic ◽  
Harmonic Signal ◽  
Steel Sample ◽  
Acoustic Properties ◽  
Acoustic Insulation ◽  
Reverberation Chambers ◽  
High Level

Experimental determination of acoustic properties of building materials is an important task gaining higher importance due to demand for materials suitable for constructions located in places with high level of noise, typically in urban areas and places close to the areas with heavy traffic. In this paper, two types of experimental setups are arranged, and tested on steel prism and brick block. Transmitter-receiver method is based on exciting the tested material by one period of harmonic signal and analysis of response on two accelerometers placed on the excited and the opposite side of the sample. The second method is based on measurement of the sound pressure level in a system of two reverberation chambers by precise microphones and vibration analyzer. Transmitter-receiver measurement conducted on steel sample revealed the fact that further adjustment of the measurement setup and successive analysis is necessary. Measurement in reverberation chambers is convenient for comparison of acoustic insulation ability of heterogeneous building materials.

scholarly journals The Use of Reftinskaya State District Power Plant Fly Ash in the Production of Building Materials and Products

2020 ◽  
Author(s):  
Fedor Kapustin ◽  
Vladislav Ufimtsev ◽  
Andrey Vishnevsky ◽  
Irina Fomina ◽  
Alexey Kapustin ◽  
...  
Keyword(s):  
Fly Ash ◽  
Power Plant ◽  
Building Materials ◽  
Natural Radionuclides ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Slag Removal ◽  
Ash Removal ◽  
Composition Properties

The system of dry ash–slag removal at the Reftinskaya state district power plant which provides capture, storage and shipment of fly ash to the consumers is considered in this study. The results of determination of chemical and phase composition, physical properties, melting temperature and activity of natural radionuclides of ash which is form during burning of stone coal of Ekibastuz basin are presented. Ash is acidic, superfine and refractory one with a low content of combustible substance. As to composition and properties it satisfies the requirements of Russian Standard no. 25818 and ships to consumers under Technical Conditions 5717–004–79935691–2009. The results of laboratory tests and industrial production of building materials and products on the basis of ash of Reftinskaya state district power plant are presented. It is shown that ash is used in the production of Portland cement, heavy and cellular autoclave concrete, dry mixes and can also be used as part of fly ash non-fired and agloporite gravel, ceramic bricks. The features of their production, basic physical and mechanical properties of building materials and products are described. It is shown that the introduction of a new system of dry ash removal at the state district power plant contributes to the expansion of directions and increase in the volume of ash recycling. Keywords: Reftinskaya state district power plant, dry ash removal, fly ash, composition, properties, use, construction materials and products

Utilization of Materials from the Production of Mineral Wool into Construction Materials

2014 ◽  
Vol 1000 ◽  
pp. 178-181
Author(s):  
Pavel Leber ◽  
René Čechmánek ◽  
Petr Bibora ◽  
Ivana Chromková ◽  
Martin Vyvážil
Keyword(s):  
Building Materials ◽  
Construction Materials ◽  
Mineral Wool ◽  
Fibre Reinforced Concrete ◽  
Concrete Blocks ◽  
Negative Effect ◽  
Glass Fibre Reinforced ◽  
Thin Walled ◽  
Material Utilization

This paper describes research on utilization of solid waste materials from mineral wool production. Aim of this research is verification of most suitable way of separated waste material utilization in building materials and determination of its maximal amount without negative effect on physical-mechanical and ecological characteristics of a final product. The research was focused on self-leveling mixtures, thin-walled glass fibre reinforced concrete products and vibropressed thin-walled shaped concrete blocks.

scholarly journals On the importance of desiccant during the determination of water vapor permeability of permeable insulation material

2020 ◽  
Vol 172 ◽  
pp. 14003
Author(s):  
Thibaut Colinart ◽  
Patrick Glouannec
Keyword(s):  
Water Vapor ◽  
Building Materials ◽  
Wood Fiber ◽  
Construction Materials ◽  
Water Vapor Permeability ◽  
Vapor Permeability ◽  
Diffusion Resistance ◽  
Insulation Material ◽  
The Impact

Water vapor permeability of building materials is usually measured using dry cup test according to the ISO 12572 standard. For this test, suitable adsorbing desiccant should be used to provide stable low vapor pressure conditions within the cup and, thus, to ensure the good accuracy of the measurement. In this work, different adsorbing desiccants mentioned in the ISO 12572 standard are tested for measurements performed on wood fiber insulation. For each experiment, relative humidity is monitored inside the dry cup. The results indicate that 0 %RH is not reached inside the dry cup and boundary condition is not always stable for highly permeable construction materials, depending on the adsorbing desiccants. The impact of these observation is evaluated on the determination of water vapor diffusion resistance factor and compared to other sources of uncertainties.

THE FACTORS OF CAREER SELF-DETERMINATION OF STUDENTS OF HIGHER EDUCATION INSTITUTIONS

2019 ◽  
Vol 7 (1) ◽  
pp. 9-20
Author(s):  
Inna Yeung
Keyword(s):  
Higher Education ◽  
Higher Education Institutions ◽  
Well Being ◽  
Young Person ◽  
Self Determination ◽  
Full Time ◽  
Actual Problem ◽  
The Third ◽  
The Right

Choice of profession is a social phenomenon that every person has to face in life. Numerous studies convince us that not only the well-being of a person depends on the chosen work, but also his attitude to himself and life in general, therefore, the right and timely professional choice is very important. Research about factors of career self-determination of students of higher education institutions in Ukraine shows that self-determination is an important factor in the socialization of young person, and the factors that determine students' career choices become an actual problem of nowadays. The present study involved full-time and part-time students of Institute of Philology and Mass Communications of Open International University of Human Development "Ukraine" in order to examine the factors of career self-determination of students of higher education institutions (N=189). Diagnostic factors of career self-determination of students studying in the third and fourth year were carried out using the author's questionnaire. Processing of obtained data was carried out using the Excel 2010 program; factorial and comparative analysis were applied. Results of the study showed that initial stage of career self-determination falls down on the third and fourth studying year at the university, when an image of future career and career orientations begin to form. At the same time, the content of career self-determination in this period is contradictory and uncertain, therefore, the implementation of pedagogical support of this process among students is effective.

Polypeptides Folding: Rules for the Calculation of the Backbone Dihedral Angles φ starting from the Amino Acid Sequence

2020 ◽  
Author(s):  
Michele Larocca
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Theoretical Approach ◽  
Polypeptide Chain ◽  
Hydrophobic Effect ◽  
Side Chain ◽  
Dihedral Angles ◽  
Mechanical Forces ◽  
Specific Chemical

<p>Protein folding is strictly related to the determination of the backbone dihedral angles and depends on the information contained in the amino acid sequence as well as on the hydrophobic effect. To date, the type of information embedded in the amino acid sequence has not yet been revealed. The present study deals with these problematics and aims to furnish a possible explanation of the information contained in the amino acid sequence, showing and reporting rules to calculate the backbone dihedral angles φ. The study is based on the development of mechanical forces once specific chemical interactions are established among the side chain of the residues in a polypeptide chain. It aims to furnish a theoretical approach to predict backbone dihedral angles which, in the future, may be applied to computational developments focused on the prediction of polypeptide structures.</p>

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