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Journal & Issues

Volume 16 (2021): Issue 2 (December 2021)

Volume 16 (2021): Issue 1 (June 2021)

Volume 15 (2020): Issue 2 (December 2020)

Volume 15 (2020): Issue 1 (September 2020)

Volume 14 (2019): Issue 2 (December 2019)

Volume 14 (2019): Issue 1 (December 2019)

Volume 13 (2018): Issue s1 (March 2018)
Special Issue

Volume 13 (2018): Issue 1 (December 2018)

Volume 12 (2017): Issue 2 (December 2017)

Volume 12 (2017): Issue 1 (June 2017)

Volume 11 (2016): Issue 2 (December 2016)

Volume 11 (2016): Issue 1 (June 2016)

Volume 10 (2015): Issue 2 (November 2015)

Volume 10 (2015): Issue 1 (June 2015)

Volume 9 (2014): Issue 2 (November 2014)

Volume 9 (2014): Issue 1 (June 2014)

Volume 8 (2013): Issue 2 (November 2013)

Volume 8 (2013): Issue 1 (June 2013)

Volume 7 (2012): Issue 2 (November 2012)

Volume 7 (2012): Issue 1 (June 2012)

Journal Details
Format
Journal
eISSN
1338-7278
First Published
29 Mar 2013
Publication timeframe
2 times per year
Languages
English

Search

Volume 11 (2016): Issue 1 (June 2016)

Journal Details
Format
Journal
eISSN
1338-7278
First Published
29 Mar 2013
Publication timeframe
2 times per year
Languages
English

Search

13 Articles
access type Open Access

Theoretical and experimental investigations of thermal conditions of household biogas plant

Published Online: 27 Jul 2016
Page range: 7 - 14

Abstract

Abstract

The construction of domestic continuous bioreactor is proposed. The modeling of thermal modes of household biogas plant using graph theory was done. The correction factor taking into account with the influence of variables on its value was determined. The system of balance equations for the desired thermal conditions in the bioreactor was presented.

The graphical and analytical capabilities were represented that can be applied in the design of domestic biogas plants of organic waste recycling.

Keywords

  • bioreactor
  • biogas
  • methane fermentation
  • organic waste
  • anaerobic fermentation
access type Open Access

Preparation and characterization of glass fibers – polymers (epoxy) bars (GFRP) reinforced concrete for structural applications

Published Online: 27 Jul 2016
Page range: 15 - 22

Abstract

Abstract

The paper presents some of the results from a large experimental program undertaken at the Department of Civil Engineering of Damascus University. The project aims to study the ability to reinforce and strengthen the concrete by bars from Epoxy polymer reinforced with glass fibers (GFRP) and compared with reinforce concrete by steel bars in terms of mechanical properties. Five diameters of GFRP bars, and steel bars (4mm, 6mm, 8mm, 10mm, 12mm) tested on tensile strength tests. The test shown that GFRP bars need tensile strength more than steel bars. The concrete beams measuring (15cm wide × 15cm deep × and 70cm long) reinforced by GFRP with 0.5 vol.% ratio, then the concrete beams reinforced by steel with 0.89 vol.% ratio. The concrete beams tested on deflection test. The test shown that beams which reinforced by GFRP has higher deflection resistance, than beams which reinforced by steel. Which give more advantage to reinforced concrete by GFRP.

Keywords

  • GFRP bars
  • steel bars
  • tensile strength
  • deflection
access type Open Access

Use of communication technologies in document exchange for the management of construction projects

Published Online: 27 Jul 2016
Page range: 23 - 30

Abstract

Abstract

Information and communication technologies represent a set of people, processes, technical and software tools providing collection, transport, storage and processing of data for distribution and presentation of information. Particularly communication systems are the main tool for information exchange. Of the other part, these technologies have a broad focus and use. One of them is the exchange of documents in the management of construction projects. Paper discusses the issue of exploitation level of communication technologies in construction project management. The main objective of this paper is to analyze exploitation level of communication technologies. Another aim of the paper is to compare exploitation level or rate of document exchange by electronic communication devices and face-to-face communication.

Keywords

  • information and communication technologies
  • document exchange
  • construction project management
access type Open Access

Monitoring of water quality of selected wells in Brno district

Published Online: 27 Jul 2016
Page range: 31 - 40

Abstract

Abstract

The article deals with two wells in the country of Brno-district (Brčálka well and Well Olšová). The aim of work was monitoring of elementary parameters of water at regular monthly intervals to measure: water temperature, pH values, solubility oxygen and spring yield. According to the client's requirements (Lesy města Brno) laboratory analyzes of selected parameters were done twice a year and their results were compared with Ministry of Health Decree no. 252/2004 Coll.. These parameters: nitrate, chemical oxygen demand (COD), calcium and magnesium and its values are presented in graphs, for ammonium ions and nitrite in the table. Graphical interpretation of spring yields dependence on the monthly total rainfall and dependence of water temperature on ambient temperature was utilized. The most important features of wells include a water source, a landmark in the landscape, aesthetic element or resting and relaxing place. Maintaining wells is important in terms of future generations.

Keywords

  • COD
  • pH values
  • spring yield
  • water temperature
  • well
access type Open Access

Modifying the properties of finely ground limestone by tumbling granulation

Published Online: 27 Jul 2016
Page range: 41 - 50

Abstract

Abstract

Calcium carbonate in the form of finely ground limestone is a material that has found its application in a wide range of industries, in the chemical, rubber, agricultural, and paper industries, is used for desulfurization of boilers and other. In civil engineering, ground limestone is used for the production of building materials, plaster and mortar mixtures, as a filler in concrete mixtures, in road construction, and as an essential component of mastic asphalt. This paper deals with examining the modification of the properties of finely ground limestone by the tumbling agglomeration method. It has been shown that the components of concrete with a round grain have a positive effect on the pumping of concrete in comparison with an elongated grain or the rough surface of crushed stone. The experiments will be carried out on a granulation plate using a variety of granulation liquid. The agglomerates and their properties were compared with untreated finely ground limestone, with a focus on detecting changes in compressibility, density and particle size. The output of this paper is a description and graphical representation of the changes in the properties of ground limestone before and after the agglomeration process.

Keywords

  • ground limestone
  • agglomeration
  • compressibility
  • flow properties
access type Open Access

Verification of the thermal insulation properties and determination the optimal position of the reflective thermal insulation layer in the wood based envelope

Published Online: 27 Jul 2016
Page range: 51 - 58

Abstract

Abstract

To achieve thinner wood based envelope is necessary look for an alternative thermal insulation material, which will have the best possible thermal insulation properties while maintaining affordability. One such material is also reflective thermal insulation layer, but it is necessary to verify the thermal insulation properties and determine the optimal position in the wood based envelope.

Keywords

  • reflective thermal insulation layer
  • experimental measurements in climate chambers
  • the optimal position
  • thermal resistance
access type Open Access

The HEC RAS model of regulated stream for purposes of flood risk reduction

Published Online: 27 Jul 2016
Page range: 59 - 70

Abstract

Abstract

The work highlights the modeling of water flow in open channels using 1D mathematical model HEC-RAS in the area of interest Lopuchov village in eastern Slovakia. We created a digital model from a geodetic survey, which was used to show the area of inundation in ArcGIS software. We point out the modeling methodology with emphasis to collection of the data and their relevance for determination of boundary conditions in 3D model of the study area in GIS platform. The BIM objects can be exported to the defined model of the area. The obtained results were used for simulation of flooding. The results give to us clearly and distinctly defined areas of inundation, which we used in the processing of Cost benefit analysis. We used the developed model for stating the potential damages in flood vulnerable areas.

Keywords

  • HEC-RAS
  • mathematical modeling
  • BIM technologies
  • GIS
access type Open Access

Detail in architecture: Between arts & crafts

Published Online: 27 Jul 2016
Page range: 71 - 76

Abstract

Abstract

Architectural detail represents an important part of architecture. Not only can it be used as an identifier of a specific building but at the same time enhances the experience of the realized project. Within it lie the signs of a great architect and clues to understanding his or her way of thinking. It is therefore the central topic of a seminar offered to architecture students at the Brno University of Technology. During the course of the semester-long class the students acquaint themselves with atypical architectural details of domestic and international architects by learning to read them, understand them and subsequently draw them by creating architectural blueprints. In other words, by general analysis of a detail the students learn theoretical thinking of its architect who, depending on the nature of the design, had to incorporate a variety of techniques and crafts. Students apply this analytical part to their own architectural detail design. The methodology of the seminar consists of experiential learning by project management and is complemented by a series of lectures discussing a diversity of details as well as materials and technologies required to implement it. The architectural detail design is also part of students’ bachelors thesis, therefore, the realistic nature of their blueprints can be verified in the production process of its physical counterpart. Based on their own documentation the students choose the most suitable manufacturing process whether it is supplied by a specific technology or a craftsman. Students actively participate in the production and correct their design proposals in real scale with the actual material. A student, as a future architect, stands somewhere between a client and an artisan, materializes his or her idea and adjusts the manufacturing process so that the final detail fulfills aesthetic consistency and is in harmony with its initial concept. One of the very important aspects of the design is its economic cost, an actual price of real implementation. The detail determines not only the physical expression, it becomes the characteristic feature from which the rest of the building is derived. This course motivates students to surpass mere technical calculations learned from books towards sophistication and refinement, pragmatism and experimentation, and encourages a shift from feasibility to perfection.

Keywords

  • detail
  • architecture
  • arts & crafts
access type Open Access

In situ monitoring of internal surface temperature of the historic building envelope

Published Online: 27 Jul 2016
Page range: 77 - 84

Abstract

Abstract

Historical building envelope is characterized by a large accumulation that impact is mainly by changing the inner surface temperature over time. The minimum value of the inner surface temperature is set Code requirements. In the case of thermal technology assessment of building envelope contemplates a steady state external temperature and internal environment, thereby neglecting the heat accumulation capacity of building envelopes. Monitoring surface temperature in real terms in situ shows the real behavior of the building envelope close to reality. The recorded data can be used to create a numerical model for the simulation.

Keywords

  • inner surface temperature
  • simulation
  • historical building envelope
access type Open Access

European tendencies and co-operation in the field of ITS systems - national achievements and challenges in Hungary

Published Online: 27 Jul 2016
Page range: 85 - 96

Abstract

Abstract

The article presents the role of intelligent transport systems/services related to the implementation of the essential European and Hungarian transport policy objectives. The ‘ITS Directive’ will provide a framework for the tasks/works to be performed in the forthcoming years within the priority areas of ITS. The European Commission published regulations / specifications for the priority actions in the form of delegated acts defining the tasks/responsibilities of Member States. Regional/European co-operation for Hungary started after the EU-accession of the country. Hungary was an active partner within the European CONNECT and EasyWay projects, currently Hungary is a member of the CROCODILE consortium.

Keywords

  • National Transport Policy
  • ITS Directive
  • ITS strategy
  • specifications/regulations
  • regional/European co-operation
access type Open Access

The importance of the criteria of residential buildings from the perspective of future users

Published Online: 27 Jul 2016
Page range: 97 - 106

Abstract

Abstract

The developers need to know what is important to their customers in preparation of new construction of residential buildings. The paper deals with finding the importance of structure, material, cost, time and environmental criteria of residential buildings from the perspective of the future owners. The research methodology that provided the information was questionnaire survey. Research was conducted in two lines. The first line is dedicated to the research of main construction domains of residential building. The second line of the research deals with the specific criteria of main construction domains. The order of importance of the main areas and the specific criteria is determined by analyzing of data through descriptive characteristics: median, modus, variance, average value and by weigh of importance.

Keywords

  • residential building
  • structure criteria
  • user perception
access type Open Access

Determination of VOCs in the Indoor Air of a New and a Renovated Apartment

Published Online: 27 Jul 2016
Page range: 107 - 118

Abstract

Abstract

This study deals with the occurrence of volatile organic compounds (VOCs) in the indoor environment of a new and a renovated apartment. Qualitative determination of VOCs was carried out with a gas chromatograph with surface acoustic wave detector (GC/SAW). Concentrations of total volatile organic compounds (TVOC) were determined by a photoionization detector with UV lamp. Simultaneously, temperature and relative humidity were monitored with a data logger. The aim of this study was to determine of TVOC concentrations, to use of GC/SAW for determination of individual VOCs in indoor air as well as to predict possible sources of VOCs in these apartments. Measurements were performed after each construction work for better resolution of the contributions of individual materials to the levels of VOC. Mean concentrations of TVOC were 624 μg/m3 in the renovated apartment and 1,686 μg/m3 in the new apartment after completion of all works. The results from the renovated apartment showed that the use of new materials can lead to lower levels of organic compounds in indoor air compared to old materials that were less environmentally friendly. Many types of VOCs were found in both apartments. After reviewing the possible sources, it seems that the main sources of these substances were applied coatings and flooring materials.

Keywords

  • indoor air
  • apartments
  • volatile organic compounds
  • GC/SAW
  • material emissions
access type Open Access

Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

Published Online: 27 Jul 2016
Page range: 119 - 130

Abstract

Abstract

This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering “Nominal the better” situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

Keywords

  • Fly ash
  • M-sand
  • Spent foundry sand
  • Self compacting concrete
  • Modified Nan Su method
  • Taguchi approach
  • Signal to noise ratio
  • Optimal mix proportion
13 Articles
access type Open Access

Theoretical and experimental investigations of thermal conditions of household biogas plant

Published Online: 27 Jul 2016
Page range: 7 - 14

Abstract

Abstract

The construction of domestic continuous bioreactor is proposed. The modeling of thermal modes of household biogas plant using graph theory was done. The correction factor taking into account with the influence of variables on its value was determined. The system of balance equations for the desired thermal conditions in the bioreactor was presented.

The graphical and analytical capabilities were represented that can be applied in the design of domestic biogas plants of organic waste recycling.

Keywords

  • bioreactor
  • biogas
  • methane fermentation
  • organic waste
  • anaerobic fermentation
access type Open Access

Preparation and characterization of glass fibers – polymers (epoxy) bars (GFRP) reinforced concrete for structural applications

Published Online: 27 Jul 2016
Page range: 15 - 22

Abstract

Abstract

The paper presents some of the results from a large experimental program undertaken at the Department of Civil Engineering of Damascus University. The project aims to study the ability to reinforce and strengthen the concrete by bars from Epoxy polymer reinforced with glass fibers (GFRP) and compared with reinforce concrete by steel bars in terms of mechanical properties. Five diameters of GFRP bars, and steel bars (4mm, 6mm, 8mm, 10mm, 12mm) tested on tensile strength tests. The test shown that GFRP bars need tensile strength more than steel bars. The concrete beams measuring (15cm wide × 15cm deep × and 70cm long) reinforced by GFRP with 0.5 vol.% ratio, then the concrete beams reinforced by steel with 0.89 vol.% ratio. The concrete beams tested on deflection test. The test shown that beams which reinforced by GFRP has higher deflection resistance, than beams which reinforced by steel. Which give more advantage to reinforced concrete by GFRP.

Keywords

  • GFRP bars
  • steel bars
  • tensile strength
  • deflection
access type Open Access

Use of communication technologies in document exchange for the management of construction projects

Published Online: 27 Jul 2016
Page range: 23 - 30

Abstract

Abstract

Information and communication technologies represent a set of people, processes, technical and software tools providing collection, transport, storage and processing of data for distribution and presentation of information. Particularly communication systems are the main tool for information exchange. Of the other part, these technologies have a broad focus and use. One of them is the exchange of documents in the management of construction projects. Paper discusses the issue of exploitation level of communication technologies in construction project management. The main objective of this paper is to analyze exploitation level of communication technologies. Another aim of the paper is to compare exploitation level or rate of document exchange by electronic communication devices and face-to-face communication.

Keywords

  • information and communication technologies
  • document exchange
  • construction project management
access type Open Access

Monitoring of water quality of selected wells in Brno district

Published Online: 27 Jul 2016
Page range: 31 - 40

Abstract

Abstract

The article deals with two wells in the country of Brno-district (Brčálka well and Well Olšová). The aim of work was monitoring of elementary parameters of water at regular monthly intervals to measure: water temperature, pH values, solubility oxygen and spring yield. According to the client's requirements (Lesy města Brno) laboratory analyzes of selected parameters were done twice a year and their results were compared with Ministry of Health Decree no. 252/2004 Coll.. These parameters: nitrate, chemical oxygen demand (COD), calcium and magnesium and its values are presented in graphs, for ammonium ions and nitrite in the table. Graphical interpretation of spring yields dependence on the monthly total rainfall and dependence of water temperature on ambient temperature was utilized. The most important features of wells include a water source, a landmark in the landscape, aesthetic element or resting and relaxing place. Maintaining wells is important in terms of future generations.

Keywords

  • COD
  • pH values
  • spring yield
  • water temperature
  • well
access type Open Access

Modifying the properties of finely ground limestone by tumbling granulation

Published Online: 27 Jul 2016
Page range: 41 - 50

Abstract

Abstract

Calcium carbonate in the form of finely ground limestone is a material that has found its application in a wide range of industries, in the chemical, rubber, agricultural, and paper industries, is used for desulfurization of boilers and other. In civil engineering, ground limestone is used for the production of building materials, plaster and mortar mixtures, as a filler in concrete mixtures, in road construction, and as an essential component of mastic asphalt. This paper deals with examining the modification of the properties of finely ground limestone by the tumbling agglomeration method. It has been shown that the components of concrete with a round grain have a positive effect on the pumping of concrete in comparison with an elongated grain or the rough surface of crushed stone. The experiments will be carried out on a granulation plate using a variety of granulation liquid. The agglomerates and their properties were compared with untreated finely ground limestone, with a focus on detecting changes in compressibility, density and particle size. The output of this paper is a description and graphical representation of the changes in the properties of ground limestone before and after the agglomeration process.

Keywords

  • ground limestone
  • agglomeration
  • compressibility
  • flow properties
access type Open Access

Verification of the thermal insulation properties and determination the optimal position of the reflective thermal insulation layer in the wood based envelope

Published Online: 27 Jul 2016
Page range: 51 - 58

Abstract

Abstract

To achieve thinner wood based envelope is necessary look for an alternative thermal insulation material, which will have the best possible thermal insulation properties while maintaining affordability. One such material is also reflective thermal insulation layer, but it is necessary to verify the thermal insulation properties and determine the optimal position in the wood based envelope.

Keywords

  • reflective thermal insulation layer
  • experimental measurements in climate chambers
  • the optimal position
  • thermal resistance
access type Open Access

The HEC RAS model of regulated stream for purposes of flood risk reduction

Published Online: 27 Jul 2016
Page range: 59 - 70

Abstract

Abstract

The work highlights the modeling of water flow in open channels using 1D mathematical model HEC-RAS in the area of interest Lopuchov village in eastern Slovakia. We created a digital model from a geodetic survey, which was used to show the area of inundation in ArcGIS software. We point out the modeling methodology with emphasis to collection of the data and their relevance for determination of boundary conditions in 3D model of the study area in GIS platform. The BIM objects can be exported to the defined model of the area. The obtained results were used for simulation of flooding. The results give to us clearly and distinctly defined areas of inundation, which we used in the processing of Cost benefit analysis. We used the developed model for stating the potential damages in flood vulnerable areas.

Keywords

  • HEC-RAS
  • mathematical modeling
  • BIM technologies
  • GIS
access type Open Access

Detail in architecture: Between arts & crafts

Published Online: 27 Jul 2016
Page range: 71 - 76

Abstract

Abstract

Architectural detail represents an important part of architecture. Not only can it be used as an identifier of a specific building but at the same time enhances the experience of the realized project. Within it lie the signs of a great architect and clues to understanding his or her way of thinking. It is therefore the central topic of a seminar offered to architecture students at the Brno University of Technology. During the course of the semester-long class the students acquaint themselves with atypical architectural details of domestic and international architects by learning to read them, understand them and subsequently draw them by creating architectural blueprints. In other words, by general analysis of a detail the students learn theoretical thinking of its architect who, depending on the nature of the design, had to incorporate a variety of techniques and crafts. Students apply this analytical part to their own architectural detail design. The methodology of the seminar consists of experiential learning by project management and is complemented by a series of lectures discussing a diversity of details as well as materials and technologies required to implement it. The architectural detail design is also part of students’ bachelors thesis, therefore, the realistic nature of their blueprints can be verified in the production process of its physical counterpart. Based on their own documentation the students choose the most suitable manufacturing process whether it is supplied by a specific technology or a craftsman. Students actively participate in the production and correct their design proposals in real scale with the actual material. A student, as a future architect, stands somewhere between a client and an artisan, materializes his or her idea and adjusts the manufacturing process so that the final detail fulfills aesthetic consistency and is in harmony with its initial concept. One of the very important aspects of the design is its economic cost, an actual price of real implementation. The detail determines not only the physical expression, it becomes the characteristic feature from which the rest of the building is derived. This course motivates students to surpass mere technical calculations learned from books towards sophistication and refinement, pragmatism and experimentation, and encourages a shift from feasibility to perfection.

Keywords

  • detail
  • architecture
  • arts & crafts
access type Open Access

In situ monitoring of internal surface temperature of the historic building envelope

Published Online: 27 Jul 2016
Page range: 77 - 84

Abstract

Abstract

Historical building envelope is characterized by a large accumulation that impact is mainly by changing the inner surface temperature over time. The minimum value of the inner surface temperature is set Code requirements. In the case of thermal technology assessment of building envelope contemplates a steady state external temperature and internal environment, thereby neglecting the heat accumulation capacity of building envelopes. Monitoring surface temperature in real terms in situ shows the real behavior of the building envelope close to reality. The recorded data can be used to create a numerical model for the simulation.

Keywords

  • inner surface temperature
  • simulation
  • historical building envelope
access type Open Access

European tendencies and co-operation in the field of ITS systems - national achievements and challenges in Hungary

Published Online: 27 Jul 2016
Page range: 85 - 96

Abstract

Abstract

The article presents the role of intelligent transport systems/services related to the implementation of the essential European and Hungarian transport policy objectives. The ‘ITS Directive’ will provide a framework for the tasks/works to be performed in the forthcoming years within the priority areas of ITS. The European Commission published regulations / specifications for the priority actions in the form of delegated acts defining the tasks/responsibilities of Member States. Regional/European co-operation for Hungary started after the EU-accession of the country. Hungary was an active partner within the European CONNECT and EasyWay projects, currently Hungary is a member of the CROCODILE consortium.

Keywords

  • National Transport Policy
  • ITS Directive
  • ITS strategy
  • specifications/regulations
  • regional/European co-operation
access type Open Access

The importance of the criteria of residential buildings from the perspective of future users

Published Online: 27 Jul 2016
Page range: 97 - 106

Abstract

Abstract

The developers need to know what is important to their customers in preparation of new construction of residential buildings. The paper deals with finding the importance of structure, material, cost, time and environmental criteria of residential buildings from the perspective of the future owners. The research methodology that provided the information was questionnaire survey. Research was conducted in two lines. The first line is dedicated to the research of main construction domains of residential building. The second line of the research deals with the specific criteria of main construction domains. The order of importance of the main areas and the specific criteria is determined by analyzing of data through descriptive characteristics: median, modus, variance, average value and by weigh of importance.

Keywords

  • residential building
  • structure criteria
  • user perception
access type Open Access

Determination of VOCs in the Indoor Air of a New and a Renovated Apartment

Published Online: 27 Jul 2016
Page range: 107 - 118

Abstract

Abstract

This study deals with the occurrence of volatile organic compounds (VOCs) in the indoor environment of a new and a renovated apartment. Qualitative determination of VOCs was carried out with a gas chromatograph with surface acoustic wave detector (GC/SAW). Concentrations of total volatile organic compounds (TVOC) were determined by a photoionization detector with UV lamp. Simultaneously, temperature and relative humidity were monitored with a data logger. The aim of this study was to determine of TVOC concentrations, to use of GC/SAW for determination of individual VOCs in indoor air as well as to predict possible sources of VOCs in these apartments. Measurements were performed after each construction work for better resolution of the contributions of individual materials to the levels of VOC. Mean concentrations of TVOC were 624 μg/m3 in the renovated apartment and 1,686 μg/m3 in the new apartment after completion of all works. The results from the renovated apartment showed that the use of new materials can lead to lower levels of organic compounds in indoor air compared to old materials that were less environmentally friendly. Many types of VOCs were found in both apartments. After reviewing the possible sources, it seems that the main sources of these substances were applied coatings and flooring materials.

Keywords

  • indoor air
  • apartments
  • volatile organic compounds
  • GC/SAW
  • material emissions
access type Open Access

Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

Published Online: 27 Jul 2016
Page range: 119 - 130

Abstract

Abstract

This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering “Nominal the better” situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

Keywords

  • Fly ash
  • M-sand
  • Spent foundry sand
  • Self compacting concrete
  • Modified Nan Su method
  • Taguchi approach
  • Signal to noise ratio
  • Optimal mix proportion

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