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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)

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

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

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

Studies on the treatment of surface water using rajma seeds

Published Online: 30 Mar 2018
Page range: 7 - 13

Abstract

Abstract

Indiscriminate disposal of wastewater with suspended solids have led to higher amount of pollution to the natural water bodies. Turbidity removal becomes an essential part in the water treatment when surface water is used for drinking purpose, this can be achieved by means of coagulation process. Coagulation process is the dosing of a coagulant in water, resulting in the destabilization of negatively charged particles. Commercial coagulants which were widely used can synthesize by-products in turn may pollute the environment and deteriorate the ecosystem at a slow rate. So, now-a-days natural coagulants are used as a potential substitute because it’s biodegradable, ecofriendly and non-toxic. In this study, the turbid surface water samples were treated using powdered seeds of Rajma (natural coagulant) followed by variations in dosage, settling time and pH were also studied. From the results obtained, it was found that the Rajma seeds powder achieved 48.80% efficiency for 0.5 g/l of optimum dose at pH 6 for 20 min settling time respectively.

Keywords

  • natural coagulant
  • turbidity
  • surface water
access type Open Access

Energy demand of occupant’s spatial modification in residential buildings. Case study of Médéa, Algeria

Published Online: 30 Mar 2018
Page range: 15 - 28

Abstract

Abstract

Housing is rated as one of the most commonly consuming energy field in terms of energy end-use with 41%. Regarding the transformations dealt by dwellers for functional and social uses. The aim of this paper is: Firstly, to highlight the non-controlled transformation process made by the occupant in Algeria; Secondly, to explore the impact of the energy load of such spatial transformations. The question is approached in two tracks, (i) Through Ecotect software’s simulations (ii) and measurements through a collection of energy end-use data. Basically, the energy demand is bound to dwelling’s spatial and socioeconomic criteria. Three cases studied showed consequently 2 positive and 1 negative energy load, in which two explanations may be given: Insulation quality that occupant is lacking facilities to improve may be stated as a physical explanation, as well as for the socio economic one, the density per dwelling plays a major role, but it is the income which explains within the two approaches more than 87% of the energy end use.

Keywords

  • Energy load
  • occupant
  • dwelling modifications
  • simulations
  • Greenhouse Gas Emission
access type Open Access

Possibilities of the fish pass restoration

Published Online: 30 Mar 2018
Page range: 29 - 36

Abstract

Abstract

According to the new elaborated methodology of the Ministry of Environment of the Slovak Republic: Identification of the appropriate fish pass types according to water body typology (2015) each barrier on the river must be passable. On the barriers or structures without fish passes new ones should be design and built and on some water structures with existed but nonfunctional fish passes must be realized reconstruction or restoration of such objects. Assessment should be done in terms of the existing migratory fish fauna and hydraulic conditions. Fish fauna requirements resulting from the ichthyological research of the river section with barrier. Hydraulic conditions must than fulfil these requirements inside the fish pass body.

Keywords

  • fish pass
  • fish fauna requirements
  • hydraulic consideration
  • design parameters
access type Open Access

Synchronizing the city with human-based spaces

Published Online: 30 Mar 2018
Page range: 37 - 44

Abstract

Abstract

The paper is about to summarize the most important development tools to make the urban spaces more human friendly in Denver, Colorado. There are more needs for having more livable and sustainable areas by reducing the use of automobiles and focusing on multimodal street design. The strategies are the basic elements to make our urban spaces better and happier from The United States to Hungary

Keywords

  • America
  • new direction
  • urban design
  • public spaces
  • street life
  • communities
  • happiness
access type Open Access

Select geotechnical properties of a lime stabilized expansive soil amended with bagasse ash and coconut shell powder

Published Online: 30 Mar 2018
Page range: 45 - 60

Abstract

Abstract

Lime stabilization has been and still is one of the most preferred methods for stabilization of expansive soils. However, in the recent times, utilization of solid waste materials in soil stabilization has gained prominence as an effective means to manage wastes generated from various sources. In this work, an attempt has been made to utilize waste materials from two sources as auxiliary additives to lime in the stabilization of an expansive soil. Bagasse ash (BA), a waste by-product from the sugar industry and Coconut shell powder (CSP), a processed waste obtained from left over coconut shells of oil extraction industry were used as auxiliary additives. An expansive soil obtained from a local field was subjected to chemical, mineral, microstructural and geotechnical characterization in the laboratory and stabilized using 3% lime. The waste materials were subjected to chemical, mineral and microstructural characterization. The stabilization process was amended with four different contents viz. 0.25%, 0.5%, 1% and 2% of BA and CSP separately and the effect of the amendment was studied on the unconfined compressive strength (UCS), plasticity, swell-shrink and microstructural characteristics of the expansive soil. The results of the study indicated that BA amendment of lime stabilization performed better than CSP in improving the UCS, plasticity, swell-shrink and microstructure of the lime stabilized expansive soil.

Keywords

  • Lime Stabilization
  • Bagasse Ash
  • Coconut Shell Powder
  • Plasticity
  • Swell-Shrink
  • UCS
access type Open Access

Improved image processing of road pavement defect by infrared thermography

Published Online: 30 Mar 2018
Page range: 61 - 72

Abstract

Abstract

This paper intends to achieve improved image processing for the clear identification of defects in damaged road pavement structure using infrared thermography non-destructive testing (NDT). To that goal, 4 types of pavement specimen including internal defects were fabricated to exploit the results obtained by heating the specimens by natural light. The results showed that defects located down to a depth of 3 cm could be detected by infrared thermography NDT using the improved image processing method.

Keywords

  • infrared thermography
  • heat source from natural light
  • image processing
  • defect
  • asphalt
access type Open Access

Effects of corn cob ash on lime stabilized lateritic soil

Published Online: 30 Mar 2018
Page range: 73 - 85

Abstract

Abstract

This study assesses the effects of Corn Cob Ash (CCA) on lime-stabilized lateritic soil. Preliminary tests were carried out on the natural soil sample for purpose of identification and classification. Lime being the main stabilizing material was thoroughly mixed with the soil sample to determine the optimum lime requirement of the sample as a basis for evaluating the effects of the CCA. The optimum lime requirement was 10%. The CCA was thereafter added to the lime stabilized soil in varying proportions of 2, 4, 6, 8 and 10%. Unsoaked CBR increased from 83% at 0% CCA to highest value of 94% at 4% CCA. Unconfined Compressive Strength (UCS) values increased from 1123kN/m2 at 0% CCA to highest value of 1180kN/m2 at 4% CCA. It was therefore concluded that CCA can serve as a good complement for lime stabilization in lateritic soil.

Keywords

  • atterberg limit
  • corn cob ash
  • lateritic soil
  • lime stabilization
  • strength tests
access type Open Access

Numerical simulation of mechanical properties tests of tungsten mud waste geopolymer

Published Online: 30 Mar 2018
Page range: 87 - 94

Abstract

Abstract

Geopolymers are believed to become in the future an environmental friendly alternative for the concrete. The low CO2 emission during the production process and the possibility of ecological management of the industrial wastes are mentioned as main advantages of geopolymers. The main drawback, causing problems with application of geopolymers as a building material is the lack of the theoretical material model. Indicated problem is being solved now by the group of scientists from the Silesian University of Technology. The series of laboratory tests are carried out within the European research project REMINE. The paper introduces the numerical analyses of tungsten mud waste geopolymer samples which have been performed in the Atena software on the basis of the laboratory tests. Numerical models of bended and compressed samples of different shapes are presented in the paper. The results obtained in Atena software were compared with results obtained in Abaqus and Mafem3D software.

Keywords

  • geopolymers
  • material model
  • Atena software
  • tungsten mine waste
access type Open Access

Bond behavior of self compacting concrete

Published Online: 30 Mar 2018
Page range: 95 - 105

Abstract

Abstract

The success of an optimum design lies in the effective load transfer done by the bond forces at the steel-concrete interface. Self Compacting Concrete, is a new innovative concrete capable of filling intrinsic reinforcement and gets compacted by itself, without the need of external mechanical vibration. For this reason, it is replacing the conventional vibrated concrete in the construction industry. The present paper outlays the materials and methods adopted for attaining the self compacting concrete and describes about the bond behavior of this concrete. The bond stress-slip curve is similar in the bottom bars for both SCC and normal concrete whereas a higher bond stress and stiffness is experienced in the top and middle bars, for SCC compared to normal concrete. Also the interfacial properties revealed that the elastic modulus and micro-strength of interfacial transition zone [ITZ] were better on the both top and bottom side of horizontal steel bar in the SCC mixes than in normal vibrated concrete. The local bond strength of top bars for SCC is about 20% less than that for NC. For the bottom bars, however, the results were almost the same.

Keywords

  • Self Compacting concrete
  • Bond force
  • Transfer of stress
access type Open Access

Comparison of calculation and simulation of evacuation in real buildings

Published Online: 30 Mar 2018
Page range: 107 - 114

Abstract

Abstract

Each building must meet requirements for safe evacuation in order to prevent casualties. Therefore methods for evaluation of evacuation are used when designing buildings. In the paper, calculation methods were tested on three real buildings. The testing used methods of evacuation time calculation pursuant to Slovak standards and evacuation time calculation using the buildingExodus simulation software. If calculation methods have been suitably selected taking into account the nature of evacuation and at the same time if correct values of parameters were entered, we will be able to obtain almost identical times of evacuation in comparison with real results obtained from simulation. The difference can range from 1% to 27%.

Keywords

  • evacuation of building
  • evacuation time
  • calculation methods
  • input values
  • simulation
access type Open Access

Hydro power plants, an overview of the current types and technology

Published Online: 30 Mar 2018
Page range: 115 - 126

Abstract

Abstract

Despite the long history of hydropower technology and rising number of system harvesting energy from alternative sources, the constant research within hydro power sector becoming increasingly important as the power from water was and still is the leading alternative source of green energy generation, capitalized not necessarily within micro-urban structures only. The advantages of hydro systems involve their relatively low acquisition cost against durability, the possibility of gaining energy independence, relatively high flexibility and adaptability for spatial conditions and energy demands of the end users. Nowadays micro hydro systems could capitalize head range starting at 100cm and the efficiency of hydro systems in general ranges between 65-75% in micro and small applications climbing up to 96% in macro designs. It is mostly due to flexibility in applications, adaptability in combinations with other renewable energy systems and the ability to generate clean, stable, thus reliable energy that makes technical development the most vibrant and noticeable in the micro sphere.

Keywords

  • hydro power
  • power plant
  • renewable resources
  • water
access type Open Access

Comparison of physical and mechanical properties of river sand concrete with quarry dust concrete

Published Online: 30 Mar 2018
Page range: 127 - 134

Abstract

Abstract

This study compared the physical and mechanical properties of river sand concrete with quarry dust concrete. The constituent materials were batched by weight. The water-cement ratio and mix ratio selected for the experimental investigation were 0.55 and 1:2:4, respectively. The specimens were cured for 7, 14, 21 and 28 days. Slump, density and compressive strength tests were carried out. The results showed that river sand concrete had greater density and compressive strength than quarry dust concrete for all curing ages. At 28 days of curing, river sand concrete exceeded the target compressive strength by 36%, whereas quarry dust concrete was less than the target compressive strength by 12%. Both river sand concrete and quarry dust concrete for the selected water/cement ratio and mix ratio are suitable for non-structural applications and lightly-loaded members where high strength is not a prerequisite.

Keywords

  • density
  • compressive strength
  • concrete
  • river sand
  • quarry dust
access type Open Access

A practical approach to tramway track condition monitoring: vertical track defects detection and identification using time-frequency processing technique

Published Online: 30 Mar 2018
Page range: 135 - 146

Abstract

Abstract

This paper presents an automatic method for detecting vertical track irregularities on tramway operation using acceleration measurements on trams. For monitoring of tramway tracks, an unconventional measurement setup is developed, which records the data of 3-axes wireless accelerometers mounted on wheel discs. Accelerations are processed to obtain the vertical track irregularities to determine whether the track needs to be repaired. The automatic detection algorithm is based on time–frequency distribution analysis and determines the defect locations. Admissible limits (thresholds) are given for detecting moderate and severe defects using statistical analysis. The method was validated on frequented tram lines in Budapest and accurately detected severe defects with a hit rate of 100%, with no false alarms. The methodology is also sensitive to moderate and small rail surface defects at the low operational speed.

Keywords

  • tramway track condition monitoring
  • time-frequency signal processing
  • vibration
  • wheel-rail interaction
  • wavelet transform
13 Articles
access type Open Access

Studies on the treatment of surface water using rajma seeds

Published Online: 30 Mar 2018
Page range: 7 - 13

Abstract

Abstract

Indiscriminate disposal of wastewater with suspended solids have led to higher amount of pollution to the natural water bodies. Turbidity removal becomes an essential part in the water treatment when surface water is used for drinking purpose, this can be achieved by means of coagulation process. Coagulation process is the dosing of a coagulant in water, resulting in the destabilization of negatively charged particles. Commercial coagulants which were widely used can synthesize by-products in turn may pollute the environment and deteriorate the ecosystem at a slow rate. So, now-a-days natural coagulants are used as a potential substitute because it’s biodegradable, ecofriendly and non-toxic. In this study, the turbid surface water samples were treated using powdered seeds of Rajma (natural coagulant) followed by variations in dosage, settling time and pH were also studied. From the results obtained, it was found that the Rajma seeds powder achieved 48.80% efficiency for 0.5 g/l of optimum dose at pH 6 for 20 min settling time respectively.

Keywords

  • natural coagulant
  • turbidity
  • surface water
access type Open Access

Energy demand of occupant’s spatial modification in residential buildings. Case study of Médéa, Algeria

Published Online: 30 Mar 2018
Page range: 15 - 28

Abstract

Abstract

Housing is rated as one of the most commonly consuming energy field in terms of energy end-use with 41%. Regarding the transformations dealt by dwellers for functional and social uses. The aim of this paper is: Firstly, to highlight the non-controlled transformation process made by the occupant in Algeria; Secondly, to explore the impact of the energy load of such spatial transformations. The question is approached in two tracks, (i) Through Ecotect software’s simulations (ii) and measurements through a collection of energy end-use data. Basically, the energy demand is bound to dwelling’s spatial and socioeconomic criteria. Three cases studied showed consequently 2 positive and 1 negative energy load, in which two explanations may be given: Insulation quality that occupant is lacking facilities to improve may be stated as a physical explanation, as well as for the socio economic one, the density per dwelling plays a major role, but it is the income which explains within the two approaches more than 87% of the energy end use.

Keywords

  • Energy load
  • occupant
  • dwelling modifications
  • simulations
  • Greenhouse Gas Emission
access type Open Access

Possibilities of the fish pass restoration

Published Online: 30 Mar 2018
Page range: 29 - 36

Abstract

Abstract

According to the new elaborated methodology of the Ministry of Environment of the Slovak Republic: Identification of the appropriate fish pass types according to water body typology (2015) each barrier on the river must be passable. On the barriers or structures without fish passes new ones should be design and built and on some water structures with existed but nonfunctional fish passes must be realized reconstruction or restoration of such objects. Assessment should be done in terms of the existing migratory fish fauna and hydraulic conditions. Fish fauna requirements resulting from the ichthyological research of the river section with barrier. Hydraulic conditions must than fulfil these requirements inside the fish pass body.

Keywords

  • fish pass
  • fish fauna requirements
  • hydraulic consideration
  • design parameters
access type Open Access

Synchronizing the city with human-based spaces

Published Online: 30 Mar 2018
Page range: 37 - 44

Abstract

Abstract

The paper is about to summarize the most important development tools to make the urban spaces more human friendly in Denver, Colorado. There are more needs for having more livable and sustainable areas by reducing the use of automobiles and focusing on multimodal street design. The strategies are the basic elements to make our urban spaces better and happier from The United States to Hungary

Keywords

  • America
  • new direction
  • urban design
  • public spaces
  • street life
  • communities
  • happiness
access type Open Access

Select geotechnical properties of a lime stabilized expansive soil amended with bagasse ash and coconut shell powder

Published Online: 30 Mar 2018
Page range: 45 - 60

Abstract

Abstract

Lime stabilization has been and still is one of the most preferred methods for stabilization of expansive soils. However, in the recent times, utilization of solid waste materials in soil stabilization has gained prominence as an effective means to manage wastes generated from various sources. In this work, an attempt has been made to utilize waste materials from two sources as auxiliary additives to lime in the stabilization of an expansive soil. Bagasse ash (BA), a waste by-product from the sugar industry and Coconut shell powder (CSP), a processed waste obtained from left over coconut shells of oil extraction industry were used as auxiliary additives. An expansive soil obtained from a local field was subjected to chemical, mineral, microstructural and geotechnical characterization in the laboratory and stabilized using 3% lime. The waste materials were subjected to chemical, mineral and microstructural characterization. The stabilization process was amended with four different contents viz. 0.25%, 0.5%, 1% and 2% of BA and CSP separately and the effect of the amendment was studied on the unconfined compressive strength (UCS), plasticity, swell-shrink and microstructural characteristics of the expansive soil. The results of the study indicated that BA amendment of lime stabilization performed better than CSP in improving the UCS, plasticity, swell-shrink and microstructure of the lime stabilized expansive soil.

Keywords

  • Lime Stabilization
  • Bagasse Ash
  • Coconut Shell Powder
  • Plasticity
  • Swell-Shrink
  • UCS
access type Open Access

Improved image processing of road pavement defect by infrared thermography

Published Online: 30 Mar 2018
Page range: 61 - 72

Abstract

Abstract

This paper intends to achieve improved image processing for the clear identification of defects in damaged road pavement structure using infrared thermography non-destructive testing (NDT). To that goal, 4 types of pavement specimen including internal defects were fabricated to exploit the results obtained by heating the specimens by natural light. The results showed that defects located down to a depth of 3 cm could be detected by infrared thermography NDT using the improved image processing method.

Keywords

  • infrared thermography
  • heat source from natural light
  • image processing
  • defect
  • asphalt
access type Open Access

Effects of corn cob ash on lime stabilized lateritic soil

Published Online: 30 Mar 2018
Page range: 73 - 85

Abstract

Abstract

This study assesses the effects of Corn Cob Ash (CCA) on lime-stabilized lateritic soil. Preliminary tests were carried out on the natural soil sample for purpose of identification and classification. Lime being the main stabilizing material was thoroughly mixed with the soil sample to determine the optimum lime requirement of the sample as a basis for evaluating the effects of the CCA. The optimum lime requirement was 10%. The CCA was thereafter added to the lime stabilized soil in varying proportions of 2, 4, 6, 8 and 10%. Unsoaked CBR increased from 83% at 0% CCA to highest value of 94% at 4% CCA. Unconfined Compressive Strength (UCS) values increased from 1123kN/m2 at 0% CCA to highest value of 1180kN/m2 at 4% CCA. It was therefore concluded that CCA can serve as a good complement for lime stabilization in lateritic soil.

Keywords

  • atterberg limit
  • corn cob ash
  • lateritic soil
  • lime stabilization
  • strength tests
access type Open Access

Numerical simulation of mechanical properties tests of tungsten mud waste geopolymer

Published Online: 30 Mar 2018
Page range: 87 - 94

Abstract

Abstract

Geopolymers are believed to become in the future an environmental friendly alternative for the concrete. The low CO2 emission during the production process and the possibility of ecological management of the industrial wastes are mentioned as main advantages of geopolymers. The main drawback, causing problems with application of geopolymers as a building material is the lack of the theoretical material model. Indicated problem is being solved now by the group of scientists from the Silesian University of Technology. The series of laboratory tests are carried out within the European research project REMINE. The paper introduces the numerical analyses of tungsten mud waste geopolymer samples which have been performed in the Atena software on the basis of the laboratory tests. Numerical models of bended and compressed samples of different shapes are presented in the paper. The results obtained in Atena software were compared with results obtained in Abaqus and Mafem3D software.

Keywords

  • geopolymers
  • material model
  • Atena software
  • tungsten mine waste
access type Open Access

Bond behavior of self compacting concrete

Published Online: 30 Mar 2018
Page range: 95 - 105

Abstract

Abstract

The success of an optimum design lies in the effective load transfer done by the bond forces at the steel-concrete interface. Self Compacting Concrete, is a new innovative concrete capable of filling intrinsic reinforcement and gets compacted by itself, without the need of external mechanical vibration. For this reason, it is replacing the conventional vibrated concrete in the construction industry. The present paper outlays the materials and methods adopted for attaining the self compacting concrete and describes about the bond behavior of this concrete. The bond stress-slip curve is similar in the bottom bars for both SCC and normal concrete whereas a higher bond stress and stiffness is experienced in the top and middle bars, for SCC compared to normal concrete. Also the interfacial properties revealed that the elastic modulus and micro-strength of interfacial transition zone [ITZ] were better on the both top and bottom side of horizontal steel bar in the SCC mixes than in normal vibrated concrete. The local bond strength of top bars for SCC is about 20% less than that for NC. For the bottom bars, however, the results were almost the same.

Keywords

  • Self Compacting concrete
  • Bond force
  • Transfer of stress
access type Open Access

Comparison of calculation and simulation of evacuation in real buildings

Published Online: 30 Mar 2018
Page range: 107 - 114

Abstract

Abstract

Each building must meet requirements for safe evacuation in order to prevent casualties. Therefore methods for evaluation of evacuation are used when designing buildings. In the paper, calculation methods were tested on three real buildings. The testing used methods of evacuation time calculation pursuant to Slovak standards and evacuation time calculation using the buildingExodus simulation software. If calculation methods have been suitably selected taking into account the nature of evacuation and at the same time if correct values of parameters were entered, we will be able to obtain almost identical times of evacuation in comparison with real results obtained from simulation. The difference can range from 1% to 27%.

Keywords

  • evacuation of building
  • evacuation time
  • calculation methods
  • input values
  • simulation
access type Open Access

Hydro power plants, an overview of the current types and technology

Published Online: 30 Mar 2018
Page range: 115 - 126

Abstract

Abstract

Despite the long history of hydropower technology and rising number of system harvesting energy from alternative sources, the constant research within hydro power sector becoming increasingly important as the power from water was and still is the leading alternative source of green energy generation, capitalized not necessarily within micro-urban structures only. The advantages of hydro systems involve their relatively low acquisition cost against durability, the possibility of gaining energy independence, relatively high flexibility and adaptability for spatial conditions and energy demands of the end users. Nowadays micro hydro systems could capitalize head range starting at 100cm and the efficiency of hydro systems in general ranges between 65-75% in micro and small applications climbing up to 96% in macro designs. It is mostly due to flexibility in applications, adaptability in combinations with other renewable energy systems and the ability to generate clean, stable, thus reliable energy that makes technical development the most vibrant and noticeable in the micro sphere.

Keywords

  • hydro power
  • power plant
  • renewable resources
  • water
access type Open Access

Comparison of physical and mechanical properties of river sand concrete with quarry dust concrete

Published Online: 30 Mar 2018
Page range: 127 - 134

Abstract

Abstract

This study compared the physical and mechanical properties of river sand concrete with quarry dust concrete. The constituent materials were batched by weight. The water-cement ratio and mix ratio selected for the experimental investigation were 0.55 and 1:2:4, respectively. The specimens were cured for 7, 14, 21 and 28 days. Slump, density and compressive strength tests were carried out. The results showed that river sand concrete had greater density and compressive strength than quarry dust concrete for all curing ages. At 28 days of curing, river sand concrete exceeded the target compressive strength by 36%, whereas quarry dust concrete was less than the target compressive strength by 12%. Both river sand concrete and quarry dust concrete for the selected water/cement ratio and mix ratio are suitable for non-structural applications and lightly-loaded members where high strength is not a prerequisite.

Keywords

  • density
  • compressive strength
  • concrete
  • river sand
  • quarry dust
access type Open Access

A practical approach to tramway track condition monitoring: vertical track defects detection and identification using time-frequency processing technique

Published Online: 30 Mar 2018
Page range: 135 - 146

Abstract

Abstract

This paper presents an automatic method for detecting vertical track irregularities on tramway operation using acceleration measurements on trams. For monitoring of tramway tracks, an unconventional measurement setup is developed, which records the data of 3-axes wireless accelerometers mounted on wheel discs. Accelerations are processed to obtain the vertical track irregularities to determine whether the track needs to be repaired. The automatic detection algorithm is based on time–frequency distribution analysis and determines the defect locations. Admissible limits (thresholds) are given for detecting moderate and severe defects using statistical analysis. The method was validated on frequented tram lines in Budapest and accurately detected severe defects with a hit rate of 100%, with no false alarms. The methodology is also sensitive to moderate and small rail surface defects at the low operational speed.

Keywords

  • tramway track condition monitoring
  • time-frequency signal processing
  • vibration
  • wheel-rail interaction
  • wavelet transform

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