Zoltan Orban - Academia.edu (original) (raw)

Papers by Zoltan Orban

Research paper thumbnail of Evaluation of the Loss of Uniaxial Compressive Strength of Sandstones Due to Moisture

The reduction in uniaxial compressive strength (UCS) was investigated for sandstones under variou... more The reduction in uniaxial compressive strength (UCS) was investigated for sandstones under various moisture levels. Thirty-four UK Darney sandstone samples were tested under six different moisture conditions. The time-dependent moisture gain and loss were also evaluated. For 77 sandstones identified in the literature, the loss of UCS between oven-dry and saturated conditions was up to 45%, with an average of 20%. For Darney stone, the average loss of UCS was around 20%, with UCS around 72 N/mm 2 when oven-dry and 58 N/mm 2 when fully saturated. During saturation, significant loss of UCS occurred soon after exposure to water with 80% of UCS being lost within the first 2.5-6 hours. For Darney stone 50% of UCS was lost at air-dry conditions. Results from the 78 sandstone types were compared with the equivalent compressive strength defined by BS EN 772-1:2011 for oven-dry, air-dry, and saturated conditions. The estimated values by BS EN 772-1:2011 for dry and saturated UCS agreed well with the available test data and indicated a lower-bound solution. For immersed conditions, BS EN 772-1:2011, however, overestimates the reduction in UCS for a large number of samples and provides an average, instead of a lower-bound solution.

Research paper thumbnail of Számítási modellek és diagnosztikai eljárások fejlesztése műemlék jellegű, falazott hídszerkezetek teherbírásának megállapítására és használhatósági …

… OTKA Research Reports, 2009

A tégla és kőanyagú boltozott hidak igen jelentős részét képezik a hídállománynak hazánkban és vi... more A tégla és kőanyagú boltozott hidak igen jelentős részét képezik a hídállománynak hazánkban és világszerte. A boltozatos hidak a hídállomány legrégebbi szerkezetei, terhelési körülményeik az építésük óta eltelt időszakban drasztikus változásokon mentek ...

Research paper thumbnail of Zerstoerungsfreie Pruefung von Mauerwerk-Bogenbruecken - Eine Uebersicht

Der Beitrag gibt einen Ueberblick zu den in Ungarn bei der Pruefung von Eisenbahnbruecken beziehu... more Der Beitrag gibt einen Ueberblick zu den in Ungarn bei der Pruefung von Eisenbahnbruecken beziehungsweise Eisenbahnunterfuehrungen, die als Bogenbruecken aus Mauerwerk ausgefuehrt wurden, angewendeten Methoden mit Schwerpunkt bei den zerstoerungsfreien Pruefverfahren. Zugrunde liegt dieser Arbeit ein von der Ungarischen Eisenbahn initiiertes Testprogramm zur Ausarbeitung von Inspektionsmethoden fuer Mauerwerkskonstruktionen in Rahmen eines internationalen Forschungsprojekts. Gegenstand der Untersuchungen waren folgende Pruefverfahren: Georadar, Infrarotthermographie und seismische Methoden sowie ergaenzend und zur Kalibrierung und Verifizierung Befahren von Bohrloechern mit Kameras. Die Georadaruntersuchungen erfolgten an vorgefertigten Mauerwerkselementen mit 1,35 m Laengen- und Breitenabmessungen, die mit Hohlraeumen und anderen fuer Mauerwerk typischen Ausfuehrungsmaengeln versehen waren. An diesen Probeelementen wurde auch der Einfluss verschiedener Fugenfuellmaterialien und der...

Research paper thumbnail of Optimal Thickness of Roof Insulation for Residential Building in a Hot and Arid Climate

SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings

Research paper thumbnail of The effect of recycled tyre steel fibers on the properties of concrete

Pollack Periodica, 2021

Steel fibers recovered from recycled tires were considered for use as reinforcement in concrete t... more Steel fibers recovered from recycled tires were considered for use as reinforcement in concrete to improve the tensile properties of concrete as well as being an economically viable and environmentally friendly alternative. This paper investigates the effect of purified and non-purified recycled tire steel fiber in concrete with a constant fiber proportion of 30 kg m−3 to determine properties in fresh and hardened concrete. The results indicate that concrete with purified tire fibers have better tensile properties than those with non-purified tire fibers. Density, strength, and toughness significantly increase but workability tends to decrease when using recycled tire steel fiber as reinforcement in concrete.

Research paper thumbnail of Nationwide, Operational Sentinel-1 Based InSAR Monitoring System in the Cloud for Strategic Water Facilities in Hungary

Remote Sensing

The intensive development of both interferometric technology and sensors in recent years allows I... more The intensive development of both interferometric technology and sensors in recent years allows Interferometric Synthetic Aperture Radar (InSAR)-based applications to be accessible to a growing number of users. InSAR-based services now cover entire countries and soon even the whole of Europe. These InSAR systems require massive amounts of computer processing power and significant time to generate a final product. Most, if not all, of these projects have a limited “monitoring component”, aimed at historical analysis but are rarely, if ever, updated. Consequently, the results do not necessarily meet every purpose or specific user requirement. It is now clear that the increasing computing capacity and big data provided by the sensors have initiated the development of new InSAR services. However, these systems are only useful when linked to specific real-world operational problems. Continuous monitoring of a country’s ageing water management infrastructure has become an increasingly cri...

Research paper thumbnail of Codes: Modified parameter-setting-free harmony search (PSFHS) algorithm for optimizing the design of reinforced concrete beams

Python 3.7 and Matlab codes for the modified PSFHS algorithm proposed. Those files are placed to ... more Python 3.7 and Matlab codes for the modified PSFHS algorithm proposed. Those files are placed to reproduce the results, replication of results, of the benchmark function presented in the research paper (Appendix B). The files presented here are not perfect in the programmatic sense. The authors focused on the readability of the files more than the efficiency of the presented codes. The complete source code is not provided in this context; they could be subjected to commercial copyrights in the near future. For any question about the presented work please contact the first author, Email: <em><strong>mahmoud.shaqfa@epfl.ch</strong>.</em>

Research paper thumbnail of Controlling the failure behavior of FRP-reinforced concrete elements

Pollack Periodica, 2021

Concrete indeterminate flexural members represented by continuous beams reinforced with both fibe... more Concrete indeterminate flexural members represented by continuous beams reinforced with both fiber-reinforced polymers and steel bars in a way that allows for moment redistribution at failure are analyzed. The efficiency of introducing steel bars in the critical sections where plastic hinges are likely to form is evaluated in terms of reliability. Monte Carlo simulation and the concept of comparative reliability are both employed. Ultimately, the effect of different design parameters on the strength reduction factor is evaluated.

Research paper thumbnail of Temporary strengthening of steel brigde element with FRP sheet

Pollack Periodica, 2014

The paper presents a case study that summarizes the monitoring results of a steel bridge strength... more The paper presents a case study that summarizes the monitoring results of a steel bridge strengthening project where a damaged structural element was temporary strengthened with fiber reinforced plastic sheet. The evolution of damage and the effects of strengthening were monitored with a computerized 24-channel displacement measuring system during normal traffic operation. The results of the monitoring project confirmed the efficiency of the proposed strengthening solution by comparing displacement results prior and after the strengthening intervention, and highlighted the need for applying a system that is capable to follow fatigue damage evolution.

Research paper thumbnail of Discrete element analysis of a stone masonry arch

Mechanics Research Communications, 2009

The aim of this study was to investigate the effect of the backfill on the mechanical behavior of... more The aim of this study was to investigate the effect of the backfill on the mechanical behavior of a multi-span masonry arch with the help of the discrete element method. After defining the geometry and identifying the mechanical properties of a one-span bridge model according to real experimental results from the literature, we extended the one-span model to a multi-span model and replaced the original backfill material with different sands and clays for investigations under live load in service loading conditions. We compared the deflections, the normal stresses in the arch and the plasticity state of the backfill under the live load. Then we also made load tests in different load cases to specify the effect of the stiffness, friction angle and cohesion of the backfill on load-bearing capacity. We found that the stiffness, the friction angle and the cohesion of the backfill largely influenced the load-bearing capacity of the structure.

Research paper thumbnail of Assessment of masonry arch railway bridges using non-destructive in-situ testing methods

Engineering Structures, 2009

The paper presents methods of inspection and testing for masonry arch railway bridges. An overvie... more The paper presents methods of inspection and testing for masonry arch railway bridges. An overview of a selection of available non-destructive, minor-destructive and monitoring methods is given and their efficacy for the assessment of masonry arch bridges is discussed. The principles of in-situ load tests are described and a methodology for the assessment of masonry arch railway bridges is shown through case studies. Results of a testing programme are demonstrated where the efficiency of various non-destructive testing methods has been studied. It is shown that non-destructive investigation and non-destructive insitu load-testing can provide valuable information on the condition of bridges and help verify basic input parameters for structural analysis and assessment.

Research paper thumbnail of Non-Destructive Testing of masonry arch bridges - an overview

Bautechnik, 2008

... The entire surface of the arch and the side walls is 400 cm ¥ 520 cm. Examples of the recorde... more ... The entire surface of the arch and the side walls is 400 cm ¥ 520 cm. Examples of the recorded radargrams are shown in Fig. ... More loose material was found behind the stone layer of the abutment front walls. Gra-vels behind the internal arch barrel are well embedded in mortar. ...

Research paper thumbnail of Assessment and lifetime expectancy of historical masonry arch bridges

Pollack Periodica, 2014

ABSTRACT

Research paper thumbnail of A Sensitivity Analysis for Thermal Performance of Building Envelope Design Parameters

Sustainability

Sensitivity analysis is crucial in building energy assessments. It is used to determine the major... more Sensitivity analysis is crucial in building energy assessments. It is used to determine the major variables influencing building thermal performance, using both observational research and energy simulation models. This study investigates the most influential envelope design parameters on the thermal performance of a typical residential building in Budapest, Hungary. Sensitivity analysis is used in conjunction with the IDA-Indoor and Climate Energy (IDA-ICE 4.8) simulation tool to assess the effects of 33 envelope design parameters for energy consumption and carbon dioxide concentrations. The input parameters include thickness, materials, density, specific heat and thermal conductivity of the basement, exterior floor, interior floor, exterior wall, interior wall, roof, ground slab, glazing type, and infiltration rate. The results show that exterior floor materials have the biggest impact on annual delivered energy for heating and cooling, whereas the density of all structural element...

Research paper thumbnail of Sustainable design of concrete using industrial additives and wastes

Pollack Periodica, 2021

Concrete is the most widely used construction material in the world. Over ten billion tons of con... more Concrete is the most widely used construction material in the world. Over ten billion tons of concrete are being produced each year resulting in exhaustion of natural materials and an enormous carbon footprint. One of the primary goals of concrete technology today is to reduce the use of Portland cement and natural fine aggregates by partially replacing them with various waste materials and by-products of industrial processes. The paper summarizes the results of a study where the partial replacement of river sand and Portland cement was successfully applied using steel slag aggregate, silica fume and glass waste.

Research paper thumbnail of Integration of InSAR Technology in the Stability Assessment of Load Bearing Structures

Vestnik IzhGTU imeni M.T. Kalashnikova, 2021

Неразрушающий контроль зданий и сооружений является актуальной проблемой в современном строительс... more Неразрушающий контроль зданий и сооружений является актуальной проблемой в современном строительстве. Несмотря на то, что за последние десятилетия было разработано много измерительных методов, все же остаются некоторые пробелы в системе оценки состояния зданий и сооружений. Одна из основных проблем заключается в том, что измеряемые параметры оцениваются лишь время от времени. Существует ограниченное количество доступных методов, которые могут обеспечить непрерывный мониторинг технического состояния строительных сооружений и предоставить информацию об их устойчивости во временном ряду. Основная цель данной статьи - представить диагностический метод, который может преодолеть упомянутые недостатки, сочетая периодические неразрушающие измерения с непрерывным мониторингом, получаемым путем применения спутникового дистанционного зондирования. Радар с синтезированной апертурой (SAR) имеет много преимуществ, которые стоит учитывать инженерам-строителям в практике оценки устойчивости зданий ...

Research paper thumbnail of Experimental Study on the Performance of Frp Tendon Anchoring Devices in Axial Tension

The paper presents an experimental research on anchoring devices developed for the pre-tensioning... more The paper presents an experimental research on anchoring devices developed for the pre-tensioning of fiber reinforced polymer tendons in the stress range between 40 and 70% of tensile strength. The technique of testing, the criteria of assessing the load capacity and the influence of preloading applied on the anchor wedges on the initial tendons slippage are described. The optimal technical configurations of the anchoring device have been obtained, including parameters regarding the necessary prior anchorage of the tendon ends based on the strength properties of the tendon bar and the requirements to avoid slippage during the tensile tests.

Research paper thumbnail of Compressive strength of solid clay brickwork of masonry bridges: Estimate through Schmidt Hammer tests

Construction and Building Materials

Research paper thumbnail of New simple method for the assessment of masonry arch bridges

Pollack Periodica, 2016

The paper presents an approximation method for the assessment of the load carrying capacity of ma... more The paper presents an approximation method for the assessment of the load carrying capacity of masonry arch railway bridges. The method is a simple semi-empirical tool for the initial level assessment that is considered to serve as a first sieve and provides conservative values for the load-carrying capacity and permissible axle load of single-span arches. The proposed method is based on results obtained by the RING 2.0 masonry arch bridge analysis software. The method uses a closed mathematical formula to calculate the carrying capacity and its input parameters can easily be determined by simple site inspections or using data from bridge files.

Research paper thumbnail of Increasing the reliability of the assessment of masonry arch bridges by non-destructive testing

Pollack Periodica

The paper presents methods of inspection of masonry arch railway bridges. Results of a test progr... more The paper presents methods of inspection of masonry arch railway bridges. Results of a test program are demonstrated where the efficiency of various non-destructive testing methods for the inspection of arches was studied. It is shown that non-destructive investigation can provide valuable information regarding the condition of the bridge and help establishing basic input parameters for structural analysis and condition assessment.

Research paper thumbnail of Evaluation of the Loss of Uniaxial Compressive Strength of Sandstones Due to Moisture

The reduction in uniaxial compressive strength (UCS) was investigated for sandstones under variou... more The reduction in uniaxial compressive strength (UCS) was investigated for sandstones under various moisture levels. Thirty-four UK Darney sandstone samples were tested under six different moisture conditions. The time-dependent moisture gain and loss were also evaluated. For 77 sandstones identified in the literature, the loss of UCS between oven-dry and saturated conditions was up to 45%, with an average of 20%. For Darney stone, the average loss of UCS was around 20%, with UCS around 72 N/mm 2 when oven-dry and 58 N/mm 2 when fully saturated. During saturation, significant loss of UCS occurred soon after exposure to water with 80% of UCS being lost within the first 2.5-6 hours. For Darney stone 50% of UCS was lost at air-dry conditions. Results from the 78 sandstone types were compared with the equivalent compressive strength defined by BS EN 772-1:2011 for oven-dry, air-dry, and saturated conditions. The estimated values by BS EN 772-1:2011 for dry and saturated UCS agreed well with the available test data and indicated a lower-bound solution. For immersed conditions, BS EN 772-1:2011, however, overestimates the reduction in UCS for a large number of samples and provides an average, instead of a lower-bound solution.

Research paper thumbnail of Számítási modellek és diagnosztikai eljárások fejlesztése műemlék jellegű, falazott hídszerkezetek teherbírásának megállapítására és használhatósági …

… OTKA Research Reports, 2009

A tégla és kőanyagú boltozott hidak igen jelentős részét képezik a hídállománynak hazánkban és vi... more A tégla és kőanyagú boltozott hidak igen jelentős részét képezik a hídállománynak hazánkban és világszerte. A boltozatos hidak a hídállomány legrégebbi szerkezetei, terhelési körülményeik az építésük óta eltelt időszakban drasztikus változásokon mentek ...

Research paper thumbnail of Zerstoerungsfreie Pruefung von Mauerwerk-Bogenbruecken - Eine Uebersicht

Der Beitrag gibt einen Ueberblick zu den in Ungarn bei der Pruefung von Eisenbahnbruecken beziehu... more Der Beitrag gibt einen Ueberblick zu den in Ungarn bei der Pruefung von Eisenbahnbruecken beziehungsweise Eisenbahnunterfuehrungen, die als Bogenbruecken aus Mauerwerk ausgefuehrt wurden, angewendeten Methoden mit Schwerpunkt bei den zerstoerungsfreien Pruefverfahren. Zugrunde liegt dieser Arbeit ein von der Ungarischen Eisenbahn initiiertes Testprogramm zur Ausarbeitung von Inspektionsmethoden fuer Mauerwerkskonstruktionen in Rahmen eines internationalen Forschungsprojekts. Gegenstand der Untersuchungen waren folgende Pruefverfahren: Georadar, Infrarotthermographie und seismische Methoden sowie ergaenzend und zur Kalibrierung und Verifizierung Befahren von Bohrloechern mit Kameras. Die Georadaruntersuchungen erfolgten an vorgefertigten Mauerwerkselementen mit 1,35 m Laengen- und Breitenabmessungen, die mit Hohlraeumen und anderen fuer Mauerwerk typischen Ausfuehrungsmaengeln versehen waren. An diesen Probeelementen wurde auch der Einfluss verschiedener Fugenfuellmaterialien und der...

Research paper thumbnail of Optimal Thickness of Roof Insulation for Residential Building in a Hot and Arid Climate

SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings

Research paper thumbnail of The effect of recycled tyre steel fibers on the properties of concrete

Pollack Periodica, 2021

Steel fibers recovered from recycled tires were considered for use as reinforcement in concrete t... more Steel fibers recovered from recycled tires were considered for use as reinforcement in concrete to improve the tensile properties of concrete as well as being an economically viable and environmentally friendly alternative. This paper investigates the effect of purified and non-purified recycled tire steel fiber in concrete with a constant fiber proportion of 30 kg m−3 to determine properties in fresh and hardened concrete. The results indicate that concrete with purified tire fibers have better tensile properties than those with non-purified tire fibers. Density, strength, and toughness significantly increase but workability tends to decrease when using recycled tire steel fiber as reinforcement in concrete.

Research paper thumbnail of Nationwide, Operational Sentinel-1 Based InSAR Monitoring System in the Cloud for Strategic Water Facilities in Hungary

Remote Sensing

The intensive development of both interferometric technology and sensors in recent years allows I... more The intensive development of both interferometric technology and sensors in recent years allows Interferometric Synthetic Aperture Radar (InSAR)-based applications to be accessible to a growing number of users. InSAR-based services now cover entire countries and soon even the whole of Europe. These InSAR systems require massive amounts of computer processing power and significant time to generate a final product. Most, if not all, of these projects have a limited “monitoring component”, aimed at historical analysis but are rarely, if ever, updated. Consequently, the results do not necessarily meet every purpose or specific user requirement. It is now clear that the increasing computing capacity and big data provided by the sensors have initiated the development of new InSAR services. However, these systems are only useful when linked to specific real-world operational problems. Continuous monitoring of a country’s ageing water management infrastructure has become an increasingly cri...

Research paper thumbnail of Codes: Modified parameter-setting-free harmony search (PSFHS) algorithm for optimizing the design of reinforced concrete beams

Python 3.7 and Matlab codes for the modified PSFHS algorithm proposed. Those files are placed to ... more Python 3.7 and Matlab codes for the modified PSFHS algorithm proposed. Those files are placed to reproduce the results, replication of results, of the benchmark function presented in the research paper (Appendix B). The files presented here are not perfect in the programmatic sense. The authors focused on the readability of the files more than the efficiency of the presented codes. The complete source code is not provided in this context; they could be subjected to commercial copyrights in the near future. For any question about the presented work please contact the first author, Email: <em><strong>mahmoud.shaqfa@epfl.ch</strong>.</em>

Research paper thumbnail of Controlling the failure behavior of FRP-reinforced concrete elements

Pollack Periodica, 2021

Concrete indeterminate flexural members represented by continuous beams reinforced with both fibe... more Concrete indeterminate flexural members represented by continuous beams reinforced with both fiber-reinforced polymers and steel bars in a way that allows for moment redistribution at failure are analyzed. The efficiency of introducing steel bars in the critical sections where plastic hinges are likely to form is evaluated in terms of reliability. Monte Carlo simulation and the concept of comparative reliability are both employed. Ultimately, the effect of different design parameters on the strength reduction factor is evaluated.

Research paper thumbnail of Temporary strengthening of steel brigde element with FRP sheet

Pollack Periodica, 2014

The paper presents a case study that summarizes the monitoring results of a steel bridge strength... more The paper presents a case study that summarizes the monitoring results of a steel bridge strengthening project where a damaged structural element was temporary strengthened with fiber reinforced plastic sheet. The evolution of damage and the effects of strengthening were monitored with a computerized 24-channel displacement measuring system during normal traffic operation. The results of the monitoring project confirmed the efficiency of the proposed strengthening solution by comparing displacement results prior and after the strengthening intervention, and highlighted the need for applying a system that is capable to follow fatigue damage evolution.

Research paper thumbnail of Discrete element analysis of a stone masonry arch

Mechanics Research Communications, 2009

The aim of this study was to investigate the effect of the backfill on the mechanical behavior of... more The aim of this study was to investigate the effect of the backfill on the mechanical behavior of a multi-span masonry arch with the help of the discrete element method. After defining the geometry and identifying the mechanical properties of a one-span bridge model according to real experimental results from the literature, we extended the one-span model to a multi-span model and replaced the original backfill material with different sands and clays for investigations under live load in service loading conditions. We compared the deflections, the normal stresses in the arch and the plasticity state of the backfill under the live load. Then we also made load tests in different load cases to specify the effect of the stiffness, friction angle and cohesion of the backfill on load-bearing capacity. We found that the stiffness, the friction angle and the cohesion of the backfill largely influenced the load-bearing capacity of the structure.

Research paper thumbnail of Assessment of masonry arch railway bridges using non-destructive in-situ testing methods

Engineering Structures, 2009

The paper presents methods of inspection and testing for masonry arch railway bridges. An overvie... more The paper presents methods of inspection and testing for masonry arch railway bridges. An overview of a selection of available non-destructive, minor-destructive and monitoring methods is given and their efficacy for the assessment of masonry arch bridges is discussed. The principles of in-situ load tests are described and a methodology for the assessment of masonry arch railway bridges is shown through case studies. Results of a testing programme are demonstrated where the efficiency of various non-destructive testing methods has been studied. It is shown that non-destructive investigation and non-destructive insitu load-testing can provide valuable information on the condition of bridges and help verify basic input parameters for structural analysis and assessment.

Research paper thumbnail of Non-Destructive Testing of masonry arch bridges - an overview

Bautechnik, 2008

... The entire surface of the arch and the side walls is 400 cm ¥ 520 cm. Examples of the recorde... more ... The entire surface of the arch and the side walls is 400 cm ¥ 520 cm. Examples of the recorded radargrams are shown in Fig. ... More loose material was found behind the stone layer of the abutment front walls. Gra-vels behind the internal arch barrel are well embedded in mortar. ...

Research paper thumbnail of Assessment and lifetime expectancy of historical masonry arch bridges

Pollack Periodica, 2014

ABSTRACT

Research paper thumbnail of A Sensitivity Analysis for Thermal Performance of Building Envelope Design Parameters

Sustainability

Sensitivity analysis is crucial in building energy assessments. It is used to determine the major... more Sensitivity analysis is crucial in building energy assessments. It is used to determine the major variables influencing building thermal performance, using both observational research and energy simulation models. This study investigates the most influential envelope design parameters on the thermal performance of a typical residential building in Budapest, Hungary. Sensitivity analysis is used in conjunction with the IDA-Indoor and Climate Energy (IDA-ICE 4.8) simulation tool to assess the effects of 33 envelope design parameters for energy consumption and carbon dioxide concentrations. The input parameters include thickness, materials, density, specific heat and thermal conductivity of the basement, exterior floor, interior floor, exterior wall, interior wall, roof, ground slab, glazing type, and infiltration rate. The results show that exterior floor materials have the biggest impact on annual delivered energy for heating and cooling, whereas the density of all structural element...

Research paper thumbnail of Sustainable design of concrete using industrial additives and wastes

Pollack Periodica, 2021

Concrete is the most widely used construction material in the world. Over ten billion tons of con... more Concrete is the most widely used construction material in the world. Over ten billion tons of concrete are being produced each year resulting in exhaustion of natural materials and an enormous carbon footprint. One of the primary goals of concrete technology today is to reduce the use of Portland cement and natural fine aggregates by partially replacing them with various waste materials and by-products of industrial processes. The paper summarizes the results of a study where the partial replacement of river sand and Portland cement was successfully applied using steel slag aggregate, silica fume and glass waste.

Research paper thumbnail of Integration of InSAR Technology in the Stability Assessment of Load Bearing Structures

Vestnik IzhGTU imeni M.T. Kalashnikova, 2021

Неразрушающий контроль зданий и сооружений является актуальной проблемой в современном строительс... more Неразрушающий контроль зданий и сооружений является актуальной проблемой в современном строительстве. Несмотря на то, что за последние десятилетия было разработано много измерительных методов, все же остаются некоторые пробелы в системе оценки состояния зданий и сооружений. Одна из основных проблем заключается в том, что измеряемые параметры оцениваются лишь время от времени. Существует ограниченное количество доступных методов, которые могут обеспечить непрерывный мониторинг технического состояния строительных сооружений и предоставить информацию об их устойчивости во временном ряду. Основная цель данной статьи - представить диагностический метод, который может преодолеть упомянутые недостатки, сочетая периодические неразрушающие измерения с непрерывным мониторингом, получаемым путем применения спутникового дистанционного зондирования. Радар с синтезированной апертурой (SAR) имеет много преимуществ, которые стоит учитывать инженерам-строителям в практике оценки устойчивости зданий ...

Research paper thumbnail of Experimental Study on the Performance of Frp Tendon Anchoring Devices in Axial Tension

The paper presents an experimental research on anchoring devices developed for the pre-tensioning... more The paper presents an experimental research on anchoring devices developed for the pre-tensioning of fiber reinforced polymer tendons in the stress range between 40 and 70% of tensile strength. The technique of testing, the criteria of assessing the load capacity and the influence of preloading applied on the anchor wedges on the initial tendons slippage are described. The optimal technical configurations of the anchoring device have been obtained, including parameters regarding the necessary prior anchorage of the tendon ends based on the strength properties of the tendon bar and the requirements to avoid slippage during the tensile tests.

Research paper thumbnail of Compressive strength of solid clay brickwork of masonry bridges: Estimate through Schmidt Hammer tests

Construction and Building Materials

Research paper thumbnail of New simple method for the assessment of masonry arch bridges

Pollack Periodica, 2016

The paper presents an approximation method for the assessment of the load carrying capacity of ma... more The paper presents an approximation method for the assessment of the load carrying capacity of masonry arch railway bridges. The method is a simple semi-empirical tool for the initial level assessment that is considered to serve as a first sieve and provides conservative values for the load-carrying capacity and permissible axle load of single-span arches. The proposed method is based on results obtained by the RING 2.0 masonry arch bridge analysis software. The method uses a closed mathematical formula to calculate the carrying capacity and its input parameters can easily be determined by simple site inspections or using data from bridge files.

Research paper thumbnail of Increasing the reliability of the assessment of masonry arch bridges by non-destructive testing

Pollack Periodica

The paper presents methods of inspection of masonry arch railway bridges. Results of a test progr... more The paper presents methods of inspection of masonry arch railway bridges. Results of a test program are demonstrated where the efficiency of various non-destructive testing methods for the inspection of arches was studied. It is shown that non-destructive investigation can provide valuable information regarding the condition of the bridge and help establishing basic input parameters for structural analysis and condition assessment.