The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
Rafael Travincas - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of in-service performance factors of renders based on In-Situ Testing techniques
Journal of Building Engineering, 2021Co-Authors: Dora Silveira, Ana Gonçalves, Inês Flores-colen, M. Rosário Veiga, Isabel Torres, Rafael TravincasAbstract:Abstract In order to contribute to the knowledge about the influence of several factors on the in-service performance of renders, as well as about the applicability of In-Situ Testing techniques in the evaluation of their performance, an experimental work was carried. In this work, the influence of some factors (type of substrate, number and thickness of mortar layers) on the mechanical and physical performance of two mortars (site-made and industrial) was evaluated, using the following In-Situ Testing techniques: pendulum rebound hammer test (with two types of rebound hammer), ultrasonic pulse velocity test (with two types of device) and water absorption under low pressure test (with Karsten tubes). It was possible to verify that the above-mentioned factors influence the performance of the mortars. The In-Situ Testing techniques were, in general, able to identify differences in the behaviour of renders due to these factors. However, for the same technique, different devices sometimes led to distinct results. Nevertheless, the combination of the results of different techniques helped to reduce the uncertainty of the analysis.
A. Hawreen - One of the best experts on this subject based on the ideXlab platform.
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Non-destructive mechanical and physical In-Situ Testing of rendered walls under natural exposure
Construction and Building Materials, 2020Co-Authors: J. Galvão, Inês Flores-colen, R. Duarte, J. De Brito, A. HawreenAbstract:Abstract Building facades are significantly influenced by the wall renders’ performance, since they are the first protection layer against degradation agents. During their service life, facades undergo a continuous performance reduction until they are unable to meet their demanded functions, such as protecting and waterproofing the facade. Therefore, the application of In-Situ Testing has great importance to evaluate in-service performance of wall renders under natural conditions. This study focuses on Testing the physical and mechanical behaviour of rendered facades, taking into account different render colourings and roughness and natural exposure conditions according to the wall orientation. Physical (Karsten tube and moisture meter) and mechanical In-Situ tests (pendulum rebound hammer and ultrasound pulse velocity) were performed on eight walls at a natural ageing station. The In-Situ tests were used to detect the factors affecting the results of these techniques, and the evolution of the rendered walls’ performance over time was investigated. The relationships between the Testing techniques were also assessed.
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variability of in situ Testing in wall coating systems karsten tube and moisture meter techniques
Journal of building engineering, 2020Co-Authors: R. Duarte, J. De Brito, I Florescolen, A. HawreenAbstract:Abstract To meet customers' demand and adequate levels of satisfaction, there are various reasons for the need of proactive maintenance and knowledge about in-service performance of building facades. From this perspective, performing inspections depends on the in-service appraisal's reliability and the presence of monitored and measured parameters along the life cycle under real exposure conditions. Water, the major in-service deterioration agent, has different origins and transport mechanisms through facades, including wind-driven rain, ground moisture, and wetting/drying of surfaces, resulting in various chemical and/or physical-pathological phenomena. Thus, water resistance is considered highly relevant due to its significant influence on the durability of coating systems. This study presents results of an investigation concerning the water resistance of in-service wall coating systems, focusing on conventional and industrial renders and adapting appropriate techniques for field analyses, namely Karsten tube and moisture meter. In-service parameters (water absorption under low pressure and surface moisture) are assessed, and the techniques' sensitivity is analysed considering exposure and inspection conditions, roughness, coating and finishing types, and existing anomalies. The capacity of these techniques to monitor in-service performance is also discussed, and in-service performance criteria are proposed.
Inês Flores-colen - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of in-service performance factors of renders based on In-Situ Testing techniques
Journal of Building Engineering, 2021Co-Authors: Dora Silveira, Ana Gonçalves, Inês Flores-colen, M. Rosário Veiga, Isabel Torres, Rafael TravincasAbstract:Abstract In order to contribute to the knowledge about the influence of several factors on the in-service performance of renders, as well as about the applicability of In-Situ Testing techniques in the evaluation of their performance, an experimental work was carried. In this work, the influence of some factors (type of substrate, number and thickness of mortar layers) on the mechanical and physical performance of two mortars (site-made and industrial) was evaluated, using the following In-Situ Testing techniques: pendulum rebound hammer test (with two types of rebound hammer), ultrasonic pulse velocity test (with two types of device) and water absorption under low pressure test (with Karsten tubes). It was possible to verify that the above-mentioned factors influence the performance of the mortars. The In-Situ Testing techniques were, in general, able to identify differences in the behaviour of renders due to these factors. However, for the same technique, different devices sometimes led to distinct results. Nevertheless, the combination of the results of different techniques helped to reduce the uncertainty of the analysis.
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Non-destructive mechanical and physical In-Situ Testing of rendered walls under natural exposure
Construction and Building Materials, 2020Co-Authors: J. Galvão, Inês Flores-colen, R. Duarte, J. De Brito, A. HawreenAbstract:Abstract Building facades are significantly influenced by the wall renders’ performance, since they are the first protection layer against degradation agents. During their service life, facades undergo a continuous performance reduction until they are unable to meet their demanded functions, such as protecting and waterproofing the facade. Therefore, the application of In-Situ Testing has great importance to evaluate in-service performance of wall renders under natural conditions. This study focuses on Testing the physical and mechanical behaviour of rendered facades, taking into account different render colourings and roughness and natural exposure conditions according to the wall orientation. Physical (Karsten tube and moisture meter) and mechanical In-Situ tests (pendulum rebound hammer and ultrasound pulse velocity) were performed on eight walls at a natural ageing station. The In-Situ tests were used to detect the factors affecting the results of these techniques, and the evolution of the rendered walls’ performance over time was investigated. The relationships between the Testing techniques were also assessed.
Dora Silveira - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of in-service performance factors of renders based on In-Situ Testing techniques
Journal of Building Engineering, 2021Co-Authors: Dora Silveira, Ana Gonçalves, Inês Flores-colen, M. Rosário Veiga, Isabel Torres, Rafael TravincasAbstract:Abstract In order to contribute to the knowledge about the influence of several factors on the in-service performance of renders, as well as about the applicability of In-Situ Testing techniques in the evaluation of their performance, an experimental work was carried. In this work, the influence of some factors (type of substrate, number and thickness of mortar layers) on the mechanical and physical performance of two mortars (site-made and industrial) was evaluated, using the following In-Situ Testing techniques: pendulum rebound hammer test (with two types of rebound hammer), ultrasonic pulse velocity test (with two types of device) and water absorption under low pressure test (with Karsten tubes). It was possible to verify that the above-mentioned factors influence the performance of the mortars. The In-Situ Testing techniques were, in general, able to identify differences in the behaviour of renders due to these factors. However, for the same technique, different devices sometimes led to distinct results. Nevertheless, the combination of the results of different techniques helped to reduce the uncertainty of the analysis.
Simon D. Goldsworthy - One of the best experts on this subject based on the ideXlab platform.
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Effects of an Electric Field on White Sharks: In Situ Testing of an Electric Deterrent
2016Co-Authors: Charlie Huveneers, Paul J. Rogers, Jayson M. Semmens, Crystal Beckmann, Alison A. Kock, Simon D. GoldsworthyAbstract:Elasmobranchs can detect minute electromagnetic fields,,1 nVcm–1, using their ampullae of Lorenzini. Behavioural responses to electric fields have been investigated in various species, sometimes with the aim to develop shark deterrents to improve human safety. The present study tested the effects of the Shark Shield Freedom7TM electric deterrent on (1) the behaviour of 18 white sharks (Carcharodon carcharias) near a static bait, and (2) the rates of attacks on a towed seal decoy. In the first experiment, 116 trials using a static bait were performed at the Neptune Islands, South Australia. The proportion of baits taken during static bait trials was not affected by the electric field. The electric field, however, increased the time it took them to consume the bait, the number of interactions per approach, and decreased the proportion of interactions within two metres of the field source. The effect of the electric field was not uniform across all sharks. In the second experiment, 189 tows using a seal decoy were conducted near Seal Island, South Africa. No breaches and only two surface interactions were observed during the tows when the electric field was activated, compared with 16 breaches and 27 surface interactions without the electric field. The present study suggests that the behavioural response of white sharks and the level of risk reduction resulting from the electric field is contextually specific, and depends on the motivational state o
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Effects of an Electric Field on White Sharks: In Situ Testing of an Electric Deterrent
PloS one, 2013Co-Authors: Charlie Huveneers, Paul J. Rogers, Jayson M. Semmens, Crystal Beckmann, Alison A. Kock, Brad Page, Simon D. GoldsworthyAbstract:Elasmobranchs can detect minute electromagnetic fields,
