cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.12094674.v1
title: Evaluation of coal ash use as an adhesion improver in asphalt mixtures

description: ABSTRACT The presence of moisture in asphalt mixtures interferes in the adhesion between the asphalt binder and the aggregates, as well as interferes into the asphalt binder film itself causing cohesive failure. This work evaluated the use of coal ashes as a bonding improver in asphalt mixtures, comparing this material with hydrated lime and stone powder. A total of 36 ash samples were collected at the UTE Energia Pecém/São Gonçalo do Amarante-CE, and a chemical characterization was performed using the X-ray fluorescence. It was found that about 68% of the ashes belong to class C, the remainder of the ashes being framed in class F. In the evaluation of the moisture damage resistance, through the Lottman test, it was verified that the use of 4 % of ash in the asphalt mixtures generated results similar to those found for the asphalt mixture containing natural filler. The use of the ashes combined with lime led to an increase in resistance to moisture damage. It is emphasized that the fact that some ashes belong to class C or F, or even that some ashes are more alkaline than others, did not necessarily lead to significant gains in the moisture damage resistance.
DOI: 10.6084/m9.figshare.12094686
title: Soil characterization for adobe mixtures containing Portland cement as stabilizer

description: ABSTRACT One of the most economical ways to build with soil is to use adobe technique. There are several types of soils and most of them are not suitable for using to construct buildings. Physical and chemical characteristics of the soils will influence on its performance to use for buildings. This work aims to characterize physically, chemically and mineralogically two soil samples and study the dosage of mixtures for adobe using Portland cement as stabilizer. It was studied three different Portland cement content (6%, 9% and 12%) in the soil. The results showed that compressive strength of up to 5 MPa at 28 days for both type of soils studied with 12% of Portland cement. In addition, a comparison between two methods used for the particle size analysis of the soils. It was observed that the results differed in each method analysis. Overall this work has shown that to use these soils for adobe bricks, 9% of Portland cement is enough to reach the minimum compressive strength required by standard. Furthermore, this research brings results about the determination of the clay content of the soil, indicating that the traditional method to determine the size distribution curve by sieving and sedimentation may not be the most suitable to check this clay content.
DOI: 10.6084/m9.figshare.12094686.v1
title: Soil characterization for adobe mixtures containing Portland cement as stabilizer

description: ABSTRACT One of the most economical ways to build with soil is to use adobe technique. There are several types of soils and most of them are not suitable for using to construct buildings. Physical and chemical characteristics of the soils will influence on its performance to use for buildings. This work aims to characterize physically, chemically and mineralogically two soil samples and study the dosage of mixtures for adobe using Portland cement as stabilizer. It was studied three different Portland cement content (6%, 9% and 12%) in the soil. The results showed that compressive strength of up to 5 MPa at 28 days for both type of soils studied with 12% of Portland cement. In addition, a comparison between two methods used for the particle size analysis of the soils. It was observed that the results differed in each method analysis. Overall this work has shown that to use these soils for adobe bricks, 9% of Portland cement is enough to reach the minimum compressive strength required by standard. Furthermore, this research brings results about the determination of the clay content of the soil, indicating that the traditional method to determine the size distribution curve by sieving and sedimentation may not be the most suitable to check this clay content.
DOI: 10.6084/m9.figshare.12094671
title: Effect of gypsum and granite residues on products from the red ceramic industry: Literature review

description: ABSTRACT The red ceramics industry comprises materials used in construction (bricks, tiles, expanded clay, among others) and is of great importance for Brazilian economic development, so the demand for its products has grown, causing a problem of scarcity of reserves of good quality raw materials and in economically appropriate places. Other materials also used in construction, such as granite (main product of the ornamental stone industry) and gypsum coating have shown growth in their demand, generating large amounts of waste, causing negative impact on the environment. The recycling of waste is increasingly evident due to the large volume generated by the sector. The red ceramic industry, due to its heterogeneous character, has been prominent in the incorporation of waste, as much to present advantages as the greater rigor of the current laws. The purpose of this work is to present an overview of the effects of the use of industrial waste, gypsum and granite, in the red ceramic industry, and also presents results of work carried out in this area. The results point to a scarce amount of research in the area of waste recycling of gypsum and granite, and that their use in ceramic mass complies with current legislation and also contributes to the reduction of negative impacts caused to the environment due to its disposal in undue places.
DOI: 10.6084/m9.figshare.12094671.v1
title: Effect of gypsum and granite residues on products from the red ceramic industry: Literature review

description: ABSTRACT The red ceramics industry comprises materials used in construction (bricks, tiles, expanded clay, among others) and is of great importance for Brazilian economic development, so the demand for its products has grown, causing a problem of scarcity of reserves of good quality raw materials and in economically appropriate places. Other materials also used in construction, such as granite (main product of the ornamental stone industry) and gypsum coating have shown growth in their demand, generating large amounts of waste, causing negative impact on the environment. The recycling of waste is increasingly evident due to the large volume generated by the sector. The red ceramic industry, due to its heterogeneous character, has been prominent in the incorporation of waste, as much to present advantages as the greater rigor of the current laws. The purpose of this work is to present an overview of the effects of the use of industrial waste, gypsum and granite, in the red ceramic industry, and also presents results of work carried out in this area. The results point to a scarce amount of research in the area of waste recycling of gypsum and granite, and that their use in ceramic mass complies with current legislation and also contributes to the reduction of negative impacts caused to the environment due to its disposal in undue places.
DOI: 10.6084/m9.figshare.12094704
title: Characterization of pottery kilns ash for application on pozzolanic cement

description: ABSTRACT The characterization of materials with potential for cement replacement it is an important mitigation of environmental impacts caused by the construction industry. Pozzolanic materials can improve the properties of concretes in the hardened state. However, in order for these properties to be active in the materials, they must meet the requirements, in Brazil, regulated by ABNT NBR 12653, presenting specific physical, chemical and mineralogical characteristics. Pottery kiln ash is the main solid residue produced by the industries producing red ceramics. Presidente Epitácio city, SP, has these industries as a highlight in its economy. This work performed tests of fluorescence and X-ray diffraction for chemical and mineralogical characterization. For physical characterization, laser granulometry and standardized tests were performed by ABNT NBR 5751 and 5752 . Mortars with 10%, 20% and 30% of the mass of cement replaced by ash were also tested for compression, cured for 7, 28 and 91 days. The results of tests performed showed a material that does not meet all the standardized demands, having positive results only in the particle size and index of pozzolanic activity with Portland cement, by ABNT NBR 5752. The results of the tests suggest the necessity of new tests for thermal activation of the material and, also to allow it is incorporation into the production of composite cements with potential use in pastes, mortars and concretes.
DOI: 10.6084/m9.figshare.12094704.v1
title: Characterization of pottery kilns ash for application on pozzolanic cement

description: ABSTRACT The characterization of materials with potential for cement replacement it is an important mitigation of environmental impacts caused by the construction industry. Pozzolanic materials can improve the properties of concretes in the hardened state. However, in order for these properties to be active in the materials, they must meet the requirements, in Brazil, regulated by ABNT NBR 12653, presenting specific physical, chemical and mineralogical characteristics. Pottery kiln ash is the main solid residue produced by the industries producing red ceramics. Presidente Epitácio city, SP, has these industries as a highlight in its economy. This work performed tests of fluorescence and X-ray diffraction for chemical and mineralogical characterization. For physical characterization, laser granulometry and standardized tests were performed by ABNT NBR 5751 and 5752 . Mortars with 10%, 20% and 30% of the mass of cement replaced by ash were also tested for compression, cured for 7, 28 and 91 days. The results of tests performed showed a material that does not meet all the standardized demands, having positive results only in the particle size and index of pozzolanic activity with Portland cement, by ABNT NBR 5752. The results of the tests suggest the necessity of new tests for thermal activation of the material and, also to allow it is incorporation into the production of composite cements with potential use in pastes, mortars and concretes.
DOI: 10.6084/m9.figshare.12094659.v1
title: Influence of thermal shock by brush cooling of concrete in fire situations

description: ABSTRACT In situations of abrupt temperature differences, as the residential fires, these structures must support the thermal chock. Thus, this is paper aims to assess the behavior of concrete exposed to high temperatures and subsequent abrupt cooling. For this we analyzed this effect on the characteristic resistences with fck of 25, 35 and 40MPa. The analyzies observed the resistence losses and the colorations of the concretes. The samples were submitted to the temperature of 300, 600, 900 and 1200°C for 90 minutes and tempered in freshwater. The strength were compared to the reference samples and to the theory to estimate the strength of the concrete exposed to abrupt cooling. The results show that concretes with Fck equal to 35 and 40MPa present lower strength when compared to the concrete with fck equal to 25MPa. On the other hand, at 900 and 1200°C, the percentage of strength lost is the same as 25MPa. However, at temperatures of 900 and 1200°C, the loss percentage is equal to the concrete with fck of 25MPa. That is, the higher the strength is, the higher the lost rate and the higher the incidence appearance of craks when heated and cooled.
DOI: 10.6084/m9.figshare.12094659
title: Influence of thermal shock by brush cooling of concrete in fire situations

description: ABSTRACT In situations of abrupt temperature differences, as the residential fires, these structures must support the thermal chock. Thus, this is paper aims to assess the behavior of concrete exposed to high temperatures and subsequent abrupt cooling. For this we analyzed this effect on the characteristic resistences with fck of 25, 35 and 40MPa. The analyzies observed the resistence losses and the colorations of the concretes. The samples were submitted to the temperature of 300, 600, 900 and 1200°C for 90 minutes and tempered in freshwater. The strength were compared to the reference samples and to the theory to estimate the strength of the concrete exposed to abrupt cooling. The results show that concretes with Fck equal to 35 and 40MPa present lower strength when compared to the concrete with fck equal to 25MPa. On the other hand, at 900 and 1200°C, the percentage of strength lost is the same as 25MPa. However, at temperatures of 900 and 1200°C, the loss percentage is equal to the concrete with fck of 25MPa. That is, the higher the strength is, the higher the lost rate and the higher the incidence appearance of craks when heated and cooled.
DOI: 10.6084/m9.figshare.12094710
title: Evaluation of the application of bottom ashes from thermoelectric in concrete blocks for pavements

description: ABSTRACT Considering the great generation of bottom ashes coming from a thermoelectric plant, it was decided to verify the incorporation of the same in the concrete used in interlocking blocks for paving. After the collection of conventional (cement and natural aggregates) and alternative (bottom ashes) materials, environmental tests (leached and solubilized extract) were performed on the ashes and physical characterization tests (particle size analysis, real density, liquidity and plasticity limits and hygroscopic humidity) in all aggregates. By means of granulometric stabilizations, two alternative traces with ash and one reference with conventional aggregates were prepared. In all concretes, the slump value was determined in the fresh state and, in the hardened state, compressive strength and water absorption tests were performed. Pavers type I (rectangular shape) with dimensions of 10 cm ÷ 20 cm ÷ 6 cm (width ÷ length ÷ thickness) were molded and tested for compressive strength. An empirical method was also used to design an interlocking pavement designed with the mixtures investigated. It can be seen that, in the water absorption test, the three traces studied presented average results below the maximum value of 6%, which is in accordance with the regulations. With respect to the compressive strength tests, the results are lower than the minimum of 35 MPa, however it is possible to target the pavers to areas of lower traffic demand, such as bike paths. It is concluded that the results obtained, from the experimental program, demonstrate that the use of bottom ashes on interlocking concrete pavements presents potential to be exploited for commercialization purposes.
DOI: 10.6084/m9.figshare.12094710.v1
title: Evaluation of the application of bottom ashes from thermoelectric in concrete blocks for pavements

description: ABSTRACT Considering the great generation of bottom ashes coming from a thermoelectric plant, it was decided to verify the incorporation of the same in the concrete used in interlocking blocks for paving. After the collection of conventional (cement and natural aggregates) and alternative (bottom ashes) materials, environmental tests (leached and solubilized extract) were performed on the ashes and physical characterization tests (particle size analysis, real density, liquidity and plasticity limits and hygroscopic humidity) in all aggregates. By means of granulometric stabilizations, two alternative traces with ash and one reference with conventional aggregates were prepared. In all concretes, the slump value was determined in the fresh state and, in the hardened state, compressive strength and water absorption tests were performed. Pavers type I (rectangular shape) with dimensions of 10 cm ÷ 20 cm ÷ 6 cm (width ÷ length ÷ thickness) were molded and tested for compressive strength. An empirical method was also used to design an interlocking pavement designed with the mixtures investigated. It can be seen that, in the water absorption test, the three traces studied presented average results below the maximum value of 6%, which is in accordance with the regulations. With respect to the compressive strength tests, the results are lower than the minimum of 35 MPa, however it is possible to target the pavers to areas of lower traffic demand, such as bike paths. It is concluded that the results obtained, from the experimental program, demonstrate that the use of bottom ashes on interlocking concrete pavements presents potential to be exploited for commercialization purposes.
DOI: 10.6084/m9.figshare.14320874
title: Predicting prolonged apnea during nurse-administered procedural sedation using machine learning

description: Participant characteristics, sedation dosing and respiratory states derived from capnography monitoring
DOI: 10.6084/m9.figshare.14320874.v3
title: Predicting prolonged apnea during nurse-administered procedural sedation using machine learning

description: Participant characteristics, sedation dosing and respiratory states derived from capnography monitoring
DOI: 10.6084/m9.figshare.14320874.v2
title: capnopred

description: Participant characteristics, sedation dosing and respiratory states derived from capnography monitoring
DOI: 10.6084/m9.figshare.12094665
title: Behavior of supersulfated cement (SSC) obtained from blast furnace slag generated by charcoal and coke and submitted to thermal curing

description: ABSTRACT The use of blast furnace slag (BFS) as a raw material in Portland cement (PC) has been considered for decades to reduce CO2 emissions and the exploitation of limestone and clay reserves involved in clinker production. Recently, interest in free or low clinker cements has grown, such as supersulfated cements (SSC), which are composed mostly of blast furnace slag, up to 90%. The chemical characteristics required for slag for use in SSC, however, are not the same as those required for use in PC. One of the most important characteristics of the slag is the ratio of the CaO and SiO2 content. Slags generated in charcoal kilns have a low CaO/SiO2 ratio and are considered acidic and those generated in coal kilns are considered basic. This study aims to evaluate the behavior of SSC obtained from two slag, A and B, generated in kilns with charcoal and mineral. Thermal curing was also used to improve the hydration kinetics and mechanical properties. The results showed that, although both slags met the standard limits of (EN 15743), the B was more suitable for use in SSC. Using thermal cure at 40 °C, it was possible to increase the formation of calcium silicate hydrate (CSH) and consequently the mechanical resistance of the SSC made with slag A. The lower calcium content of slag A was the probable cause of its low reactivity.
DOI: 10.6084/m9.figshare.12094665.v1
title: Behavior of supersulfated cement (SSC) obtained from blast furnace slag generated by charcoal and coke and submitted to thermal curing

description: ABSTRACT The use of blast furnace slag (BFS) as a raw material in Portland cement (PC) has been considered for decades to reduce CO2 emissions and the exploitation of limestone and clay reserves involved in clinker production. Recently, interest in free or low clinker cements has grown, such as supersulfated cements (SSC), which are composed mostly of blast furnace slag, up to 90%. The chemical characteristics required for slag for use in SSC, however, are not the same as those required for use in PC. One of the most important characteristics of the slag is the ratio of the CaO and SiO2 content. Slags generated in charcoal kilns have a low CaO/SiO2 ratio and are considered acidic and those generated in coal kilns are considered basic. This study aims to evaluate the behavior of SSC obtained from two slag, A and B, generated in kilns with charcoal and mineral. Thermal curing was also used to improve the hydration kinetics and mechanical properties. The results showed that, although both slags met the standard limits of (EN 15743), the B was more suitable for use in SSC. Using thermal cure at 40 °C, it was possible to increase the formation of calcium silicate hydrate (CSH) and consequently the mechanical resistance of the SSC made with slag A. The lower calcium content of slag A was the probable cause of its low reactivity.
DOI: 10.6084/m9.figshare.12094683
title: Concrete axial compressive strength with different loading directions and boundary conditions

description: ABSTRACT In this work the axial compression strength of 10 cm side cubic specimens of three concrete with characteristic strengths of 30 MPa, 50 MPa, and 65 MPa were analyzed experimentally. The compression load was applied in the same direction and perpendicular to the casting direction of the cubic specimens. The fracture mode was analyzed when the boundary conditions of the tests were modified. In the first boundary condition, grease was applied between the specimens and the machine’s plate to minimize friction. In the second boundary condition, 3 mm steel plates were glued to the sides of the specimens to maximize friction. One of the main results was that the strength change with the load direction. For the 50 MPa concrete, the compression strength was 16% higher when it was parallel to the casting direction than when it was perpendicular. With respect to the boundary conditions, it is found that when the specimen sides were restricted, there was an increase in the compression strength, independently of the concrete class. These results may be a potential contribution for the development of the reinforced concrete project and its structural analysis.
DOI: 10.6084/m9.figshare.12094683.v1
title: Concrete axial compressive strength with different loading directions and boundary conditions

description: ABSTRACT In this work the axial compression strength of 10 cm side cubic specimens of three concrete with characteristic strengths of 30 MPa, 50 MPa, and 65 MPa were analyzed experimentally. The compression load was applied in the same direction and perpendicular to the casting direction of the cubic specimens. The fracture mode was analyzed when the boundary conditions of the tests were modified. In the first boundary condition, grease was applied between the specimens and the machine’s plate to minimize friction. In the second boundary condition, 3 mm steel plates were glued to the sides of the specimens to maximize friction. One of the main results was that the strength change with the load direction. For the 50 MPa concrete, the compression strength was 16% higher when it was parallel to the casting direction than when it was perpendicular. With respect to the boundary conditions, it is found that when the specimen sides were restricted, there was an increase in the compression strength, independently of the concrete class. These results may be a potential contribution for the development of the reinforced concrete project and its structural analysis.
DOI: 10.6084/m9.figshare.12094716
title: Effect of Moisture Content on the Behavior of High Strength Concrete at High Temperatures

description: ABSTRACT In this paper, an experimental program was carried out to investigate the residual mechanical properties of high strength concrete and normal strength concrete, and how moisture content and temperature affect the spalling process. Three mixtures with water-cementitious material ratios, from 0.25 to 0.50, and with different saturation levels were heated in an electric furnace to elevated temperatures, from 200°C to 600°C. After heating, the specimens were cooled down to room temperature and then tested for compression and tensile strength. The results showed that high moisture content induces the spalling process and reduces considerably the mechanical properties of high strength concrete, mainly at temperatures above 400°C.