Research

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17 pages, 5256 KiB

Open AccessArticle

Nonwoven Textile Waste Added with PCM for Building Applications

by Chiara Rubino, Stefania Liuzzi, Francesco Martellotta, Pietro Stefanizzi and Pierfrancesco Straziota

Appl. Sci. 2021, 11(3), 1262; https://doi.org/10.3390/app11031262 - 30 Jan 2021

Cited by 6 | Viewed by 2713

Abstract

Due to the overall improvement of living standards and considering the priority to reduce the energy consumption, the adoption of efficient strategies, mainly in the building area is mandatory. In fact, the construction sector can be considered as one of the key field [...] Read more.

Due to the overall improvement of living standards and considering the priority to reduce the energy consumption, the adoption of efficient strategies, mainly in the building area is mandatory. In fact, the construction sector can be considered as one of the key field essential for the sustainability, due to the diversity of components and their life cycles. Reuse strategies may play an essential role in reducing the environmental impact of building processes. Within this framework, the reuse of textile waste to produce insulating materials represents one of the biggest opportunities for the promotion of a circular economy. It contributes significantly to improve the environmental sustainability reusing a waste as new raw matter involved to achieve high energy efficient buildings. This paper provides the results of an experimental campaign performed using wool waste derived from the industrial disposal of fabrics matched with phase change materials (PCMs) used in order to enhance the thermal mass of the final products. Physical and thermal parameters were measured in order to demonstrate the good performances of the textile materials and the essential role played by PCMs in shifting heat waves and reduce surface temperatures. Furthermore, DesignBuilder software was used to assess the energy consumption of a mobile shelter type structure under three different climatic scenarios. A comparison between the experimented materials and other solutions, currently available in the market, highlighted a significant reduction in energy consumption when adopting the materials under test. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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19 pages, 3969 KiB

Open AccessArticle

Reliability Study of Equilibrium Moisture Content Methods for Sorption/Desorption Isotherms Determination of Autoclaved Aerated Concrete

by Richard Slávik, Alena Struhárová and Miroslav Čekon

Appl. Sci. 2021, 11(2), 824; https://doi.org/10.3390/app11020824 - 17 Jan 2021

Cited by 5 | Viewed by 2554

Abstract

Autoclaved aerated concrete (AAC) and its hygric parameters are a highly important issue in the field of building physics. There are several methods currently available to determine the equilibrium moisture content of building materials. Beside the conventional ones, new methods are constantly being [...] Read more.

Autoclaved aerated concrete (AAC) and its hygric parameters are a highly important issue in the field of building physics. There are several methods currently available to determine the equilibrium moisture content of building materials. Beside the conventional ones, new methods are constantly being introduced. This study explores the sorption/desorption properties of of three types of commercially produced AACs with three different bulk densities and demonstrates the application of the relevant methods available to characterize these parameters. The reliable characterization of the studied material was done through the conventional static approach, using the desiccator and an environmental chamber, and a new automated method of dynamic vapor sorption is implemented. The goal is to compare and identify the reliability of all methods used with respect to the efficiency of the data measurement process. Sound consistency between the results of the conventional methods and the experimental data obtained indicates the dynamic vapor sorption technique is highly reliable when measuring the equilibrium moisture content—particularly exemplified during the AAC sample testing. Therefore, the methodology developed in this study is expected to provide the reference for measuring the sorption/desorption isotherms of building materials with both static and automated techniques. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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22 pages, 3712 KiB

Open AccessFeature PaperArticle

Moisture Buffering in Surface Materials Due to Simultaneous Varying Relative Humidity and Temperatures: Experimental Validation of New Analytical Formulas

by Valeria Cascione, Carl-Eric Hagentoft, Daniel Maskell, Andy Shea and Pete Walker

Appl. Sci. 2020, 10(21), 7665; https://doi.org/10.3390/app10217665 - 29 Oct 2020

Cited by 4 | Viewed by 1734

Abstract

Buildings are subjected to the indoor environment, especially in non-controlled climates. Temperature and humidity variations might effect or even damage materials sensitive to moisture. For this reason, it is important to understand the response of hygroscopic materials to variable indoor environmental conditions. Existing [...] Read more.

Buildings are subjected to the indoor environment, especially in non-controlled climates. Temperature and humidity variations might effect or even damage materials sensitive to moisture. For this reason, it is important to understand the response of hygroscopic materials to variable indoor environmental conditions. Existing methods looked into the dynamic sorption capacity of materials, by analysing the impact of only humidity fluctuations, with temperature usually considered non-influential or non variable. However, temperature fluctuations may impact the moisture capacity of the materials, as materials properties might substantially vary with temperature. Moreover, in existing protocols, the humidity variations are considered to be varying under square wave fluctuations, which may not be applicable in environments, where the indoor is influenced by daily and seasonal climate variations, which presents more complex fluctuation. In this study, a simulation method that can predict the impact of environmental condition on materials under simultaneous temperature and humidity fluctuations was developed. Clay and gypsum plaster were analysed in the numerical model and results were then validated with experimental data. Materials were subjected to either sinusoidal and triangular temperature and RH variations and different cycle time intervals. The investigation of sinusoidal and triangular environmental variations pushed to a better understanding of materials response to different environments and to the improvement of the simplified model. The development of a simplified model can realistically predict the potential future impact of climate changes on buildings without the use of complex and memory demanding computational methods. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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12 pages, 4814 KiB

Open AccessFeature PaperArticle

Thermally Aerated Geopolymers as Lightweight Construction Material

by Antonio Licciulli, Ehsan Ul Haq, Muhammad Suhaib Ashraf, Khurram Rashid and Sanosh Kunjalukkal Padmanabhan

Appl. Sci. 2020, 10(19), 6697; https://doi.org/10.3390/app10196697 - 25 Sep 2020

Cited by 1 | Viewed by 1820

Abstract

In this research work, thermal foaming of bottom ash and sodium silicate geopolymer is proposed as a production process for light weight bricks. The composition and temperatures were studied and optimized to get the most suitable intumescence properties for the lightweight construction applications. [...] Read more.

In this research work, thermal foaming of bottom ash and sodium silicate geopolymer is proposed as a production process for light weight bricks. The composition and temperatures were studied and optimized to get the most suitable intumescence properties for the lightweight construction applications. For this purpose, four different compositions (i.e., 10%, 20%, 30%, and 40% bottom ash (BA)) were cured at four different curing temperatures (CT) (i.e., 200, 400, 500, and 600 °C). Sodium silicate (SS) to sodium hydroxide (SH) ratio was kept constant in order to keep the activation capacity of the solution constant in all the samples so that the effect of composition and CT could be studied effectively. All samples were characterized by bulk density, foamability, compression test, XRD, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), water absorption index (WAI), and weight loss index (WLI). These characterizations finally led to the optimized parameters to get the most appropriate intumescence properties. It was found that bottom ash and sodium silicate geopolymer foams have good potential to produce lightweight aerated blocks. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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13 pages, 2779 KiB

Open AccessArticle

New Flame Retardant Systems Based on Expanded Graphite for Rigid Polyurethane Foams

by Anna Strąkowska, Sylwia Członka, Piotr Konca and Krzysztof Strzelec

Appl. Sci. 2020, 10(17), 5817; https://doi.org/10.3390/app10175817 - 22 Aug 2020

Cited by 21 | Viewed by 2431

Abstract

The effect of the addition of new flame retardant systems on the properties of rigid polyurethane (RPUF) foams, in particular, reduction in flammability, was investigated. The modification included the introduction of a flame retardant system containing five parts by weight of expanded graphite [...] Read more.

The effect of the addition of new flame retardant systems on the properties of rigid polyurethane (RPUF) foams, in particular, reduction in flammability, was investigated. The modification included the introduction of a flame retardant system containing five parts by weight of expanded graphite (EG) (based on the total weight of polyol), one part by weight of pyrogenic silica (SiO₂) and an ionic liquid (IL): 1-ethyl-3-methylimidazolium tetrafluoroborate ([emim] [BF₄]), in an amount of 3:1 with respect to the weight of added silica. The kinetics of the synthesis of modified foams—including the growth rate and the maximum temperature—were determined and the physicochemical properties, such as the determination of apparent density and structure by optical microscopy, mechanical properties such as impact strength, compressive strength and, three-point bending test were determined. An important aspect was also to examine the thermal properties such as thermal stability or flammability. It has been shown that for rigid polyurethane foams, the addition of expanded graphite in the presence of silica and ionic liquid has a great influence on the general use properties. All composites were characterized by reduced flammability as well as better mechanical properties, which may contribute to a wider use of rigid polyurethane foams as construction materials. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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23 pages, 32668 KiB

Open AccessArticle

Energy Sustainability of Bio-Based Building Materials in the Cold and Severe Cold Regions of China—A Case Study of Residential Buildings

by Haibo Guo, Siyuan Zhou, Tongyu Qin, Lu Huang, Wenjie Song and Xunzhi Yin

Appl. Sci. 2020, 10(5), 1582; https://doi.org/10.3390/app10051582 - 26 Feb 2020

Cited by 7 | Viewed by 2835

Abstract

The aim of this research is to investigate the energy sustainability of cross-laminated timber (CLT) and straw residential buildings in the Cold and Severe Cold Regions of China. In the study, three building materials, namely reinforced concrete (RC), CLT, and straw bale, are [...] Read more.

The aim of this research is to investigate the energy sustainability of cross-laminated timber (CLT) and straw residential buildings in the Cold and Severe Cold Regions of China. In the study, three building materials, namely reinforced concrete (RC), CLT, and straw bale, are used separately to design the building envelope in reference residential buildings in different climate zones. The energy consumption during the operation phase of these buildings is then simulated using Integrated Environmental Solutions—Virtual Environment software (IES-VE). The results show that both CLT and straw buildings are more efficient than reinforced concrete with a reduction in energy consumption during the operational phase. Overall, the calculated heating energy-saving ratios for CLT buildings in Hailar, Harbin, Urumchi, Lanzhou, and Beijing are 3.04%, 7.39%, 7.43%, 12.69%, and 13.41%, respectively, when compared with RC. The calculated energy-saving ratios for heating in straw buildings in comparison with RC in these cities are 8.04%, 22.09%, 22.17%, 33.02%, and 34.28%, respectively. The results also reveal that a south orientation of the main building facade results in approximately 5% to 7% energy reduction in comparison with east or west orientations, and as the building height increases, energy consumption decreases gradually. Although RC is the most frequently used building material in Cold and Severe Cold regions in China, as bio-based building materials, there is great potential to promote CLT and straw bale construction in view of the energy sustainability features. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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13 pages, 2685 KiB

Open AccessArticle

CBR Predictive Models for Granular Bases Using Physical and Structural Properties

by Mildred Estivaly Montes-Arvizu, Omar Chavez-Alegria, Eduardo Rojas-Gonzalez, Jose Ramon Gaxiola-Camacho and Jesus Roberto Millan-Almaraz

Appl. Sci. 2020, 10(4), 1414; https://doi.org/10.3390/app10041414 - 20 Feb 2020

Cited by 4 | Viewed by 2944

Abstract

The California bearing ratio (CBR) test evaluates the structure of the layers of pavements. Such a test is laborious, time-consuming, and its results are generally affected by sample disturbance and tests conditions. The main objective of this research was to build a numerical [...] Read more.

The California bearing ratio (CBR) test evaluates the structure of the layers of pavements. Such a test is laborious, time-consuming, and its results are generally affected by sample disturbance and tests conditions. The main objective of this research was to build a numerical model for the prediction of CBR tests that might substitute laboratory tests. The model was based on structural and physical parameters of granular bases. Four different materials from the central region (Querétaro) and north (Mexicali) of Mexico were used for the experimental work. Using the above-mentioned materials, 36 samples were fabricated, and six of them were used for the evaluation of the model presented in this research. Numerical and experimental comparisons demonstrated the adequacy of the model to predict the result of CBR tests from soil parameters. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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15 pages, 2820 KiB

Open AccessArticle

Experimental Study on the Workability and Stability of Steel Slag Self-Compacting Concrete

by Suiwei Pan, Depeng Chen, Xiuling Chen, Genwang Ge, Danyang Su and Chunlin Liu

Appl. Sci. 2020, 10(4), 1291; https://doi.org/10.3390/app10041291 - 14 Feb 2020

Cited by 9 | Viewed by 3377

Abstract

There is important application value and economic value in exploring the potential use of steel slag to prepare self-compacting concrete (SCC) and make full use of solid waste resources. In this paper, steel slag self-compacting concrete (SSCC) with relatively ideal workability is prepared [...] Read more.

There is important application value and economic value in exploring the potential use of steel slag to prepare self-compacting concrete (SCC) and make full use of solid waste resources. In this paper, steel slag self-compacting concrete (SSCC) with relatively ideal workability is prepared by using steel slag instead of natural fine aggregate based on mix proportion optimization and SSCC performance research. The filling ability, passing ability and resistance segregation were tested to evaluate the workability of SSCC. The results show that when the content of steel slag sand is 20%, the workability performance of SSCC is similar to that of SCC with natural aggregates. When the content of steel slag sand is less than 60%, the performance of SSCC can also meet the workability requirements after adjusting the amount of raw materials. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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Review

Jump to: Research

21 pages, 4885 KiB

Open AccessReview

Durability Issues and Corrosion of Structural Materials and Systems in Farm Environment

by Chrysanthos Maraveas

Appl. Sci. 2020, 10(3), 990; https://doi.org/10.3390/app10030990 - 03 Feb 2020

Cited by 22 | Viewed by 5202

Abstract

This review paper investigated the durability and corrosion of materials used in the construction of agricultural buildings. Even though concrete and metal were the materials of choice in the construction of farm structures, they are susceptible to corrosion and environmental degradation. Acid attacks [...] Read more.

This review paper investigated the durability and corrosion of materials used in the construction of agricultural buildings. Even though concrete and metal were the materials of choice in the construction of farm structures, they are susceptible to corrosion and environmental degradation. Acid attacks result in the oxidation of metals and mass losses and reduced compressive strength of the metal structures. Concrete structures are degraded in high humidity environments, such as lagoons, agricultural effluents, and animal manure. Poultry, cow, and pig manure contain variable quantities of corrosion-inducing chemicals, such as sulfates, nitrates, chlorides, hydrogen sulfide, and ammonia. However, the degradation of concrete structures can be mitigated by the utilization of modified concrete containing sulfur, fly ash, silica fume, and nanoparticles such as silica. Concrete structures made of fiber-reinforced polymers are less prone to corrosion and are more durable. The design for durability has also emerged as a viable option for optimizing the service life of agricultural buildings by adhering to the exposure limits. Full article

(This article belongs to the Special Issue Building Materials from Fundamentals to Applications)

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