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The objective of this study was to analyze the physico-mechanical properties of gypsum boards including plastic waste aggregates from cable recycling. The plastic cable waste is incorporated into the gypsum matrix without going through any type of selection and/or treatment, as it is obtained after the cable recycling process. In the experimental process, gypsum boards of different dimensions were manufactured and tested for their Young’s modulus, shock-impact resistance, flexural strength, thermal conductivity, and thermal comfort. The results obtained show a significant increase in the elasticity of the boards with plastic waste (limited cracking), compliance with the minimum value of flexural strength, and a slight improvement in the thermal conductivity coefficient (lower energy demand) and surface comfort (reduced condensation and greater adherence). Therefore, the analyzed material could provide a suitable alternative to currently marketed gypsum boards, contributing to sustainable construction not only in new constructions, but also in building renovations.

Radiometric monitoring of construction materials is required for estimating the interior and exterior exposure to ionizing radiation emitted by terrestrial radioactive elements in building materials. Using gamma-ray spectroscopy, the activity concentrations of 226 Ra, 232 Th, and 40  K in fifty-two samples from eighteen different building materials commonly used in Erbil city, Kurdistan region, Iraq, were evaluated to assess possible radioactive dangers to human health. The activity concentrations of 226 Ra, 232 Th and 40  K ranged from 1 ± 0.1 (gypsum board) to 130 ± 11 (granite), 1.3 ± 0.2 (gypsum) to 66 ± 8 (ceramic sample), and 18.74 ± 4 (gypsum) to 1061.708 ± 40 (granite) with an average of 28 ± 5, 20.7 ± 4, and 340.8 ± 18 (average ± standard deviation), respectively. Radiological indicators (activity concentration index, alpha and gamma index, hazard indices, interior absorbed gamma dose rate and the corresponding yearly effective dosage rate, and excess lifetime cancer risk) were computed to assess the health risks associated with these building materials. Consideration was given to the indoor annual effective dosage for common construction materials, the radon surface expiration rate, and the indoor radon concentration. The mean values of activity concentration were then inputted into the RESRAD-BUILD computer software to calculate a resident’s long-term radiation exposure. The dosages were measured over a range of 0 to 70 years. From 0 to 30 years, there was a significant change in dosages; however, from 30 to 70 years, the dosages were reasonably consistent. This research demonstrates that granite samples are not safe for dwellings with poor ventilation (especially those without windows). In general, other investigated construction materials in the buildings are deemed safe for the population, since the computed values for these parameters fall within the well-being restrictions or criterion values.

Although gypsum-based building materials exhibit many positive characteristics, solutions are still being searched for to reduce the use of gypsum or improve the physico-mechanical properties of board materials. In this study, an attempt was made to produce gypsum boards with hemp fibers. Although hemp fibers can be a specific reinforcement for gypsum-based board materials, they negatively affect the gypsum setting process due to their hygroscopic characteristics. Fibers impregnated with derivatives based on polyvinyl acetate, styrene–acrylic copolymer and pMDI (polymeric diphenylmethane diisocyanate) were used in this study. Gypsum–fiber boards produced with impregnated fibers showed approximately 30% higher mechanical properties as determined by the 3-point bending test. The positive effect of the impregnates on the hemp fibers was confirmed by FTIR (Fourier-transform infrared spectroscopy) and TG/DTA (thermogravimetric analysis/thermal gravimetric analysis) analysis.

This research work focuses on the recycling of gypsum, a key component of drywall panels commonly used in construction. It proposes this practice as a technically and economically viable strategy that also aligns with the circular economy model. In this context, waste loses its status as refuse and is transformed back into raw material. A technical feasibility analysis was conducted based on a sample extracted from a specific project, which was subjected to characterization tests and mechanical behavior assessments in both laboratory and real construction conditions. Additionally, an economic feasibility analysis was performed by comparing the budgets of the same project in two scenarios: the traditional plastering process and the use of recycled gypsum. This analysis highlighted the fiscal and legal benefits that adopting the circular model could offer to stakeholders in the construction industry. This study began with a market analysis to determine the availability of recyclable material and to assess the multiple benefits that its reuse can provide. Based on the characterization of the material obtained from the construction site and the mechanical tests conducted, the economic advantages were evaluated for contractors as well as for the potential establishment of companies focused on gypsum recycling. All of this analysis was framed within the context of sustainability, emphasizing the positive environmental impacts of this practice, as well as the development of a strategy that serves as a valuable proposal for the construction sector. This work concludes that recycling gypsum in construction projects represents a technically, environmentally, and economically sustainable alternative that can positively transform the industry.

The modern construction industry is looking for new ecological materials (available, cheap, recyclable) that can successfully replace materials that are not environmentally friendly. Fibers of natural origin are materials that can improve the properties of gypsum composites. This is an important issue because synthetic fibers (hardly biodegradable—glass or polypropylene fibers) are commonly used to reinforce gypsum boards. Increasing the state of knowledge regarding the possibility of replacing synthetic fibers with natural fibers is another step towards creating more environmentally friendly building materials and determining their characteristics. This paper investigates the possibility of manufacturing fiber–gypsum composites based on natural gypsum (building gypsum) and hemp (Cannabis sativa L.) fibers grown in Poland. The effect of introducing hemp fibers of different lengths and with varying proportions of mass (mass of gypsum to mass of fibers) into the gypsum matrix was investigated. The experimental data obtained indicate that adding hemp fibers to the gypsum matrix increases the static bending strength of the composites manufactured. The highest mechanical strength, at 4.19 N/mm2, was observed in fiber–gypsum composites with 4% hemp fiber content at 50 mm in length. A similar trend of increased strength was observed in longitudinal tension. Again, the composite variant with 4% fiber content within the gypsum matrix had the highest mechanical strength. Manufacturing fibers–gypsum composites with more than 4% hemp fiber content negatively affected the composites’ strength. Mixing long (50 mm) hemp fibers with the gypsum matrix is technologically problematic, but tests have shown a positive effect on the mechanical properties of the refined composites. The article indicates the length and quantity limitations of hemp fibers on the basis of which fiber–gypsum composites were produced.

Gypsum board is a building material known for its various qualities and functional characteristics, including its low density, fire resistance, thermal insulation, moisture regulation, and decorative appeal. However, it is important to consider the environmental aspects, as the production of one ton of gypsum board releases approximately 355 kg of CO2 into the atmosphere. This research aims to reduce the carbon footprint while improving the mechanical and thermal properties of gypsum boards. To achieve this objective, flax fibers of three different lengths (12 mm, 24 mm, and 36 mm) were used to replace gypsum at a certain volume fraction. Incorporating up to 10% flax fiber effectively offsets the carbon footprint of gypsum boards. However, practical constraints related to the processing conditions and mechanical strength limited the addition of flax fiber to levels of 1%, 2%, and 3%. A 3% fiber incorporation gave us a more homogeneous mix with good workability, ensuring good mechanical performance and a 29% reduction in the carbon footprint. This study showed an improvement in flexural strength for flax-fiber-reinforced composites regardless of their length. In particular, the addition of 3% flax fiber (36 mm in length) showed the most significant increase in flexural strength, exceeding 438%. In addition, the mechanical behavior, including toughness, showed improvements over unreinforced gypsum. Flax fibers were found to be effective in bridging microcracks and limiting their propagation. Notably, all reinforced composites showed a decrease in thermal conductivity, resulting in a 47% improvement in thermal insulation with the addition of flax fibers.

Through exploring the effects of low pH on the composite system of desulfurization gypsum (DG) enhanced by melamine-formaldehyde resin (MF), it is found that the inducing of sulfate-ion, in contrast to chloride and oxalate ions, favors the longitudinal growth of the crystalline form of the hydration product, which was relatively simple and had the highest length to width ( L / D ) ratio. At the same time, MF can also improve L / D ratio of gypsum hydration products, which favors the formation of hydrated whiskers. Finally, in a composite system composed of hemihydrate gypsum, MF, and glass fibers, when dilute sulfuric acid was used to regulate pH=3–4, the tight binding formed among the components of the composite system compared to pH=5–6. The hydration product of gypsum adheres tightly to glass fiber surface and produces a good cross-linking and binding effect with MF. The flexural strength, compressive strength, elastic modulus, and water absorption of the desulphurized gypsum composite board is 22.7 MPa, 39.8 MPa, 5 608 MPa, and 1.8%, respectively.

This study looks at wall partition panels with hollow core wood elements and gypsum board as protection in fire conditions. In addition to our previous research, this study on wall partitions considers the effect of steel screws in the assembly of the elements, as well as the filling of the cavity with insulating material. The goal of this work is to calculate the fire resistance time and compare the results using different numerical models. The discussion of the results analyzes the effect of steel screws and the introduction of insulating material inside the cavities. The steel screws are verified with and without threads. The numerical models are based on the finite element method, using thermal and transient analysis with nonlinear materials. The thermal insulation criterion for measuring fire resistance is referenced by the EN 1363-1:2020 standard. The steel screws allow more heat to be concentrated and, therefore, distribute it throughout the wooden wall partition members. Based on the results obtained, the use of steel screws reduces fire resistance by 71.75 min, regardless of whether the wall partition is filled with or without insulating material.

Building envelopes have a critical role in the sustainability of the construction sector. The goals of the current research are assessing the environmental impacts of typical exterior wall assemblies and presenting the best Iranian market option through taking account of both embodied and operational energy. Autodesk Green Building Studio (GBS) is used to determine the operating loads of each wall. Simapro, a life cycle assessment software, is applied for managing data on environmental impacts. The derived results demonstrate that human health is the most severe damage category for all the analyzed walls. Also, the end-of-life stage’s environmental impact is insignificant compared to the production and use stages. Reducing carbon emissions has the highest priority, such that replacing 1 m 2 of masonry brick wall (the worst option) with prefabricated extruded polystyrene (XPS) drywall (the best option) can result in saving 1257.85 kgCO 2 eq. The operational phase of the studied walls has a wide range of environmental impacts. Prefabricated Knauf drywall as well as prefabricated XPS drywall consumes less energy for the operating phase mainly due to providing sufficient quantity of isolations that leads to the better total environmental performance. In conclusion, it should be noted that the thermal performance of building materials should be given more attention.

The energy consumption in buildings is high currently, leading to the development of the building envelope with phase change material (PCM), while the application of PCMs to the building envelope has the potential to effectively regulate the temperature variations in the inner surfaces of walls. Eutectic PCM consists of lauric acid, myristic acid, and stearic acid (LA-MA-SA) and was synthesized first, while expanded graphite (EG) and diamote (DE) were used as additives. LA-MA-SA/10 wt.% EG/10 wt.% DE composite PCM was synthesized via the impregnation method; then, the phase change layer was compressed and formed under a pressure of 10 MPa. The sandwich phase change gypsum board was built with three layers, considering the phase change layer on the outside, middle and indoor sides of the board, respectively. The thermal responses of sandwich phase change gypsum boards were considered under various radiation conditions at controlled temperatures of 37 °C, 40 °C, 45 °C and 50 °C. The results indicated that the gypsum board with the addition of 16.7 wt.% composite PCMs showed a better relative time duration of thermal comfort in comparison with pure gypsum board. The indoor heating rate slowed down, and the environmental temperature fluctuation was within a smaller range, because of the latent heat of the phase change gypsum board. Comparing the phase change gypsum boards at different interlayer positions, we found that the phase change gypsum board with an interlayer on the indoor side shows better thermal performance and a relatively longer time duration of thermal comfort, e.g., when the setting temperatures were 37 °C, 40 °C, 45 °C and 50 °C, respectively, the relative time durations of the thermal comfort of the sandwich phase change gypsum board were 4825 s, 3160 s, 1980 s and 1710 s. This study provides insights into the thermoregulation performance of phase change walls, where the utilization of a PCM in a wall can increase thermal capacity and enhance the inner-zone thermal comfort. The findings can provide guidelines for phase change walls to ensure sustainable practices in the energy savings of buildings.