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The Volume Stability of Alkali-Activated Electric Arc Furnace Ladle Slag Mortar and Its Performance at High Temperatures. Processes (Basel) 2022. [DOI: 10.3390/pr10040700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
In this study, the engineering properties of Ordinary Portland Cement (OPC) and alkali-activated slag (AAS) mortar with electric arc furnace ladle slag (EAFLS) were investigated to reveal the effects of EAFLS on the expansion of cementitious mortars. Additionally, the effects of these two types of mortar were explored based on their compressive strength, especially at high temperatures. EAFLS in OPC mortars significantly reduced the compressive strength and caused serious soundness problems in the mortars after autoclaving due to the presence of free-CaO and free-MgO in the EAFLS slag. On the other hand, the AAS mortars produced with EAFLS had compressive strength comparable to ordinary OPC mortars and maintained soundness after autoclaving. During a 550 °C heat treatment, the OPC mortar cracked and lost residual strength, but the AAS mortar retained more than 90% of its residual strength. Even after an 800 °C heat treatment, the AAS mortar maintained 14% of its residual strength (about 4 MPa), sufficient to prevent the collapse of the specimen structure. The main reason is that alkali-activated technology can accelerate the hydration process and solve the delayed hydration problem. The results of this study indicated that EAFLS is suitable to partially replace the binder used in the production of AAS mortars, and the resulting AAS mortars have high volume stability, high compression strength, and good high temperature resistance.
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Toward Sustainable Healthcare Facilities: An Initiative for Development of “Mostadam-HCF” Rating System in Saudi Arabia. SUSTAINABILITY 2021. [DOI: 10.3390/su13126742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Saudi Arabia vision 2030 emphasizes the applications of sustainability concepts in all aspects of life in Saudi society. Accordingly, the Mostadam rating system for existing and new buildings was recently launched to achieve appropriate, sustainable building standards. In the medical field, sustainable healthcare facilities are an extension of the concept of sustainable buildings in terms of important sustainable healthcare parameters. Therefore, the sustainable development of healthcare facilities has great impacts on growing economic, social and environmental issues, which, in turn, improve Saudi society’s public health. Moreover, the COVID-19 pandemic has further exposed the urgent need for sustainable healthcare facilities to control the outbreak of such dangerous pandemics. Accordingly, the retrofitting of the existing healthcare facilities and the shift toward new sustainable ones have become an important objective of many countries worldwide. Currently, the concepts related to sustainable healthcare facilities are rapidly varying their scopes toward wider perspectives. Therefore, a new local rating system for healthcare facilities based on the potential and resources of sustainable healthcare facilities in Saudi Arabia should be developed. The present paper investigates the development of a new version of the Mostadam rating system, known here as “Mostadam-HCF”, in relation to the local Mostadam rating system and in accordance with the LEED version 4.1 (BD + C: Health-care). This important step can help the existing and the new healthcare facilities in Saudi Arabia to obtain, firstly, national accreditation and, consequently, to be internationally accredited. Moreover, the initiative of sustainable healthcare facilities can also help in fighting the current COVID-19 pandemic and the other possible future viruses in Saudi Arabia.
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