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The disposal of waste from coal plants and waste glass (WG) is causing significant environmental problems all around the planet. Currently, the amount of discarding of these wastes is increased. One possible option is to utilize fly ash (FA) from coal plants as a partial substitute for the cement and EG as a fractional substitute for sand in concrete, respectively. Besides, fibers can improve the strength and durability of concrete; explicitly speaking, using coconut fibers (CFs) is in trend due to their highest toughness among natural fibers making it suitable material as fiber reinforcement in concrete. This research studies the concrete behavior with 15% FA as a partial substitute of cement with 2% CFs and waste beverage glass as sand at various replacement levels (14%, 15%, 16%, 17%, 18%, 19%, and 20%). Mechanical and durability characteristics of concrete were assessed, such as compression strength, water absorption, flexural strength, density, workability, and water absorption. The current study results show that adding FA, CFs, and WG improved microstructure quality at 16% replacement of sand. The study showed that the M4 mix has enhanced the properties of concrete samples as compressive and flexural strength was improved to 47.2 and 6.2 MPa and improved apparent density by 20%. Adding more WGP than the optimal proportion (16%) led to detrimental effects on void ratio, permeability, and water absorption. Therefore, 16% of sand with WG and 15% of FA with cement can be substituted with 2% CFs to develop sustainable concrete.

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The current coronavirus COVID-19 pandemic is impacting countries across the world, resulting in governments undertaking a number of precautionary measures for their populations. This raises the issue of the effectiveness of urban design of dwellings to assist with these measures. This study therefore determines the current readiness of local neighborhoods and housing in Saudi Arabia to face epidemics. The study employs an analysis of a public survey achieving a comprehensive (n = 413) across the country to identify: (a) the current situation of local neighborhood and services, including density and the ability to fulfil human needs during periods of quarantine; (b) the ability of housing design to assist with social distancing: (c) appropriate housing design to fulfil social needs; and (d) the design of housing to accommodate the ability for infected household members to self-isolate. The findings identify that neighborhoods in Saudi Arabia meet current social requirements and can assist in avoiding gatherings. In addition, it illustrates the advantages and disadvantages of housing design, revealing that villas tend to be low density, and so facilitate social distancing, but neighborhoods with a high number of residential units face considerable challenges, due to the high density of population, particularly in areas lacking planning.