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Natural sand extraction for concrete manufacturing is a global issue for ecological balance and environmental concerns. This study introduced three mixes with three newly developed sand types to replace natural sand in concrete manufacturing. Additionally, three more mixes were made by incorporating optimized 10% silica fume. The durability of the prepared mixes was evaluated at high temperatures of (150–750 °C) at the interval of 150 °C and against immersion in a 5% sulfuric acid solution for 28, 56, 91, and 182 days, respectively. The study’s results reported the stability of the samples up to 300 °C, and then the fall of the samples started at 450 °C. Severe damage in the samples was formed at about 600 °C, and finally, a total collapse was seen at 750 °C. From (150 to 750 °C), the mix TYPE-3SSFC with a sustainable sand combination (50% recycled sand + 45% desert sand + 5% crumb rubber) and 10% silica fume showed better resistance than the other mixes. The compressive strength in the mix TYPE-3SSFC was 20.6%, 16.3%, 14.7%, 21.3%, 26.5%, and 43.2% higher than the mix TYPE-3SC with 10% silica fume. The mix TYPE-3SSFC with optimized 10% silica fume content showed better resistance against 5% sulfuric acid solution than those without silica fume. By morphological analysis, the mix TYPE-3SSFC showed that the interface improved due to the dense interconnectivity of the concrete mix between the crumb rubber paste and silica fume content. A dense calcite crystal was also seen in the mixture, which confirmed the study’s results. The mix with TYPE 2-Sand (100% recycled sand) revealed inferior results, low stability, and high damage. Thus, 100% recycled sand is not recommended for structural concrete.

For sustainable management of a threatened river, a process-based understanding as well as in-depth study of the river is required. Unfortunately, during Anthropocene almost every river in the world is under threat. Damodar river, an important drainage system of the Bhagirathi–Hooghly river basin situated in the eastern part of India is not an exception to this. Besides construction of dams and embankment, man has changed the nature of this river by unscientific overexploitation of riverine sand not only from the river bed but also fertile river bars and adjacent river terrace which leads to environmental disruption through adverse dramatic impacts on the river morphology, ecosystem, hydrology and environment. Though from an economic and flood management point of view, we have to mine this inexpensive resource from river, we should follow scientific methods in appropriate mining sites. For this purpose, study of river sensitivity based on active and total channel area can be a good strategy. In the case of Damodar river, using sensitivity we classified 12 reaches in very low, low, moderate and high sensitive sections and suggested section wise which method should be applied. We hope that this study will help to use rivers in a sustainable way.

Even to date, the excessive mining of natural river sand is an unattempted issue. It is a global problem that impacts the river's ecosystem and the environment. This study has attempted to develop a new technique to modify vacant desert sand to replace 100% natural river sand. A technique is introduced in this study to modify desert sand by adding manufactured and recycled sand separately. Four new concrete mixes were prepared with developed modified sand. Additional four mixes were obtained when 12.5% ordinary Portland cement was replaced with silica fume. A detailed compressive strength was evaluated on 8 prepared mixes at curing ages of 3, 7, 28, 56, 91, and 360 days. The physical properties, such as density, absorption, and porosity, were evaluated at 28 days. The sulphuric acid attack was also studied to evaluate durability at 28, 56, 91, and 120 days. The developed concrete mixes with 12.5% silica fume at all curing phases revealed higher compressive strength than those without. The developed sustainable modified sand with 12.5% silica fume filled the pores and absorbed less water than the samples without silica fume. The modified sand with 12.5% silica fume revealed better density, water absorption, and voids and showed better resistance against 5% sulphuric acid solution than those without silica fume. It is concluded that all newly developed mixes showed satisfactory results. Moreover, the mix of (50% desert sand + 50% recycled sand) and 12.5% silica fume is the best sustainable mix for replacing 100% river sand and 12.5% cement from the concrete industry. Highlights A novel methodology has been developed to utilize 50% desert sand in the concrete industry. This study recommends the amendment in ACI-211.1-91 using fine desert sand in concrete. The modified sand concrete that was developed passed the strength and durability criteria. The mix (50%RS + 50%DS2 + 12.5%SF) is the best sustainable concrete for this study.

During metal casting processes, large quantities of Spent Foundry Sand (SFS) are generated as waste, making its proper disposal a current research focus in industrial solid waste management. This study investigates the suitability of SFS by replacing natural river sand at equal mass ratios of 5%, 10%, 15%, and 20% to produce green concrete, with subsequent testing of compressive strength (CS), splitting tensile strength (STS), and chloride ion permeability. The results demonstrate that in terms of mechanical properties, at 28 days of curing, a 15% SFS substitution achieved maximum increases of 26% in CS and 12.87% in STS compared to control concrete. Regarding durability, the 28‐day SFS green concrete showed a 7.2% to 17.7% reduction in electrical flux relative to the control group. A recognized limitation is the use of SFS from a single source; future work should validate these findings with SFS from varied origins and include statistical robustness analysis. Furthermore, SEM/EDS analysis revealed that SFS primarily functions as a pore‐filling material without generating new hydration products. These findings indicate that using untreated SFS as a river sand substitute in concrete production reduces manufacturing costs and environmental pollution and enhances mechanical performance and durability. This “zero‐treatment” strategy provides a direct, scalable, and genuinely circular pathway for industrial waste valorization, demonstrating significant potential for large‐scale, sustainable concrete production. This study demonstrates the successful incorporation of Spent Foundry Sand (SFS) as a sustainable alternative to natural sand in concrete, enhancing compressive and tensile strengths by up to 26% and 12.87%, respectively, while reducing chloride permeability. The optimal 15% SFS substitution improves both mechanical performance and durability, supporting eco‐friendly construction practices.

The United Nations has declared a global sand crisis. The construction industry, as a major user of sand, needs to significantly reduce the use of this finite natural resource. The purpose of this study is to measure the level of awareness of the sand crisis among construction industry professionals, to assess their reactions upon learning of the crisis, and to determine sources of information for those who are aware of the crisis. The Cognitive-Affective-Conative model was applied as the theoretical framework. The study is based on a survey and in-depth interviews with 75 construction industry professionals in the United States and Canada. Analyses included level of awareness by professional role and by reaction, as well as level of awareness by role and by type of information. Results showed that knowledge of the sand crisis was generally low. A content analysis of interview transcripts categorized five reactions to the crisis. These results suggest that generally across all roles, those with more familiarity with the sand crisis had reactions of proactive and feel bad while those with less familiarity expressed curiosity and surprise. Denial was expressed by a few. Recommendations include: First, greater efforts are required to inform construction industry professionals of the need to reduce the use of sand. Second, it is important to determine reactions upon learning of the crisis in order to generate interest and galvanize action. Third, determining the source of knowledge can help assess effective ways of broadly disseminating information to the construction industry.

The so-called sun, sea and sand tourism continues to be the type of tourism that fosters the greatest flow of passengers on an international scale, giving rise to an economic impact and job creation. However, like any other type of economic and human activity, it generates negative externalities that manifest themselves in environmental impacts. The One Planet Sustainable Tourism Programme led by The World Tourism Organization announces its new vision for global tourism– growing better, stronger, and balancing the needs of people, planet and prosperity.Beyond good intentions, with the Delphi technique as a tool, a first approach has been made to elucidate the environmental awareness of the sector, the commitment to develop and incorporate sustainable plans to behave in an ethical manner and contribute to economic development while the quality of the environment and local communities as a whole. 14 professionals were selected to participate in the Delphi, all from different companies worldwide focused on geographical areas intended for sun, sea and sand tourism. Obtaining as a response, still, a sector with very weak awareness that does not incorporate the environment into its operational structures, it does not take responsibility for its own actions nor future sustainable developments.

Sand is an indispensable natural resource for any society. Despite society’s increasing dependence on sand, there are major challenges that this industry needs to deal with: limited sand resources, illegal mining, and environmental impact of sand mining. The purpose of this paper is twofold: to present an overview of the sand market, highlighting the main trends and actors for production, export and import, and to review the main environmental impacts associated with sand exploitation process. Based on these findings, we recommend different measures to be followed to reduce negative impacts. Sand mining should be done in a way that limits environmental damage during exploitation and restores the land after mining operations are completed.

Sand is a scarce resource, extracted from rivers and coasts at rates that exceed its natural renewal. Yet, little is understood about the political economy of sand extraction, the livelihood vulnerabilities produced, or why sand grabbing is occurring at unprecedented rates in particular locations. Drawing together literature on global production network approaches in economic geography and debates on sustainable livelihoods in development geography-two literatures rarely in conversation with one another-we reveal the links between new, globalized, cross-border articulations of poverty and prosperity and the sand trade. We situate our sand case in Southeast Asia across three sites, namely, in Singapore, the world's top sand importer; Cambodia, a top-ten global exporter of sand; and an emerging exporter, Myanmar. We examine how sand mining affects, directly and indirectly, a range of livelihoods, specifically fisheries in Cambodia, riverbank agriculture in Myanmar, and migrant labor in Singapore. Drawing on our empirical work, we argue that linking these two literatures with empirical data on sand provides an approach that is broad in its connections and simultaneously grounded in specific practices, places, and people. This enables us to better account for often overlooked aspects in the production, erosion, and transfer of value. Key Words: global production networks, livelihoods, precarity, sand mining, Southeast Asia.

As one of the manufacturing industries with high energy consumption and high pollution, sand casting is facing major challenges in green manufacturing. In order to balance production and green sustainable development, this paper puts forward man–machine dual resource constraint mechanism. In addition, a multi-objective flexible job shop scheduling problem model constrained by job transportation time and learning effect is constructed, and the goal is to minimize processing time energy consumption and noise. Subsequently, a hybrid discrete multi-objective imperial competition algorithm (HDMICA) is developed to solve the model. The global search mechanism based on the HDMICA improves two aspects: a new initialization method to improve the quality of the initial population, and the empire selection method based on Pareto non-dominated solution to balance the empire forces. Then, the improved simulated annealing algorithm is embedded in imperial competition algorithm (ICA), which overcomes the premature convergence problem of ICA. Therefore, four neighborhood structures are designed to help the algorithm jump out of the local optimal solution. Finally, an example is used to verify the feasibility of the proposed algorithm. By comparing with the original ICA and other four algorithms, the effectiveness of the proposed algorithm in the quality of the first frontier solution is verified.

River sand supplies are decreasing due to overexploitation and illicit sand mining. One ton of Portland cement production (the main binder in concrete) emits about one ton of carbon dioxide into the atmosphere. Thus, this study replaced conventional cement and river sand (R sand) with recycled waste materials (fly ash and manufactured sand (M sand)). The concrete mix proportions were designed using M40 grade, and the Ordinary Portland cement (OPC) and R sand were replaced with 0–85 wt% of fly ash and 0-100 wt% of M sand. The concrete samples were tested for compressive strength after 3–90 days of curing. Furthermore, machine learning (ML) techniques were engaged to predict the compressive strength of the concrete samples using Extreme Gradient Boosting (XGBoost), Long Short-Term Memory (LSTM), Support Vector Machine (SVM), and Gaussian Process Regression (GPR). Besides, the concrete samples containing fly ash, M sand, and R sand were characterized for microstructures and elemental compositions using SEM-EDS. The results revealed improved concrete compressive strength by incorporating fly ash and M sand. After 28 days of curing, OPC and R sand were partially replaced with 25 and 50 wt% of fly ash and M sand attained the designed strength of M 40 grade concrete. XGBoost model yielded the most accurate performance metrics for forecasting the compressive strength in training and testing phases with R 2 values equal to 0.9999 and 0.9964, respectively, compared to LSTM, SVM, and GPR. Thus, the XGBoost approach can be a viable technique for forecasting the strength of concrete incorporating fly ash and M sand. SEM-EDS analyses revealed compact formations with high calcium and silicon counts. Thus, the XGBoost approach can be a viable technique for forecasting the strength of concrete incorporating fly ash and M sand.