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One of the sources for the increase in the carbon footprint on the earth is the manufacturing of cement, which causes a severer environmental impact. Abundant research is going on to diminish CO₂ content in the atmosphere by appropriate utilization of waste by-products of industries. Alkali-activated slag concrete (AASC) is an innovative green new concrete made by complete replacement of cement various supplementary cementitious raw materials. Concrete is a versatile material used in different fields of structures, so it is very important to study the durability in different exposures along with the strength. The purpose of this paper is to study the performance of AASC by incorporating quartz sand as fine aggregate under different exposure conditions.

The materials for this innovative AASC are selected based on preliminary studies and literature surveys. Based on numerous trials a better performance mix proportion of AASC with quartz sand is developed with 1:2:4 mix proportion, 0.8 alkali Binder ratio, 19 M of NaOH and 50% concentration of Na₂SiO₃. Subsequently, AASC cubes are prepared and exposed for 3, 7, 14, 28, 56, 90, 112, 180, 252 and 365 days in ambient, acid, alkaline, sulfate, chloride and seawater and tested for compressive strength. In addition, to study the microstructural characteristics, scanning electron microscope (SEM), energy dispersive X-ray analysis and X-ray diffraction analysis was also performed.

Long-term performance of AASC developed with quartz sand is very good in the ambient, alkaline environment of 5% NaOH and seawater with the highest compressive strength values of 51.8, 50.83 and 64.46, respectively. A decrease in compressive strengths was observed after the age of 14, 56 and 112 days for acid, chloride and sulfate exposure conditions, respectively. SEM image shows a denser microstructure of AASC matrix for ambient, alkaline of 5% NaOH and seawater.

The proposed AASC is prepared with a mix proportion of 1:2:4, so the other proportions of AASC need to verify. In general plain, AASC is not used in practice except in few applications, in this work the effect of reinforced AASC is not checked. The real environmental exposure in fields may not create for AASC, as it was tested in different exposure conditions in the laboratory.

The developed AASC is recommended in practical applications where early strength is required, where the climate is hot, where water is scarce for curing, offshore and onshore constructions exposed to the marine environment and alkaline environment industries like breweries, distilleries and sewage treatment plants. As AASC is recommended for ambient air and in other exposures, its implementation as a construction material will reduce the carbon footprint.

The developed AASC mix proportion 1:2:4 is an economical mix, because of low binder content, but it exhibits a higher early age compressive strength value of 45.6 MPa at the age of 3 days. The compressive strength increases linearly with age from 3 to 365 days when exposed to seawater and ambient air. The performance of AASC is very good in the ambient, alkaline environment and seawater compared to other exposure conditions.

The initiative for sustainability in the construction industry has led to the innovative utilization of automobile tire waste, transforming it into value-added products, toward decarbonization in the construction industry, aligning with the development and sustainability goals of Al-Kharj Governorate. However, the disposal of these materials generates significant environmental concerns. As a payoff for these efforts, this study aims to contribute to a fruitful shift toward eco-friendly recycling techniques, particularly by studying the transformation of tire waste bead wires into recycled steel tire fibers (RSTFs) for sustainable concrete composites.

This research delves into how this technological transformation not only addresses environmental concerns but also propels sustainable tire innovation forward, presenting a promising solution for waste management and material efficiency in building materials. Recent studies have highlighted the superior tensile strength of RSTFs from discarded tires, making them suitable for various structural engineering applications. Recently, there has been a notable shift in research focus to the use of RSTFs as an alternative to traditional fibers in concrete. In this study, however, efforts have paid off in outlining a comprehensive assessment to investigate the viability and efficacy of repurposing tire bead wires into RSTFs for use in concrete composites, as reported in the literature.

This study examined the Saudi waste management, the geometrical properties of RSTFs, and their impact on the strength properties of concrete microstructure. It also examined the economic, cost, and environmental impacts of RSTFs on concrete composites, underscoring the need for the construction industry to adopt more sustainable and adaptable practices. Furthermore, the main findings of this study are proposed insights and a blueprint for the construction industry in Al-Kharj Governorate, calling for collective action from both public and private sectors, and the community to transform challenges into job opportunities for growth and sustainability.

This study pointed to thoroughly demonstrate the technological advancement in converting tire waste to reinforcing fibers by evaluating the effectiveness, environmental sustainability, and practicality of these fibers in eco-friendly concrete composites. Besides, the desired properties and standards for RSTFs to enhance the structural integrity of concrete composites are recommended, as is the need to establish protocols and further study into the long-term efficacy of RSTF-reinforced concrete composites.

Low-carbon concrete represents a new direction in mitigating the global warming effects caused by clinker manufacturing. Utilizing Saudi agro-industrial by-products as an alternative to cement is a key support in reducing clinker production and promoting innovation in infrastructure and circular economy concepts, toward decarbonization in the construction industry. The use of fly ash (FA) as a cement alternative has been researched and proven effective in enhancing the durability of FA-based concrete, especially at lower replacement levels. However, at higher replacement levels, a noticeable impediment in mechanical strength indicators limits the use of this material.

In this study, low-carbon concrete mixes were designed by replacing 50% of the cement with FA. Varying ratios of nano-sized glass powder (4 and 6% of cement weight) were used as nanomaterial additives to enhance the mechanical properties and durability of the designed concrete. In addition, a 10% of the mixing water was replaced with EMs dosage.

The results obtained showed a significant positive impact on resistance and durability properties when replacing 10% of the mixing water with effective microorganisms (EMs) broth and incorporating nanomaterial additives. The optimal mix ratios were those designed with 10% EMs and 4–6% nano-sized glass powder additives. However, it can be concluded that advancements in eco-friendly concrete additive technologies have made significant contributions to the development of sophisticated concrete varieties.

This study focused at developing nanomaterial additives from Saudi industrial wastes and at presenting a cost-effective and feasible solution for enhancing the properties of FA-based concrete. It has also been found that the inclusion of EMs contributes effectively to enhancing the concrete's resistance properties.

The purpose of this paper is to combine the theory of planned behavior variables with norm activation model to predict the behavioral intention to build eco-friendly houses among adult house owners of Kerala. It was hypothesized that the moral obligation will mediate the relationship of both attitude and subjective norm toward the intention to build eco-friendly houses.

Data were collected from 269 adult house owners from Kerala with the help of structured questionnaires. Attitude toward eco-friendly houses was measured using semantic differential scale, subjective norm was measured using items adapted from Ajzen and Jansson and Dorrepaal, personal norm was measured using 7 items adapted from Jansson and Dorrepaal and behavioral intention to build eco-friendly house was measured using 14-item measures which probed the various characteristics of eco-friendly buildings. Data were analyzed using mediation analysis with the help of PROCESS macro plug-in of IBM SPSS.

The study revealed that the relationship between subjective norm and behavioral intention to construct eco-friendly houses was fully mediated by personal norm, and the relationship between attitude and behavioral intention was partially mediated by personal norm.

Eco-friendly houses or sustainable architecture is the requirement of the time. Psychology can play a major role in increasing the choice to opt an eco-friendly alternative. The present study tries to develop a green marketing strategy by understanding the influential psychological variables. The study points to the importance of personal moral obligation of the people in the choice of the eco-friendly houses. The study is limited in itself because it failed to consider any situational factors that may be influential in the intention to build an eco-friendly house.

Considering the immediacy and potency of global climate change and the role green architecture can play to reduce the impact of the blow, eco-friendly architecture is inevitable. Many psychological studies have been instrumental in shaping and changing individual behaviors. Considering these facts the present study aims to identify the role of psychological variables in determining the intention to build eco-friendly houses. This study will help in identifying the relevant personal variables that can promote eco-friendly construction.

This study aims to develop geopolymer concrete (GPC) using manufactured sand (M-sand) and recycled concrete aggregate (RCA) under different curing conditions. GPC is a sustainable construction material developed with industrial waste products such as fly ash to eliminate the use of cement in the production of concrete. GPC requires heat curing for the attainment of early age strength. The development of GPC under heat curing conditions is a hard process in practice. To overcome such circumstances, an attempt was made to develop the GPC under different curing conditions with the aid of coarse aggregate (CA) and RCA. The influence of different curing conditions on strength gain and microstructural characteristics of GPC is investigated. Mechanical properties of GPC such as compressive strength, tensile strength, flexural strength and elastic modulus are reported and discussed.

This study focuses on the assessment of mechanical and microstructure characterization of eco-efficient GPC developed with natural CA and RCAs. The required optimum quantity of binder, alkali activator, alkaline liquid to binder ratio and aggregates was determined by appropriate trials. Three types of curing methods, namely, ambient, oven and water, were used for the development of GPC mixes. Following the properties of RCA, it is realistic to substitute up to 40% of coarser aggregates as the resulting aggregate mix falls within the requirements of the analyzed mix.

Special attention is required for the mix with RCA because the mix’s consistency is affected by the high water absorption of the RCA mix. GPC specimens cured at ambient and water conditions exhibited marginal variation in the compressive strength for both CA and RCA. The compressive strength of GPC mixes prepared with RCA was marginally higher than that of the GPC made with CA under different curing regimes. RCA can be used as a sustainable material in lieu of CA in GPC.

The main significance of this research work is to develop the optimal mix design with appropriate mix proportion. The present study proposes a satisfactory methodology that enhances the mechanical strength of GPC as the guidelines are not available in the standards to address this problem. Effective use of waste materials such as fly ash and recycled aggregate for the development of GPC is another major research focus in the proposed investigation.

The urgency to address climate change and its devastating consequences has never been more pressing. As societies become increasingly aware of the detrimental impact of traditional housing on the planet, there is a growing demand for eco-friendly housing solutions that prioritize energy efficiency, resource conservation and reduced carbon emissions. Therefore, this study aims to investigate the factors that influence customers’ priority toward eco-friendly house purchasing intention.

This study collected 386 data using a quantitative research strategy and purposive sampling method. This study uses a hybrid analysis technique using partial least squares structural equation modeling (PLS-SEM) and fuzzy-set qualitative comparative analysis (fsQCA) approaches to identify the influencing factors.

The PLS-SEM analysis found that attitude toward the eco-friendly house, subjective norms, performance expectancy, environmental knowledge and environmental sensitivity have a positive influence on eco-friendly house purchasing intention. However, perceived behavioral control and willingness to pay were found to have insignificant effect on customers’ intention to purchase eco-friendly houses. The fsQCA results further revealed complex causal relationships between the influencing factors.

This research will not only contribute to academic knowledge but also provide practical guidance to real estate developers, policymakers and individuals looking to make environmentally responsible choices. By understanding the factors that influence consumers’ intentions to purchase eco-friendly houses, we can pave the way for a more sustainable and resilient future.

This study has used a hybrid analysis technique, combining PLS-SEM and fsQCA, to enhance the predictive accuracy of eco-friendly house purchase intentions among individuals residing in densely populated and highly polluted developing countries, such as Bangladesh.

The present work focuses on evaluating the physical and mechanical characteristics of geopolymer concrete (GPC) by replacing the sodium silicate waste (SSW) in place of traditional river sand. The aim is to create eco-friendly concrete that mitigates the depletion of conventional river sand and conserves natural resources. Additionally, the study seeks to explore how the moisture content of filler materials affects the performance of GPC.

SSW obtained from the sodium silicate industry was used as filler material in the production of GPC, which was cured at ambient temperature. Instead of the typical conventional river sand, SSW was substituted at 25 and 50% of its weight. Three distinct moisture conditions were applied to both river sand and SSW. These conditions were classified as oven dry (OD), air dry (AD) and saturated surface dry (SSD).

As the proportion of SSW increased, there was a decrease in the slump of the GPC. The setting time was significantly affected by the higher percentage of SSW. The presence of angular-shaped SSW particles notably improved the compressive strength of GPC when replacing a portion of the river sand with SSW. When exposed to elevated temperatures, the performance of the GPC with SSW exhibited similar behavior to that of the mix containing conventional river sand, but it demonstrated a lower residual strength following exposure to elevated temperatures.

Exploring the possible utilization of SSW as a substitute for river sand in GPC, and its effects on the performance of the proposed mix. Analyzing, how varying moisture conditions affect the performance of GPC containing SSW. Evaluating the response of the GPC with SSW exposed to elevated temperatures in contrast to conventional river sand.

This study investigated the potential of partially replacing cement with red mud (RM) in concrete and examined its effects on its mechanical properties and microstructure. This study aims to explore sustainable alternatives to traditional cement and evaluate the performance of concrete mixtures with varying percentages (%) of RM as cement replacement.

This research aims to comprehensively understand the impact of RM on concrete, aiming for both environmental sustainability and improved construction materials. Subsequently, concrete mixtures were prepared with varying RM contents, ranging from 0% to 21% in increments of 3%, replacing cement. The workability of these mixtures was evaluated using the Slump Cone Test, whereas their mechanical properties (compressive strength, flexural strength and split tensile strength) were assessed through standardized tests. The durability was further investigated via water absorption, acid attack, rapid chloride permeability tests, open porosity test and Sorptivity test. To gain deeper insights into the internal structure of concrete, microstructure analysis was conducted using X-ray diffraction and scanning electron microscopy. Finally, the results were analyzed and quantified.

The finding demonstrates that substituting 12% of cement with RM not only boosts the mechanical characteristics of concrete but also mitigates waste disposal. The microstructural analysis identified a denser cement matrix and improved bonding between the cement paste and the aggregates, suggesting potential improvements in strength and durability.

These results suggest that RM can be efficiently used to produce sustainable concrete with potential applications in construction projects with environmental considerations.

The purpose of this study is to use the corrected stress field theory to derive the shear capacity of geopolymer concrete beams (GPC) and consider the shear-span ratio as a major factor affecting the shear capacity. This research aims to provide guidance for studying the shear capacity of GPC and to observe how the failure modes of beams change with the variation of the shear-span ratio, thereby discovering underlying patterns.

Three test beams with shear span ratios of 1.5, 2.0 and 2.5 are investigated in this paper. For GPC beams with shear-span ratios of 1.5, 2.0 and 2.5, ultimate capacities are 337kN, 235kN and 195kN, respectively. Transitioning from 1.5 to 2.0 results in a 30% decrease in capacity, a reduction of 102kN. Moving from 2.0 to 2.5 sees a 17% decrease, with a loss of 40KN in capacity. A shear capacity formula, derived from modified compression field theory and considering concrete shear strength, stirrups and aggregate interlocking force, was validated through finite element modeling. Additionally, models with shear ratios of 1 and 3 were created to observe crack propagation patterns.

For GPC beams with shear-span ratios of 1.5, 2.0 and 2.5, ultimate capacities of 337KN, 235KN and 195KN are achieved, respectively. A reduction in capacity of 102KN occurs when transitioning from 1.5 to 2.0 and a decrease of 40KN is observed when moving from 2.0 to 2.5. The average test-to-theory ratio, at 1.015 with a variance of 0.001, demonstrates strong agreement. ABAQUS models beams with ratios ranging from 1.0 to 3.0, revealing crack trends indicative of reduced crack angles with higher ratios. The failure mode observed in the models aligns with experimental results.

This article provides a reference for the shear bearing capacity formula of geopolymer reinforced concrete (GRC) beams, addressing the limited research in this area. Additionally, an exponential model incorporating the shear-span ratio as a variable was employed to calculate the shear capacity, based on previous studies. Moreover, the analysis of shear capacity results integrated literature from prior research. By fitting previous experimental data to the proposed formula, the accuracy of this study's derived formula was further validated, with theoretical values aligning well with experimental results. Additionally, guidance is offered for utilizing ABAQUS in simulating the failure process of GRC beams.