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Given that many consumers are skeptical about environmentally based advertising campaigns, the purpose of this study is to propose an optimized message strategy to facilitate consumer engagement with green messages in social media contexts.

Four empirical studies are conducted using self-report questionnaires to test proposed hypotheses with a focus on the interplay between claim specificity and benefit appeals in green advertising on social media.

The current study examines the interaction effects of claim specificity and benefit appeals on consumer engagement in social media. Specifically, the results reveal that when the message claim is abstract, using other-benefit appeals produces more positive consumer engagement than using self-benefit appeals. Moreover, the results illustrate that self-enhancement motivates consumers to engage with green product advertising messages when the advertising appeal is abstract and the advertising message is associated with benefits for others. Finally, it is found that consumers’ self-construal level moderates the interaction effect of claim specificity and benefit appeals type on consumer engagement on social media.

This paper has practical implications to both social media managers and advertisers in the green product industry: a match with advertising claim specificity and construal level (i.e. social distance: self-benefit vs other-benefit) should be ensured to increase consumer engagement on social media. In addition, self-enhancement and self-construal should be considered for a better message strategy in social media contexts.

The findings make important contributions to the literature in that we extend the applications of construal level theory to social media contexts as a valid theoretical tool to identify optimized green message strategies. As such, it provides future researchers and practitioners in the domain of green campaigns with useful guidelines to boost more consumption of green products.

Utilization of sustainable materials is a global demand in the construction industry. Hence, this study aims to integrate waste management and artificial intelligence by developing an artificial neural network (ANN) model to predict the compressive strength of green concrete. The proposed model allows the use of recycled coarse aggregate (RCA), recycled fine aggregate (RFA) and fly ash (FA) as partial replacements of concrete constituents.

The model is constructed, trained and validated using python through a set of experimental data collected from the literature. The model’s architecture comprises an input layer containing seven neurons representing concrete constituents and two neurons as the output layer to represent the 7- and 28-days compressive strength. The model showed high performance through multiple metrics, including mean squared error (MSE) of 2.41 and 2.00 for training and testing data sets, respectively.

Results showed that cement replacement with 10% FA causes a slight reduction up to 9% in the compressive strength, especially at early ages. Moreover, a decrease of nearly 40% in the 28-days compressive strength was noticed when replacing fine aggregate with 25% RFA.

The research is limited to normal compressive strength of green concrete with a range of 25 to 40 MPa.

The developed model is designed in a flexible and user-friendly manner to be able to contribute to the sustainable development of the construction industry by saving time, effort and cost consumed in the experimental testing of materials.

Green concrete containing wastes can solve several environmental problems, such as waste disposal problems, depletion of natural resources and energy consumption.

This research proposes a machine learning prediction model using the Python programming language to estimate the compressive strength of a green concrete mix that includes construction and demolition waste and FA. The ANN model is used to create three guidance charts through a parametric study to obtain the compressive strength of green concrete using RCA, RFA and FA replacements.

The purpose of this paper is to develop new predictive models using gene expression programming in order to estimate the compressive strength of green concrete, as accurate models that can predict the compressive strength of green concrete are still lacking.

To estimate the compressive strength of plain concrete, fly ash concrete, silica fume concrete and concrete with silica fume and fly ash, four predictive GEP models are developed. The GEP models are developed using a large and reliable database that is collected from the literature. The GEP models are validated using the collected experimental database.

The R² is used to statistically evaluate the performance of the GEP models wherein the R² values for the GEP models including all data are 85, 95, 80 and 95.3 percent for the models that predict the compressive strength of plain concrete, fly ash concrete, silica fume concrete and concrete with silica fume and fly ash, respectively.

The GEP models have high R² values and low RMSE and MAE, which indicates that they are capable of predicting the compressive strength of green concrete with a reasonable accuracy.

Addressing global warming challenge, carbon emissions reduction potential of the construction industry has received additional attentions. The decoupling of construction industry and carbon emissions through policies, technologies and model innovations is an effective way for reducing environmental pollution and achieve eco-urban target. The paper aims to discuss these issues.

Within the scope of green building carbon emissions (GB-CO₂) research, a large number of scientific literature has been published in construction discipline over the past few decades. However, it seems that a systematic summary of strategies, techniques, models and scientific discussion of future direction of GB-CO₂ is lacking. Therefore, this paper carries out data mining on authoritative journals, identified the key research topics, active research areas and further research trends through visualization studies.

This study contributes to the body of knowledge in GB-CO₂ by critically reviewing and summarizing: professional high-quality journals have a greater influence in the scope of research, developed countries and developing countries are all very concerned about sustainable buildings, and the current hot topics of research focus on the application of the life cycle models, energy efficiency, environmental performance of concrete material, etc. Moreover, further research areas that could expand the knowledge of cross-national long-term carbon mechanisms, develop comprehensive life cycle carbon emissions assessment models, build technical standards and tests for the sustainable building material and systems, and exploit multi-objective decision models considering decarbonizing design and renewable energy.

This study is of value in systematic insight the state-of-the-art of GB-CO₂ research in the more recent decade. A more vividly and effectively method is documented in extending the traditional bibliometric review to a deeper discussion. This study can also benefit construction practitioners by providing them a focused perspective of strategy and technologies innovations for emerging practices in green building projects.

This paper aims to investigate the use of calcined mussel shell (CMS) ash–cement mix in concrete that is found to increase the concrete resistance against carbonation.

The deposited ash from the calcination of the mussel shells at 1000°C was used to replace the ordinary Portland cement at 5 and 7 per cent of the cement weight. The test results from the control concrete specimens were compared to the test results from the experimental concrete specimens to analyse the effects due to the said replacements. Carbonation was carried out naturally in the environment where the concentration of the carbon dioxide gas was at 0.03 per cent, the relative humidity of 65 per cent and the temperature of 27°C for a maximum period of 120 days. Measurement of carbonation depth was taken in accordance to the BS EN 13295: 2004. The carbonation resistance of the concrete was assessed based on the degree of compliance with the common design life requirement of 50 years. The filler effect from the CMS was verified using the capillary absorption test (ASTM C1585: 2013) and the electron microscope.

Experimental concrete specimens containing 5 and 7 per cent of the CMS ash demonstrated better carbonation resistance compared to the control concrete specimens with a minimum attainable design life of 56 years which can reach a maximum of 62 years. Capillary absorption test results indicated that the concrete pores have been effected by the said filler effect and visual observation from the electron microscope confirmed, solidifying the statement.

The CMS ash is proven to contribute to the concrete’s resistance against carbonation. Also, the CMS ash is synthesized from waste materials which have contributed to the application of the green material in the concrete technology.

The change in climate and depletion of natural resources because of the harmful emissions from different materials becomes a main issue for the globe. Some of the developed and developing countries have focused on this issue and performed research to provide a solution. The purpose of this study is to identify the best types of concrete based on its impact on the environment and economy.

The life cycle assessment and life cycle cost analysis of six concrete mixtures that include construction and demolition wastes (CDW), marble sludge, rice husk and bagasse ash as a partial replacement of cement, are performed. These types of concrete are compared with each other and with ordinary concrete to select the best possible concrete type for a developing country, like Pakistan.

The results show that, although for an agricultural country like Pakistan, the agriculture wastes such as rice husk and bagasse ash are preferable to be used, if the emissions of CO₂ and CO from rice husk and NOx and SO₂ from bagasse ash are properly controlled. However, based on the results, it is recommended to use the CDW in concrete because of the small amount of air emissions and affordable prices.

Through this study, a path has been provided to construction companies and relative government organizations of Pakistan, which leads to sustainable practices in the construction industry. Moreover, the base is provided for future researchers who want to work in this area, as for Pakistan, there is no database available that helps to identify the impact of different concrete on the environment.

Environmental issues caused by the production of Portland cement have led to it being replaced by waste materials such as fly ash, which is more economical and safer for the environment. Also, fly ash is a material with sustainable properties. Therefore, this paper aims to focus on the development of sustainable construction materials using 100% high-calcium fly ash and potassium hydroxide (KOH)-based alkaline solution and study the engineering properties of the resulting fly ash-based geopolymer concrete. Laboratory tests were conducted to determine the mechanical properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In phase I of the study, carbon nanotubes (CNTs) were added to determine their effect on the strength of the geopolymer mortar. The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce similar (comparable) strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates a considerable amount of heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond was unable to form a stronger bond. This study also determined that the addition of CNTs to the mix makes the geopolymer concrete tougher than the traditional concrete without CNT.

Tests were conducted to determine properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In Phase I of the study, CNTs were studied to determine their effect on the strength of the geopolymer mortar.

The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce the same strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates too much heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond. This study also determined that the addition of CNTs to the mix makes the concrete tougher than concrete without CNT.

This study was conducted at the construction engineering and management concrete laboratory at North Dakota State University in Fargo, North Dakota. All the experiments were conducted and analyzed by the authors.

The purpose of this paper is to identify the sustainability conditions of primary schools in Turkey within the scope of the life cycle assessment (LCA). It is aimed to develop optimum alternatives to reduce the environmental impact of primary schools and reach environmental sustainability targets of the sustainable development goals in Turkey.

From the construction project of 103 buildings located in Istanbul, 10 case buildings with various typical plans were chosen for analysis. The results regarding their life cycle energy and carbon emission for material production, operation and maintenance stages were calculated for a lifespan of 50 years. Results were evaluated and compared within the scope of environmental sustainability. Optimum alternatives for improving the environmental sustainability and performances of selected case buildings’ facades were developed, and the life cycle energy and carbon emission for proposed conditions were calculated. The obtained results were evaluated for current and proposed conditions.

Results showed that reinforced concrete material contributes the most to the life cycle-embodied energy and CO₂ emission of buildings. Cooling load increases the life cycle operational energy (LCOE) and CO₂ emission of buildings. Using high-performance glazing significantly reduces LCOE and CO₂ emission. Recycled and fiber-based materials have significant potential for reducing life cycle-embodied energy and CO₂ emission.

This study has been developed in response to achieving sustainable development targets on public buildings in Turkey. In this regard, external walls of primary schools were analyzed within the scope of LCA and recommendations were made to contribute to the policies and regulations requested by the Government of Turkey. This study proves that alternative and novel materials have great potential for achieving sustainable public buildings. The study answers to questions about reducing the environmental impact of primary school buildings by using LCA approach with a holistic point of view.

Fire can severely affect concrete structures and with knowledge of the properties of materials, the damage can be assessed. Aggregate, cement matrix and their interaction are the most important components that affect concrete behaviour at high temperatures. The effect of incorporating recycled concrete aggregate or cementitious materials, namely, cement type and pulverized fly ash, are reviewed to provide a better understanding of their involvement in fire resistance.

More investigation research is needed to understand the fire resistance of such sustainable concrete that was already constructed. The present study illustrates the effect of using recycled concrete aggregate and cementitious materials on the fire resistance of concrete. To do so, a literature review was conducted and relevant data were collected and presented in a simple form. The author's selected research findings, which are related to the presents study, are also presented and discussed.

Recycled concrete aggregate enhances the concrete behaviour at high temperatures when it substitutes the natural aggregate by reasonable substitution (more than 25–30%). It also almost eliminates the possibility of spalling. Moreover, utilizing both supplementary cementitious materials with recycled concrete aggregate can improve the fire resistance of concrete. The incorporation of pulverized fly ash and slag in Portland cement or blended cement can generally keep the mechanical properties of concrete at a higher level after heating to a high temperature.

Recycled concrete aggregate enhances the concrete behaviour at high temperatures when it substitutes the natural aggregate by reasonable substitution (more than 25–30%). It also almost eliminates the possibility of spalling. Moreover, utilizing both supplementary cementitious materials with recycled concrete aggregate can improve the fire resistance of concrete. The incorporation of pulverized fly ash and slag in Portland cement or blended cement can generally keep the mechanical properties of concrete at a higher level after heating to a high temperature.

Bioconcrete is widely believed to be environmentally beneficial over conventional concrete. However, the process of bioconcrete production involves several steps, such as waste recovery and treatment, that potentially present significant environmental impacts. Existing life-cycle assessments of bioconcrete are limited in the inventory and impact analysis; therefore, they do not consider all the steps involved in concrete production and the corresponding impacts. The purpose of this study is to extensively study the cradle-to-gate environmental impacts of all the production stages of two most common bioconcrete types (i.e. sludge-based bioconcrete and cement kiln dust-rice husk ash (CKD-RHA) bioconcrete) as opposed to conventional concrete.

A cradle-to-gate life-cycle assessment process model is implemented to systematically analyze and quantify the resources consumed and the environmental impacts caused by the production of bioconcrete as opposed to the production of conventional concrete. The impacts analyzed in this assessment include global warming potential, ozone depletion potential, eutrophication, acidification, ecotoxicity, smog, fossil fuel use, human toxicity, particulate air and water consumption.

The results indicated that sludge-based bioconcrete had higher levels of global warming potential, eutrophication, acidification, ecotoxicity, fossil fuel use, human toxicity and particulate air than both conventional concrete and CKD-RHA bioconcrete.

The contribution of this study to the state of knowledge is that it sheds light on the hidden impacts of bioconcrete. The contribution to the state of practice is that the results of this study inform the bioconcrete production designers about the production processes with the highest impact.