Extended theory of planned behaviour for promoting construction waste recycling in Hong Kong

Investigating industry 4.0 technologies in logistics 4.0 usage towards sustainable manufacturing supply chain

In the era of Industry 4.0 (I4.0), automation and data analysis have undergone significant advancements, greatly impacting production management and operations management. Technologies such as the Internet of Things (IoT), robotics, cloud computing (CC), and big data, have played a crucial role in shaping Logistics 4.0 (L4.0) and improving the efficiency of the manufacturing supply chain (SC), ultimately contributing to sustainability goals. The present research investigates the role of I4.0 technologies within the framework of the extended theory of planned behavior (ETPB). The research explores various variables including subjective norms, attitude, perceived behavior control, leading to word-of-mouth, and purchase intention. By modeling these variables, the study aims to understand the influence of I4.0 technologies on L4.0 to establish a sustainable manufacturing SC. A questionnaire was administered to gather input from small and medium-sized firms (SMEs) in the manufacturing industry. An empirical study along with partial least squares structural equation modeling (SEM), was conducted to analyze the data. The findings indicate that the use of I4.0 technology in L4.0 influences subjective norms, which subsequently influence attitudes and personal behavior control. This, in turn, leads to word-of-mouth and purchase intention. The results provide valuable insights for shippers and logistics service providers empowering them to enhance their performance and contribute to achieving sustainability objectives. Consequently, this study contributes to promoting sustainability in the manufacturing SC by stimulating the adoption of I4.0 technologies in L4.0.

Empirical and simulated investigation of the solid waste reverse supply chain: A complex adaptive system perspective

Solid waste is increasing rapidly worldwide. In this study, the solid waste (household waste, construction and demolition waste and industrial waste) management systems are treated as reverse supply chain to analyze the critical operational issues based on complex adaptive system theory. At the single-layer, the complexity of the various nodes at a layer arises from rational decision-making and behavioral heterogeneity. The solid waste generation layer is employed as an example to investigate the complexity of node behavioral decisions. Regression analysis results reveal that both endogenous (Attitude, Subjective norm, and Perceived behavioral control) and exogenous factors (Economic incentive, Government supervision, Technical support) positively influence sorting behavior. The effect of Economic incentive (β=0.327P<0.001) and Attitude (β=0.249P<0.001) on sorting behavior are the largest. In the multi-layer system, different layers communicate with each other through the material and financial flows and have cross-layer impacts. An agent-based model is developed to investigate the multi-layer feedforward influence mechanism of changes in key layers (e.g., sorting rate, disposal rate) and the material and financial flows adaptive adjustment direction of the solid waste reverse supply chain. High rate of participation and accuracy of source sorting can shorten material flow paths and reduce storage and transportation costs. The increase in disposal rate encourages the transition of solid waste from backfill to resource utilization. This study provides a practice reference for solid waste reverse supply chain and related enterprises managers.

Exploring Physical Education Teachers' Intention and Perceived Constraints in Offering Online Lessons Using the Theory of Planned Behavior: A Multi-Country Analysis

Guided by the theory of planned behavior, this study aimed to determine the influence of Physical Education (PE) teachers' attitudes, their perceived behavioral control, and the influence of subjective norms on their intention and constraints (intrapersonal, interpersonal, and structural) to offer a high-quality class based on best practices to deliver PE lessons online during the COVID-19 pandemic. This cross-sectional, multi-country survey study recruited PE teachers from five countries (China, Malaysia, the Philippines, Turkey, and the United States). A total of 928 online questionnaires were used in the analysis. In terms of the overall intention to teach online, our findings showed that American and Filipino teachers had higher levels of intention to continue teaching online. In contrast, Turkish, Malaysian, and Chinese teachers showed a lower interest. Moreover, Malaysian teachers had more intrapersonal constraints while the teachers in the other four countries were not as restrained intrapersonally. The results highlight the significant influence of perceived behavioral control and attitudes on PE teachers' intention to deliver online courses. Constraints to online teaching had a considerably large negative impact on attitudes, subjective norms, and perceived behavioral control. Based on the results, the proposed extension to the theory of planned behavior was an appropriate framework for understanding the behavioral intent of PE teachers.

Application of Bayesian structural equation modeling in construction and demolition waste management studies: Development of an extended theory of planned behavior

Sustainable construction and demolition waste management relies heavily on the attitudes and actions of its constituents; nevertheless, deep analysis for introducing the best estimator is rarely attained. The main objective of this study is to perform a comparison analysis among different approaches of Structural Equation Modeling (SEM) in Construction and Demolition Waste Management (C&DWM) modeling based on an Extended Theory of Planned Behaviour (Extended TPB). The introduced research model includes twelve latent variables, six independent variables, one mediator, three control variables, and one dependent variable. Maximum likelihood (ML), partial least square (PLS), and Bayesian estimators were considered in this study. The output of SEM with the Bayesian estimator was 85.8%, and among effectiveness of six main variables on C&DWM Behavioral (Depenmalaydent variables), five of them have significant relations. Meanwhile, the variation based on SEM with ML estimator was equal to 78.2%, and four correlations with dependent variable have significant relationship. At the conclusion, the R-square of SEM with the PLS estimator was equivalent to 73.4% and three correlations with the dependent variable had significant relationships. At the same time, the values of the three statistical indices include root mean square error (RMSE), mean absolute percentage error (MPE), and mean absolute error (MSE) with involving Bayesian estimator are lower than both ML and PLS estimators. Therefore, compared to both PLS and ML, the predicted values of the Bayesian estimator are closer to the observed values. The lower values of MPE, RMSE, and MSE and the higher values of R-square will generate better goodness of fit for SEM with a Bayesian estimator. Moreover, the SEM with a Bayesian estimator revealed better data fit than both the PLS and ML estimators. The pattern shows that the relationship between research variables can change with different estimators. Hence, researchers using the SEM technique must carefully consider the primary estimator for their data analysis. The precaution is necessary because higher error means different regression coefficients in the research model.

Optimal site selection for construction and demolition waste disposal using GIS-FAHP: a case study from Kafr El Sheikh City, Egypt

The increasing number of building and demolition projects results in huge amounts of construction and demolition wastes (CDWs) that are illegally dumped. However, these wastes must be disposed of in appropriate legal sites to protect the environment and human health. After reviewing the literature, no prior research examined optimal site selection for dumping or recycling CDW in an Egyptian city. Furthermore, the absence of field surveys did not offer a holistic understanding of the specific criteria used in the model for this region, nor did it permit an assessment of the suitability of existing dumpsites, thereby revealing certain limitations in the final results. In this regard, this research aims to apply a multi-criteria geographic information system (GIS)-based framework to identify an optimal site for CDW disposal in Kafr El Sheikh City. The criteria affecting the site selection are identified and categorized from prior literature, which are further refined using field surveys and focus group to evaluate their applicability in the context of an Egyptian city. After conducting questionnaire surveys, the trapezoidal interval type II fuzzy analytic hierarchy process is applied to compute the weights of the identified criteria from the perspective of each group of experts. The entropy-based aggregation approach is employed to identify the compromise weights taking into account the preferences of different groups. GIS is a powerful tool for geoprocessing and analyzing spatial big data. The result is a scenario map for the optimal site locations with varying suitability scales (i.e., excellent, very good, good, average, poor, and very poor). The proposed methodology provides what-if scenarios based on a selected set of criteria. According to the results of the multi-criteria decision analysis models, the suitability varies based on the weights of the criteria. For the equal-weighted criteria model, the excellent category covers 5.96% of the study area, increasing to 6.48% for the weighted criteria model. These areas primarily lie in the northeast direction. Conversely, the majority of the study area, 41.80% under equal-weighted criteria and 32.39% under weighted criteria, falls within the average and poor suitability categories, respectively. In general, the most suitable areas are located on the outskirts of the city, and the suitability decreases near the central business district. To bridge the gap between research findings and practical applications, a land use analysis employing satellite imagery is conducted to pinpoint suitable locations for CDW disposal. Existing CDW dumpsites predominantly fall within the range of poor to very good for the equal-weighted criteria model, while the weighted criteria model categorizes them into the poor (16.66%) and average (83.33%) categories. The findings demonstrated the applicability of the proposed framework for CDW disposal management and planning.

Research on the driving path of carbon inclusive system to green behavior of the public: based on procedural grounded theory and multiple intermediary model

As an emerging carbon emission reduction mechanism, the carbon inclusive system (CIS) develops an important effect in promoting public green behavior and has been piloted in some provinces and cities in China. Under this background, this paper deeply analyzes the public's attitude towards CIS and its influencing factors based on the grounded theory and 1120 questionnaires, and comprehensively discusses the action path of CIS on public green behavior by using multiple regression model, bootstrap method, and placebo test. The results show that CIS can promote the public to implement green behavior, and system operation, internal psychology, and government behavior are important factors that affect the incentive effect of CIS. Among them, incentive effect and green willingness play multiple intermediary and chain intermediary roles in the path of CIS on green behaviors. Further heterogeneity analysis shows that the influence path of CIS on green behavior is different among diverse gender groups, incentive choice preference groups, and family types. This study has reference value for improving the design of CIS and constructing diversified incentive mechanism of CIS.

Stakeholders' purchase intention of products with recycled content: a combination of SEM and BPNN approach

The rapid urban renewal progress has generated a large amount of construction and demolition (C&D) waste in China. According to the concept of circular economy (CE), producing products with recycled content (PwRC) is an effective solution to achieve sustainable C&D waste management. However, the low market acceptance of PwRC affects stakeholders' purchase intention, which hinders the development of the PwRC industry. In order to clarify the stakeholders' purchase intention and investigate the influencing mechanism of stakeholders' purchase intention, a novel method which combines structural equation modeling (SEM) with a back-propagation neural network (BPNN) is proposed. The method makes full use of the causal analysis ability of SEM and the nonlinear characteristics of BPNN to simulate and to verify the path of product cues, perceived value, and behavioral intention of stakeholders. The results reveal that the brand and materials of PwRC can affect stakeholders' perceived value, and in turn, affect their purchase intention. Focus on the brand and materials of PwRC will help recycled product manufacturers and governments to promote stakeholders' purchase intention and the development of the C&D waste recycled products market.

Researcher Perceptions of Involving Consumers in Health Research in Australia: A Qualitative Study

There is growing recognition internationally of the importance of involving consumers, patients, and the public in research. This is being driven by political mandates for policies, funding, and governance that demand genuine and meaningful engagement with consumers. There are many potential benefits to involving consumers in research, including an increased relevance to patient needs, improved quality and outcomes, and enhanced public confidence in research. However, the current literature highlights that efforts to incorporate their contributions are often tokenistic and there is a limited understanding of the psychological factors that can impact researcher attitudes, intentions, and behaviours when working with consumers in research. To address this gap, this study conducted 25 semi-structured interviews with health researchers in Australia using the qualitative case study method. The study aim was to explore the underlying influences on researcher behaviour when involving consumers in health research. The results identified several factors that influence researchers' behaviour, including better quality research, emotional connection and the humanisation of research, and a shift in research culture and expectations as major drivers. However, beliefs that consumers would hinder research and must be protected from risks, paternalism, and a lack of researcher skills and resources were identified as major barriers. This article presents a theory of planned behaviour for consumer involvement in the health research model. The model offers a valuable tool for policymakers and practitioners to understand the factors that influence researcher behaviours. It can also serve as a framework for future research in this area.

Reverse supply chain practices for construction and demolition waste in the Brazilian Amazon: a multi-stakeholder view

Construction and demolition waste (CDW) is an environmental problem that affects all regions of the world. Particularly in the Brazilian Amazon Forest region, the volume of CDW generated almost doubled between 2007 and 2019. Indeed, despite Brazil having environmental regulations for waste management, these have been insufficient to solve the environmental problem because there is no CDW reverse supply chain (RSC) properly developed in the Amazon region. Previous studies have proposed a conceptual model of a CDW RSC but have hitherto failed to apply them against real world practice. This paper, therefore, attempts to test existing conceptual models that describe a CDW RSC against real industry practice prior to developing an applied model of a CDW RSC for the Brazilian Amazon. To modify the conceptual model for CDW RSC, qualitative data through 15 semi-structured interviews with five different types of stakeholders of the Amazonian CDW RSC were collected and analyzed using qualitative content analysis methods using NVivo software. The proposed applied model includes present and future reverse logistics (RL) practices, and strategies and tasks necessary for the implementation of a CDW RSC in the city of Belém of Pará, in the Brazilian Amazon. Findings reveal that several overlooked problems, particularly the limitations of the existing legal framework in Brazil, are not enough to promote a robust CDW RSC. This is perhaps the first study to examine CDW RSC in the Amazonian rainforest. Arguments provided in this study highlight the necessity for an Amazonian CDW RSC that must be promoted and regulated by the government. This can be addressed by the utilizing public-private partnership (PPP) for developing a CDW RSC.

Experimental Evaluation of New Geopolymer Composite with Inclusion of Slag and Construction Waste Firebrick at Elevated Temperatures

This study investigates the effect of elevated temperatures on slag-based geopolymer composites (SGC) with the inclusion of firebrick powder (FBP). There is a limited understanding of the properties of SGC with the inclusion of FBP when exposed to elevated temperatures and the effects of cooling processes in air and water. In this regard, in the preliminary trials performed, optimum molarity, curing temperature, and curing time conditions were determined as 16 molarity, 100 °C, and 24 h, respectively, for SGCs. Then, FBP from construction and demolition waste (CDW) was substituted in different replacement ratios (10%, 20%, 30%, and 40% by slag weight) into the SGC, with optimum molarity, curing temperature, and curing time. The produced SGC samples were exposed to elevated temperature effects at 300, 600, and 800 °C and then subjected to air- and water-cooling regimes. The ultrasonic pulse velocity, flexural strength, compressive strength, and mass loss of the SGCs with the inclusion of FBP were determined. In addition, scanning electron microscopy (SEM) analyses were carried out for control (without FBP) and 20% FBP-based SGC cooled in air and water after elevated temperatures of 300 °C and 600 °C. The results show that the compressive and flexural strength of the SGC samples are higher than the control samples when the FBP replacement ratio is used of up to 30% for the samples after the elevated temperatures of 300 °C and 600 °C. The lowest compressive and flexural strength results were obtained for the control samples after a temperature of 800 °C. As a result, the elevated temperature resistance can be significantly improved if FBP is used in SGC by up to 30%.

Religious values and social distance as activators of norms to reduce food waste when dining out

Empirical research is required to identify psychological and psychographic factors which can activate or amplify norms of foodservice customers towards food waste reduction. By surveying 446 foodservice customers in Poland, a country with a large population of religion followers, this study examines the influence of religious values on personal norms and explores the moderating effect of social distance on injunctive norms. The results indicate that religious values do not activate personal norms directly but affect them indirectly via such mediating factors as the feeling of compassion and family upbringing. Close encounters, such as family and friends, amplify the effect of injunctive norms while distant encounters, such as fellow countrymen, do not. This suggests that measures for food waste reduction should be designed to appeal to the foodservice customers' feeling of compassion. The measures should also remind foodservice customers that their (grand)parents and friends would disprove food waste.

Evaluation of the household solid waste mandatory sorting policy in Shanghai: A 1-year public opinion survey

Sustainable management of household solid waste (HSW) is an essential step in realizing the development of a circular economy (CE). However, for many developing countries, HSW sorting is evolving incrementally, and focusing on the intervention role of policy and the sorting behaviour of residents can help achieve sustainable waste management. This study aims to investigate the main determinants of residents' HSW sorting behaviour and how policy particularly contributes to it. Drawing upon the theory of planned behaviour (TPB) and incorporating experiences, a conceptual framework is tested on a sample of Chinese residents in Shanghai (n = 560, from November to December 2020) using structural equation modelling analysis. The empirical results show that experience and behavioural intention greatly influence HSW sorting behaviour. Moreover, the positive attitude of residents promotes the success of HSW sorting. Subjective norms and perceived behaviour control indirectly affect behavioural intention and behaviour via attitude. The findings of this study provide policymakers with critical factors for the successful implementation of HSW sorting. We also propose policy implications to maintain and improve sorting efficiency from the perspective of residents (education, communication and publicity), neighbourhood committees (degree and efficiency of supervision) and property management companies (good infrastructure, services and processes).

Evolution game analysis on behavioral strategies of multiple stakeholders in construction waste resource industry chain

Rapid urbanization in China in recent years has led to a dramatic increase in the number of construction engineering projects and amount of construction waste, and the resource utilization of construction waste is an effective way to low-carbon and energy conservation construction. However, the nation has experienced a low utilization rate of construction waste resources, slow development of its construction waste recycling industry chain in various areas, low coordination of various stakeholders in the industry chain, and incomplete industry chain management. Therefore, in this study, a game model is first used to analyze the decision-making game and its stability strategy among multiple stakeholders in the recycling of construction waste. An income matrix of the three parties, i.e., the government, construction companies, and recycling enterprises, in the construction waste industry chain is then established and the Jacobi matrix used to obtain their evolution and stability strategy (economic incentives, green production, and scale-up). Finally, conclusions are drawn from the simulation analysis of the model: (1) The ratio between fine and subsidy should be reasonably controlled such that the recycling of construction waste by the construction companies is positively related to government supervision. (2) The inflow of renewable products into the market should be promoted to change the perception of the public. (3) A new mode of construction waste management should be developed to link various stakeholders in the industry chain. This study provides scientific and reasonable management suggestions in line with the actual situation of China and provides a useful reference for local government to choose appropriate policies to address the problem of construction waste recycling industry chain.

The Supervision Mechanism of Residents' Waste Separation Behavior: Analysis Using a Tripartite Evolutionary Game Model

To promote residents' waste separation behavior, waste separation supervision has been a crucial need. This paper aims to explore the supervision mechanism of residents' waste separation behavior using a tripartite evolutionary game model. The evolutionary stability conditions of resident, property service enterprise, and the government were analyzed. The influences of the main parameters on the strategy of three stakeholders were explored through numerical simulation. The results show that the regulatory mechanism of waste separation will reach the optimal stable strategy when the following conditions are satisfied: (1) the penalty for nonclassification is higher than the difference between classification cost and the total benefit of classification; (2) the subsidy to property services enterprise is greater than the total cost of positive participation management. Residents' behaviors are mainly influenced by rewards and punishments. The behavioral strategies of property service companies are more sensitive to subsidies than penalties. In the early stage of mandatory waste separation, it is important to reduce the cost of residents' separation, develop the publics' environmental awareness, and increase the willingness of properties to participate in management. This paper presents a new perspective and theoretical guidelines for the local government and communities to supervise residents' waste separation behaviors in China and other developing countries and offers useful insights into waste separation management for other countries.

Community Safety Behavior in Response to Coronavirus Pandemic

The purpose of this study is to explore the behavior and lifestyle of individuals in response to the coronavirus that the safety behavior of people in the coronavirus disease of 2019 pandemic. Hence, the study integrates the theory of planned behavior and the health belief model to understand the behavioral change in response to the coronavirus pandemic. The current study is qualitative therefore, a survey-based online questionnaire was used for data collection from university students and staff (faculty and nonfaculty) residing in top-tier cities of Pakistan, nonprobability convenient sampling was used to approach the audience. A two-stage approach was used to test the model using partial least square (variance-based structural equation modeling). The reliability and validity of the measurement model indicate that the data is reliable and valid. Outcomes prove all the relationships as proposed by the study, except for the impact of perceived barriers on intention and individual safety behavior. Perceived barriers act as obstacles that abstain individuals from following the standard operating procedures. The research agenda provides new insights into the fields of marketing, health care, consumer behavior, and behavioral studies. It contributes to the existing literature in the field of social marketing by studying the behavior and changes in the behavior of people in the global pandemic.

Waste management and green technology: future trends in circular economy leading towards environmental sustainability

The effective treatment of waste to be used as a resource in future has a major role in achieving environmental sustainability and moving towards circular economy. The current research is aimed to provide in-depth detail regarding prominent trends and research themes, evolution, future research orientation, main characteristics, and mapping of research publications on waste management, technological innovation in circular economy domain from the year 2000 to 2021. Different analyses including text mining and bibliometric and content analyses were applied to answer the research question and provide the details on aforementioned variables. From the bibliometric analyses, a total of 1118 articles were drawn out from the Scopus database to conceptualize the core body of research. As a result, the following themes were identified: electronic waste, circular economy transition, plastic waste, bio-based waste management, lifecycle assessment, and ecological impacts, and construction and demolition waste management. The highlighted features, future research orientation, and prominent research perspective can provide guideline for future research to enrich the literature through conducting studies on provided research directions and help lead waste management and technological innovation policymakers, professionals, and practitioners in moving towards circular transition.

What Influences Home Gardeners’ Food Waste Composting Intention in High-Rise Buildings in Dhaka Megacity, Bangladesh? An Integrated Model of TPB and DMP

Composting is a sustainable way of transforming organic waste into valuable organic fertilizers which have the potential to act as soil conditioners by controlling various biological processes. The prime objective of the current study was to determine the influencing factors behind the intent of home food waste composting, by employing the combined model of Theory of Planned Behavior (TPB) and Dualistic Passion Model (DMP). The combined model showed a higher predictive ability in comparison to the individual TPB model. The fit statistic of the integrated model was deemed good, and 65% of the variance for home composting intention was explained. Using a face-to-face questionnaire survey, a total of 203 valid responses were gathered from home gardeners and tested via a unique two-step methodology: the PLS-SEM and the artificial neural network (ANN). The results revealed that the composting intention can be significantly influenced by attitude, subjective norms, and perceived behavioral control. The study also confirmed the positive effect of harmonious passion and the negative effect of obsessive passion on the intention of food waste composting. Furthermore, the hybrid method produced more reliable results because HP was found to be the most important variable in both ANN and PLS-SEM results, while PBC was observed to be the second most important variable in ANN and the fourth most important in PLS-SEM. The results of the current study not only highlight the importance of passion in determining food waste composting intention in Dhaka, Bangladesh, but also provide helpful information for designing effective, sustainable tactics for encouraging residents to compost food waste at home.

Mechanism of Undergraduate Students’ Waste Separation Behavior in the Environmentally Friendly Higher Education Mega Center of Guangzhou

The volume of waste produced by aspects of both industrial life and daily life has increased in the past few years in conjunction with the rapidly growing economy in China. In urban areas, citizens consume more resources and produce much waste, which pollutes the environment. Many cities have proposed numerous regulations for waste separation to help build environmentally friendly cities. Plenty of studies tried to reveal the mechanism of residents’ waste separation behavior in different theoretical perspectives but were unable to clarify the effect of waste separation factors in university. Moreover, the response and performance of undergraduate students after the waste separation regulations are proposed and are not well discussed. To clarify the mechanism of waste separation behavior in campus and evaluate the response and performance, in this study, a questionnaire is used to sample undergraduate students from the Higher Education Mega Center in Guangzhou. With the use of SPSS 23.0, this study conducts an empirical analysis; the results of which show that (1) environmental awareness and personal responsibility have a significant positive impact on behavior attitude; (2) convenience and economic cost have a significant positive impact on perceived behavior control; (3) intention has a partial mediating role between behavior attitude, subjective norms, and perceived behavior control; and (4) habits directly affect behavior and regulate the relationship between intention and behavior. The results will provide some meaningful implications for the government.

Management system for engineering and decoration waste: An exploratory study in Shenzhen

Rapid urban development and renewal have caused large amounts of engineering and decoration waste to be produced. These wastes pose serious risks to the environment. Disposal and management of this waste have become problematic. A mean of 11.4 × 10⁶ m³ of engineering and decoration waste will be produced each year in Shenzhen between 2018 and 2035. Engineering and decoration waste are currently mainly sent to landfill, but this requires large amounts of land and can cause serious environmental pollution. There are problems including irregular emissions, a disorderly transportation market, and inadequate disposal facilities, so policies for managing engineering and decoration waste need to be established. In this study, a hybrid approach was used to develop a system for managing the whole engineering and decoration waste system (generation, collection & transportation, and disposal). The system was developed after determining waste emission and disposal requirements through site visits, clarifying problems involved in waste collection and transportation through interviews, identifying suitable management practices in an expert seminar, and developing a management system through desktop surveys. It was found that new buildings produce 0.02-0.04 (m³ waste)/(m² building) and 0.11-0.13 (m³ decoration waste)/(m² building) and that emission limits are required. Construction enterprises employ private trucks to transport waste, and illegal dumping occurs. Directed collection and transportation is required. Public welfare requires a mechanism for managing engineering and decoration waste with clear responsibilities. Government-authorized construction and operation should be explored and implemented. A propagable engineering and decoration waste management system is proposed with three management modules, generation, collection & transportation, and disposal, to act as a strategy for improving engineering and decoration waste.

Intention to comply with solid waste management practices among households in Butajira town, Southern Ethiopia using the theory of planned behavior

Background

One of the world’s most serious environmental issues is solid waste management. It is critical for researchers to understand the intention to comply with solid waste management. Thus, we aim to determine the intention to comply with solid waste management practice among households in Butajira Town using the Theory of Planned Behavior.

Method

A community-based cross-sectional study was conducted on a sample of 422 households in Butajira from June 1 to June 30, 2020. The constructs and principles of the theory of planned behavior (TPB) were measured. We selected using a systematic sampling method and collected data by using a structured interviewer-administered questionnaire. Data was analyzed using SPSS version 25.0. The predictors of intention to practice solid waste management were identified using a multivariable linear regression model. A P-value of less than 5% was considered to declare a significant association.

Results

The findings demonstrated that intention to practice solid waste management explained 86% of the variance explained by all predictors. The perceived behavioral control construct had the greatest impact on households’ behavioral intentions to comply with solid waste management practice (β = 0.16; CI (0.14, 0.18), followed by attitude (β = 0.15; CI (0.11, 0.21) and subjective norms (β = 0.12; CI (0.06, 0.17).

Conclusion

Our study also found that intention has a substantial influence on the behavior of solid waste management practices. Therefore, there is a need to enhance service utilization for solid waste management and to improve outdoor solid waste dropping behavior through door-to-door collection services by municipality. Furthermore, further longitudinal research should be done through intervention mapping.

Identifying the Barriers to Sustainable Management of Construction and Demolition Waste in Developed and Developing Countries

The construction industry is a vital part of every nation’s economy. Construction activities influence the social, environmental, and economic aspects of sustainability. There are so many barriers to sustainable construction and demolition waste management (C&DWM). This study aims to identify barriers for effective sustainable C&DWM in developed and developing countries. To achieve the objective, 11 barriers have been selected and identified based on an excessive and comprehensive literature review, and then reviewed by experts. These reviewed barriers were further examined by various experts within different organizations using a questionnaire survey. Ranking of the barriers was carried out using the Relative Importance Index (RI), and the results were statistically analyzed using Statistical Package for Social Sciences (SPSS). Practical solutions were proposed to overcome the identified barriers. The overall ranking of barriers by RI indicates that insufficient attention paid to C&DWM, lack of law enforcement, lack of regulation, and financial constraints represent the four major barriers to sustainable C&DWM in these countries. The findings of this study and the proposed solutions are enablers for decision-makers to develop effective strategies to tackle construction and demolition wastes in sustainable manners.

Considering Consumers’ Green Preferences and Government Subsidies in the Decision Making of the Construction and Demolition Waste Recycling Supply Chain: A Stackelberg Game Approach

Resource utilization of construction and demolition waste (CDW) is regarded to be an important means of achieving the sustainable development of the economy and the environment. However, previous research has not fully considered the green degree of products in the demand function of CDW remanufactured products. This study aimed to clarify how consumers’ green preferences and government subsidies affect decision making in the supply chain. First, a CDW resource utilization supply chain model composed of building materials manufacturers and retailers was constructed using consumer behavior theory. Second, the optimal decision making of members under conditions of decentralized and centralized decision making was analyzed using the Stackelberg game solution. Finally, the validity of the model and conclusions were verified by numerical simulation. The main conclusions are as follows. Government subsidies have a different impact on the pricing of new building materials products and CDW remanufactured products. Under decentralized decision making, the optimal profit of the CDW resource utilization supply chain with government subsidies is higher. However, under centralized decision making, the optimal profit is also related to consumers’ green preferences. According to consumers’ green preferences, choosing different decision-making models can not only improve the total profit of the CDW resource utilization supply chain, but also improve the reuse rate of CDW.

Towards zero waste in pharmacy: Challenges and opportunities in Singapore

Background

In line with zero-waste movement, there is a need for pharmacies to start reducing waste. There is no systematic waste minimization efforts by local pharmacies or studies to evaluate their effectiveness.

Aim

Assess behavioral change factors towards waste minimization at National Cancer Centre Singapore and evaluate effectiveness of recycling effort and patient education campaign.

Methods

Preliminary surveys were carried out among pharmacy staff, patients/caregivers to assess behavioral change factors. Recycling rate of staff and plastic bag consumption levels of patients/caregivers were measured.

Results

46 staff members and 335 patients/caregivers were surveyed. Both populations were optimistic about the suggested green initiatives, 82.6% of staff members viewed recycling as a potential solution to reduce waste and 67.6% of patients and caregivers demonstrated willingness to participate in a Bring Your Own Bag (BYOB) campaign. Recycling efforts improved recycling rates by 53.4% while BYOB campaign resulted in no notable decrease in plastic bag consumption levels.

Conclusion

This study revealed the need for improvements in current waste management practices in local pharmacies, and demonstrated the effectiveness of implementing a recycling effort. BYOB campaign was not shown to be effective. Follow-up studies should be carried out to capture long-term sustainability data. Future efforts should include studies at other non-specialized local pharmacies.

Predictors of waste sorting and recycling behavioural intention among youths: Evidence from Shenzhen, China and Turku, Finland

Waste sorting and recycling (WSAR) is a crucial issue for sustainable waste management. Growing up with new values, the younger generation has the responsibility to lead the society towards a sustainable future. The successful implementation of WSAR requires an in-depth understanding of the attitudes and obstacles of the youth participation. This study seeks to explore and compare the influencing factors of youth engagement in WSAR in Shenzhen, China and Turku, Finland by drawing on the theory of planned behaviour. Quantitative data was collected from 170 youth citizens in Shenzhen and 179 in Turku. Structural equation modelling results suggest that there is a clear consistency between the youth's intention and behaviour in both cities. Two reverse pyramids were constructed to prioritize the influencing factors based on their importance in the structural models. Subjective norms, knowledge and perceived behavioural control are key influencing factors in Shenzhen group while in Turku' s setting, compatibility acts as a top determinant whereas, subjective norms have the least influencing power. Results from Turku also reveal that lower compatibility does not necessarily hinder youth participation in WSAR practice. Several suggestions and implications on boosting youth participation in WSAR are drawn, based on these findings.

Megaproject Environmentally Responsible Behavior in China: A Test of the Theory of Planned Behavior

Construction megaprojects play a significant role in today’s infrastructure provision in terms of sustainable development, and their increasing proliferation worldwide means the environmentally responsible behavior (ERB) of those involved are becoming of vital importance. This study investigates how ERB can be best supported in megaprojects by first identifying the motivational factors that are involved based on the theory of planned behavior (TPB), followed by a survey of 188 managers involved in China megaprojects to test the TPB model using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results strongly support the TPB model’s predictive ability, with subjective norms being the strongest predictors, followed by attitudes and perceived behavioral control. These findings provide support for decision makers in helping to cultivate and improve the level of megaproject ERB in China and many other such countries that are similarly involved.

Strategies for Enhancing Construction Waste Recycling: A Usability Analysis

Prior works have suggested various strategies to increase construction waste recycling (CWR) rates. However, choosing the strategies is challenging without a lateral comparison. Therefore, this study aims to compare the usability of various strategies that target the enhancement of CWR implementation. To achieve this purpose, thirteen CWR enhancement strategies were identified from a systematic literature review. Then, questionnaire survey data were collected from 106 construction project managers. The collected data were analyzed via mean score ranking, normalization, overlap analysis, agreement analysis, and factor analysis. Additionally, the data were analyzed using a proposed formula for computing usability indexes using the cost, easiness, and effectiveness values. The results show that three strategies have high usability indexes: organize temporary bins in each construction zone, identify construction activities that produce recyclable materials, and enhance company policies related to CWR. These strategies with high usability indexes are consistent with the overlapping cheap, effective, and easy strategies. This study provides researchers and practitioners with optimal strategies for enhancing CWR implementation. Effective CWR enhancement strategies can improve CWR rates in construction projects. Future researchers can also adopt this study’s approach in computing usability indexes through questionnaire surveys.

How can residents be motivated to participate in waste recycling? An analysis based on two survey experiments in China

Waste recycling constitutes an important part of sustainable municipal eco-management, but the chronic and enduring problem in China is how to motivate residents to participate. Although previous research has found that persuasive incentives can exert a powerful influence on people's pro-environmental behavior, little work placed much emphasis on the effect of various incentives and make a comparison. The moderating role of social norms in indigenous scene is also ignored. The present research attempts to tackle this issue to explore theoretically the black box of China's policy implementation. We conducted two survey experiments online in China from February 28 to April 25, 2021. The results in experiment 1 show that four incentives significantly affect respondents' disposition toward recycling behavior, of which monetary incentive is the most effective strategy and the order of the rest incentives is environmental framing incentive, institutional incentive and moral incentive according to the effect calculated by the model. Furthermore, experiment 2 finds that social norms positively moderate the nexus between incentives and recycling behavior, and descriptive norms play a more significant role than injunctive norms. Finally, implications for public policy and limitations are discussed.

Effect of energy management and waste management on schedule performance: role of technological complexity and project size

Schedule overrun is one of the greatest hindrances to construction project performance, thereby making schedule management an integral part of construction project management. The aim of this study is to examine how the effect of sustainable energy management (SEM) and sustainable waste management (SWM) on schedule performance (SP) is mediated by technological complexity (TC) and moderated by project size (PS). Data were obtained by means of a questionnaire survey of 168 completed construction projects in Nigeria. The partial least squares structural equation modelling (PLS-SEM) technique was adopted in analysing the collected data. The results show that TC partially mediates the relationship between SWM and SP, while TC fully mediates the relationship between SEM and SP. Also, the findings of the study indicate that the negative effect of SWM on SP will be greater with large PS. This study contributes to previous studies in the area of schedule management, by providing empirical proof to explain the means through which SWM and SEM could lead to SP through TC, and how this would vary depending on PS. The study proffers ways for contractors to improve the SP of their projects considering PS and TC.

Evaluating the capability of municipal solid waste separation in China based on AHP-EWM and BP neural network

With the increase in municipal solid waste (MSW), most cities face solid waste management issues. In this study, the analytic hierarchy process (AHP) and artificial neural network (ANN) models were improved to assess the MSW separation capability based on 18 selected indicators of solid waste separation in 15 cities in China. The entropy weight method (EWM) was used in AHP to optimize and determine the indicators and then evaluate their weights, which showed that the general public budget expenditure had the highest weight (0.5239). This implied that the MSW separation capability could be mainly influenced by government financial support. ANN based on scan optimization and machine learning methods were established (R² = 0.9992) to predict the missing indicators. The mapping relationship between MSW separation indicators and capabilities was also significantly improved from R² = 0.5317 to R² = 0.9993, thereby increasing the prediction accuracy of MSW separation capabilities to 95.15%. Thus, this research provides a new avenue for MSW separation and establishes a combined model to predict the separation capability in practical applications.

Recycling habits and environmental responses to fast-fashion consumption: Enhancing the theory of planned behavior to predict Generation Y consumers' purchase decisions

Fast-fashion industry is characterized by short product life-cycles, high volatility, affordable prices, and consumers' high impulse purchase decisions, which result in massive levels of waste and greenhouse gas emissions. In this context, Generation Y, the largest consumer of fast-fashion products, is believed to make this situation even worse, since their attitudes/intentions do not usually translate into actual pro-environmental behavior and they are still reluctant to dispose of their clothes through sustainable methods. However, the attitude/intention-behavior gap among Generation Y's fast-fashion consumers remains poorly understood. The present study addresses this need by adopting the Theory of Planned Behavior to examine the link between attitudes, intentions, and behavior, taking into account consumers' participation in recycling as a moderating variable. Results from a two-steps cluster analysis and a multiple moderated mediation analysis on a sample of 943 Italian Generation Y's consumers of fast-fashion products show that the attitude/intention-behavior gap seems not to exist in the Generation Y's context, since the favorable appraisal of sustainable products and consumption actually leads to socially-responsible consumer behavior. However, participation in recycling is found to reinforce the intention-behavior link only for individuals with high environmental attitudes. The present paper contributes to both fashion consumption and solid waste management literature by drawing connections between socially-responsible consumer behavior and recycling habits within the Generation Y's cohort, thus deepening comprehension of this rather unexplored context. Moreover, this study reveals policy development areas that allow the fashion industry to meet customers' needs in new ways.

Has China’s Construction Waste Change Been Decoupled from Economic Growth?

Construction waste management is crucial to the sustainable development of the construction industry and environmental management, and China has the highest construction waste emission in the world, making it typical and representative globally. In this paper, we conducted an empirical study on the relationship between the change in construction waste and economic growth at the provincial level in China from 2009 to 2018 based on a decoupling model and spatial analysis methods, and we reached the findings as follows. (1) Most provinces in China are still in the stage of continuous growth of construction waste emissions, and about 30% have reached the peak (inverted U-shaped), prominently characterized by inter-provincial spatial heterogeneity and agglomeration. (2) The decoupling types between inter-provincial construction waste and construction economic growth in China are dominated by weak decoupling, expansive coupling, and recessive decoupling, and they are changing in general with positive signs but in a more diversified and complex trend. (3) Based on the analysis results, this paper classifies China into three types of policy zones, namely transformation, adjustment, and stabilization, and proposes differentiated and targeted recommendations to provide an important decision basis for the design of construction waste management policies in China and similar countries and to help achieve a “zero waste society” in early global development.

What Influences Consumers to Recycle Solid Waste? An Application of the Extended Theory of Planned Behavior in the Kingdom of Saudi Arabia

This extant study attempts to present a comprehensive predictive model for solid waste recycling behavior. Solid waste is a major environmental concern globally. Particularly, the kingdom of Saudi Arabia (KSA), being the larger gulf country in the Middle East is a major contributor to solid waste. Consequently, this study was carried out to identify the motivational factors that consumers consider important for recycling their household waste. We extended the theory of planned behavior (TBP) and utilized actual behavioral variables such as resell, reuse, and donation. A structured questionnaire was carried out with 365 purposively selected respondents in the KSA. Among several other noteworthy findings consistent with previous studies, we found that reselling was the most significant factor of recycling behavior followed by donation. Further, the multi-group analysis (MGA) results reveal significant group differences in gender and age variables; the significance test indicates that the male group has much better pro-environmental behavior than the female group. In terms of age, our results showed that recycling intention and reselling behavior passed a significant test in the elderly group when compared to a younger group. This study has unique contributions and findings leading to practical implications for government authorities, businesses, and non-governmental organizations. The findings will particularly aid in increasing the recycling intention and behavior among household consumers. This research will guide in making laws and policies that can help to embrace the green challenges and boost recycling activities for a sustainable environment.

Influence of construction company size on the determining factors for construction and demolition waste management

Due to the relevance of construction and demolition waste (CDW) generation for circular economy and reduction of environmental impacts, it is important to evaluate the factors leading to constraints regarding waste. Previous researchers have assessed construction company attitudes and behaviors toward CDW management, but factors such as the presence of environmental technicians, registration of the CDW generated, commitment to the legal framework, the subcontracting regime, and construction works' oversight were rarely addressed in terms of the differences existing within the construction sector. Thus, the objective of this research is to evaluate the relationship of these factors with construction company size. A questionnaire was sent to Portuguese construction companies, and 652 responded. The sample was divided into three groups: micro, small, and medium/large companies. Statistical data treatment was carried out to assess whether there were statistically significant differences in the mentioned factors between groups. The main conclusions highlight: the prevalence of environmental technicians working in larger companies; the registration on waste platforms being only performed consistently by medium/large companies; a considerable proportion of micro and small companies having knowledge gaps about the practices adopted; the responsibility for CDW management within the subcontracting regime being mainly from subcontractors; and the presence of a gap regarding onsite construction works oversight. These differences lead to the need to reevaluate the strategies for CDW management and adapt the strategies to the specific conditions of the construction sector, including the size of construction companies.

Decision-making interaction among stakeholders regarding construction and demolition waste recycling under different power structures

The market power and competition scenario of recycling enterprises and landfills may change in the future due to the environmental pressure caused by landfills and the environmental potential of construction and demolition waste (C&DW) recycling. In this context, how these changes will affect the economic performance of enterprises and the environmental performance of the whole society remains unclear, along with how the willingness to pay and the environmental awareness of contractors will affect the pricing decisions of recycling enterprises and landfills. This study investigates the charging and recycling problem under different power structures in the reverse supply chain of C&DW, which is composed of waste generators (construction contractors) and two disposers (recycling enterprises and landfills). The interactive decisions of three stakeholders are discussed and the optimal charge fee, profit, and recycling ratio are obtained. Results indicate the following (i) The environmental preference of contractors directly increases the charge fee of recycling enterprises, and indirectly increases the charge fee of landfills. (ii) An increase in contractors' environmental preference will reduce the recycling ratio of C&DW and increase landfill and illegal dumping ratios. (iii) From the perspective of environmental benefits, illegal dumping and recycling ratios experience the worst scenario in the Recycling-Stackelberg game model and the best scenario in Nash game model because recycling enterprises take advantage of their dominant market position and set higher charges than those that contractors can afford. This theoretical study bridges the research gap on the effects of the market power on the environmental and economic performance of stakeholders in the field of C&DW management. The findings also help policy makers understand the behavior of stakeholders under different power structures to formulate the most effective intervention strategies.

A text mining-based thematic model for analyzing construction and demolition waste management studies

Over the years, numerous studies have been conducted to investigate construction and demolition waste (CDW) management problems. However, the massive amount of literature brings challenges to scholars because it is difficult and time-consuming to manually identify research emphasis from the literature. Therefore, a method that can informationize literature collection and automatically detect insights from the identified literature is worthy of exploration. This paper attempts to present a comprehensive thematic model by combining Latent Dirichlet Allocation, word2vec, and community detection algorithm on python to detect insights from CDW management literature. Based on the database of Web of Science, 641 articles published between 2000 and 2019 are retrieved and used as the sample for analysis. The comprehensive thematic results reveal a four-domain knowledge map in CDW management research, which covers (1) introducing current situation of CDW management, (2) quantifying CDW generation, (3) assessing CDW and by-products, and (4) facilitating waste diversion. Future research directions in CDW management research have also been discussed. The results prove that the comprehensive thematic model is useful in mining insights from CDW management literature.

Strategies for Effective Waste Reduction and Management of Building Construction Projects in Highly Urbanized Cities—A Case Study of Hong Kong

Hong Kong is a densely populated city with high-rise developments, and as in other metropolitan cities, the amount of waste generated from construction projects in the city is increasing annually. The capacity of existing landfills is expected to be saturated by the 2020s. Construction waste management has been implemented for years but the performance is still not satisfactory. The aim of this research paper is to explore and formulate strategies and measures for effective construction waste management and reduction in highly urbanized cities such as Hong Kong. A desktop study on construction waste management practices was carried out for a preliminary understanding of the current situation in Hong Kong. Semistructured interviews and focus group meetings were further conducted to shed light on how to improve construction waste reduction and management in Hong Kong. The main contributions of this research study are the potential short-term, medium-term, and long-term strategies, which are related to the design stage, tender stage, construction stage, and government support. The five major strategies recommended are financial benefits to stakeholders, public policies in facilitating waste sorting, government supports for the green building industry, development of a mature recycling market, and education and research in construction waste minimization and management.

GHG Emissions Assessment of Civil Construction Waste Disposal and Transportation Process in the Eastern Amazon

The urbanization process represented by an increased supply of housing and transport infrastructure has taken place at an accelerated rate in several regions of Brazil, especially in the metropolitan areas of the Brazilian Amazon. Despite the existence of environmental policies that guide the proper disposal of civil construction waste (CCW) in Brazil, the impacts of these policies are still negligible, pointing to the need to establish other metrics such as the measurement of greenhouse gas (GHG) emissions in CO2eq associated with civil construction waste. This work aims to evaluate, in the second-largest city in the Brazilian Amazon, the environmental impact generated by the transportation of CCW to disposal sites, having as indicators the volume of this waste and the CO2 emissions produced during a whole year. A literature review on life cycle carbon emissions assessment in building construction and CO2 emissions in transportation are provided to establish the background of the research methodology. Data collection was carried out by searching large generators of construction waste, the companies responsible for transporting construction waste, and the types of vehicles used. Calculation of GHG emissions from CCW transportation was based on the method described in the 2006 IPCC Guidelines. The study identified a volume of waste of around 1244 m3/month, with a generation of 40,440 kgCO2/year, only from small and large generators. Besides the damage identified in this study, there is also the dumping of CCW into urban streams in the city which is causing negative impacts on sanitation and drainage systems. The results point to the need to strengthen local policies to mitigate the impacts of the existing CCW to contribute to a more sustainable city.

Incentives for Plastic Recycling: How to Engage Citizens in Active Collection. Empirical Evidence from Spain

The recycling target for plastics is expected to increase Europe-wide from 22.5% to 55% by 2025, hence the relevance of incentive schemes and the need to reach conclusions about how to encourage families to recycle more. Following this objective, a pilot project was implemented and a virtual reward token called RECICLOS created to encourage recycling among families, using incentives and awards to improve recycling behaviour and a webapp prototype to register the recycled plastic. By the end of the 6-week pilot project, 1053 families were registered on the scheme, representing 10% of the targeted population in the pilot area of the county of Pla de l’Estany, Catalonia, Spain. The novelties were the introduction of a token, the gamification of incentives through raffles and lotteries, webapp-based direct communication with citizens, and feedback after collecting and registering the recycled material. The multidimensional aspects of recycling activities, their strong relation with human behavioural patterns, and the high demand for communication and interaction mean that mobile technologies find significant application in this field. The results show that people can be influenced and their recycling habits changed by means of varied, effective, and innovative incentive schemes.

Determinants Affecting Purchase Willingness of Contractors towards Construction and Demolition Waste Recycling Products: An Empirical Study in Shenzhen, China

Waste recycling is a critical method to effectively address environmental issues raised by construction and demolition waste (C&DW). As highlighted in previous studies, the contractor is considered the primary purchaser for recycled C&DW products. However, there is a limited understanding of the factors affecting the contractor’s purchase willingness towards C&DW recycling products. This study investigated these key drivers using the Exploratory Sequential Mixed Approach. Firstly, a hypothetical model was developed based on the theory of planned behavior (TPB). Secondly, a questionnaire survey was then employed in data collection. Thirdly, structural equation modeling (SEM) was adopted for data analysis. It is revealed that multiple factors directly affect the contractor’s purchase willingness towards C&DW recycling products. These factors include government measures, the contractor’s attitude, perceived behavioral control, perceived consumer effectiveness, and subjective norms. Besides, recycling product information indirectly affects the contractor’s purchase willingness. Based on the findings, the study provides strategies for the government, contractors, recycling enterprises, and public buyers to increase C&DW recycling products’ purchase willingness. Findings derived from the empirical study can be used as a theoretical reference for government departments to develop related promotion policies. Moreover, the suggestions provided are helpful to guide recycling enterprises to promote their products.

Consumer Intention to Participate in E-Waste Collection Programs: A Study of Smartphone Waste in Indonesia

Indonesia is a developing country with a low-level e-waste management system based on a limited number of informal initiatives. E-waste requires proper management procedures, which involve the design of a reverse logistics management network. Consumers play a critical role in such a network, because the network runs when they willingly participate as suppliers of waste. This paper applies the Theory of Planned Behavior framework and extends it using Reverse Logistics drivers, the Value Belief Norm Theory, and facility accessibility to explain consumer intention to participate in e-waste collection programs. A survey was conducted on smartphone users in Indonesia, with a total of 324 valid questionnaires. The results showed that government drivers, facility accessibility, and personal attitudes significantly influence consumer intentions. Environmental concern has a positive influence on consumer intentions through the variables of the Theory of Planned Behavior and perceived behavioral control through government drivers. This study shows the need for integration, because the variables reinforce each other. However, neither economic drivers nor subjective norms significantly influence consumer intentions. This finding distinguishes Indonesia from other countries, especially developed countries, in that e-waste collection programs have not become part of the culture in Indonesia. For this reason, Indonesia needs regulations, as the most influential variable, to regulate the implementation of such a program.

Multi-stage network-based two-type cost minimization for the reverse logistics management of inert construction waste

The growing concerns for achieving sustainability has gained much attention from waste management experts with particular focus on reverse logistics, as it supports concepts like circular economy, material recovery, and improved environmental performances. This paper describes a multi-stage network-based model to minimize the overall cost for the reverse logistics management of inert construction waste across its entire life cycle. This model takes a unique two-type costing approach to overcome the ambiguities and deficiencies existing in previous models. Type-I cost refers to the facility-based costing (FBC) and Type-II cost refers to non-facility based costing (NFBC). The mixed-integer linear programming technique is applied using the LINGO software. A case study of construction waste management in Hong Kong is conducted to validate the developed model, which includes waste generation point as the starting node, public fill reception facility and recycling facility as an intermediate node, and landfill as an ending node. The result shows about 24% reduction in the total cost compared to the base case. Furthermore, to evaluate the impact of uncertainties on the cost parameters, a detailed scenario based sensitivity analysis is conducted. The optimal result shows that the larger portion of total cost come from the NFBC component. Therefore, NFBC is critical in defining the overall reverse logistics network and thus, should be given more emphasis in the design of an effective construction waste management system.

Implementing on-site construction waste recycling in Hong Kong: Barriers and facilitators

Construction and demolition (C&D) waste recycling constitutes an indispensable component in the overall waste management strategy. Unlike the traditional recycling approaches whereby C&D waste is transported to off-site facilities for treatment, construction managers are actively exploring the possibility of on-site recycling where C&D waste is treated directly at source. This study reports the barriers and facilitators of implementing on-site C&D waste recycling by contextualizing it in Hong Kong. It does so by adopting a mixed-method approach combining case study, site visits, and interviews. It is discovered that the barriers include (1) site space constraints, (2) narrow window of opportunity to trade recycled products, (3) vulnerable business case, (4) lack of support from off-site recycling, and (5) lack of government policy support. A series of facilitating measures are also proposed, including (1) developing customized on-site recycling equipment, (2) establishing a demand-supply information-sharing platform, (3) developing more thriving off-site recycling, and (4) providing more government support. This study probes into the real-life on- and off-site waste recycling practices in Hong Kong's prominent C&D management system. It can also provide useful references for others in developing their own C&D waste recycling strategies by rationally deploying on- and off-site recycling.

E-waste recycling intention paradigm of small and medium electronics store managers in Bangladesh: An S-O-R perspective

Each year Bangladesh produces around 400,000 metric tonnes of e-waste. E-waste accumulation is expected to increase by 20% annually. In order to facilitate e-waste recycling, it is crucial to identify the factors. In this study, building on the stimulus-organism-response framework, we develop a research model to explore the effect of information publicity, ascription of responsibility and convenience of recycling on the recycling attitude, subjective norm, personal norm and perceived behaviour control which lead to recycling intention. Data were gathered from 127 small and medium electronics store managers. The structural equation modelling technique was used to test the paths. The result suggests a significant influence of the element of stimulus (S) on the element of organism (O). The relationship between the element of organism (O) and the element of response (R) is partial. This paper contributes to the body of work dedicated to helping us better understand the recycling behaviour from the stimulus-organism-response perspective. From the viewpoint of practice, this research sheds light on some of the challenges that the implementer might face when making strategy and policy for e-waste management in Bangladesh.

Using Recycled Construction and Demolition Waste Products: A Review of Stakeholders’ Perceptions, Decisions, and Motivations

While the increasing rate of urbanisation is a critical concern for socio-environmental reasons, this also leads to more extraction of natural raw materials and the generation of significant quantities of construction and demolition (C&D) waste. Although the use of recycled C&D waste products is technically feasible and regulated, and positive application examples are evident, it is still unclear how to engage key stakeholders to leverage this opportunity in construction projects. Previous research has shown that there is some level of resistance to the reuse of recycled C&D waste products in construction projects. This highlights a critical need to identify the roles of key stakeholders and the barriers they face when using recycled C&D materials. This paper therefore investigates the type of stakeholders influencing the use of recycled C&D waste products and the main factors affecting stakeholders’ decisions to use recycled C&D waste products through a systematic literature review. The authors present an emergent enablers and barriers for recycled C&D waste products model and provide commentary on how stakeholders’ perceptions, decision and behaviour influence the use of recycled C&D waste products. The authors also contribute to the body of knowledge with insights into the factors that various stakeholders believe influence the market for recycled C&D waste products and provides a reference point for authorities to consider these behavioural insights for policy reform.

Multi-agent evolutionary game in the recycling utilization of construction waste

The recycling utilization of construction waste (CW) is of great importance to reduce waste discharge and protect natural resources. This study investigated the evolutionary decision making process and stable strategies among three stakeholders, including the government agency (GA), waste recycler (WR) and waste producer (WP), involved in CW recycling industry based on the game theory. The main factors that affected the strategies of the stakeholders were analyzed and the tripartite evolutionary game model is provided. The evolutionary stability strategy and stability conditions were analyzed subsequently. A numerical simulation illustrated the effectiveness of the proposed method, with which the evolutionary decision making process and stable strategies among the three stakeholders are simulated. It is shown that the GA plays different roles in different stages of the development of CW recycling industry. In the early stage, the supervision and policies of the GA are critical to improve the proportion of enterprises that implement the recycling strategy. With the mature of the CW recycling industry, it is profitable for enterprises to implement waste recycling, and a high proportion of enterprises choose to implement recycling strategy. Under this circumstance, the GA will gradually decrease their interventions to enterprises, and finally evolve into no supervision. Besides, it also concludes that low penalties and subsidies are not conducive to the evolution of the optimal strategy among the three participants, and excessive supervision costs will reduce the regulatory willingness of the GA, hindering the enthusiasm of WRs and WPs to implement the recycling strategy.

System dynamic analysis of construction waste recycling industry chain in China

With the acceleration of China's urbanization process, construction activities have led to a substantial increase in construction waste. However, as China's construction waste recycling rate is low, it is difficult to convert construction waste into valuable products for the sustainable development of waste resources. The biggest reason for this is the construction waste industrial chain, which is imperfect and has many problems. In this study, a simulation model is established using system dynamics software Vensim PLE. The analogue simulation shows that (1) China generates a large amount of construction waste every year. If construction waste source reduction measures are implemented, it will inhibit 50% of the waste generated. Upstream enterprises in the industry chain should actively develop waste reduction technology and improve waste reduction management; (2) marginal effect exists in the single waste reduction measure, but the government should implement more portfolio reduction measures to enhance the reduction effect, which is often three times that of the single policy; (3) the middle stream recycling enterprises in the industry chain cannot solely rely on government subsidies to reduce the cost of waste recycling. It is necessary to create synergistic linkages with more responsible entities upstream and downstream of the industry chain, thus creating a new model in construction waste management. (4) Government policies tend to drive the purchasing power of building material market. The government should actively exert its subjective initiative, supervise and provide policies to help the downstream enterprises that supply recycled building materials in the industry chain, and change the rigid understanding of contractors and owners about recycled building materials. The research conclusions can provide theoretical guidance for industry chain-related enterprises and government management departments in policy formulation, so that construction waste is sustainably developed.

Perceived Value Influencing the Household Waste Sorting Behaviors in Rural China

Waste sorting is the cardinal measurement to solve the problem of low efficiency of rural environmental governance and to alleviate environmental pollution by reduction, recycling, and harmlessness in rural areas. However, non-excludable and non-rival features of public goods easily cause a wide free-rider problem, which results in a low frequency of participation in the waste sorting of rural people. Based on the theory of the utility maximization of the rational economic man, this paper investigates survey data of 688 farm households in three cities and three counties of Shaanxi Province to explore the effect of the perceived value on the household waste classification behavior based on cost-benefit analysis. The results show that perceived benefit and perceived cost are important perceived value factors affecting farmers’ participation in waste sorting. Specifically, the spiritual benefit of the perceived benefit has a significantly positive impact on classification behavior, while the time cost, physical cost, and material cost of the perceived cost have a negative impact on waste classification behavior. Further study of the heterogeneity of income impact shows that time cost only has a significant impact on the high-income group of farmers’ classification behavior, while spiritual benefit and learning cost only affect the low-income group of farmers’ waste classification behavior. Material cost has different influence directions on high- and low-income groups. In view of the aforementioned findings, this study highlights corresponding policy implications from the perspective of perceived benefit and perceived cost.

Sorting of suitable areas for disposal of construction and demolition waste using GIS and ELECTRE TRI

Inadequate construction and demolition waste disposal create severe environmental impacts in cities when it occurs in an uncontrolled manner. For waste with the possibility of recycling, the appropriate destination would be recycling plants or landfills. In the investigative process, no studies were found that considered the sorting procedure by compensatory and non-compensatory multi-criteria analysis integrated to the Geographic Information System to choose suitable landfills or recycling plants in cities. This study aims to fill this gap with a structured methodology for mapping suitable sites to receive inert waste from small and medium cities. For this, it was considered the identification of relevant criteria and weights definition by Analytic Hierarchy Process method and after performing a sorting procedure by ArcGIS 10.0 software (compensatory aspect) and ELECTRE TRI method (non-compensatory aspect). And then, an aggregate analysis in order to support the decision-making was also developed. An experimental study was carried out with the application of this methodology in a city of the south western of Parana, Brazil, allowing the analysis of criteria such as land use, soil type and slope, as well as distances to urban area, education and health institutions, roads and highways and hydrography network. We combined these data in a multi-criteria analysis to provide an aptitude mapping to identify suitable landfill areas with 5 km², and sorted as low, medium and high aptitude classes by ArcGIS software and ELECTRE TRI method. With all that, it shows to be efficient, providing relevant practical and theoretical implications to this theme.

Digital Twin and Web-Based Virtual Gaming Technologies for Online Education: A Case of Construction Management and Engineering

Mixed reality is advancing exponentially in some innovative industries, including manufacturing and aerospace. However, advanced applications of these technologies in architecture, engineering, and construction (AEC) businesses remain nascent. While it is in demand, the use of these technologies in developing the AEC digital pedagogy and for improving professional competence have received little attention. This paper presents a set of five novel digital technologies utilising virtual and augmented reality and digital twin, which adds value to the literature by showing their usefulness in the delivery of construction courses. The project involved designing, developing, and implementing a construction augmented reality (AR), including Piling AR (PAR) and a virtual tunnel boring machine (VTBM) module. The PAR is a smartphone module that presents different elements of a building structure, the footing system, and required equipment for footing construction. VTBM is developed as a multiplayer and avatar-included module for experiencing mechanisms of a tunnel boring machine. The novelty of this project is that it developed innovative immersive construction modules, practices of implementing digital pedagogy, and presenting the capacity of virtual technologies for education. This paper is also highly valuable to educators since it shows how a set of simple to complex technologies can be used for teaching various courses from a distance, either in emergencies such as corona virus disease (COVID-19) or as a part of regular teaching. This paper is a step forward to designing future practices full of virtual education appropriate to the new generation of digitally savvy students.

The effect of policy instruments on rural households' solid waste separation behavior and the mediation of perceived value using SEM

Based on expectancy valence theory, people's behavior is affected by their self-perception and the external environment. In rural China, policy instruments as robust external environment factors have a strong effect on waste separation behavior (WSB). The purpose of the paper is to explore the influencing mechanism of policy instruments (infrastructure and information) on perceived value (perceived benefit and perceived cost) and waste separation behaviors. The data were collected from 689 rural households of Shaanxi province in China, and analyzed by using structural equation model (SEM). According to the results, the mediation effect proves that policy instruments not only can affect WSB directly but also can affect it indirectly through the perceived value. Specifically, information and infrastructure influence the perceived benefit positively and the perceived cost negatively, and information and infrastructure have an indirect effect on WSB through the mediation effect of the perceived cost. Second, policy instruments have a stronger effect on rural people's waste separation behavior than perceived value. Specifically, infrastructure has the most important impact on waste separation behavior, followed by information and then perceived cost. Third, the perceived cost is significantly negatively related to WSB, and perceived benefit has a positive effect but is statistically insignificant. It has a practical implication for the government. Providing sufficient infrastructure and launching effective information activities could improve the perceived benefit including biospheric, egoistic, social-altruistic, and reputation; and reduce the perceived cost of time, physical, learning, and money, which could then induce rural households to engage in WSB.