Developing a risk assessment model for circular economy practices in construction project

THESIS TOPIC TÊN ĐỀ TÀI: DEVELOPING A RISK ASSESSMENT MODEL FOR CIRCULAR ECONOMY PRACTICES IN CONSTRUCTION PROJECT.. TASKS AND CONTENTS: Developing a risk model and evaluate the risks o

Introduction

Problem statement

In recent decades, climate and environmental changes have emerged as critical global issues, exacerbated by high population growth and rapid urban development This has led to the depletion of natural resources and a significant rise in environmental degradation and pollution Consequently, resource limitations and environmental challenges have become pressing concerns worldwide, with pollution recognized as a major problem affecting both developing and developed nations.

The Construction Industry (CI) significantly impacts the economy while being a major contributor to resource consumption.

The construction industry is a major consumer of raw materials, utilizing over half of the world's steel and more than 3 billion tons of natural resources annually, which contributes to significant resource depletion and future shortages This sector generates up to 40% of global waste by volume, including construction and demolition waste (CDW) that poses landfill challenges and depletes land and resources The environmental consequences of high consumption and waste generation include air, water, and soil pollution, along with increased CO2 emissions Despite the industry's profound impact on the economy and environment, there is a lack of research on implementing circular economy (CE) practices within construction The circular economy offers a solution to the pressing demand for natural materials and aims to mitigate environmental harm by promoting a sustainable model based on the principles of reduce, reuse, and recycle, contrasting the traditional linear economy of take-make-use-discard.

The circular economy promotes the recycling of materials, maximizing the end-of-life value of components to enhance resource efficiency and prevent waste generation The construction industry, with its various specialized units involved in construction, maintenance, repair, and demolition, faces significant risks that can lead to time and cost overruns or project failures Effective risk management is essential, involving the identification and prioritization of risks alongside the development of contingency plans However, circular construction, being innovative and still in its infancy, is particularly susceptible to challenges such as supply chain issues, economic uncertainty, and the quality of recycled materials Stakeholders in the construction industry are keen to adopt circular economy practices, yet there is a lack of research on risk management in this context In Vietnam, where the implementation of circular economy principles is still developing, it is crucial to conduct risk analyses to raise awareness among stakeholders about the potential hazards that could impede circular construction projects Developing countries, including Vietnam, face heightened vulnerabilities due to limited technological capabilities and a shortage of skilled labor, making it imperative to understand the serious risks associated with circular economy practices in construction.

Therefore, the research article below will help people better understand the operation of the circular economy in the construction industry.

Research objectives

The objective of this research is to create a robust Risk Assessment Model tailored for Circular Economy Practices in construction projects This model will enable stakeholders—such as investors, contractors, consultants, and suppliers—to effectively identify, analyze, and evaluate various risks associated with implementing Circular Economy Practices, encompassing factors related to government/political, technical, economic/financial, market, social, organizational, and logistics.

The research is structured into several key sections: Part 2 offers a literature review on circular economy risk assessment in the construction industry, while Part 3 details the data collection methods and proposed analytical techniques Part 4 presents an analysis of the main findings and engages in discussion, followed by Part 5, which utilizes the FSE method for further analysis of the results Finally, Parts 6 and 7 provide a discussion and summary of the study's primary conclusions and limitations.

The Fuzzy Synthetic Evaluation (FSE) method is widely used in scientific research due to its ability to effectively handle complex evaluation problems with many criteria and

Fuzzy Set Evaluation (FSE) is essential for managing incomplete and ambiguous information due to its ability to handle uncertainty effectively It integrates multiple criteria seamlessly, making it user-friendly and applicable across various contexts Additionally, FSE allows for clear interpretation of results and demonstrates high adaptability, catering to diverse needs and situations.

Research scope

This research aims to create a versatile risk assessment model applicable to various construction projects, emphasizing Circular Economy Practices Key practices include the use of recycled materials, designing for dismantling and reuse, and enhancing building longevity The study will prioritize evaluating the risks linked to the implementation of these practices rather than exploring the technical details of each method.

Limit of study: Survey participants and construction projects are all located in Vietnam, especially in the southern provinces of Vietnam.

Research summary

Time: The study will be implemented from January 2024 to May 2024

+ Research object: Challenges of applying Circular Economy Practices in construction projects

+ Survey subjects: Investors, Construction Contractors, Consulting units, design units, people knowledgeable about Circular Economy Practices

+ Project type: Civil construction project, hotel, resort

Literature review

Definition of circular economy in construction industry

The Circular Economy (CE) is gaining traction in both academia and industry as a sustainable solution that enhances resource efficiency across a product's lifecycle, including production, supply chains, and consumption By focusing on reduction, reuse, recycling, and resource recovery, CE aims to minimize waste and promote sustainability on both macro and micro levels, leading to economic prosperity, environmental stability, and social equity A recent study on CE principles in waste management underscores its significance for developing countries like Vietnam, highlighting the necessity of regulations for effective waste and environmental management systems to foster waste reduction The research also provides legislative recommendations to achieve a "no waste" CE, particularly within the construction industry.

Incorporating Circular Economy (CE) principles throughout the building process is essential for reducing waste and enhancing resource efficiency Circular construction, as depicted in Figure 2, involves planning, designing, building, maintaining, operating, and demolishing infrastructure in accordance with regenerative closed-loop CE principles By integrating CE practices during the design phase and performing life cycle analyses, construction projects can achieve material reuse, decrease reliance on virgin resources, and lessen their environmental impact.

Figure 2.1 circular economy in construction industry [13]

Characteristics of circular economy practices in the construction industry

Recent research has highlighted the integration of Circular Economy (CE) principles within the construction industry, identifying six crucial areas for further exploration These areas include material reuse, life cycle analysis, and the development of sustainable practices that promote resource efficiency and waste reduction in construction processes.

The implementation of Circular Economy (CE) practices in construction faces several challenges, including the selection of sustainable materials, the use of prefabricated elements, and designing for disassembly Key factors for a successful transition to CE involve establishing recovery schemes, ensuring quality specifications for circular materials, and training demolition companies Additionally, effective risk management is essential, as it involves the proactive identification, assessment, and mitigation of risks that could disrupt project activities, ultimately supporting the successful integration of CE practices in the construction industry.

7 outcomes It's a collaborative effort involving the entire organization and its stakeholders

Circular Economy (CE) principles into the construction industry

The risk management process defined in ISO 31000:2018 begins with establishing context, goals, and criteria for effective risk management, followed by a crucial risk assessment phase where potential risks are identified and evaluated The final step involves developing preventive measures to mitigate these risks, while ongoing activities such as monitoring, review, and stakeholder communication are essential throughout the process This research adopts a novel approach that combines SPSS for data analysis and Fuzzy Synthetic Evaluation for risk prioritization, providing a fresh perspective on risk assessment in construction projects While previous studies on Circular Economy (CE) have focused mainly on theoretical frameworks, there is a growing interest among stakeholders in practical CE implementation, which introduces new risks that necessitate thorough risk assessments for successful transitions The World Health Organization has highlighted risks related to material reuse and recycling, particularly concerning hazardous materials, while another study utilizing the DEMATEL technique identified financial risks as the primary concern in circular supply chains Developing countries, such as Vietnam, face heightened risks in CE adoption due to socioeconomic challenges, with studies indicating that project payment delays and funding issues are among the top risks in the construction sector, alongside safety practices and construction accidents Proposed mitigation strategies include enhanced stakeholder coordination, rigorous project supervision, and precise project scheduling.

In the Vietnamese construction industry, a study highlighted the importance of diverse stakeholders, including clients, consultants, and contractors, in managing project risks It recommends that contractors form a competent site management team with adequate authority to address risks related to time, quality, and cost effectively Clients should provide clear specifications to prevent unexpected challenges Additionally, strict adherence to health and safety regulations is essential to avoid productivity loss, health issues among workers, and project delays Kamal (2019) introduced a novel methodology for analyzing health and safety risks faced by construction workers, reflecting the industry's increasing emphasis on risk management.

Barrier to adoption of circular in construction industry

A comprehensive review of existing research on the circular economy in the construction sector highlights the significance of sustainable construction projects and green innovation This analysis aims to identify potential barriers to the adoption of circular economy principles in construction initiatives Key terms such as "barriers," "issues," and "sustainable practices" must be thoroughly assessed to understand the challenges faced in implementing these strategies effectively.

Despite existing research on circular economy practices in construction projects, many studies overlook the interrelationships between barriers, primarily concentrating on identifying common obstacles to implementing these practices in the industry.

Previous research primarily focused on survey data and literature reviews, often lacking comprehensive analysis of the interrelationships between barriers There is a notable deficiency in examining both direct and indirect connections among various obstacles from the perspectives of diverse stakeholders This study seeks to address these gaps in the current literature.

The authors identified and selected key barriers to implementing a circular economy within the construction industry, integrating insights from prior research The following tables present the sources and risk factors identified in previous studies related to the circular economy in the construction sector.

Table 2.1 Characteristics of previous study

Articles Theme Types of study

Risk assessment of circular economy practices in construction industry of Pakistan

Masoud Norouzi Circular economy in the building and construction sector: A scientific evolution analysis [12]

Circular economy in the construction industry: A review of decision support tools based on Information &

Circular Economy in the Construction Industry: A Step towards Sustainable

Barriers to Implementing the Circular Economy in the

Assessing green innovation practices in construction firms: a developing-country perspective

Understanding the key risks in circular construction projects: from systematic review to conceptual framework [20]

Ibrahim Yahaya Wuni Developing a multidimensional risk assessment model for sustainable construction projects

Admitting risks towards circular economy practices and strategies:

An empirical test from supply chain perspective [22]

A fuzzy synthetic evaluation approach to assess the risks associated with municipal waste management: Implications for sustainability [43]

Table 2.2 Characteristics of previous study

1 Lack of awareness for circular construction practices

The lack of knowledge and understanding of CE practices in construction industry

2 Lack of specifications and codes for circular construction

Specification and Building codes unavailability for standardized circular construction

3 Lack of political support and incentives to circular economy

Lack of encouragement and monetary support from policy makers to innovative and sustainable practices

11 practices discourages the stakeholders to shift to innovative practices such as circular construction

4 Considering carefully whether components can be recycled, reused or decomposed

The importance of designing, selecting and managing components with their ultimate life in mind By prioritizing recycling, reuse and composability, we can contribute to a more sustainable future

5 Adopting new or improving existing management systems to implement environment-friendly policies and practices

By adopting a systematic approach, organizations can achieve environmental sustainability and gain a competitive advantage in the marketplace

6 Design changes Design changes refer to modifications made during the design phase of construction projects that promote circular economy (CE) principles

These changes aim to reduce waste, maximize resource efficiency and extend the life of buildings and infrastructure

7 Poor selection of construction techniques in sustainable construction

The selection of construction methods significantly affects a project's sustainability objectives Sustainable construction focuses on reducing environmental impacts across the entire building life cycle, starting from material extraction to the final stages of construction.

8 Lack of coordination strategies managing uncertainties of CE businesses

This description addresses a critical flaw in how Circular Economy (CE) businesses handle the inherent uncertainties associated with their operations

9 Stakeholders' inexperience to circular construction

Inexperienced stakeholders of sustainable and circular construction as they are novel concept

10 Poor leadership and management towards

Ineffective leadership and management practices hinder the successful implementation of Circular Economy (CE) principles in the Supply Chain (SC).

Research gap

The existing literature fails to address risk management and assessment model standards for circular economy activities within the construction industry, particularly in Vietnam, which is in the nascent stages of adopting circular economy principles Conducting risk analysis is crucial to enhance awareness among stakeholders about the significant risks that impede circular construction initiatives Developing countries, including Vietnam, face heightened vulnerability to disruptions and risks due to limited technological capabilities, a shortage of skilled labor, and increased economic costs associated with construction projects Moreover, there is a scarcity of research evaluating the impact of risk factors on the implementation of circular economy practices across various contexts, especially when contrasting traditional resource-intensive models with the regenerative and restorative systems of the circular economy.

Research on the 3R concept (reduce, reuse, recycle) is essential to enhance the understanding and implementation of circular economy practices in the construction industry, particularly in developing countries like Vietnam Addressing existing gaps in knowledge will promote the effective adoption of advanced circular economy strategies in construction projects, ultimately leading to more sustainable practices within the sector.

Research methods

Questionnaire design

This study focuses on evaluating the risks associated with circular economy practices in construction projects and creating a measurement model to quantify circular economy standards in Vietnam's construction sector To meet these research goals, a comprehensive three-part questionnaire was developed.

 Part 1: Introduces research goals and objectives, information encryption, commitment to confidentiality, and explanation of research construct

 Part 2: Candidates are asked to evaluate the influence of the risk factors in circular economy practices in the Construction project with a 5-point Likert (1 = "not low", 5

 Part 3: This part is to collect the information of participants

Business sizes vary significantly in today's construction industry(for example: small

According to current Vietnamese regulations, companies are categorized by size: small (10-100 employees), medium (100-200 employees), and large (over 200 employees) It is essential to evaluate the relevance and applicability of the questionnaire for construction firms of varying sizes Additionally, selecting an appropriate sample size in qualitative research is a significant topic of philosophical discussion and practical uncertainty Sim notes that such study samples are typically purposeful and small, often comprising 2-10 participants For this study, interviews were conducted with ten experts, with two experts from each business type, including investors, project management consultants, constructors, technical consultants, and design consultants All participants have over five years of experience, possess postgraduate degrees, hold management or team leader positions, and have a strong understanding of circular economy principles.

This study explores 16 economic practices in construction projects, inviting experts to evaluate a preliminary questionnaire Each expert provided insights on the questionnaire's characteristics, leading to a consensus on its final version for data collection Given the limited survey duration and a low response rate, a sample size of 120-140 participants is deemed suitable based on previous research.

This study determined an appropriate survey sample size of 120-140 participants, based on previous research indicating that the sample size should be five times the number of observed variables Over 130 professionals from the construction industry, including engineers, architects, project commanders, chief supervisors, design leaders, quantity surveyors, quality assurance/quality control personnel, and site managers with 1-20 years of experience in circular economy activities, were interviewed for preliminary testing of the questionnaire Experts provided valuable feedback on the questionnaire's characteristics, which was then refined for data collection The final survey encompassed seven major factor groups and 29 identified risks, with data gathered through both Google Forms and paper surveys.

Data collection will involve distributing hardcopy questionnaires and e-forms to investors, consultants, contractors, and suppliers E-forms will be shared through Google Forms and email links After data collection, any unsatisfactory responses will be eliminated With the prevalence of numerous social media platforms for information sharing, tools like Messenger (Meta), Zalo, Skype, and Gmail will be utilized to send the e-form links concurrently with the hardcopy versions distributed to colleagues and classmates.

CODE FACTORS IMPACT ON REWORK COST REFERENCE

A Factors related to Governmental/ Political risks

CS1 Lack of effective recycling policies in waste management

Lack of proper vision such as goals, objectives, targets, and indicators in regards to Circular Construction Project

CS3 Lack of sufficient law implementation in circular construction projects

CS4 Lack of political support and incentives to circular economy practices

CS6 Lack of construction industry incentives for

B Factors related to Technical risks

KT3 Lack of specifications for circular construction [16] [22] [28]

KT5 Service life of Circular Material [21] [27]

Limited experience of the consultant about Circular Economy practices in construction project

Limited experience of the contractor about Circular Economy practices in construction project

C Factors related to Economic/financial risks

TC1 Complex Cash Flow due to increase in stakeholders

TC2 Inflation of circular materials [27] [22]

TC3 The higher price difference between recycled products and virgin product

TC4 Profit Uncertainty of Circular Construction [22] [25]

D Factors related to Market risks

TT1 Lack of proper mechanism for take-back [27] [8] [16]

TT2 Time-consuming and labor-intensive remanufacturing procedure

TT3 Shortage in labor skilled in Circular Economy practices in construction project

TT4 Lack of continuous customer interest and attention

E Factors related to Social risks

XH1 Negative Effect of Circular practices on

XH2 Lack of consumer’s knowledge about reused materials

F Factors related to Organizational risks

RR1 Lack of awareness for circular construction practices

RR2 Poor leadership and management towards circular economic in construction project

RR3 Poor-relationships between supply chain partners

G Factors related to Logistics risks

LO1 Improper location selection of depots and containers

LO2 Improper selection of size, type, and capacity of the transport fleet in construction project

Figure 3.2 Relevant risk of Circular economy practices model of Construction projects.

Descriptive analysis

The methods applied to this study include product analysis and statistics (SPSS), Fuzzy Synthetic Evaluation (FSE)

NO OBJECTIVES OF THE STUDY APPLICATION METHOD

1 Collect input data Design survey questionnaire

2 Ranking of methods Calculate the average value

3 Check the reliability of the scale Determine Cronbach's Alpha coefficient using SPSS software

4 Analyze the criteria Cronbach's Alpha coefficient

SPSS STATISTICS 20 would be applied for:

The study utilized Cronbach's Alpha coefficient to analyze data reliability, focusing on the internal consistency of impact assessments and the validity of the questionnaire The results revealed the following Cronbach's alpha values: Governmental/Political risk (0.712), Technical risks (0.735), Economic/Financial risks (0.748), Market risks (0.707), Social risks (0.442), Organizational risks (0.742), and Logistics risks (0.629) Notably, six out of seven values surpassed the minimum threshold of 0.6, indicating acceptable internal consistency and validating the research instrument used in the study.

This article discusses various scoring methods employed in previous research to assess potential risks in construction projects, including criticality, probability rating, impact rating, and risk significance index Each method uses a specific scale, with criticality rated from 1 to 25, while both probability and impact ratings, as well as the risk significance index, are measured on a scale from 1 to 5.

 Criticality (Crj): This score, ranging from 1 to 25, indicates the severity of the potential consequences if a particular risk (j) occurs

 Probability Rating (Prj): This value, on a scale of 1 to 5, reflects the likelihood of risk (j) happening

 Impact Rating (Imj): Scored from 1 to 5, this metric represents the seriousness of the impact if risk (j) materializes

 Risk Significance Index (RSIj): This index combines the probability and impact ratings (ranging from 1 to 5) to provide an overall measure of risk severity for risk (j)

3.2.3 Fuzzy Synthetic Evaluation (FSE) theory

The Fuzzy Set Evaluation (FSE) aims to assess a combined object using diverse criteria within a fuzzy decision-making context Its strength lies in its ability to manage ambiguous and subjective evaluations, often influenced by the decision maker's personal perceptions Consequently, employing FSE to develop an evaluation model in this study is highly suitable.

FSE model theory is built with the following steps:

 Step 1: Build a set of basic variables F = [f1, f2, , fk] In this study, k is the number of design methods for circular economy activities in a construction project, based on the inspection results above k = 29;

 Step 2: Build a set of evaluation options G = G = [g1, g2,…, gi], where i is the number of options In the study using the 5-level Linkert scale, i = 5;

 Step 3: Evaluate the weighting of each design method and the total weight of each criterion group The weight (W) is determined using the GPA

Wi = [w1, w2, w3, wi, , wm] which 0 ≤ msi ≤ 1; i = 1÷ m

The formula is presented as follows:

𝛴𝑀𝑖 , 0 ≤ Mi ≤ 1, ΣMi=1 (1) With Wi = numerical value; Mi = Average value of a specific design variable/method;

To calculate the Fuzzy Evaluation Matrix for each design method, denote it as E = [eij]mxn, where eij indicates the degree of satisfaction of the gj option with respect to each fi method The fuzzy matrix E is structured to reflect these evaluations systematically.

 Step 5: Set up the evaluation matrix for each set of criteria using the weighting vector and the fuzzy evaluation matrix according to the following equation:

F = Wi * Ei (3) with F = evaluation matrix for each criterion; W = weight vector; Ei = Fuzzy evaluation matrix; ‘*’ = Fuzzy synthetic multiplication

From step 3 to step 4, equation (3) can be expressed as follows:

(1) The evaluation matrix for each criterion is standardized, expressed for each specific method is evaluated according to the following equation:

Chapter Summary

Chapter 3 outlines the research methods utilized for data collection and analysis in this master's thesis It begins with the idea generation phase, drawing from previous research articles to develop a survey questionnaire Following a test survey and consultation with an instructor regarding the content, the survey sample size is determined, the questionnaire is refined, and the survey is distributed widely A total of 200 survey forms were sent out, yielding 136 adequate responses across 7 groups and 29 factors The collected data will be analyzed using SPSS Additionally, Chapter 3 introduces Fuzzy Synthetic Evaluation (FSE) as a key component of the research methodology.

23 will be used to "Developing a risk assessment model for circular economy practices in construction project" and evaluate the model

Result analysis

Data collection and analysis

The study employs a non-probability convenience sampling method to gather research data, selected for its flexible participation conditions such as ease of access, time convenience, and geographical proximity, which enhance survey response rates A list of 200 construction professionals, each with a minimum of one year of experience, was compiled through the relationships between students and instructors To ensure the reliability of the research findings, only participants who demonstrated an understanding of circular economy practices were included Additionally, a pilot study was conducted prior to extensive data collection to refine the survey process.

A total of 200 questionnaires were distributed, resulting in 145 responses after three weeks After excluding 9 invalid votes, 136 valid responses were analyzed, yielding an overall response rate of 72.5% This sample size and response rate align closely with findings from previous studies in developing countries.

Characteristics of basic information of survey participants:

- Years of experience in the construction industry:

Figure 4.1 The chart of survey participants' years of experience

A substantial 37% of survey participants have been in the construction industry for only 1 to 3 years, indicating that a significant portion of the workforce is relatively new to this field.

A significant portion of the workforce consists of experienced individuals, with 10% of workers having 10 to 20 years of experience and an additional 4% boasting over 20 years in the construction industry.

A significant portion of the workforce has gained valuable experience in the industry, with 26% of laborers having worked for 3-5 years and 21% for 5-10 years This notable presence of experienced laborers underscores the depth of expertise within the industry.

HOW LONG HAVE YOU BEEN WORKING IN THE CONSTRUCTION

1-3 YEARS 3-5 YEARS 5-10 YEARS 10-20 YEARS >20 YEARS

Experienced professionals in the construction industry bring significant value through their expertise and knowledge They are essential in mentoring and training new workers, which helps ensure high project quality and adherence to industry standards.

Figure 4.2 The chart of survey participants' project types

The majority of survey participants were involved in apartment construction projects: The largest portion of the pie chart, representing 38% of respondents, was in the

"Apartment Building" category This shows that apartments are the most popular type of construction project that many labors participate in

A substantial portion of the workforce is engaged in the construction of hotels, resorts, and complex buildings, with hotel/resort projects representing 21% and complex buildings accounting for 20% of labor involvement This indicates a strong popularity and demand for such construction projects.

Few people participate in factory/factory and school construction projects: The remaining three categories, "Factory/factory construction" and "School construction",

APARTMENT BUILDING HOTEL/RESORT BUILDING COMPLEX BUILDING

FACTORY/WORKSHOP BUILDING SCHOOL BUILDING

27 accounted for a total of 18% of respondents This suggests that these types of construction projects are less popular among survey participants

- Capital sources of the projects:

Figure 4.3 The chart of capital sources of projects

The largest portion of the pie chart, accounting for 60% of funding, falls into the

"private equity" category This shows that private capital is the most popular source of funding for projects

Budget capital constitutes 21% of total capital, highlighting its crucial role in state investment and project financing.

Foreign capital is a relative source of funding: the remaining 16% of capital is from

“Foreign capital”, indicating that foreign investment is less common in these projects

The pie chart illustrates the distribution of capital among various projects, offering crucial insights for project developers, investors, and policymakers By analyzing these patterns, stakeholders can enhance their financial strategies, improve risk management, and identify market opportunities.

CAPITAL SOURCES OF THE PROJECTS

BUDGET CAPITAL PRIVATE CAPITAL FOREIGN CAPITAL

Figure 4.4 The chart of the scale of projects

Large-scale projects are prevalent: The majority of projects fall into the 3 largest scale categories (10-20 billion,100-200 billion and >1000 billion), indicating that large- scale projects are common in this domain

A significant portion of projects are medium-sized: The 20-100 billion, 200-500 billion and 500-1000 billion range represents a notable share of projects, suggesting that medium-sized projects also play a significant role

The pie chart shows the distribution of project sizes in VND The data is classified into five ranges and percentages respectively:

10-20 billion: This range accounts for the largest share of projects, representing only 21% of the total

20-100 billion: This range accounts for a significant portion of projects, representing 11% of the total

100-200 billion: This range accounts for a significant portion of projects, representing 13% of the total

WHAT IS THE SCALE OF THIS PROJECT?

10-20 BILLION 20-100 BILLION 100-200 BILLION200-500 BILLION 500-1000 BILLION >1000 BILLION

200-500 billion: This range accounts for the second largest share of projects, representing 20% of the total

500-1000 billion: This range represents a substantial share of projects, comprising 11% of the total

>1000 billion: This range accounts for the second largest share of projects, representing 20% of the total

The pie chart reveals key insights into the distribution of project scales within the domain, highlighting the significance of large-scale and medium-sized projects as crucial contributors to economic activity and innovation To fully grasp the project landscape, it is essential to consider the specific context and additional data.

- The role of survey participants in the project

Figure 4.5 The chart shows the roles of survey participants in the project

The survey results show the diversity of expertise of the surveyed subjects, in which subjects related to Construction Contracting companies account for the highest proportion

ARE YOU WORKING IN THE COMPANY/IN A PROJECT ROLE?

INVESTOR/PROJECT MANAGEMENT BOARD CONTRACTORS

CONSULTING ON PROJECT MANAGEMENT DESIGN CONSULTANCY

The pie chart illustrates the distribution of stakeholders in the construction sector, highlighting that project supervision engineers and construction supervision engineers constitute the largest group at 41% Design consultancy follows as the second largest group at 26%, while investor/project management boards and consulting on project management represent 14% and 13%, respectively The technical consulting group is the smallest, accounting for just 2% This data underscores the importance of stakeholder roles in assessing circular economy practices within construction projects, emphasizing the need for support in risk assessment.

Figure 4.6 Chart of job positions

The survey results indicate that the Engineer/Architect position is the most prevalent, comprising 45% with 63 out of 136 respondents In contrast, the chief/deputy supervisor role accounts for 13% with 18 individuals Other roles, including head/deputy head of project management board, commander/deputy commander, manager, head, deputy manager, in charge of design, and project director/deputy director, collectively represent the remaining positions.

ARE YOU WORKING IN THE COMPANY/PROJECT WITH YOUR

BUSINESS OWNER/DIRECTOR PROJECT DIRECTOR/DEPUTY DIRECTOR MANAGER, HEAD, DEPUTY MANAGER HEAD/DEPUTY HEAD OF PROJECT MANAGEMENT BOARD COMMANDER/DEPUTY COMMANDER

CHIEF/DEPUTY SUPERVISOR ENGINEER/ARCHITECT

11%, 11%, 7%, 4%, 4% and 2%, respectively Thus, the job position is diverse and suitable for evaluation.

Ranking factors due to mean

Table 4.1 Ranking of method of applying circular economy in construction projects by average value

According to a 5-point Likert scale, an average score between 3 and 5 indicates that most survey respondents agree with the author's perspective on the variable in question In contrast, a mean value below 3 suggests that the majority of participants either disagree or hold a neutral stance regarding the author's viewpoint on that variable.

On the other hand, according to the principle of "half adjustment" (Ke et al., 2010a;

Li, 2003), the 29 design methods of circular economy practices in construction projects are divided into three main levels: very important (Mean value > 3.5), relative importance (2.5

≤ Mean value ≤ 3.5) and less critical (Mean value < 2.5)

As can be seen in the table above, in 29 modes of designing circular economy practices in construction projects; The XH-1 and XH-2 modalities have a minimum mean

33 of 3.28 < 3.5, so these two methods have little importance in research, which can be excluded from the list of survey methods.

Test the mean value and Cronbach's Alpha for each group of criteria

Criterion A - Factors related to Governmental/ Political risks

Average value of methods under to criterion A - Factors related to Governmental/ Political risks

Table 4.2 Ranking by average of design methods under to criterion A - 'Factors related to Governmental/Political risks'

In the realm of Criterion A, which focuses on Governmental and Political risks, three circular economic practices in construction projects stand out, demonstrating significant average values that indicate their importance to survey participants.

 CS-2: The ‘Lack of proper vision such as goals, objectives, targets, and indicators in regards to Circular Construction Project.’ –This method has an average of 3.82 and a standard deviation of 0.852

 CS-6: The ‘Lack of construction industry incentives for ‘greener’ activities ’ –

This method has an average of 3.78 and a standard deviation of 0.956

 CS-4: The ‘Lack of political support and incentives to circular economy practices.’ –This method has an average of 3.78 and a standard deviation of 1.001

Cronbach's Alpha test for methods belonging to criterion A -'Factors related to Governmental/Political risks’

Table 4.3 Cronbach's Alpha test results for design methods under to criterion A - 'Factors related to Governmental/Political risks’

Scale Variance if Item Deleted

Cronbach’s Alpha if Item Deleted

The test results indicated that Criterion A achieved a Cronbach's Alpha reliability coefficient of 0.781, exceeding the acceptable threshold of 0.6 Additionally, all observed variables demonstrated a variable-total correlation greater than 0.3, confirming the reliability of the scale and the effectiveness of the survey methods for this criterion.

Criterion B - Factors related to Technical risks

Average value of methods under to criterion B- Factors related to Technical risks

Table 4.4 Ranking by average of design methods under to criterion B – Factors related to

Criterion B focuses on technical risks, highlighting three circular economic practices in construction projects that yield significant average values These practices are crucial for assessing participant feedback and demonstrate a high level of importance in the industry.

 KT-3: The ‘Lack of specifications for circular construction.’ –This method has an average of 3.76 and a standard deviation of 1.005

 KT-6: The ‘Limited experience of the consultant about Circular Economy practices in construction project.’ –This method has an average of 3.75 and a standard deviation of 1.066

 KT-5: The ‘Service life of Circular Material.’ –This method has an average of 3.63 and a standard deviation of 1.031

Cronbach's Alpha test for methods belonging to criterion B - Factors related to Technical risks

Table 4.5 Cronbach's Alpha test results for design methods under to criterion B - Factors related to Technical risks

Scale Variance if Item Deleted

Cronbach’s Alpha if Item Deleted

The test results showed that: (1) the Cronbach's Alpha scale reliability coefficient of Criterion B was equal to 0.735 > 0.6 and (2) the observed variables all had a Corrected

Item (Total Correlation) greater than 0.3 Thus, the scale of reliability, the survey methods all have good interpretation for this criterion

Criterion C - Factors related to Economic/financial risks

Average value of methods under to criterion B- Factors related to Economic/financial risks

Table 4.6 Ranking by average of design methods under to criterion C - Factors related to

In the context of Criterion A, which addresses governmental and political risks, three circular economic practices in construction projects have been identified These methods not only demonstrate significant average values but also indicate a high level of importance as perceived by survey participants.

 TC-5: The ‘High Upfront Cost.’ –This method has an average of 4.06 and a standard deviation of 0.805

 TC-3: The ‘The higher price difference between recycled products and virgin product.’ –This method has an average of 3.75 and a standard deviation of 0.884

 TC-1: The ‘Complex Cash Flow due to increase in stakeholders.’ –This method has an average of 3.72 and a standard deviation of 1.107

Cronbach's Alpha test for methods belonging to criterion C - Factors related to Economic/financial risks

Table 4.7 Cronbach's Alpha test results for design methods under to criterion C - Factors related to Economic/financial risks

Scale Variance if Item Deleted

Cronbach’s Alpha if Item Deleted

The test results indicated that Criterion C demonstrated a Cronbach's Alpha scale reliability coefficient of 0.748, exceeding the acceptable threshold of 0.6 Additionally, all observed variables exhibited a Corrected Item (Total Correlation) greater than 0.3, confirming that the reliability scale and survey methods provide strong interpretative value for this criterion.

Criterion D - Factors related to Market risks

Average value of methods under to criterion D - Factors related to Market risks

Table 4.8 Ranking by average of design methods under to criterion D - Factors related to

Criterion D focuses on market risks, highlighting two circular economic practices in construction projects that significantly impact participants These methods demonstrate substantial average values, indicating their importance in the assessment process.

 TT-3: The ‘Shortage in labor skilled in Circular Economy practices in construction project.’ –This method has an average of 3.78 and a standard deviation of 1.001

 TT-2: The ‘Time-consuming and labor-intensive remanufacturing procedure ’ –

This method has an average of 3.63 and a standard deviation of 1.141

 Cronbach's Alpha test for methods belonging to criterion D - Factors related to Market risks

Table 4.9 Cronbach's Alpha test results for design methods under to criterion D - Factors related to Market risks

Scale Variance if Item Deleted

Cronbach’s Alpha if Item Deleted

The test results indicated that Criterion D had a Cronbach's Alpha reliability coefficient of 0.707, exceeding the acceptable threshold of 0.6 However, the observational variables d-1 and d-9 displayed variable-total correlations below 0.3, prompting their removal for further testing.

Criterion F - Factors related to Organizational risks

Average value of methods under to criterion F - Factors related to Organizational risks

Table 4.10 Ranking by average of design methods under to criterion F- Factors related to

Under Criterion F – ‘Factors Related to Organizational Risks,’ two circular economic practices in construction projects have been identified, demonstrating significant average values that indicate a high level of importance to survey participants.

 RR-3: The ‘Poor-relationships between supply chain partners.’ –This method has an average of 3.90 and a standard deviation of 0.828

 RR-1: The ‘Lack of awareness for circular construction practices.’ –This method has an average of 3.82 and a standard deviation of 0.902

 Cronbach's Alpha test for methods belonging to criterion F- Factors related to Organizational risks

Table 4.11 Cronbach's Alpha test results for design methods under to criterion F- Factors related to Organizational risks

Scale Variance if Item Deleted

Cronbach’s Alpha if Item Deleted

The test results indicated that the Cronbach's Alpha reliability coefficient for Criterion E was 0.629, surpassing the acceptable threshold of 0.6 Additionally, all observed variables exhibited a variable-total correlation greater than 0.3 Consequently, both the scale reliability and survey methods demonstrate strong interpretative validity for this criterion.

Criterion G - Factors related to Logistics risks

Average value of methods under to criterion G- Factors related to Logistics risks

Table 4.12 Ranking by average of design methods under to criterion G- Factors related to

Under Criterion G, which focuses on logistics risks, two circular economic practices in construction projects are highlighted These methods demonstrate significant value, indicating a high level of assessment that is crucial for survey participants.

 LO-1: The ‘Improper location selection of depots and containers.’ –This method has an average of 3.82 and a standard deviation of 0.852

 LO-2: The ‘Improper selection of size, type, and capacity of the transport fleet in construction project.’ –This method has an average of 3.78 and a standard deviation of 0.956

Cronbach's Alpha test for methods belonging to criterion G - Factors related to Logistics risks

Table 4.13 Cronbach's Alpha test results for design methods under to criterion G - Factors related to Logistics risks

Scale Variance if Item Deleted

Cronbach’s Alpha if Item Deleted

The test results indicated that the Cronbach's Alpha reliability coefficient for Criterion F was 0.742, exceeding the acceptable threshold of 0.6 Additionally, all observed variables demonstrated a variable-total correlation greater than 0.3 Therefore, both the scale reliability and survey methods provided strong support for this criterion.

Results after analysis

The study identified 27 critical risks associated with implementing circular economy practices in construction projects, as evidenced by mean scores exceeding 3.5 and Cronbach’s Alpha values greater than 0.6.

The three elements of the circular economy practice application model in construction projects with the highest mean values demonstrate the high importance placed on them by the respective respondents:

 TC-5: The 'High Upfront Cost' (under to criterion C- Factors related to Economic/financial risks)– This method has the highest mean value of 4.06 and standard deviation of 0.805

 RR-3: The ‘Poor-relationships between supply chain partners.’ (under to criterion

F- Factors related to Organizational risks) – This method has a second-highest mean of 3.90 and a standard deviation of 0.828

The Circular Construction Project faces significant challenges due to a lack of clear vision, including defined goals, objectives, targets, and indicators This issue falls under criterion A, which addresses governmental and political risks The project's average score in this area is 3.82, with a standard deviation of 0.852, indicating variability in the perception of its vision clarity.

The survey results highlight key factors influencing the adoption of circular economic practices in construction projects Participants identified the 'High Upfront Cost,' 'Poor Relationships between Supply Chain Partners,' and the 'Lack of Proper Vision, including Goals, Objectives, Targets, and Indicators' as critical elements in developing an effective model for circular construction.

Post-inspection results: After testing Cronbach's Alpha scale and Mean value in SPSS software, we have 2 methods eliminated respectively:

 XH-1( Mean value: 2.97 < 3.5): Negative Effect of Circular practices on Employment, (under to criterion E- Factors related to Social risks)

 XH-2( Mean value: 3.18 < 3.5): Lack of consumer’s knowledge about reused materials, (under to criterion E- Factors related to Social risks)

The remaining methods will be used to build the FSE assessment model

FSE analysis

Calculate the FSE Method

In section 3.3.3, the Fuzzy Synthetic Evaluation (FSE) theory is applied to equations (1) through (5) to calculate the weight of each variable, along with the total weight for each criterion group, as detailed in the subsequent tables.

Table 5.1 Weighted analysis results of design methods & criteria groups

Symbol Average value of each method variable

Average value of each Criteria group

Weighting of each group of Criteria

Calculate the member function (MF – membership function of an element in the fuzzy set) for FSE analysis:

The MF of a particular modal variable was calculated from the statements of 136 respondents on a scale

For example, the results showed that 1.47% of respondents rated "Lack of effective recycling policies in waste management." (CS-1 method) is a very low level effect, 7.35%

47 is a low level influence, 41.18% is a moderate influence, 30.88% is a fairly high level influence, 19.12% is a high level influence Thus, the MF of the CS-1 Method is presented as follows:

The MF of this CS-1 method can also be expressed as a matrix (rounded to 3 decimal units):

Applying the same calculation, the MF of the remaining Method variables is calculated and shown as in Table 5-1

After calculating the MF for all Method variables, the MF of each Criterion element is also evaluated using the equation (3) from section 3.3.3) Fuzzy Synthetic Evaluation (FSE) theory

Taking Criterion A as an example, the weights of all Method variables under this Criterion are presented as follows:

Accordingly, the MF of this Criterion is calculated as follows:

Similarly, the MF of the remaining Criteria elements is calculated and presented in column 4 of Table 5-2 as follows:

Table 5.2 MF analysis results of design methods & criteria groups

Symbol Weight of each variable MF of each method variable MF of each group of Criteria

The evaluation of the Master of Design Criteria (level 1) involves assessing the weighted significance of six criteria along with their respective Master Factors (MF) The findings are summarized in Table 5-3.

Table 5.3 MF analysis results of each group Criteria & Overall

Symbol Weight of each criteria MF of each group of Criteria MF Overall Criteria (level 1)

The coefficient for each Criterion factor is then calculated by applying the equation

(5) from section 3.3.3) Fuzzy Synthetic Evaluation (FSE) theory as shown in Table 5.4, with:

CFIIA = [0.013 0.111 0.280 0.347 0.238] x [1 2 3 4 5] = 2.074 CFIIB = [0.023 0.111 0.282 0.354 0.230] x [1 2 3 4 5] = 3.655 CFIIC = [0.026 0.066 0.270 0.407 0.231] x [1 2 3 4 5] = 3.751 CFIID = [0.030 0.124 0.261 0.345 0.229] x [1 2 3 4 5] = 2.443 CFIIF = [0.005 0.071 0.261 0.443 0.233] x [1 2 3 4 5] = 3.828 CFIIG = [0.044 0.125 0.206 0.401 0.224] x [1 2 3 4 5] = 3.636 CFIItt = [0.022 0.102 0.270 0.379 0.234] x [1 2 3 4 5] = 3.720(*)

Table 5.4 Coefficient of each Criteria group

Symbol CFII Coefficient of each Criteria group

A composite index is developed using a model to assess the significance of the Survey Design Criteria, ensuring that the final results are easy to interpret and intuitive for users.

The CFII value for each Criterion is normalized, and the final CFII is derived from the combination of six standardized indices The evaluation of CFII results is conducted based on this comprehensive analysis.

CF II = (0.14 * Criterion A) + (0.18 * Criterion B) + (0.19 x*Criterion C) + (0.12 * Criterion D) + (0.19 * Criterion F) + (0.18 * Criterion G)

Table 5-4 highlights the variations in weights influenced by distinct factors, as detailed in Table 4.1 The weight calculations are derived from the average values obtained during step 3 of the FSE procedure These initial results were subsequently utilized in the fuzzy system, following the methodologies outlined in steps 4, 5, and 6 of the FSE procedure.

52 to calculate the normalized indices for each design criterion Therefore, the weights assigned to each Design Criteria have different values and rankings between the two tables

This value is similar to the CF II result calculated by matrix multiplication (*) above

The results are obtained after calculation:

Through the results of FSE analysis, the circular economy practices in the construction project design criteria groups are ranked as follows:

 Criterion F - 'Factors related to Organizational risks' has the highest coefficient of "0.191"

Criterion C, which addresses economic and financial risks, ranks second with a coefficient of 0.187 Following closely are Criterion B, focusing on technical risks, and Criterion G, which pertains to logistics risks, both sharing a coefficient of 0.183.

 Next is Criterion A- ‘Factors related to Governmental/Political risks’ with coefficient "0.135"

 Criterion D- ‘Factors related to Market risks’ is rated lowest with the coefficient

Case study of FSE Method

5.2.1 Case study of Circular economy practices in construction project

Table 5.5 Model for applying Circular Economy Design Criteria in construction projects based on FSE calculations

Order of priority APPLICABLE DESIGN CRITERIA COEFFICIENT

1 Criterion F - ‘Factors related to Organizational risks’

RR-3 Poor-relationships between supply chain partners

RR-Poor leadership and management towards circular economic in construction project

RR1-2 Lack of awareness for circular construction practices

2 Criterion C- ‘Factors related to Economic/financial risks’

TC-1 Complex Cash Flow due to increase in stakeholders

TC-3 The higher price difference between recycled products and virgin product

TC-2 Inflation of circular materials

TC-4 Profit Uncertainty of Circular Construction

3 Criterion B - ‘Factors related to Technical risks’ ~0.18 (0.183)

KT-3 Lack of specifications for circular construction 0.15

KT-6 Limited experience of the consultant about Circular Economy practices in construction project

KT-5 Service life of Circular Material

KT-7 Limited experience of the contractor about Circular Economy practices in construction project

4 Criterion G - ‘Factors related to Logistics risks’ ~0.18 (0.182)

G-1 Improper location selection of depots and containers

G2 Improper selection of size, type, and capacity of the transport fleet in construction project

5 Criterion A - ‘Factors related to Governmental/

CS-2 Lack of proper vision such as goals, objectives, targets, and indicators in regards to Circular Construction Project

CS-4 Lack of political support and incentives to circular economy practices

CS-6 Lack of construction industry incentives for ‘greener’ activities

CS-1 Lack of effective recycling policies in waste management

CS-3 Lack of sufficient law implementation in circular construction projects

6 Criterion D - ‘Factors related to Market risks’ ~0.12 (0.122)

TT-3 Shortage in labor skilled in Circular Economy practices in construction project

TT-2 Time-consuming and labor-intensive remanufacturing procedure

TT- Lack of continuous customer interest and attention

TT-1 Lack of proper mechanism for take- back

Table 5.5 assesses the ranking of criteria within each group by considering the coefficient and weight of each criterion Utilizing these factors, we can develop a practical model Below, we present a case study demonstrating the application of the FSE model to the circular economy, informed by a survey of experts involved in projects that have integrated circular economy principles throughout their processes.

A construction company is developing a new office building while aiming to integrate circular economy (CE) principles into the project To achieve this, they must assess various construction methods and identify potential risks associated with implementing circular economy strategies in their projects.

To comprehend the potential risks associated with implementing circular economy activities in projects, the company conducted research and sought guidance from experts involved in six projects that have integrated circular economy principles into their processes Detailed information about these projects is presented in Table 5.6.

Table 5.6: Profiles of six demonstrative construction project

Processes of circular economy activities

Civil, Industrial and Building construction

Head of the design department

Civil, Industrial and Building construction

Engineer/Arc hitect Foreign capital

Building construction and urban development

Civil, Industrial and Building construction

Head of bidding team Private capital

Note: (1) Design for Durability and Adaptability: Designing buildings with high- quality materials and adaptable layouts that can accommodate future changes, reducing the need for demolition and reconstruction

Incorporating recycled and upcycled materials into new construction minimizes the dependence on virgin resources while fostering the creation of distinctive architectural features By utilizing materials from previous projects or repurposed items from various industries, builders can promote sustainability and innovation in their designs.

(3) Sustainable Procurement: Prioritizing sourcing materials from local suppliers, reducing transportation emissions and supporting the local economy This also contributes to reducing the project's carbon footprint

Implementing waste minimization strategies on-site, such as optimized cutting techniques and effective material handling, significantly reduces waste generation Additionally, segregating waste materials enhances recycling and reuse efforts, effectively diverting them from landfills.

Refurbishment and renovation focus on revitalizing existing structures through upgrades instead of demolition, which helps preserve valuable materials and embodied energy This approach not only extends the lifespan of buildings but also enhances their energy efficiency and allows for adaptation to new uses.

Table 5.7 Model represents Weightings and membership function of Circular Economy Practices (CEP) in Construction Projects and categories

CS-1: Lack of effective recycling policies in waste management 0.162 0.0219 26 5 3 4 4 4 4

CS-2: Lack of proper vision such as goals, objectives, 0.173 0.0233 23 5 3 4 3 5 3

58 targets, and indicators in regards to

CS-3: Lack of sufficient law implementati on in circular construction projects 0.160 0.0217 27 5 3 5 5 4 4

CS-4: Lack of political support and incentives to circular economy practices 0.171 0.0231 24 5 5 3 3 4 5

CS-6: Lack of construction industry incentives for

KT-3: Lack of specifications for circular construction 0.147 0.0269 15 4 5 3 5 5 3

Limited experience of the consultant about

Economy practices in construction project 0.147 0.0268 16 5 5 4 3 5 2

Limited experience of the contractor about

Cash Flow due to increase in stakeholders 0.200 0.0376 7 4 5 3 3 4 2

TC-3: The higher price difference between recycled products and virgin product 0.199 0.0373 8 5 5 2 5 4 4

TT-1: Lack of proper mechanism for take-back 0.244 0.0297 14 4 5 3 4 4 5

TT-2: Time- consuming and labor- intensive remanufacturi ng procedure 0.251 0.0306 12 3 5 4 3 5 4

Shortage in labor skilled in Circular

Economy practices in construction project 0.261 0.0318 11 3 5 3 4 5 5

TT-4: Lack of continuous customer interest and attention 0.245 0.0299 13 4 5 3 5 5 3

RR-1: Lack of awareness for circular construction practices 0.333 0.0637 4 4 3 3 5 4 1

62 management towards circular economic in construction project

RR-3: Poor- relationships between supply chain partners 0.339 0.0649 3 4 3 4 4 5 4

Improper location selection of depots and containers 0.501 0.0909 1 5 4 4 4 4 2

Improper selection of size, type, and capacity of the transport fleet in construction project 0.499 0.0907 2 3 4 3 3 5 1

Note: Project is abbreviated as P (Project = P)

Overall weight = Group weight X Local weight

Circular economy practices in construction project results (CEP) vary significantly, ranging from 2,879 to 4,429 Notably, Project 5 achieves the highest score of 4,429 by implementing a comprehensive range of circular economy criteria, including Design for Durability and Adaptability, as well as Recycled and Upcycled materials.

Materials, Sustainable Procurement, Waste Minimization and Segregation,

Refurbishment and renovation practices were evaluated based on five criteria agreed upon by experts, with Project 6 scoring the lowest at 2,879 due to applying only 2 out of 5 criteria In contrast, Projects 1 and 2 demonstrated strong performance with scores of 4,166 and 4,146, respectively, both incorporating 4 out of 5 circular economy practices Project 3 exhibited below-average practices, while Project 4 met the average level Interviewees identified Projects 1, 2, and 4 as the leading contractors in implementing circular economy practices, whereas Projects 3 and 5 had average investment capital and experience Project 6 lagged in circular economy application, attributed to its limited experience and smaller enterprise scale.

Figure 5.1 Circular economy practices levels of six demonstrative construction projects

Implication

This study identified 27 significant risks associated with implementing circular economy practices in construction projects, with an average score exceeding 3.5 A key objective was to explore methods for promoting circular economy adoption across construction companies of varying sizes A comparative analysis of three construction enterprise groups revealed that while there were minor differences in risk ratings, these were not statistically significant, suggesting that all company sizes can effectively integrate circular economy practices Governmental and political risks were particularly influential for small and medium-sized firms, while larger organizations focused more on organizational risks These insights can help construction companies enhance their circular economy strategies, ultimately boosting productivity and corporate performance through environmental sustainability, and aligning with previous studies that indicate improved financial efficiency through such practices.

[47] , business performance[48] and competitive advantage [49]

The study identifies key factors influencing the application of circular economy practices in construction projects, highlighting organizational risks with an importance index of 3.828 and economic/financial risks at 3.751 These findings align with recent research indicating the significant role these risks play in implementing circular economy strategies within the construction industry.

Implementing circular economy practices in construction projects can significantly reduce material consumption, pollution, and promote the reuse of materials, ultimately enhancing project performance and offering a competitive advantage Construction companies of all sizes are encouraged to refine their production processes to align with these sustainable practices, achieving both economic and environmental objectives The final FSE model serves as a valuable tool for practitioners, enabling them to assess the overall impact of risk assessment models related to circular economy applications Additionally, this model facilitates the comparison of circular economy practices across multiple projects, thereby enhancing the sustainability and efficiency of the construction industry These insights are crucial for promoting the adoption of circular economy practices in developing countries, paving the way for a greener and more efficient future in construction.

Conclusion

Circular economy practices offer a practical solution for conserving resources and addressing pressing environmental challenges, thereby fostering sustainable development However, implementing these practices in construction projects can be difficult and prone to errors due to their inherent complexity and ambiguity.

The research involved a thorough literature review to identify and analyze 29 risks associated with circular economy practices in construction projects in Vietnam A risk assessment model was developed, which quantified the overall risk at 3.720 on a 5-point Likert scale, highlighting the significant risks involved in implementing these practices The findings indicated that investment in circular economy practices in the construction sector is fraught with risks that require careful consideration Notably, the model identified government/political risks with a risk index of 2.074 and technical risks, underscoring the need for strategic planning in this area.

Risk-related factors such as economic/financial (Risk index = 3.751), market (Risk index = 2.443), organizational (Risk index = 3.828), and logistics (Risk index = 3.363) significantly threaten the successful implementation of circular economy practices in construction projects This study provides statistically significant evidence of the importance of these practices within construction companies Unlike previous research that treated circular economy practices as independent or dependent variables, this work integrates various aspects of circular economy management in the construction industry, contributing to a growing body of literature By developing a composite index to assess the level of circular economy application, this study enhances understanding and promotes the sustainability of the construction sector, particularly in developing countries.

This study highlights the implementation of circular economy practices in the construction sector by assessing key factors and risks, while offering a reliable tool for quantifying these practices among construction companies The findings can guide policy development for circular economy initiatives in Vietnam and similar developing nations, addressing various aspects of innovation such as policy, technology, and management The tool enables construction firms to accurately evaluate their circular economy practices, facilitating the creation of effective strategies and compliance with stringent environmental regulations This could encourage organizations of all sizes to adopt circular economy practices, ultimately reducing the environmental impact of the construction industry globally However, the study has limitations, including reliance on empirical data from Vietnamese construction companies, suggesting the need for future research in diverse project-based organizations and other developing countries Additionally, the use of a non-probability sampling method may introduce biases, indicating that future studies should employ probability sampling techniques for more robust results.

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SURVEY QUESTIONNAIRE DEVELOPING A RISK ASSESSENT MODEL FOR CIRCULAR ECONOMY

T My name is Tran Le Duy, currently a Master's student in Construction Management,

I am currently pursuing my graduation thesis at Ho Chi Minh City University of Technology, focusing on "Developing a Risk Assessment Model for Circular Economy Practices in Construction Projects." This research aims to identify potential risks associated with circular economy practices in the construction sector and propose effective solutions to mitigate these risks, ultimately enhancing the efficiency of construction project operations.

Your input is crucial for the success of this research, and rest assured that all information will remain confidential and used solely for research purposes We are excited to share the results of this study with you and appreciate your attention and assistance Thank you sincerely for your support!

If you have comments or are interested in the results of this study, please contact: Trần Lê Duy ĐT: 0367494194 Email: tranleduy98@gmail.com

PART A: ASSESSMENT OF FACTORS IMFLUENCING THE

IMPLEMENTATION OF CIRCULAR ECONOMY PRACTICES IN

This article introduces a risk assessment survey focused on the values of circular economy (CE) practices in construction projects The circular economy represents an innovative economic model aimed at resource efficiency, waste reduction, and environmental protection, increasingly adopted in the construction industry Key benefits of CE include cost reduction through the use of recycled materials, enhanced environmental protection by minimizing waste, and improved resource efficiency via material reuse and adaptable designs However, implementing CE in construction also presents certain risks, which are detailed in a table outlining factors that influence these risks.

In the assessment table for evaluating circular economy practices in construction projects, participants can indicate their level of agreement by marking "X" in one of five boxes, which range from 1 (Totally disagree) to 5 (Totally agree) Additionally, respondents can note any other relevant causes that may influence their perspective.

Please provide information about the construction projects you have mainly participated in and assess the impact of the risks (listed below)

A Factors related to Governmental/ Political risks

1 Lack of effective recycling policies in waste management

Lack of proper vision such as goals, objectives, targets, and indicators in regards to Circular Construction Project

Lack of sufficient law implementation in circular construction projects

Lack of political support and incentives to circular economy practices

Lack of construction industry incentives for ‘greener’ activities

B Factors related to Technical risks

9 Lack of specifications for circular construction

11 Service life of Circular Material

12 Limited experience of the consultant about Circular

Economy practices in construction project

13 Limited experience of the contractor about Circular

Economy practices in construction project

Please provide information about the construction projects you have mainly participated in and assess the impact of the risks (listed below)

C Factors related to Economic/financial risks

14 Complex Cash Flow due to increase in stakeholders

16 The higher price difference between recycled products and virgin product

17 Profit Uncertainty of Circular Construction

D Factors related to Market risks

19 Lack of proper mechanism for take-back

20 Time-consuming and labour-intensive remanufacturing procedure

21 Shortage in labour skilled in Circular Economy practices in construction project

22 Lack of continuous customer interest and attention

E Factors related to Social risks

23 Negative Effect of Circular practices on Employment

24 Lack of consumer’s knowledge about reused materials

F Factors related to Organizational risks

25 Lack of awareness for circular construction practices

26 Poor leadership and management towards circular economic in construction project

27 Poor-relationships between supply chain partners

G Factors related to Logistics risks

28 Improper location selection of depots and containers

29 Improper selection of size, type, and capacity of the transport fleet in construction project

PHẦN B: ĐÁNH GIÁ VỀ CÁC DỰ ÁN XÂY DỰNG ĐÃ THỰC HIỆN

Anh/Chị vui lòng chọn một trong những đáp án sau bằng cách đánh dấu “×” vào

B1 Loại dự án mà Anh/Chị tham gia chủ yếu

Chung cư Cao ốc văn phòng Nhà hàng Khu du lịch/Resort

Khách sạn Khu phức hợp Nhà ở xã hội Khác: ………

B2 Nguồn vốn của các dự án vừa kể trên (ở mục B1)?

Vốn ngân sách Vốn tư nhân Vốn nước ngoài Khác: ……… B3 Quy mô của dự án này ra sao?

10-20 tỷ 20-100 tỷ 100-200 tỷ 200-500 tỷ 500-1000 tỷ

C1 Anh/Chị đang công tác trong Công ty/ trong dự án với vai trò?

Chủ đầu tư/ Ban QLDA Tư vấn QLDA/TVGS I Nhà cung cấp cung cap

Nhà thầu Chính Tư vấn Thiết kế I Khác (……….)

C2 Bạn đang làm việc tại công ty hoặc dự án nào với vai trò cụ thể? Các vị trí có thể bao gồm: Chủ doanh nghiệp, Giám đốc, Trưởng hoặc Phó Ban Quản lý Dự án, Kỹ sư, Kiến trúc sư, Giám đốc hoặc Phó Giám đốc Dự án, Chỉ huy trưởng hoặc Phó, Chủ trì thiết kế, Quản lý, Trưởng hoặc Phó phòng, Giám sát trưởng hoặc Phó, hoặc các vị trí khác (nêu rõ).

C3 Anh/Chị đang công tác trong ngành xây dựng khoảng thời gian bao lâu? i1-3 năm I i3-5 năm 5-10 năm I 10-15 năm I15-20 năm I>20 năm

C4 Anh/Chị đánh giá mức độ hiểu biết của bản thân về vấn đề khí thải carbon trong công trình?

Không biết Có hiểu biết, nhưng còn ít Biết tương đối nhiều Biết rất rõ

C5 Nếu có thể, Anh/Chị vui lòng cung cấp các thông tin cá nhân để trao đổi thêm khi cần thiết