SUSTAINABLE DEVELOPMENT-BASED ASSESSMENT METHOD FOR CONSTRUCTION PROJECTS IN VIETNAM: APPLICATION TO BRIDGES USING ULTRA-HIGH PERFORMANCE CONCRETE

Research purpose and objectives Research purpose: Proposing a general method for evaluating CWs from a SD perspective and develop a specific evaluation model for bridges using UHPC.. R

MINISTRY OF EDUCATION AND TRAINING

HANOI UNIVERSITY OF CIVIL ENGINEERING

Tran Duc Binh

SUSTAINABLE DEVELOPMENT-BASED ASSESSMENT METHOD FOR CONSTRUCTION PROJECTS IN VIETNAM: APPLICATION TO BRIDGES USING ULTRA-HIGH

The dissertation was completed at Hanoi University of Civil Engineering

Scientific Supervisor 1: Prof Dr Nguyen Van Tuan

Scientific Supervisor 2: Assoc Prof Dr Pham Xuan Anh

Reviewer 1: Assoc Prof Dr Nguyen Luong Hai

Reviewer 2: Assoc Prof Dr Le Van Chinh

Reviewer 3: Dr Tran Ba Viet

The dissertation will be defended before the Institutional Dissertation Evaluation Council at Hanoi University of Civil Engineering

The dissertation can be accessed at the National Library and the Library of Hanoi University of Civil Engineering

INTRODUCTION

1 Reason for choosing the topic

The evaluation of construction works (CWs) is a common task for experts, construction investors, and operators involved in the management, exploitation, and use of CWs This process helps to select the most suitable and profitable construction investment and operation methods, maximizing efficiency Therefore, today, the comprehensive evaluation of CWs in terms of environmental impact, economic impact, and social impact is an essential need This approach aligns with the sustainable development (SD) goals set by the United Nations since the 1980s and has increasingly gained global support from many countries and organizations

Vietnam has committed strongly to environmental protection and climate change adaptation As Prime Minister Pham Minh Chinh highlighted at the United Nations Climate Change Conference (COP26) in 2021, the country aims to reduce national emissions by 43.5% by 2030 and achieve net-zero carbon emissions by 2050 The impacts of CWs on the environment, economy, and society extend throughout the entire life cycle, not just at a single point or stage Therefore, evaluating CWs requires consideration of their entire life cycle This dissertation will utilize the Life Cycle Thinking (LCT) approach to address the challenge of evaluating CWs from a SD perspective

In recent years, Ultra-High Performance Concrete (UHPC), a new generation of concrete with outstanding properties in terms of workability, mechanical characteristics, and long-term durability, has been researched, developed, and applied in certain types of CWs Compared to traditional materials, UHPC is considered less advantageous during the construction phase due to high investment costs and complex techniques However, it has clear advantages in the service phase of the structure and in terms of environmental aspects Nevertheless, in order to make an informed decision regarding the selection of construction methods, it is essential to adopt a comprehensive evaluation approach based on SD principles This evaluation must consider the entire life cycle of the CWs to provide a holistic view of the research issue

Based on these observations, I have chosen the topic "Sustainable development-based assessment method for construction projects in Vietnam: application to bridges using ultra-high performance concrete" for my doctoral dissertation

2 Research purpose and objectives

Research purpose: Proposing a general method for evaluating

CWs from a SD perspective and develop a specific evaluation model for bridges using UHPC The proposed general method aims to assist project investors in selecting the best design solution that aligns with

SD goals

Research objectives:

- Systematize the theoretical foundation on the life cycle of CWs,

SD, and methods for evaluating CWs;

- Propose a method for evaluating CWs in general from a SD perspective, applying LCT;

- Propose an evaluation model for bridges using UHPC from a SD perspective;

- Develop an environmental data set for building materials (BMs) suitable for the conditions in Vietnam to support the evaluation

of bridges using UHPC;

- Apply the proposed evaluation model for bridges using UHPC for a specific bridge project

3 Object and Scope of the Study

Object: The study focuses on the evaluation method for CWs

from a SD perspective, meaning an integrated evaluation that considers the three aspects: environmental, economic, and social aspects

Scope: The research not only studies the theoretical methods for

evaluating CWs in general but also investigates the evaluation model for bridges using UHPC specifically In terms of the scope of evaluating the impacts of CWs, the study focuses on three aspects from the SD perspective: environmental, economic, and social pillars The research does not address the technical aspects of evaluating CWs, as the construction options must first meet technical requirements before being evaluated The evaluation method proposed

in this study will consider the impacts of CWs throughout the entire life cycle of the construction project

4 Approaches and research methods

To achieve the research objectives, the dissertation has approached the theory of the three aspects of SD — environmental, economic, and social — as well as the theory of LCT and methods for evaluating environmental, economic, and social impacts throughout the life cycle of a product These theories and methods have been proposed and applied in practice to be utilized and supplemented in the process of researching and proposing a method for evaluating CWs from a SD perspective

In this dissertation, I has used the following research methods:

- Methodology: The study uses the dialectical materialism and historical materialism methodology;

- Theoretical research method: This method involves collecting, analyzing, and synthesizing theoretical knowledge to provide an overview of the research, identify research gaps, determine research objectives, build the theoretical foundation, and propose

an evaluation method for CWs from a SD perspective;

- Practical research method: This method uses bridge design models, quantity surveying and cost estimation techniques, as well as methods for evaluating environmental, economic, and social impacts to assess bridges from a SD perspective;

- Combination of qualitative and quantitative research methods: This includes in-depth interviews with experts in the construction field, surveys, and the complexity ratio evaluation method to determine the indicators and their weights to be included in the evaluation model The results of the evaluation will be analyzed for three design options from a SD perspective

5 Novel contributions of the dissertation

- Propose a general method for evaluating CWs from a SD perspective, which serves as a foundation for developing evaluation models for different types of CWs according to the

SD perspective

- Develop a SD perspective evaluation model for medium and small-scale bridge projects using UHPC This evaluation model has been applied to assess the specific project of constructing the

An Thuong rural bridge

- Develop an environmental database for Portland cement that is suitable for the cement production conditions in Vietnam

6 Scientific and practical significance of the dissertation

6.1 Scientific significance

The dissertation enriches the theory of CWs evaluation by proposing a general method for evaluating CWs from a SD perspective The proposed evaluation method from the SD perspective

is a valuable tool for developing evaluation models for different types

of CWs

6.2 Practical significance

In practical terms, the dissertation has developed an evaluation model for bridges using UHPC with medium and small scale This evaluation model has also been successfully applied to a real-world bridge project It serves as a useful tool for construction investors during the design phase, helping them make decisions on selecting the optimal design option from a SD perspective

By developing an environmental database for Portland cement suitable for the conditions in Vietnam, the dissertation makes a significant contribution to the practice of Life Cycle Assessment (LCA) in the context of Vietnam, where no existing databases are available for assessing environmental impacts in the construction and BMs industry

7 Structure of the dissertation

The dissertation is presented in 153 A4 pages, excluding the References and Appendices, and consists of the following sections: Introduction, Chapter 1 (39 pages), Chapter 2 (31 pages), Chapter 3 (50 pages), Chapter 4 (26 pages), Conclusion, with 47 tables and 29 figures

CHAPTER 1: OVERVIEW OF RELATED RESEARCHES ON THE DISSERTATION TOPIC

1.1 Overview of related researches on construction works evaluation based on life cycle thinking and sustainable development perspective

1.1.1 Overview of researches on construction works evaluation based on life cycle thinking

1.1.1.1 Overview of researches on construction works evaluation based on life cycle thinking from an environmental aspect

A total of 48 research studies on the environmental aspect in the construction field are reviewed These studies are categorized into six groups, including BMs, bridges, roads, buildings, building components, and other types of construction

1.1.1.2 Overview of researches on construction works evaluation based on life cycle thinking from an economic aspect

A total of 37 research studies on the economic aspect in the construction field are reviewed, categorized into six research subjects similar to Section 1.1.1.1 These studies are then analyzed based on the life cycle evaluation scope, evaluation indicators, analysis period, discount rate, and inflation rate

1.1.1.3 Overview of researches on construction works evaluation based on life cycle thinking from a social aspect

Among the researches reviewed, only 6 studies address social aspect These studies are analyzed based on the life cycle evaluation scope, types of evaluation indicators, and research methods used

1.1.2 Overview of researches on construction works evaluation from

a sustainable development perspective

A total of 42 research studies on CWs evaluation from a SD perspective, aimed at comparing technical options, are reviewed Among these, 25 studies address the evaluation of multiple aspects of

SD, but only 9 studies provide integrated evaluations for choosing technical options

1.2 Overview of related researches on construction projects using ultra-high performance concrete

1.2.1 Overview of related researches on ultra-high performance concrete materials

14 scientific articles on UHPC materials were selected and reviewed from technical, environmental, economic, and social perspectives

1.2.2 Overview of related researches on the application of ultra-high performance concrete

Overview of 23 research articles on the application of UHPC in construction field, specifically in transportation infrastructure

(bridges, highways, etc.), civil and industrial buildings, and other applications (thin-shell structures, blast-resistant structures, etc.)

1.3 Synthesis of literature review findings and identification of research gaps

- There is a lack of studies on comprehensive evaluation methods that simultaneously consider all three aspects (environmental, economic, and social) for comparing technical alternatives in construction;

- Many studies do not take into account the full life cycle of the research object;

- There is a shortage of environmental data when conducting LCA;

- Social impacts throughout the life cycle of CWs are rarely studied;

- Studies on the environmental, economic, and social aspects of UHPC and UHPC-based CWs are still very limited compared to studies focusing on the technical aspects of this material

1.4 Identification of the key issue to be addressed

- To develop an evaluation method for CWs from the perspective

of SD, meaning a comprehensive and integrated assessment of environmental, economic, and social aspects; to build a specific assessment model for bridges using UHPC;

- To apply LCT in the assessment method and model for CWs in general, and for UHPC-based bridges in particular;

- To develop an environmental data set for BMs based on production conditions in Vietnam, serving CWs assessments in general and LCA in particular

1.5 Research framework of the thesis and research methods

The research framework of the thesis is diagrammatically represented in Figure 1 To achieve the five research objectives of the study, the thesis combines various research methods, as detailed below:

- The method of theoretical analysis and synthesis through collecting and analyzing scientific papers and doctoral dissertations to systematize the theoretical foundation and propose a general method for assessing CWs from the perspective

of SD;

- The qualitative research method combined with quantitative

research through in-depth interviews with experts in the

construction field and using surveys with questionnaires to build

an evaluation model for bridges using UHPC;

- The method of collecting practical data to gather information on

the production of certain types of BMs to build an environmental

data set for BMs suited to the production conditions in Vietnam;

- The method of data analysis such as LCA, LCCA, S-LCA,

qualitative analysis, and quantitative analysis to apply the

evaluation model to a specific bridge project in Vietnam

Proposing an evaluation method for UHPC bridges from the perspective of SD

Developing an environmental dataset for BMs suitable for Vietnamese conditions

Evaluating a bridge in Vietnam from the perspective of SD

Theoretical analysis

and synthesis methods Delphi method

Sociological survey and investigation methods

Life-cycle assessment method

General method for

evaluating CWs from

the perspective of SD

Evaluation model for UHPC bridges from the perspective of SD

Environmental dataset for Portland cement materials suitable for Vietnamese conditions

Evaluation of An Thượng bridge from the perspective of SD

Practical data collection methods

Chapter 1 Chapter 2

Chapter 3 Chapter 4

Figure 1 Research framework of the thesis

CHAPTER 2 THEORETICAL FOUNDATION OF THE LIFE

CYCLE OF CONSTRUCTION WORKS AND EVALUATION

METHODS FOR CONSTRUCTION WORKS FROM THE

PERSPECTIVE OF SUSTAINABLE DEVELOPMENT

2.1 Theoretical foundation of the life cycle of construction works

2.1.1 Concept and classification of construction works

The concept and classification of construction works are

referenced and cited in the Construction Law No 50/2014/QH13 and

Decree No 06/2021/ND-CP

2.1.2 Life cycle of construction works

The life cycle of CWs includes the following stages: extraction and transportation of raw materials (A1, A2); production and transportation of construction materials/components (A3, A4); construction of the project (A5); operation and maintenance of the project (B); end-of-life of the project (C)

2.1.3 Life cycle thinking

LCT, primarily focused on sustainable production and consumption, represents the highest level of decision-making The impacts of all stages in the life cycle need to be comprehensively considered to make informed decisions about production and consumption models, as well as policies and management strategies

2.2 Some theories on sustainable development

2.2.1 Concept of sustainable development

A summary of the origin, concept, and role of SD SD is development that meets the needs of the present without compromising the ability of future generations to meet their own needs

2.2.2 Perspectives on sustainable development

SD includes three aspects: environmental (conservation), economic (growth), and social (equity), and these three aspects are closely interconnected In other words, development is considered sustainable when it meets the sustainability goals and requirements across all three areas: environmental, economic, and social

2.3 Theoretical foundation of construction work evaluation methods

2.3.1 Concept of construction work evaluation methods

The method of evaluating CWs can be understood as the approach to perceiving, studying, and assessing the value of CWs The value of CWs is not only measured in monetary terms but also assessed through various other criteria, depending on the scope of the evaluation

2.3.2 Evaluation methods for construction works based on different aspects of sustainable development

2.3.2.1 Evaluation method from an environmental perspective

Systematizing the theoretical foundation includes the concept, history of formation and development, methodology, environmental impact assessment indicators, and environmental data

2.3.2.2 Evaluation method from an economic perspective

Systematizing the theoretical foundation includes the concept, economic evaluation indicators, and parameters for assessment

2.3.2.3 Evaluation method from a social perspective

Systematizing the theoretical foundation on the concept and content of the method

2.3.2.4 General comments

The evaluation methods that focus on each individual aspect have the advantage of allowing the evaluator to gain a deep understanding

of the impacts of CWs in each area, with no limitations on the number

of indicators included in the evaluation However, a major disadvantage of these methods is the difficulty in comparing CWs designs, as the values of the aspects in different design alternatives tend to be contradictory or opposing

2.3.3 Evaluation method for construction works from the perspective of sustainable development

2.3.3.1 Integrated evaluation through monetization

Monetizing environmental impacts allows for the conversion of environmental effects into monetary terms, facilitating the evaluation

of both environmental and economic aspects However, environmental cost calculation methods are often difficult to implement due to the dependency on various factors such as space (geography), time (analysis period), and economic data (income levels

of individuals and countries) Additionally, not all impacts can be converted into monetary values Therefore, this approach can only be applied in a limited number of cases

2.3.3.2 Integrated evaluation through scoring system

One of the most feasible solutions for integrated evaluation is to convert the values of evaluation indicators into scores This way, the economic, environmental, and social values are brought to the same calculation level, facilitating comparison and selection of alternatives When evaluating through scores, it is necessary to eliminate the measurement units of the evaluation indicators, also known as normalizing the values of the indicators, before calculating the integrated score for these indicators The normalized value is the value

of the evaluation indicators after the measurement units have been

removed Subsequently, the normalized values will be processed using multi-criteria decision-making methods

2.4 Method for developing an environmental data set for construction materials suited to the conditions of Vietnam

The process of developing an environmental data set for BMs under the production conditions in Vietnam is carried out in four steps: Collecting data from the production process of BMs from factories in Vietnam (1); Selecting impact evaluation indicators (2); Choosing the evaluation method and calculation tools (3); Calculating and analyzing the data (4)

CHAPTER 3 PROPOSING METHOD FOR EVALUATING CONSTRUCTION WORKS FROM THE PERSPECTIVE OF SUSTAINABLE DEVELOPMENT

3.1 Proposing general method for evaluating construction works from the perspective of sustainable development

3.1.1 Goals and scope

The proposed general method for evaluating CWs from the perspective of SD aims to provide a theoretical foundation for building evaluation models tailored to specific types of CWs, assisting in the assessment, comparison, and selection of design alternatives

In terms of scope, this method comprehensively evaluates the three aspects of SD, including environmental, economic, and social factors, through an integrated scoring system At the same time, the method also considers and evaluates the potential impacts throughout the complete life cycle of the CWs, meaning it applies LCT to the evaluation of CWs

3.1.2 Theorical framework

The proposed theoretical framework for evaluating CWs from the perspective of SD is a diagram that illustrates the goals and the process for carrying out the evaluation of CWs, as shown in Figure 2

assessment indicators

Environmental impact

assessment indicators

Environmental database

Economic impact assessment indicators

Weights of economic assessment indicators

Life cycle environmental sustainability score Weights of

environmental assessment indicators

Integrated life cycle sustainability score

Expert opinion

Weight of economic pillar Weight of environmental pillar

Social impact assessment indicators

Life cycle social sustainability score Expert opinion

Weight

of social pillar

- Interpretation

- Ranking alternatives

- Making decision

Economic database

Life cycle economic sustainability score

Figure 2 The general process for evaluating CWs from the

perspective of SD

3.1.3 Procedure for implementing the general method

The general method for evaluating CWs from the perspective of

SD is carried out in three steps: Preparation and data collection (1); Evaluation of the CWs in terms of environmental, economic, and social aspects (2); Integrated evaluation from a SD perspective (3) Specifically, the environmental criteria group consists of 12 indicators, the economic criteria group includes 12 indicators, and the social criteria group has 11 indicators (Table 1)

Table 1 Proposing some evaluation indicators for CWs from the

This is a common environmental indicator used

to measure greenhouse gas emissions, which are converted into CO2