Usefulness of Adopting the last Planner System in the Construction Process of Addis Ababa Road Projects

Table of Content

Contents

Dedication

Abstract

Acknowledgement

Acronyms

List of tables

List of figures

CHAPTER ONE
INTRODUCTION
1.1 Background of the Study
1.2 Statement of the problem
1.3. Objective of the study
1.3.1 General Objective
1.3.2 Specific objectives
1.4 Research questions
1.5 Significance of the study
1.6 Scope and Limitation of the research
1.7 Structure of the research

CHAPTER TWO
LITERATURE REVIEW
2.1 Introduction
2.2 Background to the road construction project
2.3 Road Construction in Ethiopia
2.4 Road Construction in Addis Ababa
2.5 Performance of Addis Ababa City Road Projects
2.5.1 Productivity, Profitability and performance
2.6 Factors affecting the performance of road construction projects
2.7 Lean Construction
2.7.1 Lean construction principles
2.7.2 Traditional and Lean construction
2.7.3 Advantages of applying lean construction system
2.7.4 Barriers for lean construction implementation
2.7.5 Lean Construction Tools
2.8 Last Planner System
2.8.1 Initiation of Last planner system
2.8.2 Last planner system in Road construction
2.9 Research Gap

CHAPTER THREE
RESEARCH METHODOLOGY
3.1. Introduction
3.2 The Study Area
3.3 Study Design
3.4. Population and sampling techniques
3.4.1 Population of the study
3.4.2 Sampling
3.5 Method of data collection
3.5.1 Interview
3.5.2 Questioners
3.5.4 Focus group discussion
3.5.5 Document review
3.6. Procedure of data collection
3.7. Method of data analysis
3.7.1 The super decision model
3.8 How conceptual framework was developed
3.9 Data validation and reliability

CHAPTER FOUR
RESULTS AND DISCUSSIONS
4.1 Introduction
4.2 Current road construction management practice in Addis Ababa city
4.2.1 Observation result and discussion
4.2.2 Interview result and discussion
4.3 Last planner system implementation expected barriers
4.3.1 General information
4.3.2 Respondents profile
4.3.3 Assessment on last planner system practice on AA road construction projects
4.3.4 Analyzing last planner system implementation expected barriers using
SPSS
4.4 Modeling the last planner system implementation expected barriers
4.5 Benefits of last planner system implementation
4.6 Last planner system implementation conceptual framework
4.6.1 Conducting the focus group discussion
4.6.2 Conceptual framework discussion

CHAPTER FIVE
CONCLUSION AND RECOMMENDATION
5.1 Conclusions
5.2 Recommendations
5.2.1 Expectations from stakeholders
5.2.2 Expectations from the government
5.2.3 Recommendations for further study

Bibliography

Appendices

DEDICATION

This thesis is dedicated to all my parents.

My father, the late Mehari Limenih did not only raise and nurture me but also taxed himself dearly over the years for my education and intellectual development. Incidentally, he died on September 1, 2019. He did not live to see my highest academic achievement. May His souls rest in heaven!

My mother, Eseynesh Ayele has been a source of motivation and strength during moments of despair and discouragement. Her motherly care and support are incredible. May God grant her life and health.

ABSTRACT

Modern construction is characterized by its efficient utilization of construction resources to accomplish numerous construction activities without waste. But, Addis Ababa's Road construction projects fail to be executed on time, within the allocated budget, and with the desired quality. To solve this problem, a new management concept is introduced, namely lean construction. It is known to increase productivity and minimize waste. To realize this solution, last planner system (LPS) is used; it is one tool of lean construction. It is a person or group of people with the task to control the production unit. The main objective of this study is to assess usefulness of the last planner system implementation to advance the current construction process management in Addis Ababa city road projects. The research was conducted on selected asphalt road construction projects located in Addis Ababa city. To address the problems Questioners, observations, interviews, focus group discussion, and recently published journals were employed as a qualitative and quantitative data collection tools and analyzed using statistical package for the social science version 26 and super decision model version 3.2. The finding shows that; the construction management process adopted in all three sites is more or less similar they use a push planning system and critical path method to determine the duration following the master schedule but have no weekly work plan and lookahead schedule to forecast the coming week's duty. The LPS implementation expected barriers are also ranked from one to five: as Labor- related, internal working environment-related, stakeholders-related, exogenous related, and material related expected barriers respectively. The last planner system has many benefits as agreed by different scholar's those are time-related, Cost-related, claim-related, and quality-related benefits are the main benefits obtained through the LPS implementation and it is possible to conclude; LPS is useful for the road construction management system. The research is significant in creating awareness & understanding on the adoption of the lean construction tool (LPS) in sustainable construction, to improve knowledge and understanding of the implementation of LPS. Moreover, the LPS implementation conceptual framework was also developed based on the last planner system principles.

Keywords: Road construction projects, Lean construction, Last planner system

ACKNOWLEDGEMENT

I would like to convey my truthful gratitude to my Advisors Belachew Asteray (Ph.D.) and Abenezer Tariku (MSc) for their invaluable guidance and motivation throughout this research. . I acknowledge Addis Ababa City Road Authority staffs and stakeholders that have been always supportive and provide different relevant primary data's for the success of my research from the start to the final submission. . My gratitude also goes to all my friends especially Yonatan Haile (BSc) and Tamiru Mengist (MSc) for supporting and advising me starting from the beginning up to the final accomplishment of my thesis.

Finally, my heartful gratitude goes to my parents who have always been real supporters to achieve my educational goals. I would like to express my deepest gratitude to them for all their patience, love, and support.

ACRONYMS

Abbildung in dieser Leseprobe nicht enthalten

LIST OF TABLES

Table 2-1 Overall relative reasons for the lower performance of road construction projects. Source: (Almamlook et al., 2020)

Table 2-2 Definition of lean construction among different scholars. Source: (M S Bajjou et al., 2017)

Table 2-3 Comparative synthesis between traditional construction and Lean Construction. Source: (Saad et al., 2017a)

Table 2-4 Barriers to implementing lean construction in the KSA construction industry. Source: (Ola- nipekun, 2018)

Table 2-5 Challenges to LPS adoption in Egypt and Proposed Strategies. Source: (Aboseif & Khallaf, 2017)

Table 2-6 Benefits of last planner system adoption

Table 3-1 Interviewee personal data

Table 3-2 Questioner respondents

Table 3-3 Personal data of focus group discussion participants

Table 3-4 AHP fundamental scale. Source: (Saaty, 2016)

Table 3-5 AHP scale and their random consistency index. Source: (Saaty, 2016) - 53 - Table 4-1 Professional background of respondents

Table 4-2 Educational levels of the respondents

Table 4-3 Respondents' total year of professional experience

Table 4-4 Respondents Experience in the current position

Table 4-5 Current positions of respondents

Table 4-6 Assessment on last planner system Q1

Table 4-7 Assessment on Last planner system Q2

Table 4-8 Assessment on Last planner system practice Q3

Table 4-9 Assessment on Last planner system practice Q4

Table 4-10 Future plan to use LPS in road construction project Q5

Table 4-11 Top three internal working environment related expected barriers

Table 4-12 Top 3 Stakeholder related expected barriers

Table 4-13 Top 3 Material related expected barriers

Table 4-14 Top three labor-related expected barriers

Table 4-15 Top three external related expected barriers

Table 4-16 Benefits of last planner system implementation

Table 4-17 Sample look ahead planning sheet format

Table 4-18 Weekly work plan template

Table 4-19 PPC observation form

Table 4-20 Reason for incomplete tasks sample form

LIST OF FIGURES

Figure 2-1 Relationship of how all of these concepts relate to one another. Source: (Amanuel, 2016)

Figure 2-2 post-World War II Japan (Toyota motor company); Beginning of lean production. Source: (Onyango, 2016)

Figure 2-3 Lean construction wheel. Source: (Mohamed Saad Bajjou et al., 2018)

Figure 2-4 The five lean principles. Source: (Mohamed Saad Bajjou et al., 2018)

Figure 2-5 A push planning system. Source: (Saad et al., 2017a)

Figure 2-6 Last planner system diagram. Source: (El Samad et al., 2017)

Figure 2-7 Process of last planner system. Source: (El Samad et al., 2017)

Figure 3-1Addis Ababa City map. Source: (google map)

Figure 3-2 Research design flow chart

Figure 3-3 Steps to develop LPS implementation conceptual framework

Figure 4-1 Cronbach's alpha result

Figure 4-2 Questioners' response composition and rating

Figure 4-3 Clusters and their connection

Figure 4-4 Node comparison with respect to the internal working environment ...

Figure 4-5 Node comparison with respect to stakeholder related criteria

Figure 4-6 Node comparison with respect to material related expected barriers ...

Figure 4-7 Node comparisons with respect to labor-related expected barriers

Figure 4-8 Node comparisons with respect to exogenous-related expected barriers

Figure 4-9 Node comparison with respect to prioritizing LPS implementation expected barriers

Figure 4-10 Overall LPS implementation expected barriers synthesized model

Figure 4-11 Ranking the alternatives

Figure 4-12 Clusters and their connections

Figure 4-13 Node comparison with respect to time-related benefits

Figure 4-14 Node comparison with respect to quality-related benefits

Figure 4-15 Node comparison with respect to cost-related benefits

Figure 4-16 Node comparison with respect to claim related benefits

Figure 4-17 Node comparison with respect to prioritizing LPS implementation benefits.

Figure 4-18 Overall synthesized priorities of alternatives

Figure 4-19 Ranking LPS implementation benefit alternatives

Figure 4-20 LPS implementation conceptual framework

CHAPTER ONE

INTRODUCTION

1.1 Background of the Study

The construction industry is the means through which a society achieves its goals of urban and rural development. Still, it's getting decreasingly more complex partly because of the complexity of the construction process itself, and the large number of parties involved including Owners, users, designers, regulators, contractors, suppliers, and others.

The road transportation is a vital component of the economic and social development process, and absorbing a high amount of the national budget. This transportation system is responsible for the majority, if not all, of business, personal, and public economies. Road transport system of the developed or developing country represents a major part of that country's infrastructure significance both in terms of investment made in creating the highway network and its benefit on the country's economic development (Kassaye, 2016).

Generally, this chapter is an introductory part of the entire study. It gives some information about the environment and hypotheticals in which the research is conducted.. Construction industry, the true power of the national economy, through which the total of physical development is attained. It is an energetic component of a country's economy and has a significant effect on other industry sectors' efficiency and productivity. It is not possible to think of all-embracing investments like agriculture, manufacturing, fishery, etc. without road construction facilities (Tadewos & Patel, 2018). .. According to the researcher's construction industry is seen as a slowly progressing industry with numerous Problems. Specifically, the Road construction industry is often described as an industry with many problems and a lack of efficiency related to human resource performance. Several researchers have expressed concern about the continued decline in the performance of the construction industry and the increasing challenges facing the industry. To deal with this situation, some construction companies have adopted a Total Quality Management (TQM) system and others have tried rightsizing, restructuring, and other concepts to reverse the trend. The other recent way out to this problem is said to be in using the concept of lean construction (LC). .. In Ethiopia, like other developing countries the road construction industry is challenged by lower productivity performance challenges in executing construction projects. Especially, asphalt road projects are characterized by their low performance, inadequate capital base, limited material and equipment resources, lack of skilled laborers and managers, less introduction of new technologies, and limited participation of the private sector. By considering the situation, the adoption of a new way of thinking can be the solution for problems seen in the road construction industry. Evaluating the conditions and the environment of the construction industry from the lean concept perspective will be the prerequisite for implementing this new management concept. Lean thinking is a new way to manage the construction industry. Born in manufacturing, the goals demand a new way to coordinate action, one that applies to industries far removed from manufacturing. Implementation of lean construction only requires action to be shaped by in depth understanding of the goals and techniques . Lean construction is well known to cost reduction, increase profit or increase competitiveness, increase business opportunity and customer base, improve health and safety, improve quality, yield higher employee salaries, shorten production timescales, and increase customer satisfaction. With little attention on research of lean construction in Ethiopia, it remains a problem of non-standardization in waste elimination strategies thereby sub­optimizing waste management in Ethiopia Road construction projects. . Lean construction tools, in general, are designed to improve delivery systems and processes by reducing waste, boosting productivity, improving health and safety, and meeting client needs (Hannis-Ansah et al., 2016). The last planner system is one tool of lean construction; where it is a person or group of people with the task to control production unit. They are in charge for necessitating control of the workflow, verifying supply stream, design, and installation in all the production units. . Last planner system (LPS) is known to be the most developed practical use of Lean Construction. It focuses on minimizing the negative impacts of variability, uncertainties, buffers, making projects more predictable, creating reliable work plans, and convalescing collaborative planning. The lower performance of road construction projects is one of the basic problems which have a direct impact on the cost, time, and quality of the final product in the construction industry. This study aims to assess the usefulness of the Last Planner System implementation to advance the current construction management system in Addis Ababa Road projects.

1.2 Statement of the problem

This section of the research explains the driving forces that enable the researcher to study on the selected topic and area. The initiation for this research is mainly due to self-observation and different journals stating the low performance of asphalt road construction projects in Addis Ababa city.

For a while, construction companies over the globe have been working to improve their productivity, flexibility, increase their overall usefulness, and reduce response time to act upon varying customer demands. Many construction management concepts are emerging from different ages in the construction industry. The lean concept (LC) is a recent management concept. LC is excellent in managing the construction process, which increases productivity and eliminates waste.

In Ethiopia, there are conventional practices in leading, managing, and controlling road construction projects through the life cycle that bring about such inefficiencies and information loss, lower productivity, wasted time, inconsistencies in the work progress, and rework, are the foremost gaps in the existent practices (Kassa, 2020).

As Tesfa, (2016) studied almost 80% of the road construction projects were completed beyond their planned completion time out of all the asphalt road construction projects that were completed from 2008 to 2013, Therefore, the researcher concluded that time overrun for asphalt road construction projects in Addis Ababa city administration is common and the root cause of this problem is the lower performance of the projects. So, the decline of productivity in Addis Ababa city road construction projects is one of the greatest and most severe problems that the road construction project faces. As the historical figure of completed road construction projects shows, no projects were completed within the estimated cost, time, and within the desired quality. And also, no improvement mechanisms have been adopted to overcome on those problems (Tadewos & Patel, 2018).

Substantial cost over-run, loss of quality, and delay of the project could occur as the result of insufficient data transfer from design, construction to road operation and maintenance, on such inefficiencies as road projects workforce productivity loss, road projects workforce rework, and road project information verification needs additional workforce also additional existing challenges faced.

As a result, lean construction is one of the major change efforts for the construction industry, and little effort is made to improve project planning, scheduling, and management problems using these concepts. This research analyzes the lean concept using the last planner system as a tool to identify and prioritize its benefits and expected barriers in Addis Ababa city road construction projects. This study also contributes to minimize the gap in the literature and thereby establishes the basis for the understanding of some aspects of the usefulness of adopting the last planner system to enhance the construction process management. Furthermore, it also indicates the expected barriers and benefits for the implementation of the last planner system in Addis Ababa Road construction projects.

1.3. Objective of the study

1.3.1 General Objective

The general objective of this study is to assess usefulness of the last planner system implementation to advance the current construction process management system in Addis Ababa city road projects.

1.3.2 Specific objectives

- To examine the current construction process management practice in Addis Ababa city road projects.
- To prioritize the expected barriers of the last planner system implementation in Addis Ababa Road construction projects by using the super decision Model.
- To prioritize last planner system implementation benefits to Addis Ababa Road construction projects using the super decision model.
- To develop a conceptual framework for the last planner system implementation to enhance the current construction management system in Addis Ababa city road construction projects.

1.4 Research questions

- What looks like the current road construction process management system of Addis Ababa Road projects?
- What are the expected barriers faced to implement the last planner system in the Addis Ababa city road construction project?
- What are the benefits obtained by implementing the last planner system in the Addis Ababa city road construction project?
- Is there a need to develop the last planner system implementation conceptual framework for Addis Ababa city road construction projects?

1.5 Significance of the study

There are some studies about the usefulness of lean construction tool (Last planner System) in the construction industry, most of the previous studies have been performed in developed countries in which technological advancement in the construction sector is more advanced than in developing countries such as Ethiopia. Hence, this study contributes to preexisting knowledge of effectively implementing new management concepts like lean. Effectively applying or introducing new concepts especially in Ethiopia's construction industry is a problem in developing the science of construction. Assessing the usefulness of the last planner system implementation is helping to identify the benefits and expected barriers of LPS implementation and to achieve the change that the road construction industry needs.

The concept of lean construction tool (last planner system) has been established in various studies. However, the understanding of the usefulness of LPS implementation issues in the Addis Ababa city road construction project needs to be more emphasized. Therefore, the research intended to provide; Awareness and consideration of the benefits and expected barriers of the lean construction tool (last planner system) in sustainable construction, improved knowledge and understanding on the implementation of last planner system in Addis Ababa city road construction projects, and development of a conceptual framework for assessing last planner system implementation efforts and the advantages that can be derived from its implementation. It is expected that the developed framework is beneficial to Addis Ababa city road authority because it enables the organization to manage, measure, and evaluate the benefits arising from the use of last planner system techniques as it improves productivity and minimizes wastage. The outcome of this research provides a knowledge base for companies intending to implement lean construction tools like the last planner system. It would also allow companies to evaluate the strengths and weaknesses of their last planner system implementation processes based on the impact assessment results and also the company can easily measure the performance of the labor using percent plan completed (PPC). Also, the research provides a benefit to the road construction industry as it minimizes waste and increases productivity.

1.6 Scope and Limitation of the research

The research cannot pretend to address everything within the domain of the study. As such, it is necessary to state the boundaries of knowledge and basic assumptions underlying the research. This study is conducted on Addis Ababa city road construction projects. Among entities that are involved in road construction projects, ongoing projects located in Addis Ababa, Ethiopia are exposed to a problem of lower productivity performance, which enables the contracting companies failed to complete on time, within the allocated budget, and with the best quality. The study also focuses only on ongoing asphalt road projects in Addis Ababa city. This research is conducted by using only one of the powerful lean tool called the last planner system, among the rest. Unavailability of sufficient documented information in the field of the study, lack of willingness of the concerned bodies, and bureaucracy of different organizations including this university are also the research limitations.

1.7 Structure of the research

This study contains five main parts and two supplementary parts namely introduction, Literature review, research methodology, results and discussions, and conclusion and recommendation; Bibliography and appendices are supplementary parts. The five main parts are introduced below.

Chapter 1: Provides an introduction of the theme probed in this study. The main purpose of this chapter is to explain about the background of the study, statement of the problem, aims of the study, limitation, scope of the study, the significance of the study, and the research outline.

Chapter 2: Provides the literature review about the main subjects of the thesis; benefits and hoped walls for the renouncement of LPS and to Supplying practical suggestions and recommendations to enhance the performance of Addis Ababa town road construction systems and to minimize the construction wastes in a road system. In addition, this chapter provides a theoretical foundation with the wording of some propositions, which are the cornerstone for the methodology examination.

Chapter 3: This chapter is the methodology of the study and it provides the plan of the examination and it talks about how the examination was executed and data were gathered. In other words, this section explains the examination paradigm, approaches embraced, strategies followed, data collection manners, and data analysis manners.

Chapter 4: This chapter is about results and discussions and it furnished the analysis of primary and secondary data using different software to achieve the examination ends. And the results are also carried and described in detail. In addition, these results are used in this section to see how they help confirm or reject the suppositions. On the other hand, this chapter also provides a critical evaluation of this work including the limitations of the examination.

Chapter 5: This chapter contains conclusions and recommendations which summarizes the main issues of the examination work and it provides an overview of the main findings. It also concludes if the game met the proposed ends and how this thesis was useful to confirm or reject the supposition. Moreover, it also contains suggestions for road construction assiduity.

CHAPTER TWO

2. LITERATURE REVIEW

2.1 Introduction

This chapter provides a background to the study by reviewing comprehensive recently published journals related to the study area and the purpose of this section is to provide the required theories to understand about Lean construction, last planner system, road construction performance, and benefits obtained by implementing last planner system. It explains the problem that is going to be investigated and how that particular problem is going to be assessed. The target is to get knowledge and ideas about the research title and it also shows the possible strengths and weaknesses from different countries and different researchers. To answer the research questions, it is mandatory to find out necessary theoretical and empirical previous researches on the problems. Therefore, it is necessary to provide theoretical information about lean construction and the last planner system. The chapter also serves as a reference from past studies and historical background on the usefulness of adopting the last planner system in the construction process of Addis Ababa Road projects.

2.2 Background to the road construction project

Road construction projects are means through which development strategies are achieved. Development strategies that are fulfilled through successful road construction projects intend to improve the accessibility of rural areas; lower costs associated with transport maintenance and open more areas for development activities. The road projects, involving a large amount of cost, also contribute to the total economy through job creation and in a ripple effect to other business activities. Several efforts to develop the road sector have been made to ensure projects' achievement. Phased Road Sector Development Programs which provide a coordinated framework for intervention along with policy, institutional and regulatory reforms have been launched. These programs are aimed at developing efficient and self-sustaining construction industry and improving the management of the road (Weldegebriel, 2018).

2.3 Road Construction in Ethiopia

Historic chronicles of the 17th and 18th centuries show that there were some small roads, trails, and footpaths, in addition to the traditional shoulder porterage, animals like mules, donkeys, and horses and camels were used as a means of transportation in Ethiopia.

In the 18th century, specifically during the reign of Emperor Tewodros, although the technology was primitive it was believed that planned road construction efforts were made. It is also believed that Emperor Yohannnes IV, who succeeded Tewodros, was engaged in road building. Nevertheless, due to the danger of invasion by Egyptians, Derbush and Turkish the Emperor was not able to achieve his desires. It was before the second Italian occupation i.e., between the years 1896 and 1936 that a great success was made in road construction. King Menilik was said to be an effective road builder participating himself in the construction. In 1903 the road from Eritrea to Addis Ababa and the road from Addis to Addis Alem was built. In addition, it was during this time that the first Asphalt roads appeared in Addis. At the time of the Italian occupation, roads were built by them and they were established to meet the requirements of the Military control rather than to promote the overall development of the country's economy. In addition, the roads lacked most of the modern location, design and construction feature desirable for present-day high-speed traffic. The roads and trails built and improved during the 5 years of Italian occupation were about 6000km. Almost 2500 km of them were given a single asphalt surface treatment, drainage structures were usually of stone masonry and at least three tunnels were built. But, when Ethiopia regained its independence, the Italians in their fleeing attempt almost undid what they created by blasting bridges and dynamiting roads. From the time the Italian packed off home to the eventual creation of the Imperial Highway authority (1941 to 1951) road construction or maintenance activity was almost subsided for a stagnation period of one decade because of lack of funds, equipment, and expertise (Kassaye, 2016).

To remove bureaucratic impediments, regional and rural road authorities were separated from the Ethiopian Road Authority (ERA). Each authority was then made to take on the part of a client of road works. Special attention was also paid to the private sector participation, via strengthening Contractors' competitive capacity to undertake construction and maintenance works. The midterm and final reviews of the phased road sector development plans show that despite the improvement seen in performance and productivity within the sector, there still remain problems of delay and cost overrun of all road construction projects. It is also recognized that there is a need for additional strengthening of institutional capacity, adoption of new construction technologies and modern project management principles, and additional regulatory reforms to maximize the efficiency of the Ethiopian road construction industry (Weldegebriel, 2018).

2.4 Road Construction in Addis Ababa

Road construction is the main contributor to the country's economic development that connects one part to the other part. Addis Ababa road network plays a great role in the economy of the city and country as well. The road constructions are predictable to complete on time and within the estimated budget and open for traffic, but all of the road projects are always faced with time overrun and over budget. Different studies in the area shows that as delay and cost overruns are a common phenomenon and it affects road projects greatly. Financial problems, improper planning, land acquisition and construction delay, design changes, fewer materials and equipment supply by contractors, lower labor productivity, and incomplete design are the main sources of delay and cost overrun respectively. So, once identified the main causes it is necessary to give solutions to complete the projects on time and estimated cost (Tadewos & Patel, 2018). . It is well known that most road construction projects in Ethiopia and Addis Ababa city are exposed to time and cost overrun or both. It becomes very problematic to complete the road construction projects in the allocated cost and time (Tesfa, 2016).

2.5 Performance of Addis Ababa City Road Projects

The important measures necessary to be included in the road construction sector beyond the widely implemented performance measures (time, cost, quality, safety, productivity and profitability) were found to be technology adaptability, effective utilization of materials, designer and supervisor performances. The performance measurement methods, traditional financial accounting and balanced scorecard were found to be the highest Practiced Performance Methods. The performance factors that were ranked critical, from the consultant side were found to be, design change, absence of regular site inspection and lack of effective communication system. From the client-side, inadequate site investigation, poor material management and poor cost management were found to be the utmost performance factors. Similarly, from the contractor's side, cost management problems and low productivity, inadequate site investigation, and design change were found to be the highest performance factors. Depending on the nature of project-based organizations and performance factors' tendency to cause construction problems, the Performance measurement framework was proposed to be considered by the road construction sector. The framework comprises organizational Goals, strategic objectives, performance dimensions, organization and project drivers, enablers, performance factors and results. To implement the framework Strategic objectives could be developed from either goal or external stakeholder's needs. This helps to develop project and organization driver measures and fix the performance dimension as a base for the end result. Though, Project enabler measures could be derived from major stakeholder's (client, consultant and contractor) organization and project drivers and act as input to the end result. If there is any deviation in performance it can be noticed through enablers and results. Existing performance problems can also serve as a feedback tool for stakeholders' performance in the project and organizational level. It can also use to develop issue-based strategy and project and organization driver measures (Ayele, 2019; Bayu, 2020). . In Ethiopia, particularly in Addis Ababa, there are many road projects constructed, under construction, and planned to be constructed. But, a very common problem that is affecting almost all road construction projects in the city is the failure to meet the stated/planned completion period (delay). And therefore, this chronic problem is repeatedly happening in almost all road projects of Addis Ababa city administration and we can assume a list of factors to affect the on-time accomplishment of projects. Almost 80% of the projects were completed beyond their planned completion period out of the asphalt road construction projects which were completed from 2008 to 2013. Therefore, the researcher concluded that time overrun for asphalt road construction projects in Addis Ababa city administration is common. Causes of delay are related to both the owners, contractors, consultants, and slightly with external factors. It should be noted that owners, contractors, consultants, and even the economy of the city and the country are all affected by the problem of untimely delivery of these projects (Tesfa, 2016) . . Project managers planning responsibility, availability of project funds, availability and adequacy project equipment's, advancement of project equipment's, empowerment orientation and team orientation has significantly affected the performance of road construction projects administered by AACRA. To execute projects more efficiently within stipulated budgets and time and per quality specifications, the study recommendations AACRA to provide pieces of training on financial management, a project plan should be developed by the competent project manager and be discussed by all stakeholders before the final draft is completed and implemented, introducing new management concepts, improve laborer's productivity this reduces many change orders during the construction phase that normally results to high-cost overruns, to implement the currently available technologies regarding equipment, team up with all the stakeholders elaborate in the road projects, so that they can take over the management and aid in running the projects and practitioners devote more effort and resources towards making their organization more team and empowerment oriented (Bayu, 2020)(Minalu, 2014).

2.5.1 Productivity, Profitability and performance

The difference between those three concepts is that profitability takes into account monetary effects, while productivity related to a real process that takes place among purely physical phenomena. Like productivity, profitability is also seen as a relationship between the output and the input, but the relationship is monetary. Productivity is considered more appropriate than profitability as a measure for monitoring manufacturing excellence since profits are influenced by many factors over the short term that can give a misleading indication of long-term success.

Performance is another perception that is often confused with productivity. Whereas productivity is impartially specific concept related to the ratio between output quantity (i.e., produced products) and input quantity (i.e., resources that are consumed in the operation process), performance is a broad concept that covers both the economic and operational aspects of an industry. Performance refers to excellence and includes profitability and productivity among other non-cost factors, such as quality, speed, delivery and flexibility (Amanuel, 2016; Emagnu, 2018).

Abbildung in dieser Leseprobe nicht enthalten

Figure 2-1 Relationship of how all of these concepts relate to one another. Source: (Amanuel, 2016)

2.6 Factors affecting the performance of road construction projects

The reasons for the lower performance of road construction projects were identified especially focusing on selected African countries.

According to a study in Tanzania, it's found out that total cost and time overrun rates on average be 44% and 26% respectively by considering seven projects. The study further identified that among other factors the average contribution of inadequate design and the extent to which inadequate design to be 26% and 32%s respectively contributes, as a percentage, to cost and time overruns were 61% and 85% respectively (Simon, 2015). . Nigerian construction industry, it is also still struggling with a lot of intrinsic challenges, ranging from inadequate technical and managerial know-how to insufficient financial, material and equipment capital base. A study on evaluation of management challenges facing the Nigerian construction industry also revealed that time; cost, quality, and safety remain the top management challenges facing construction managers in Nigeria (Ugwu & Attah, 2016).

According to a study conducted in Uganda, Some of the major findings from this study include weak procurement rules which lead to awarding road projects to incompetent contractors; contractor monitoring being handled by unqualified, incompetent and inexperienced professionals; lack of contractors and contract supervisors appraisal system; delay of contractors payments which affects timelines in services delivery; lack of a strong internal project monitoring and evaluation mechanism at the Uganda National Roads Agency (Byaruhanga & Basheka, 2017).

A study conducted in the Sudan construction industry shows that Sudan is suffering from several problems and challenges such as poor performance of construction projects. As per the study, the most important factors influencing project performance were project team leader experience, planning effort, adequacy of design and specification, cost progress monitoring, and leadership skill of leader (Akinradewo et al., 2020).

The case in Kenya is also not different from other most African countries. The construction industry is facing lots of challenges such as the expenditure exceeding the budget, delay to complete the project in time, building defects, and over-reliance on foreign workers. Most construction projects especially road infrastructure in Kenya are exposed to extreme cost escalation to the extent that it calls not only for extra funding but also specialized expertise hence leading to technical and project managerial conflicts between project parties (Viera Valencia & Garcia Giraldo, 2019).

According to key findings in another study conducted in Kenya showed that capital availability, managerial skills, organizational culture, and technical skills influenced the performance of road projects. The key challenges that faced the implementation of road projects were inclement weather conditions, inadequately skilled laborers, inadequate equipment, delayed payments, unforeseen ground conditions, and political interference. The study recommends that the county government should hire experienced and competent road contractors to implement road projects and road contractors should plan for unforeseen weather changes that might impact negatively road projects implementation. Moreover, it's recommended that the government should strengthen capacity and capability to boost professionalism and performance of road contractors (Seboru et al., 2016).

From the journals assessed above, the major factors affecting the performance of road construction projects include: slow decision making and bureaucracy in client organization, inadequate planning and scheduling, rain, availability of personnel with a high experience and qualifications, quality of equipment and raw materials in project, conformance to specification, planned time for project construction, lack of a strong internal project monitoring and evaluation mechanism, availability of resources as planned through project duration, average delay in payment from owner to contractor, information coordination between client and project parties, team leader experience, planning effort, adequacy of design and specification, cost progress monitoring, delays because of borders/roads closure leading to materials shortage, unavailability of resources, low level of project leadership skills, escalation of material prices, poor quality of available equipment and raw materials, learning and exploitation, client satisfaction, stakeholder objectives, operational assurance, and user satisfaction.

Table 2-1 Overall relative reasons for the lower performance of road construction projects. Source: (Almamlook et al., 2020)

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In the case of Addis Ababa, as Bayu, (2020) approves that project manager's planning responsibility, project managers interpersonal skill, project manager's experience, project managers working integrity, and project managers efficiency were the most important attributes of project managers competency related factors that influenced project cost, time and quality performance in Addis Ababa city road construction projects.

2.7 Lean Construction

Lean construction (LC) philosophy doesn't have a single definition in the scientific references, it's still evolving as the academic research, in particular doctoral research, feeds this concept(M S Bajjou et al., 2017). The most common definitions used are shown in table 2. 2.

Table 2-2 Definition of lean construction among different scholars. Source: (M S Bajjou et al., 2017)

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The origins of the lean concept emerge from the studies from the Japanese automobile industry called Toyota which study was a critic to the American auto industry that utilized a system of mass production. As mass-production focused largely on quantity, this approach exhibited defects, high inventories, and low variety. In mass production, the work was done by unskilled or semiskilled workers making products as had been designed. The flow of the system continued even when there was a possibility of defects carried on since these would be later rectified in the reworks sector. Therefore, wastage was high arising due to defected pieces discarded, time to do reworks, and effort spent on non-value-adding tasks. Other problems that were noted to be in the mass production included; lack of coordination and communication between different divisions, quality issues only realized at the end of production, impossible designs or design changes that necessitated reworks. From this analysis, a better way to do production was derived and introduced called the Toyota Production System (TPS) (Onyango, 2016) .

The Lean Construction philosophy emerged as an alternative to the Traditional Production System, production ideology most adopted nowadays. Based on this system, a production process should be understood as the result of many conversions required to obtain the final product. In the civil construction's case, the conversion could be understood as being material or labor transformations, and the final product refers to the building itself (Ansah et al., 2016).

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Figure 2-2 post-World War II Japan (Toyota motor company); Beginning of lean production. Source: (Onyango, 2016)

Figure 2.2 clearly shows how Lean production ideology has emerged in Toyota motor company. The reasons are the availability of limited natural resources, limited spaces to store the products, mass production practice without any demand, lower demands of the customers, and additional factors that encourage them to adopt the lean concept. And they develop just in time delivery of their products with a high quality to their customers.

The lean production is a sophisticated, efficient philosophy that gained attention after automobile manufacturer Toyota implemented the method after World War

II. This method, Toyota Production System, became renowned due to its creator Engineer Ohno. Engineer Ohno developed the foundation for the production system that allowed for greater customer satisfaction, fewer inventories, and less waste. In the 1990s, a lean movement began as companies started to adopt some of the strategies of Ohno's system, and in turn, the modern concept of lean production arose (Salem et al., 2016).

Lean Construction is simply an attempt to apply lean principles that originate from TPS to construction, aiming at managing and improving construction processes, with minimum cost and maximum value by considering customer needs. Unlike the current practice, lean construction involves on production management principles. The result is an original project delivery project that can be applied to any kind of construction but is particularly suited for complex, uncertain, and quick projects. Lean Construction started from a mix of academics and consultants working not from industry; to translate lean concepts to the construction industry. Over the past 10 years, a growing number of companies have implemented lean construction practices in an attempt to enhance performance in construction projects. Most companies, and also some researchers, have reported satisfactory results from their implementation (Mowade & Shelar, 2017). The lean Construction gives valuable techniques to manage construction at improved workflows and nominal waste generation. Emergence of the lean construction concept is understood as a current approach that can be used to produce best practices because it was viewed as an effort to bring the construction industry towards a more optimum productivity level with the efficient usage of resources as well as to produce the utmost value. Lean construction is understood as a new paradigm for project management, thereby challenging the traditional thinking about construction and project management (Adegbembo et al., 2016).

For the current global economy, Lean Construction has become an effective way to design construction systems, which aims at minimizing all forms of waste and creating the maximum of value for the customer (Mohamed Saad Bajjou et al., 2018).

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2.7.1 Lean construction principles

Lean principles were formulated from the Japanese automobile industry. These underlying principles in lean, referred to as the Toyota Production System (TPS), aims to reduce wastages, achieve clients' expected value and lead to continuous improvement in the deliverables in projects. From the lean principles, an adaptation was developed for the construction industry. Since it was based on the original lean principles, the objectives were therefore built from those very lean principles (Onyango, 2016) .

The five principles of Lean as described by (Saad et al., 2017b): .

1. Create value: is essential to identify the value requested by the client and provide it to obtain his satisfaction.
2. Map the value stream: Mapping the chain of value of the construction process facilitates the identification of waste and its elimination by forcing collaboration among stakeholders.
3. Create the flow: it is necessary to think of its operations in an ideal flow passing through successive steps creating value for the customer.
4. Pull (rather than push): much of the effort is achieved by maintaining the flow, driven by what is really demanded by the customer.
5. Seek perfection: even if it should never be achieved; Continuous improvement is the main key of this principle and also depends on the implementation of the appropriate techniques and process. The Implementation of the Lean Construction concept involves the use of the most adapted techniques and tools of lean philosophy and which fit with specificities of the construction industry.

The principles of Lean thinking emphasize delivering value to the client while continuously improving the production process to eliminate non-value adding activities and any interruption to the flow of value, which are collectively considered as waste (Bashir et al., 2017).

The five lean principles as salunkhe stated

I. Value specification: Precisely specify what creates value from the client's perspective.
II. Value stream identification: Clearly identify all the steps in the processes (value stream) that deliver exactly what the customer values and remove everything that does not add value to the customer.
III. Flow: Take action that ensures Continuous-flow in the value stream.
IV. Pull: This means to produce only what the customer wants just in time, and
V. Perfection: Always strive for perfection by delivering what the customer wants and expects through a continuous removal of waste. Through process improvement to deal with the challenges in the construction (Salunkhe, 2018).

Lean philosophy provides a concrete basis not only for economic, but also social, and environmental purposes in sustainable construction by improving the delivery processes of green facilities. The key impacts of using Lean construction methods for the purpose of sustainability are categorized as follows:

- Economic perspective: possible upfront cost reduction, resource savings, operating cost reduction, and high-performance capability.
- Social perspective: workplace safety, occupant health, community wellbeing, loyalty among stakeholders, and external image improvement.
- Environmental perspective: reduced resource depletion, pollution prevention by eliminating waste, and resource preservation (Bae & Kim, 2017).

The concept of lean construction has been observed as a useful means of performance improvement in developed and emerging countries. There is some level of awareness up among professionals about lean construction even though lean construction is not yet practiced in the Ethiopian construction industry. The potential and benefits expected from the implementation of lean construction are greater productivity, improved sustainability/ waste reduction, greater customer satisfaction, and reduced project schedule and high-quality construction. In addition, the most influential expected barriers to implementing lean construction are lack of knowledge, lack of industry support, lack of sufficient support among the project team, employee resistance, and lack of standards (Ayalew et al., 2018).

Several Lean Construction practices such as the correlation between scheduled tasks and the ability of the staff working on-site, choosing of working methods in compliance with safety requirements, the incorporation of visual tools, and the Simplification of workflow could minimize the risk of accidents and promote the worker safety through minimizing hazards, motivating people involved in the planning phase and preventing human errors (Saad et al., 2017b).

Several studies have identified lean construction practices as a strategy for minimizing the overall cost & duration of a project by eliminating non-value-adding activities & obstacles to a reliable workflow. Although several studies suggest that the Japanese lean production system exposed workers to poor safety conditions and excessive stress in the manufacturing sector, advocates of lean construction argue that the application of lean construction tools could minimize accidents on construction sites (Bashir et al., 2017).

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Figure 2-4 The five lean principles. Source: (Mohamed Saad Bajjou et al., 2018)

2.7.2 Traditional and Lean construction

In the faster, construction projects, it is impossible to manage the project through conventional ways. It has been observed most of the time productivity of the construction depleting and leads to rework and produces many wastages such as overproduction, inventory, unnecessary transportation, workers displacements, overprocessing, defect, waiting of materials, unused employee creativity, work accident, etc. Practical ideas and techniques need to be used in construction that help projects teams to deal with wastages in construction with the use of optimum resources (human, material, machinery and information and this can be achieved by using lean construction principles and techniques (Salunkhe, 2018).

The growing context of globalization permanently increases pressure on the construction companies to improve their performances to resist the constraints of competitiveness in the international market. It has become ineluctable to look for introducing a new alternative capable of bringing creative improvement to the traditional production system (Saad et al., 2017a).

Numerous studies have approved that in the traditional planning model more than 50% of scheduled tasks are not carried out on time. In most of the time, a single entity (project manager) dictates 'what to do' and 'when.' to the rest of the stakeholders in the project. Indeed, the project manager realizes the general plan “Master Schedule” based on the project information and the targeted objectives, leading to a temporal state of what “Should” be done without taking into account of neither the fundamental reality of the site of construction nor the ability of companies to fulfill their missions.

“Traditional,” push planning system is illustrated in the figure below (Saad et al.,

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The head followed the outdated approach to construction management. Scheduling was done at the head office before the project execution and it was pushed to the site teams to follow as a single plan during the whole project. There was no any knowledge and employment of the LPS. Traditional planning included the following steps: .

1. Master Plan: It is the form of Gantt Charts or a timeline was created for each of the blocks and handed over to the senior site engineer. In a block, the senior site engineer was head under whom there were many junior engineers. The junior engineers were responsible for the construction of 4 plots whose design was provided to them in advance.
2. Push Planning: especially for material Requirement. Each of the material requirements had to be given by fresh engineers to the senior site engineer who communicated the same to the project head. The price was made for the whole month according to the drawings and a copy of the same was provided to the project head who was responsible for procurement of the material. Therefore, push planning was used where the end item quantity needed was procured regardless of its demand on site.
3. Storage of the materials: There was no proper residence for storage of the material and half of the materials lie on the site itself mostly in the stagnant water from curing. There was a small shed where the material which was not currently in use was put and that too in a haphazard manner. And also, some of the material even got expired there.
4. Monthly Work plan: A monthly plan was made in the office by the assistant of project coordinator and it was provided to the site engineers as a target. The targets were hardly met due to many difficulties and poor planning and coordination(Walia & Suri, 2017).

By adopting the lean construction principles, construction industry can benefit from a very wide margin to improve their organizational management system especially on the level of these three fields: Creating value and eliminating waste, Planning and mutual coordination and Site organization. Indeed, the lean construction tools such as (Last planner system, Value Stream Mapping, Just-in-time, Kanban, 5S Visual management) have been proposed as solutions to improve the current situation of the traditional production system of construction. The lean construction tools contribution can be summarized as follows:

Value Stream Mapping (VSM): it allows to graphically visualize most sources of waste (Over-Production, Unnecessary transportation, Inventory, displacements, waiting). Therefore, an immediate action plan can be elaborated to optimize the flow, remove the steps not really necessary, and sustain the culture of continuous improvement.

Just-in-Time: it facilitates the transfer from a push strategy to a pull strategy using kanban cards which allow reducing the amount of inventory.

Last Planner System (LPS): it is an effective solution that could be considered as the substitute to the traditional planning system (A Push Planning System). It aims at advertising people's involvement and reducing wastes that are caused by ineffective tasks synchronization.

5S: 5S enhances the organization of the construction site by keeping each material in its place and removing all unnecessary components.

Visual management: it makes the construction process transparent, simple and safe for all stakeholders on-site through digital billboards, signs of security and graphical dashboards (Saad et al., 2017a).

Table 2-3 Comparative synthesis between traditional construction and Lean Construction. Source: (Saad et al., 2017a)

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2.7.3 Advantages of applying lean construction system

Most road construction projects are characterized by the non-respect of the triptych (Cost, Time, Quality) and a high accident rate compared to other sectors. Lean construction (LC) is a new production philosophy that has the potential of bringing innovative improvements in the construction sector. Lean construction is a systemic approach to fulfill customer expectations by maximizing added value and reducing all forms of unnecessary waste. Based on international standards. Many researchers have confirmed the usefulness of the LC concept for projects of construction. The main advantage is that companies could reduce the costs invested in construction projects by using fewer resources and reducing waste on production sites. In addition, having proper project planning, it would shorten the duration of the construction project (M S Bajjou et al., 2017).

2.7.4 Barriers for lean construction implementation

As the scholar identify and rank barriers of lean construction implementation in the Ethiopian construction industry; lack of knowledge and skill, lack of industry support/ understanding of lean and lack of sufficient support across the project team, lack of standards are the top five most influential barriers to implement lean construction in the Ethiopian construction industry (Ayalew et al., 2018) .

The barriers to the realization the full potential of LPS, including the involvement of many subcontractors and people's commitment and attitude to time (AlSehaimi, 2017).

Table 2-4 Barriers to implementing lean construction in the KSA construction industry. Source: (Ola- nipekun, 2018)

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2.7.5 Lean Construction Tools

Lean Construction philosophy was emerged to assist overcome the challenges in optimizing the productive processes of companies. As an effort to quantify the application degree of Lean philosophy in the civil construction companies, several measurements tools were created (Lucena & Mori, 2018). . Lean construction tools have certain features like housekeeping, workers empowerment, and error-proofing which could be used to reduce accidents caused by trips, slips, congestion, excessive stress and site hazards. Lean construction tools could also help to address factors such as poor work methods, physical and mental inability of workers, poor communication, and poor planning (Bashir et al., 2017).

Lean Construction that the lean construction tools can provide a solid basis for improvement to the traditional production system (Saad et al., 2017a) . .

In order to confirm that every aspect of LC tool is captured concerning the lean tool's suitability, the study extended the existing LC tools. The recognized lean tools were evaluated through the interview and the findings confirmed 30 lean tools including Last Planner System (LPS), Concurrent Engineering and daily huddle meetings as being the most operative lean-delay control tools for the delay sources mitigation. The result from this study would serve as an implementation guideline for lean construction projects, thus, offer an understanding of the specific lean tools to adopt in projects. Construction managers should be able to use these tools to create a realistic and sensible lean application guide.(Ansah et al., 2016). . Based on an analysis of the scientific research conducted in several countries, we found that the most appropriate LC for the construction industry are as follows: the last planner system (LPS), visual management (VM), 5S, value stream mapping (VSM), building information modeling (BIM), prefabrication, analysis of roots causes (5 Why, the Ishikawa diagram, PDCA.. ), Just in Time, Poka-Yoke. The lean construction tools (Prefabrication, value stream mapping, Poka Yoke, visual management & 5S have a direct impact in promoting the main factors of sustainable development (M S Bajjou et al., 2017). Over the last decade, a number of effective lean production approaches and technologies for managing construction projects have been developed. Some are

procedural, while others are conceptual, and yet others are coded. Furthermore, while some of these technologies are straightforward, others are more complicated, such as the last planner system (LPS). In the hands of managers inspired by lean project conceptualization and management, this diverse combination of tools is extremely effective.(Ansah et al., 2016). . According to Ansah et al., (2016) some lists of lean construction tools are: - .

Last planner system: - The last planner is a person or group of people with the task to control the production unit. They are responsible for necessitating control of workflow, verify supply stream, design, and installation in all the production units.

5S: - 5S is a lean tool developed from five Japanese words: Seiso (shine), Seiton (straighten), Seiri (sort), Seiketsu (standardize) and Shitsuke (sustain), as a foundation for continuous improvement (Bashir et al., 2017).

- Seiri (Sort): Sort commonly used equipment/materials on the building site by separating them from less regularly used parts; as a result, greater accessibility will be achievable since essential materials/equipment will be easier to find, reducing condensation and perhaps improving work safety.
- Seiton (Set in order): Arranging each element in its proper location helps to decrease waste connected with employees' movements in search of construction supplies, as well as hazardous displacement that could endanger the workers' safety.
- Seiso (Shine): Keep the workplace as clean as possible to reduce waste related to dirtiness which leads to an increase of the employees' satisfaction.
- Seiketsu (Standardize): Using clear and straightforward procedures, standardize and disseminate the three initial S.
- Shitsuke (Sustain): Try to integrate the 5 S into the organization's culture through training, controls, and promotions (Saad et al., 2017b).

Concurrent Engineering: - This methodology involves the various tasks parallelly executed by multi-disciplinary teams to optimize engineering cycles of products for efficiency, quality, and functionality.

Check sheet: - Defect Concentration Diagram is another name for it. This is a well- structured form for gathering and analyzing information. It's a generic tool that can be used for a range of tasks, such as observing and collecting data on the frequency of patterns of problems, events, flaws, and causes, among other things..

Construction process analysis: -Process charts and top-view flow charts are prevalent in process analysis approaches, and this actualizes them. These diagrams and charts use standardized symbols to efficiently illustrate process flow and allow for quick identification of problem areas. Operation, Storage, Transportation, Volume Inspection, Delay, and Quality Inspection are the six symbols on the chart. Every phase or advancement of a building project is documented in the process diagram. It also keeps track of the flow of information between units, sections, and departments. . Six sigma's: - it is Sets of tools and techniques for improving quality through identification and removal of defects and reduction of variability in processes. Six Sigma can achieve a process quality of 99.99966% that is free from defects. Continuous flow: - This means to constantly provide or process and produce through a progressive system of uninterrupted steps in the process. . Kanban (Pull System): - This is a Japanese word that literally means “billboard or signboard”. It is an information control process that regulates the movements or flow of resources so that parts and supplies are ordered and released as they are needed. Kaizen: - Kaizen is Japanese business philosophy for continuous improvement. This is an approach that seeks to improve quality and efficiency through the elimination of waste from the value stream. . Poka - Yoke (Error Proofing): - This is a mechanism designed to detect and prevent errors in processes to achieve zero defects. Poka-yoke is a Japanese word meaning error-proofing. It is one of a lean tool that involves all forms of duties and devices that could prevent an error from occurring. It is a way of avoiding inadvertent errors in a way that is simple and cost-effective. It is a concept that deals with basically what people can do to avoid errors in the workplace (Bashir et al., 2017).

Value Management: - Through the use of visual signals, this is an information communication strategy that is used to improve process efficiency and clarity.. PDCA(Plan-Do-Check-Act): - This is an iterative approach for improvements implementation. It involves; Plan (set up a plan and expect results); Do (execute the plan); Check (verify anticipated result achieved); and Act (evaluate; do it again). . Just in time (JIT): - This is a technique aimed primarily at minimizing flow times within a production as well as response times from suppliers and to end-users. In any case, JIT is a way of thinking, working and managing to eliminate wastes in processes. Value stream mapping: - A technique for visually analyzing, documenting and improving the flow of a process in a way that highlights improvement opportunities.

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