Enhancing the Golden Triangle (Cost, Time, Quality) in Infrastructure Projects through Risk Management: A Case Study of the Algiers Metro Project

Infrastructure development plays a pivotal role in societal and economic growth. serving as the backbone of modernization and progress. Within this context, underground construction including metro systems is crucial for enhancing urban connectivity and addressing challenges associated with urbanization (S​z​y​m​a​ń​s​k​i​,​ ​2​0​1​7). However, the construction industry, particularly in Algeria, faces a highly competitive and risk-prone environment compounded by economic fluctuations and the complexity of large-scale projects.

One of the most persistent challenges in construction projects is managing the interplay between cost, quality, and time often referred to as the "Golden Triangle" of project management. These three factors are deeply interconnected and failure to balance them can lead to project delays budget overruns and compromised quality (E​s​m​a​e​i​l​i​p​o​u​r​ ​e​t​ ​a​l​.​,​ ​2​0​1​1). Inadequate risk assessment and management practices are frequently cited as primary contributors to these issues with the burden of risk often borne by project stakeholders (M​a​h​a​m​i​d​,​ ​2​0​1​1).

In this context, risk management emerges as a critical tool for navigating uncertainties and improving project outcomes. By systematically identifying, analyzing and mitigating risks, project managers can enhance the likelihood of achieving project objectives. The international standard ISO 31000:2018 provides a comprehensive framework for risk management emphasizing a structured and consistent approach that aligns with international best practices (K​h​a​i​r​u​l​l​a​h​ ​e​t​ ​a​l​.​,​ ​2​0​2​2).

This study focuses on the Algiers Metro Project, a high-profile infrastructure initiative undertaken by Cosider, an Algerian construction and public works company. The project exemplifies the complexities and risks inherent in large-scale underground construction. By evaluating the application of risk management practices guided by ISO 31000:2018, this research seeks to determine their contribution to improving the Golden Triangle parameters of cost, quality and time.

The central question driving this research is: How can risk management, based on ISO 31000:2018, address the challenges posed by project risks to the Golden Triangle thereby enhancing the success of infrastructure projects? To answer this, the study combines theoretical insights with a practical analysis of the Algiers Metro Project offering recommendations for improving risk management practices in similar contexts.

Risk management is a fundamental component of project management particularly in infrastructure projects where complexity and uncertainties pose significant challenges. The existing body of literature on risk management in infrastructure projects emphasizes not only the avoidance of risks but also the transformation of risks into competitive advantages (O​s​e​i​-​K​y​e​i​ ​e​t​ ​a​l​.​,​ ​2​0​2​2). These strategies are particularly crucial in the context of large-scale projects such as metro systems where risks related to time, cost and quality collectively known as the Golden Triangle must be carefully managed. The following review explores the role of ISO 31000:2018 in enhancing risk management practices within infrastructure projects with a particular focus on the Algiers Metro Project developed by Cosider Company.

The ISO 31000:2018 standard provides a comprehensive framework for managing risks across various sectors. It emphasizes the integration of risk management into an organization's overall governance and decision-making processes ensuring alignment with strategic objectives (I​S​O​,​ ​2​0​1​8). The international standard facilitates the identification, assessment and management of risks in a proactive manner moving away from reactive strategies. For infrastructure projects. ISO 31000:2018 offers tools that help in identifying risks early, allowing for mitigation measures to be implemented before risks evolve into major issues.

Metro projects, particularly those involving complex systems such as Tunnel Boring Machines (TBMs), are inherently risky due to the technical challenges they present. D​i​n​g​ ​e​t​ ​a​l​.​ ​(​2​0​1​2​) and S​h​a​r​a​f​a​t​ ​e​t​ ​a​l​.​ ​(​2​0​2​1​) provided insights into risk identification methods in metro construction with a focus on the use of Bow-Tie analysis. This method combines fault tree and event tree analysis to create a visual model of how specific risks can lead to undesirable outcomes. It is particularly useful for understanding and mitigating risks related to TBM operations including equipment failure delays and unforeseen geological conditions. Z​h​a​n​g​ ​&​ ​G​u​a​n​ ​(​2​0​1​8​) demonstrated the relevance of Bow-Tie analysis in TBM tunneling projects offering a model directly applicable to metro construction. Bow-Tie analysis is a visual method for identifying and analysing risks that combines qualitative and quantitative evaluations to map risk pathways showing causes, critical events and consequences (Liu. et al., 2022; Rajgor & Mamata. 2024).

In addition to Bow-Tie analysis, studies have explored various risk management strategies such as preventive measures (e.g., accurate project scheduling) and remedial actions (e.g., close supervision) that are vital for the successful execution of metro projects. Failure Modes and Effects Analysis (FMEA) is a systematic proactive tool for identifying potential failure points, their causes and the effects of these failures on a system process or project. It is widely employed across industries for risk identification and assessment purposes. The Fishbone Diagram visually identifies risks by categorizing them into six main areas: man, machine, method, material, measurement and environment (V​a​r​s​h​a​ ​e​t​ ​a​l​.​,​ ​2​0​1​5). It supports brainstorming to uncover root causes of delays and safety issues. I​q​b​a​l​ ​e​t​ ​a​l​.​ ​(​2​0​1​5​) highlighted the importance of these strategies in minimizing risks and ensuring timely and cost-effective delivery of metro systems. Furthermore, strategic risk management within the Golden Triangle of time, cost and quality is crucial for mitigating delays budget overruns and maintaining quality standards throughout the project lifecycle (K​h​a​l​i​d​,​ ​2​0​1​7; Z​i​d​a​n​e​ ​&​ ​A​n​d​e​r​s​e​n​,​ ​2​0​1​8).

The Golden Triangle of time, cost and quality serves as a critical framework for evaluating the success of infrastructure projects. Effective management of these three elements requires a combination of risk management strategies and tools. Among the most widely used techniques is Earned Value Management (EVM). which allows project managers to track project performance against planned objectives providing an early indication of potential risks related to time and cost. EVM is a valuable tool for integrating risk management practices into the project lifecycle, ensuring that risks associated with time, cost and quality are identified and mitigated promptly (A​m​i​n​i​ ​e​t​ ​a​l​.​,​ ​2​0​2​3; H​u​s​s​e​i​n​ ​&​ ​M​o​r​a​d​i​n​i​a​,​ ​2​0​2​3). Applying EVM within the context of ISO 31000:2018 helps managers better understand the interdependencies between time, cost and quality enabling them to make informed decisions that optimize resources and minimize risks.

Metro construction projects face unique risks due to the complexities of underground infrastructure, the need for coordination among multiple stakeholders and the technical challenges of tunneling. The Algiers Metro Project, being developed by Cosider Company, presents an important case study for understanding how risk management practices can be applied in such complex settings. The project has faced significant challenges including delays and budget overruns which have underscored the need for robust risk management strategies. The application of ISO 31000:2018 can help address these challenges by providing a structured approach to risk management that is adaptable to the specific conditions of the Algiers Metro Project. This includes proactive risk identification, stakeholder engagement and the use of risk mitigation strategies such as HAZOP (Hazard and Operability Study) and FMEA (Failure Mode and Effect Analysis) to minimize risks related to safety scheduling. and budget.

This research contributes through the integration of multiple risk assessment methods. While previous studies have applied the ISO 31000:2018 standard to infrastructure projects, this study proposes a unique combination of FMEA, Bow-Tie and Fishbone methodologies to systematically analyze risk factors. This multi-method approach is expected to provide a more comprehensive risk assessment.

The case study of the present research focuses on the Algiers M28 Metro extension project, a vital infrastructure initiative aimed at extending the metro line from El Harrach Centre to Algiers International Airport (New Terminal). Spanning 10 kilometres, the project is notable for its complexity and significance as it includes the construction of 9 metro stations and 10 ventilation shafts designed to enhance urban connectivity and mobility in Algiers (Figure 1):

The present research aims to bridge the gap in the existing literature by examining the application of ISO 31000:2018 to the Algiers Metro Project. Unlike many studies that provide general insights into risk management, this study examines the real-world challenges faced by the Cosider company in managing risks related to time, cost and the technical complexities of metro construction. By employing a case study approach, this research will offer practical insights into how risk management methodologies such as Bow-Tie analysis, EVM and others can be applied to large-scale infrastructure projects. The Algiers Metro Project offers a unique opportunity to examine how ISO 31000:2018 can be used to improve risk management practices in the context of Algerian infrastructure development.

The integration of ISO 31000:2018 into the management of risks within metro projects provides a structured and adaptable framework that enhances decision-making and project outcomes. By addressing the risks associated with time, cost and quality, ISO 31000:2018 ensures that projects are delivered efficiently and effectively. The Algiers Metro Project serves as a pertinent case study for the application of these methodologies, offering valuable insights that can inform future metro projects in Algeria and similar infrastructure developments worldwide. This research contributes to the growing body of literature on risk management in large-scale infrastructure projects, providing both theoretical insights and practical solutions to the challenges faced by project managers.

This study adopts a qualitative approach to analyze risk management practices in the Algiers Metro Project. The methodology is designed to ensure a comprehensive understanding of the risks encountered during project execution and how they were managed.

Various data collection methods were employed, including document analysis, direct observations, interviews with key project personnel and brainstorming sessions. These methods provided a holistic view of risk identification, assessment, and mitigation strategies, ensuring a robust and well-founded analysis of risk management practices in line with ISO 31000:2018.

We reviewed the company's documents in accordance with its internal regulations and confidentiality policies. The SWOT analysis highlighted internal strengths and weaknesses, as well as external opportunities and threats, providing insights into risk factors. The internal audit report was also consulted to assess internal controls and compliance, revealing potential gaps in risk management practices. These two documents were provided to us by the project manager, as they contain essential information for identifying and addressing risks and play a crucial role in developing effective risk management strategies for the project.

The observations focused on the implementation of risk management practices according to the ISO 31000:2018 standard. Note-taking and audio recordings were used to document risk management strategies. The main risks identified concerned time, cost and quality, with proactive mitigation measures in place. Communication between stakeholders ensured effective risk management. Data was collected over a 26-day period, from April 15. 2024. to May 11. 2024.

Semi-structured interviews were conducted with seven (07) key personnel in the project (Table 1). The selection of this sample was based on the expertise of the respondents: project managers and senior risk specialists with more than ten years of experience.

The interviews were audiotaped, notes were taken, and relevant documents were consulted on-site. Data collection was conducted over a 26-day period, from April 15. 2024. to May 11. 2024. During this time. a comprehensive risk identification process was carried out (See interview guide in Appendix A).

During the brainstorming session, seven (07) key stakeholders were gathered, including Engineers, Quality Department Members, the Procurement and Planning Manager and the HSE Manager. The session lasted three (03) hours during which participants collaboratively identified the root causes of the primary risks affecting the project.

This multi-method approach to data collection was adopted to triangulate the results and draw valid conclusions with minimal biases. Additionally, it allowed for a deeper understanding of the challenges associated with risk management in this complex construction project. The results highlighted the importance of a collaborative process in identifying critical risks and contributed to the development of strategies to effectively address these challenges.

The effective implementation of ISO 31000:2018 requires a structured approach that begins with defining the project context to ensure a comprehensive understanding of risk factors.

The context provides an understanding of the organization's objectives, the internal and external environment in which it operates to achieve these objectives and the role of stakeholders involved.

The external context includes factors outside the organization that can impact the project either directly or indirectly. These factors encompass political conditions, economic trends. social and cultural influences, technological advancements, environmental concerns, legal frameworks and the influence of stakeholders within the specific project environment.

The internal context refers to factors within the organization that influence the project's entire life cycle. These include the organizational structure, strategic priorities, financial and technical capabilities, decision-making processes and information systems. Additionally, relationships with internal stakeholders and organizational culture should also be considered.

Risk analysis was carried out using Bow-Tie Analysis and the Fishbone Diagram. At the end of this phase, the causes of the identified risks were defined.

The evaluation was carried out in two stages: evaluating the risks based on their severity and occurrence to establish the Risk Assessment Grid using the Failure Modes and Effects Analysis (FMEA) method, then assessing the impact of risks on the three factors: Quality, Cost and Time, then:

First, for risk assessment, two key factors were considered. Occurrence refers to the likelihood of a risk happening during the project. Evaluating occurrence helps determine the probability of the risk and enables early preventive action. Severity of Potential Damage assesses the possible consequences or harm if the risk materializes. Understanding severity helps prioritize risks and allocate resources for mitigation.

These two factors are combined through multiplication to determine the criticality of each risk or Risk Priority Number (RPN) providing a clear understanding of both its likelihood and potential impact (Table 2 and Table 3). This approach supports informed decision-making and effective risk management throughout the project.

RNP $=$ SEVERITY $\times$ OCCURRENCE

• SEV (Severity): Rated on a scale from 1 to 64. Higher values indicate risks with a more severe impact if they occur;

• OCC (Occurrence): Rated on a scale from 1 to 16. Higher values indicate risks that are more likely to occur;

• RPN (Risk Priority Number): Calculated by multiplying severity by occurrence for each risk. The RPN helps prioritize risks for mitigation or management efforts. Higher RPN values indicate risks that require higher priority for mitigation.

Second, risks are prioritized by calculating the average of their impacts and associated probabilities with scores categorized into low, moderate or high priority using specific methods and visual indicators such as colors. The analysis highlights which risks require immediate action based on their severity and likelihood while lower-priority risks may instead be monitored. To achieve this, we used the matrix proposed by P​M​I​ ​(​2​0​1​3​) (Table 4 and Table 5).

• Probability: This represents the likelihood of a risk occurring, usually on a scale from 0 to 1.

• Impact: This indicates the potential severity or consequence of the risk if it occurs, also on a scale from 0 to 1.

• Matrix Value: This is the product of probability and impact, showing the overall risk score. It helps prioritize risks.

RStudio (Integrated Development Environment (IDE)) was used for data visualization. This tool enabled the creation of graphs illustrating the relationship between risk impact and probability over time, providing valuable insights into the risks that significantly affect time, cost and quality.

An action plan was developed specifying the actions, the responsible party and the implementation timeline.

Based on interviews, direct observations and brainstorming sessions, a list of 43 potential risks was developed. These risks were classified into five categories: operational, technical/design/planning, material management, execution and human resources (Table 6).

According to Table 6, key risks included compliance challenges, design constraints, supply chain disruptions, safety hazards and workforce issues. By leveraging team expertise and past experiences, this process enhances risk control, preparedness and project success.

According to Table 6, key risks included compliance challenges, design constraints, supply chain disruptions, safety hazards and workforce issues. By leveraging team expertise and past experiences, this process enhances risk control, preparedness and project success.

For risk analysis, we combined the Fishbone Diagram method and the Bow-Tie method. Fishbone Diagrams were developed to analyze the causes associated with the lack of equipment and resources within material management. The analysis was structured around five main categories: People, Methods, Materials, Environment, and Equipment. Special attention was given to the equipment category. In addition, Bow-Tie diagrams were established (see risk causes in Appendix B).

We present below the diagrams related to the risk associated with TBM (Figure 2 and Figure 3):

The risk assessment results. based on their Severity and Occurrence. (are presented in Appendix C.) Based on this evaluation. the risks have been positioned in the risk assessment grid (Table 7).

Based on the risk assessment grid, the company must address three (3) priority I risks, followed by seven (7) priority II risks, fifteen (15) priority III risks and eighteen (18) priority IV risks.

Using the matrix proposed by P​M​I​ ​(​2​0​1​3​) (see Table 4), the impact of the identified risks on the three factors time, cost and quality was evaluated (see Appendix D for evaluation details).

Based on the results, we developed RStudio visualizations illustrating the impact of risks on time, cost and quality (Figure 4, Figure 5, and Figure 6 respectively).

Failure to meet delivery deadlines failure to control risks at the project level and poorly addressed non-conformities with unresolved stop points were evaluated as high-risk issues that could cause schedule delays. Once these risks are controlled, time delays can be prevented. One major benefit of conducting such a risk assessment is that it highlights critical areas to focus on ensuring the project runs smoothly and remains under control.

Critical risks affecting the cost aspect include improper equipment utilization, inadequate articulation or understanding of project requirements, failure to manage risks at the project level and inability to achieve project management objectives. Neglecting these risks could result in additional project costs.

The risks that may challenge the project's quality include for example failure to properly use equipment. These mentioned risks are significant and can greatly impact the project. For instance, if equipment is not used correctly, it can negatively affect the quality potentially leading to the project not being delivered to the client according to their requirements and expectations. Therefore, it is crucial to address these risks while they are still manageable to deliver what the client desires and meet the project objectives.

Actions for assessing and managing risks within Cosider Company were defined. Specific measures were outlined to address various risks detailing the individuals or teams responsible for each action and the frequency of implementation (see action plan in Appendix E.)

The risk management action plan presented demonstrates a comprehensive and multifaceted approach to addressing the identified risks. It highlights the following points:

• Comprehensive Approach: The plan covers a wide range of risks and outlines a diverse set of actions to address them. This comprehensive approach is commendable as it demonstrates a thorough risk assessment and a commitment to proactive mitigation.

• Stakeholder Involvement: The plan emphasizes the importance of collaboration, coordination and engagement with various stakeholders including regulatory bodies, suppliers, customers and project team members. This collaborative approach can help build buy-in enhance information sharing and improve the effectiveness of the risk management efforts.

• Continuous Monitoring and Improvement: The plan includes actions related to ongoing monitoring. such as regulatory watch, supplier performance measurement and strategic environmental scanning. This reflects a recognition of the dynamic nature of risks and the need for continuous adaptation and improvement.

• Training and Competency Development: The plan prioritizes training and competency development for various roles, from storekeepers to project team members. This focus on building internal capabilities is crucial for ensuring effective implementation and sustainable risk management practices.

• Proactive Measures: Several actions such as anticipating and defining the choice of methods introducing new suppliers and diversifying supply sources, demonstrate a proactive approach to risk management. This forward-looking mindset can help the project anticipate and adapt to emerging risks.

• Operational-level Details: The plan provides a good level of detail in terms of specific actions, responsible parties and deadlines. This granularity can facilitate clear accountability and effective execution of the risk management strategies.

• Potential Areas for Improvement: While the plan is comprehensive, it could be further strengthened by incorporating more quantitative risk assessment techniques such as risk scoring or Monte Carlo simulations to prioritize and allocate resources more effectively. Additionally, the inclusion of contingency planning and escalation procedures could enhance the project's overall resilience.

Overall, the action plan presents a well-structured and multifaceted approach to risk management, reflecting a good understanding of the project's risk landscape and a commitment to proactive risk mitigation.

The results illustrate the significant role of risk management. as guided by ISO 31000:2018, in improving the Golden Triangle—Time, Cost and Quality—in infrastructure projects as evidenced by the Algiers Metro Project. The findings were analyzed in alignment with the principles of ISO 31000:2018 and the specific risks identified during this study's qualitative investigation. The qualitative analysis, supported by interviews, internal documents and site observations, identified 43 key risks that directly impacted the execution of the Algiers Metro Project. These risks spanned technical, financial, environmental and operational categories. Risk mitigation strategies applied within the ISO 31000:2018 framework enabled the project team to anticipate, assess, and manage these risks systematically. The methods employed—FMEA analysis, Bowtie analysis and Fishbone diagrams—provided a structured approach to identifying root causes and potential consequences of risks fostering informed decision-making and proactive intervention.

The findings highlight that systematic risk management, in accordance with ISO 31000:2018 principles, enhanced the project's capacity to manage deviations in timelines, resource allocation and unforeseen challenges. Notably, mitigation strategies contributed to better control of delays and cost overruns. thereby aligning the project's outcomes with the expectations of the Golden Triangle. These findings are consistent with ISO 31000:2018 principles, which emphasize the iterative and integrated nature of risk management across all project stages. ISO 31000:2018 advocates continuous risk monitoring, stakeholder engagement and evidence-based decision-making practices that were evident in the Algiers Metro Project's management processes. The systematic application of risk identification and assessment tools enhanced foresight, ensuring that mitigation strategies were implemented in alignment with strategic objectives.

Furthermore. the study confirms ISO 31000:2018’s emphasis on integrating risk management into organizational culture. The findings indicate that fostering a culture of risk awareness within the Cosider team strengthened collaboration, stakeholder engagement and accountability. These cultural shifts enhanced the project team’s ability to navigate risks and ensure timely project delivery. These conclusions align with the findings of M​u​s​t​a​r​o​ ​&​ ​R​o​s​s​i​ ​(​2​0​1​3​), who highlighted that continuous monitoring, stakeholder engagement and the development of internal capabilities are key strengths of an effective action plan.

The Golden Triangle serves as a critical benchmark for infrastructure projects. The Algiers Metro Project’s ability to maintain control over these three interrelated parameters can be attributed to systematic risk management practices. Risk strategies identified through FMEA and Bowtie analyses were instrumental in addressing risks that could lead to delays or resource inefficiencies. For example, financial risks related to labor shortages and equipment availability were mitigated through preemptive actions such as the reallocation of financial resources and supplier diversification.

The study demonstrates that risk management, guided by ISO 31000:2018 principles, effectively improved time performance by minimizing project delays, cost management by addressing financial risks at an early stage and quality assurance by implementing targeted interventions to mitigate technical uncertainties.

The findings align with existing literature emphasizing the importance of systematic risk management in achieving project success. Previous studies have shown that ISO 31000:2018 fosters a proactive rather than reactive approach to risk, aligning risk management practices with project objectives and strategic planning. However, this case study contributes to the literature by illustrating how these principles directly impact large-scale infrastructure projects such as the Algiers Metro Project and by demonstrating the effective application of qualitative methods such as FMEA, Bowtie and Fishbone diagrams for risk assessment.

Nonetheless, this study reveals unique insights, notably the critical role of cultural adaptation and stakeholder engagement, underscoring that risk management is not solely a technical or procedural exercise but also a social one requiring a commitment to shared learning and collaboration.

The findings provide important practical implications for infrastructure project managers and decision-makers. They suggest that integrating ISO 31000:2018 principles can enhance resource allocation, improve stakeholder alignment and foster a more adaptive approach to unforeseen risks. Moreover, the practical application of qualitative risk analysis methods such as FMEA and Bowtie supports better strategic foresight by offering a clearer visualization of risk pathways and consequences.

The study delves into the perceptions and practices of risk management within the construction industry, with a particular focus on the Algiers metro construction project. Despite the ubiquitous presence of risk in construction endeavors, the understanding and formal application of risk management processes often fall short of theoretical ideals. Through qualitative methods, the study uncovers insights into how risks are perceived, managed and the willingness of industry professionals to embrace structured risk management processes.

The findings suggest a gap between theoretical concepts and practical application, with an emphasis on the need for profitability and simplicity in risk management practices. Additionally, the study identifies key suggestions for enhancing risk management within construction projects, along with acknowledging inherent limitations and proposing avenues for future research and extension.

From our experience, we suggest that Cosider Company establish formal risk management processes, invest in training, allocate adequate resources, promote risk awareness, utilize technology and continuously improve by regularly reviewing past projects to identify areas for enhancement in risk management practices. These measures can strengthen its risk management practices and improve project outcomes.

Unlike previous studies, which focus on generic risk management approaches, this research provides a detailed analysis specifically tailored to the context of the Algiers Metro Project. The study identified 43 major risks and assessed their impact on the Golden Triangle (cost. time. and quality) offering practical insights particularly relevant to large-scale infrastructure projects. One of the main contributions of this study is the identification of equipment-related risks as a dominant factor in project delays and cost overruns. This aspect, which has been little explored in previous literature, highlights the need for better resource allocation and preventive maintenance strategies.

While the findings are promising, it is important to acknowledge certain limitations. This study focused on a single case study (the Algiers Metro Project with Cosider), which may limit the generalizability of the findings. Additionally, while the qualitative approach provided deep insights into risk processes. Future research could integrate quantitative risk modeling for a more comprehensive analysis. Moreover, the 26-day observation period may not account for long-term risks, such as seasonal delays. Therefore, it would be relevant to extend the monitoring period, potentially covering multiple project phases or seasonal cycles to enhance the comprehensiveness of the risk assessment.

Building on this study's insights, future research should explore comparative case studies across multiple infrastructure projects to identify common patterns and unique risk management practices. Further studies could also examine the long-term effects of ISO 31000:2018 adherence on project lifecycle outcomes and explore technological integration in risk management tools.