Decision making involves clearly defining objectives, identifying potential solutions, evaluating their feasibility, analyzing the consequences and outcomes of each option, and ultimately selecting and implementing the best course of action. The quality of management is largely determined by the quality of these decisions, as they directly impact the effectiveness of plans and programs, the success of strategies, and the overall quality of the outcomes achieved [
47]. When decisions are made based on multiple criteria, the decision maker is more likely to be pleased and satisfied. Criteria can be quantitative or qualitative [
48]. Managers can make rational decisions by taking into account various decision-making criteria, which may conflict with one another [
49]. The main purpose of this research is to identify and prioritize the risks of GCPs in Saudi Arabia. The development of green buildings faces several challenges, which are largely tied to environmental, economic, and socio-political factors. Despite the country’s commitment to sustainability, the high upfront costs of green technologies, a lack of awareness among stakeholders, and resistance to adopting new construction methods present significant barriers in Saudi Arabia. Additionally, the scarcity of locally sourced green materials and limited regulatory frameworks further complicate the widespread adoption of sustainable construction practices. Green building projects in Saudi Arabia encounter a range of risks that can significantly impact their success. One major concern is the fluctuation of currency exchange rates, which can affect the cost and availability of imported eco-friendly materials essential for sustainable construction. Additionally, there is often resistance from various stakeholders toward adopting sustainable innovations, which can hinder project implementation and acceptance. Moreover, uncertainty surrounding the long-term benefits of green building initiatives poses another challenge, as it may lead to hesitation among investors and decision makers. These factors underscore the critical need for robust risk management strategies tailored to the unique circumstances of GCPs. By effectively addressing these challenges, stakeholders can enhance the likelihood of successful project execution and contribute to the overall sustainability goals in the region.
This section provides a comprehensive overview of the methodology adopted for implementing the research, elaborating on the specific algorithms and processes employed.
2.1. Data Collection and Risk Identification
The participants ranged in age from 35 to 60 years, with an average age of 47 years, reflecting a seasoned group of professionals. Regarding educational qualifications, 65% of the experts held advanced degrees (Master’s or Ph.D.) in relevant fields, such as environmental science, civil engineering, and architecture, while the remaining 35% possessed bachelor’s degrees with extensive practical experience in the construction industry. The average length of work experience among the participants was 22 years, ensuring that the insights provided were grounded in practical, real-world experience.
Data collection involved a two-phase process. Initially, semi-structured interviews were conducted to gain qualitative insights into the experts’ perceptions of risks in green construction. These interviews helped to identify the key areas of concern, such as material quality, resistance from stakeholders to adopting green technologies, regulatory uncertainties, and economic volatility. Following the interviews, a comprehensive survey was developed based on the input received, which was then distributed to all participants for further quantitative assessment.
The survey included four detailed questionnaires with both open-ended and Likert-scale questions, focusing on the frequency, impact, and manageability of various risks. The experts were asked to rate the severity of each identified risk factor. Their responses were then compiled and analyzed, allowing for a thorough screening of risks. Only those risks that were rated as having a significant impact on project timelines, costs, or sustainability were included in the final list for further evaluation. This rigorous process ensured that the most relevant and critical risks were prioritized for analysis and risk mitigation in subsequent stages of the study. The experts completed a questionnaire on the importance of each risk in GCPs. Risks with values greater than the average of the total values were screened and confirmed. This is considered efficient, so it is chosen, and any risk with a value less than the average of the total values is deemed ineffective and removed.
The first questionnaire intended to identify the risks to GCPs. In this regard, the experts were first asked to rate the significance of the risks on a scale of 1 (very low importance) to 5 (very high importance). Then, the experts were asked to describe the risks in terms of specificity and generality. All components whose average degree of importance exceeded the overall average were chosen. The second questionnaire is used to prioritize the criteria in the TOPSIS technique. The experts were asked to rank the criteria based on their personal mentality. The final rating can be determined by taking into account the opinions of all experts, as well as the average rating of each criterion. The third questionnaire is distributed to experts after the criteria have been ranked in order to assess their relative importance. The fourth questionnaire, which is a matrix with risks and criteria, is given to the experts to evaluate each risk using a scale of 1 to 5.
2.3. Fuzzy TOPSIS and Criteria Weighting
In this section of this study, the fuzzy TOPSIS method was utilized to allocate weights and prioritize the identified risks. This methodology was chosen due to its effectiveness in managing the uncertainties and ambiguities that are commonly encountered in expert assessments. These uncertainties frequently arise from incomplete or vague information found in practical scenarios, such as risk evaluations in GCPs. By integrating fuzzy logic into the conventional TOPSIS framework, the approach facilitated more precise and flexible rankings of the risks involved, allowing for a more robust decision-making process. This enhancement provides decision makers with a clearer understanding of the potential risks, thereby improving their ability to implement effective risk management strategies [
60,
61,
62].
TOPSIS is grounded in the idea that the best possible solution should simultaneously minimize its distance from the positive ideal solution (PIS) and maximize its distance from the negative ideal solution (NIS). In practice, this means identifying the alternative that is closest to the ideal scenario and furthest away from the worst-case scenario. When employing fuzzy TOPSIS, the process is enhanced by the use of fuzzy numbers, which serve to represent both the criteria weights and the performance ratings of each alternative option under consideration. Fuzzy numbers are particularly useful because they allow for a more comprehensive and flexible representation of uncertainty and imprecision, common in complex decision-making environments [
63,
64].
In risk assessments of GCPs, expert opinions often come with a degree of ambiguity, due to incomplete or uncertain data. Fuzzy TOPSIS addresses this issue by incorporating fuzzy sets that capture the vagueness in expert judgments, thereby providing a more detailed evaluation. This nuanced approach improves the accuracy of decision making by allowing for a richer, more adaptable comparison of risks. As a result, decision makers can achieve more reliable rankings of the alternatives and better manage the complexities involved in green building initiatives.
In the fuzzy logic approach, each risk criterion was evaluated using triangular fuzzy numbers (TFNs) to represent the degree of importance. A TFN is defined by three parameters,
, where
is the lower bound,
is the most likely value, and
is the upper bound. These values were determined based on expert input, allowing for flexibility in the evaluation process. A TFN
can be represented with Equation (1), as follows:
where
represents the lowest value of the fuzzy number,
represents the most probable value, and
represents the highest value of the fuzzy number.
The fuzzy TOPSIS method involves several key steps to evaluate and prioritize risks in GCPs. First, the decision matrix undergoes fuzzification, converting crisp values into fuzzy numbers based on expert assessments. Next, fuzzy weights for each criterion are determined to reflect their relative importance. Following this, a normalized fuzzy decision matrix is constructed to ensure comparability across different criteria. The method then identifies the fuzzy positive ideal solution (FPIS) and fuzzy negative ideal solution (FNIS), representing the best and worst outcomes for each criterion, respectivley. The distances from both the FPIS and FNIS are calculated for each alternative, allowing for a performance evaluation relative to the ideal solutions. Finally, the closeness coefficient (CC) is computed to rank the alternatives based on their proximity to the FPIS, thereby facilitating informed decision making in the context of green construction initiatives.
The decision matrix was established, organizing the alternatives (risks) along the rows and the criteria along the columns. Each element within the decision matrix was subsequently converted into a fuzzy number, reflecting expert evaluations using terms such as “low”, “medium”, and “high”.
Each criterion was assigned a weight using fuzzy numbers, with expert opinions aggregated to calculate the fuzzy weight for each criterion. The aggregated weight for a criterion was represented by a triangular fuzzy number (TFN) denoted as . This representation captures the uncertainty and variability in expert judgments, allowing for a more precise evaluation of the importance of each criterion within the decision-making process. By utilizing TFNs, the method effectively incorporates diverse perspectives, enhancing the overall robustness of the risk assessment framework.
The decision matrix was normalized to ensure comparability across different criteria. The normalized value
for each element was calculated using Equation (2), as follows:
where
represents the fuzzy value of the
-th alternative concerning the
-th criterion.
To determine the fuzzy positive ideal solution (FPIS) and fuzzy negative ideal solution (FNIS), the FPIS
and FNIS
were established according to Equation (3). The FPIS is defined as the best possible performance across all criteria, while the FNIS represents the worst possible performance. These ideal solutions serve as benchmarks for evaluating the performance of each alternative in relation to the criteria set forth in the decision-making process.
The FPIS signifies the optimal performance for each criterion, whereas the FNIS denotes the least favorable performance. To evaluate the performance of each alternative, the distance from both the FPIS and FNIS was computed using Equation (4). This calculation enables a comprehensive assessment of how closely each alternative aligns with the ideal and non-ideal solutions, facilitating a clearer ranking of the risks involved. By analyzing these distances, decision makers can better understand the relative strengths and weaknesses of each alternative in the context of the established criteria.
where
and
are the distances between the normalized fuzzy values and the FPIS and FNIS, respectively.
The closeness coefficient
for each alternative was calculated to assess its relative proximity to the fuzzy positive ideal solution (FPIS), as outlined in Equation (5). This coefficient provides a quantitative measure of how closely each alternative aligns with the ideal solution, enabling decision makers to rank the alternatives based on their performance. A higher closeness coefficient indicates a better fit to the FPIS, facilitating informed choices regarding risk management in GCPs. By analyzing the
values, stakeholders can prioritize alternatives more effectively, guiding their decision-making processes.
The higher the value of , the closer the alternative is to the ideal solution.
The fuzzy weight for each criterion
was calculated using the following aggregation method based on the input of multiple experts (Equation (6)):
where
is the number of experts, and
is the fuzzy weight assigned by expert
to criterion
.
Finally, the weighted normalized decision matrix was constructed as follows (Equation (7)):
where
represents the weighted normalized value for alternative
under criterion
.
2.4. Machine Learning for Risk Ranking
To refine the risk prioritization in GCPs, an EANN was implemented. The EANN is an advanced form of artificial neural network (ANN) that integrates an emotional learning mechanism into the traditional network structure. This allows it to better model complex and dynamic systems by adjusting neuron behavior based on emotional signals. In the context of this study, the EANN was trained using expert-assigned weights and rankings derived from the fuzzy TOPSIS method. This hybrid model allowed for a refined prediction of the risk hierarchy by combining expert judgment with data-driven analysis [
65,
66,
67].
EANN extends the traditional ANN by introducing an artificial emotional component that regulates the behavior of neurons. Each neuron in the EANN can dynamically adjust its activation, learning rate, and output based on inputs and internal emotional signals. This structure enables the network to better handle uncertainties and adapt to changing conditions, which is particularly useful for risk ranking in GCPs where data may be incomplete or uncertain.
Each node in the EANN is responsible for processing data by incorporating hormone-like signals, denoted as
H1,
H2, and
H3, which influence neuron behavior. These hormones are generated dynamically as the network processes input data and adjusts the weight coefficients. The EANN learns through iterative training, during which the hormone coefficients influence the activation function, performance, and output of each neuron [
68,
69,
70,
71].
The EANN architecture consists of three primary layers and an input layer, and it receives the weighted criteria and closeness coefficients from the fuzzy TOPSIS output. Hidden layers process the input using neuron nodes influenced by emotional hormones. The output layer produces the final risk ranking as a prediction of risk priority. The output of each neuron in the EANN is governed by Equation (8) [
72,
73], as follows:
where
is the output of neuron
;
represents the emotional hormone affecting the neuron;
are the weight coefficients;
is the activation function (e.g., sigmoid or ReLU); and
is the input to neuron
from neuron
. The hormone values
are computed by Equation (9), as follows:
In these equations, the hormones
are influenced by the glandity values, which regulate the emotional intensity of each neuron’s response. The hormone factors
guide the training process by adjusting neuron weights based on the input–output relationship [
74,
75].
The training of the EANN was conducted using the Levenberg–Marquardt (LM) optimization algorithm. This method, which combines the advantages of both gradient descent and Gauss–Newton methods, is particularly suited for solving non-linear least squares problems. It has been widely used for training neural networks due to its efficiency and speed, especially when dealing with complex datasets like those used in this study. The LM algorithm works by iteratively updating the weight coefficients in the neural network to minimize the error between the predicted outputs and the target values (expert-assigned risk rankings). The key idea behind the LM algorithm is to interpolate between the Gauss–Newton method (for fast convergence near the minimum) and gradient descent (for stability far from the minimum). At each iteration, the weight update is computed by Equation (10), as follows:
where
is the update to the weight vector,
is the Jacobian matrix of the network’s error function,
is the error vector (difference between predicted and target outputs),
is the damping factor, adjusted dynamically during training, and
is the identity matrix.
The EANN was initialized with random weights and biases. Hormonal coefficients were also initialized based on random values, reflecting the initial emotional states of the neurons. The input data, consisting of the weighted criteria and Fuzzy TOPSIS outputs, were fed into the network. The EANN processed the data through its layers, producing an output for each risk.
In the training process, the EANN was initialized with random weights and biases. Hormonal coefficients were also initialized based on random values, reflecting the initial emotional states of the neurons. The input data, consisting of the weighted criteria and fuzzy TOPSIS outputs, were fed into the network. The EANN processed the data through its layers, producing an output for each risk. The difference between the predicted output and the target (expert-assigned rankings) was computed as the error vector . The LM algorithm was applied to update the network’s weights by calculating based on the current error. The damping factor was adjusted dynamically. When the error decreased, was reduced, making the update more like the Gauss–Newton method. When the error increased, was increased, making the update more like gradient descent for stability. The training process continued iteratively, adjusting the weights and hormone coefficients until the error converged to a minimum, or a predefined stopping criterion (such as a small enough error or maximum iterations) was reached.
The input to the EANN consists of the weighted criteria and closeness coefficients from the fuzzy TOPSIS output. These serve as the features for each neuron.
Hormonal Influence: During the training process, hormone values adjust the weight coefficients , influencing the neuron’s behavior. The final output is calculated for each risk, producing a ranking based on the learned weights and hormone influence.
Risk Ranking: The predicted risk ranking is derived from the EANN output, providing a hierarchy of risks where a higher value indicates a more critical risk.
Four scenarios for training the model were adopted in this study. In Scenario A, the overall risk evaluation, the EANN model was trained using a broad dataset encompassing various risks identified through expert assessments. The focus of Scenario B, evaluating material quality risks, was specifically on risks associated with material quality and equipment. In Scenario C, evaluating stakeholder engagement risks, the model was trained on data regarding stakeholder engagement and resistance. Scenario D, which evaluated economic and regulatory risks, concentrated on economic fluctuations and regulatory compliance risks.
The proposed flowchart for the algorithm is presented in
Figure 1. The hybrid model enhances decision making in several key ways. First, fuzzy TOPSIS alone ranks risks by processing expert assessments through fuzzy logic, which is useful for capturing ambiguity but does not adaptively refine risk priorities. By integrating EANN, the model not only ranks risks, but also continuously adjusts to patterns in expert-assigned weights, capturing dynamic dependencies between risks. This combination allows for a more robust prioritization that reflects real-world complexities in GCPs.
In response to the inherent complexities and dynamic nature of GCPs, this study integrates an EANN with fuzzy TOPSIS to enhance risk prioritization. While traditional TOPSIS is effective in establishing a fixed ranking of risks based on initial conditions, it lacks adaptability to shifting project environments. EANN adds an adaptive layer to the model by incorporating emotional feedback mechanisms that mimic human-like adjustments in response to changes. This adaptability allows the EANN to dynamically re-evaluate and update risk priorities in real-time, based on evolving project inputs such as material quality shifts, regulatory changes, or stakeholder responses. In this way, the hybrid model provides a robust solution for projects with fluctuating risk profiles, where traditional methods may struggle to account for interdependencies and real-time adjustments. Thus, the inclusion of EANN complements fuzzy TOPSIS by enhancing the model’s responsiveness to complex, interdependent risks, making it highly suitable for the green construction sector.
Fuzzy TOPSIS enables a systematic comparison across multiple criteria by evaluating the closeness of each alternative (risk factor) to an ideal solution. This is particularly beneficial for complex projects like GCPs, where risks vary widely in impact and likelihood. However, standalone fuzzy TOPSIS only offers static ranking without the ability to adapt to changes in risk patterns over time. The EANN component introduces adaptability into the decision-making process. Unlike conventional neural networks, EANN incorporates “emotional” signals or hormone-like factors, which adjust neuron responses based on input complexity. This allows the model to dynamically re-rank risks as more data are introduced or as project conditions evolve, capturing real-time shifts in priorities. The EANN continuously learns from the fuzzy TOPSIS rankings and expert input, adjusting weights to better reflect interdependencies among risk factors. This is especially important in GCPs where risks may be interrelated, making a static model insufficient. The hybrid model combines the ranking stability of fuzzy TOPSIS with the adaptability of EANN, resulting in a system that can respond to both current conditions and potential shifts in risk factors. This hybrid approach supports a more nuanced prioritization of risks, making it more flexible and precise than standalone methods.
The methodology begins with collecting expert evaluations of potential risks in GCPs. We utilized a Likert-scale survey, which gathered responses from 18 experts with four questionnaires. Each risk was rated based on perceived severity and likelihood, providing the input data necessary for risk ranking.
The first stage of risk prioritization involves applying fuzzy TOPSIS in order to handle uncertainties in expert judgments. Fuzzy TOPSIS converts the qualitative risk ratings from the Likert scale into fuzzy values, enabling a more accurate assessment of ambiguous data. Each risk factor is then ranked based on its closeness to the ideal solution, resulting in an initial static prioritization of risks.
After the initial fuzzy TOPSIS ranking, the EANN is introduced to dynamically adapt and refine the prioritization based on changes in input patterns. The EANN operates by simulating an “emotional” feedback mechanism that updates its weighting in response to evolving project data. This enables real-time updates in risk ranking as the model adjusts to patterns and relationships that emerge among risk factors, particularly valuable in the context of green construction, where risks can be highly interdependent and subject to change. The combined output of fuzzy TOPSIS and EANN provides a final, adaptive risk prioritization.