## 4 Research Methodology  
The present study seeks to provide clear guidance for the stakeholders to properly identify and classify the risks of CRCBPs. For this purpose, both qualitative and quantitative approaches were used for the current research. There are three main stages in this study, as displayed in the following flowchart (Figure 1). In situations where the prioritization of decision-making units, based on their relative importance and according to various criteria, is considered, the use of multi-criteria decision-making techniques is suitable for ranking and making rational decisions. Among these techniques, we can mention the multi-criteria decision-making methods that have been used according to the advantages and results as well as the characteristics of the TOPSIS method as a priority of risk prioritization [1]. According to the risk management cycle [1], the first step aimed to identify the risks of the construction of the CRCBPs. To this end, similarly to Khosravi et al. [5], a literature review was carried out and the resulting list of identified risks was strengthened by the application of a three-round Delphi survey method--already used for similar and recent research works (e.g., [51]). Then, to assess the risks, two different risk assessment methods were used in this study: (1) Qualitative and (2) quantitative. The literature review confirms that in many previous studies (e.g., Khosravi et al. [5]), two indicators, \"impact rate\" and \"probability of occurrence\" of risk, have been used to assess risks in construction projects. Qualitative risk analysis is usually a quick and cost-effective tool for prioritizing risks, and it forms the basis for quantitative risk analysis, if needed. The output of this process can be the input to the quantitative risk analysis process or, directly, the input of risk response planning [1]. In this work, qualitative risk assessment has been used for evaluating risks and identifying CRFs. In particular, a survey questionnaire was distributed among identified experts and used to determine the importance of each identified risk. In fact, experts were asked to determine the importance of each risk based on the probability of occurrence and the impact of risks on project objectives (i.e., cost, time, and quality). Accordingly, 25 CRFs were identified. However, some researchers have also emphasized the unreliability of the qualitative assessment of risks [52]. One of the problems with using the probability-risk effect matrix is that the importance of low-probability is that high-impact risks may be overlooked. Because of this approach, high-risk and low-impact risks are equated, which is not necessarily the will of the decision maker. To overcome this problem, quantitative risk assessment was applied to evaluate CRFs. Based on PMI [1], quantitative assessment is performed on risks that have a high priority in qualitative assessment and can significantly affect the project objectives. In this step, new criteria were identified and adopted for assessing the importance of the identified CRFs (i.e., risk response criteria, risk management, influencing the occurrence of other risks, accepting threat, risk detection, risk probability, and vulnerability) (e.g., [48]). TOPSIS was then performed for the quantitative prioritization of CRFs of CRCBPs. It is worth noting that the use of TOPSIS is a greater advancement with respect to similar  
Figure 1: Research methodology of the study. works [5; 53] because it has been proved to work satisfactorily across different application areas and industrial sectors with varying terms and subjects [54], and \"although several techniques have been combined or integrated with the classical TOPSIS, many other techniques have not been investigated. These techniques make the classical TOPSIS more representative and workable in handling practical and theoretical problems\". Stemming from that recognized value of the TOPSIS method, in a series of studies.