## 5 Conclusions  
This study identified and examined the interdependencies among the time and cost risks of pile installation in the KSA's construction industry. The research methodology involved several steps. Firstly, data were collected to gather all the pile installation risks in the literature. Then, the listed risks were reviewed and examined, and pile construction experts assessed other risks via semi-structured interviews. After obtaining the risks that may influence pile construction in the KSA, a survey was designed and distributed to the twelve experts to measure the degree of probability and impact of each of the risks using a five-point Likert scale. The questionnaire data were prepared. The data were then magnified using a Monte Carlo simulation. The elaborated data were then utilized to develop time and cost risk interdependencies for two terrain conditions (sand and rock). The results of the interdependencies were compared with the literature.  
This study's findings show that construction risk indirectly impacts the time and cost needed to install a pile time and cost in sand due to site and economic risks through design risks. Moreover, site hazards and equipment risks indirectly affect the cost of installing piles in rock. The significant risk groups for the time needed to install a pile in the sand are construction risks (safety issues, survey errors, and site handling mistakes), management risks (poor communication between project stakeholders and poor staff efficiency), owner-generated risks (unqualified owner representatives and the delay or refusal of compensation to the contractor), and site risks (when the investigation samples do not cover the entire study area and soil type). The crucial time risk groups for constructing a pile in rock are design risks (the distance between the pile and the adjacent pile and the nature of the project), economic risks (a lack of funds: a lack of cash flow from the contractor, and delays in the delivery of services and spare parts), equipment risks (a delay in and/or failure of logistics services and the size of the withdrawal units), management risks (poor communication between project stakeholders and a lack of quality management) and owner  
Figure 9: Rank of significance from the results of the study by [PERSON] et al. [5].  
generated risks (failure to finance the project and unqualified owner representatives). The substantial cost risks of installing a pile in rock are the distance between the pile and an adjacent pile, the nature of the project, incidents with internal or external stakeholders, improper maintenance, failure to finance the project, an owner's ultra-standard expectations and requirements, the soil type, and issues due to size limitations. These results aid the building industry in more efficiently assessing time and expense concerns. This paper is limited to bored piles in the construction stage. The paper did consider the mutual relationship between time delays and cost overruns.  
Further studies are recommended to investigate the risks of the interdependency model using artificial intelligence (AI) or machine learning (ML). The paper was limited to a risk assessment of one type of pile: a bored pile. In addition, the types of sub-ground conditions were limited to sand and rock.