Identification of core risk factors and risk diffusion effect of urban underground engineering in China: A social network analysis

Risk assessment plays an important role in urban underground engineering construction. Although the traditional risk assessment methods can quantitatively evaluate the risk of engineering project, they have limited capabilities in identifying the most influential risks and analyzing development mechanism of risks. Based on this, a novel risk analysis method is proposed to identify the core risk factors and analyze the risk diffusion effect of risk factors. Then, according to the characteristics of strong correlation of risk factors, a network of risk factors for urban underground engineering in China was constructed from multi-dimensional perspectives such as technology, organization management, environment and human factors in the whole life cycle. Furthermore, the core risk factors and the risk diffusion effect of risk factors are analyzed based on this novel method for urban underground engineering in China. The research results show that R1 (Unreasonable personnel arrangement of safety management organization), R4 (No regular inspection and supervision mechanism), R6 (Weak safety awareness of the personnel), and R12 (Unreasonable construction technology) are core risk factors of urban underground engineering, among which R1 and R4 have strong risk diffusion effects. Last, the accidents of subway construction from 2017 to 2019 in China were collected to verify the research results. The validation shows that the conclusions obtained in this study are in accordance with the results of accident case analysis. The research provides a new research idea of risk management and is helpful to target and manage the risk factors for project managers.