Entropy-Based Risk Control of Geological Disasters in Mountain Tunnels Under Uncertain Environments

Abstract

Uncertainty is the main source of risk of geological hazards in tunnel engineering. Uncertainty information not only affects the accuracy of evaluation results, but also affects the reliability of decision-making schemes. Therefore, it is necessary to evaluate and control the impact of uncertainty on risk. In this study, the problems in existing entropy-hazard model such as inefficient decision-making and failure of decision-making are analysed, and an improved uncertainty evaluation and control process are proposed. Then the tolerance cost, the key factor in the decision-making model, is also discussed. It is considered that the amount of change in risk value (R 1 ) can better reflect the psychological behaviour of decision-makers. Thirdly, common attribute decision models, such as the expected utility-entropy model, are analysed, and then the viewpoint of different types of decision-making issues that require different decision methods is proposed. The well-known Allais paradox is explained by the proposed methods. Finally, the engineering application results show that the uncertainty control idea proposed here is accurate and effective. This research indicates a direction for further research into uncertainty, and risk control, issues affecting underground engineering works.

Risk Control Technology for Water Inrush during the Construction of Deep, Long Tunnels

“…en the remaining confidence index of probability of occurrence of risk grade I is allocated by the other four experts. en, the average probability of occurrence of each probability interval, i.e., the confidence index, is calculated using formula (4). Finally, the probability of occurrence of risk grade I can be obtained by using formulae (5) and (6).…”

“…In addition, with the rapid development of China's high-speed railway network in recent years, mountain railway tunnels are also being built [3]. It can be said that the world is witnessing the advent of a prosperous era of tunnel engineering [4]; however, various geological disasters such as collapses [5], rock bursts [6], and water inrush [7] caused by tunnel construction problems have increased, which has caused problems such as property damage, construction delays, cost overruns, and even casualties [8]. Safe and smooth completion on schedule has always been one of the major concerns for the tunnel engineering community.…”

“…For the problem of water inrush risk control during tunnel construction, there are not only geological uncertainties, but also human uncertainties, and it is an important way to improve the reliability of water inrush risk assessment results to deal with the above uncertainties scientifically. For example, Xia et al [4,31] stated that if uncertainty is not properly handled, it may lead to a large difference between the assessment results and the actual risk, which may result in a mismatch between the risk control scheme and the real risk, thus failing to achieve the expected risk control effect. As there are differences in information acquisition and quantification between geological and construction factors, it is necessary to deal with the uncertainty information of initial risk scientifically according to the characteristics of different information.…”