Abstract

Water inrush is one of the most frequent and harmful geological disasters in tunnel construction. In order to effectively prevent and control the occurrence of water inrush, an early warning method based on fine risk evaluation and hierarchical advanced forecast is proposed. Water inrush is a complex dynamic coupling factors system, the relationship between influencing factors and water inrush is strongly nonlinear. Therefore, the efficacy coefficient model, which has the advantages of standardization, conciseness, and freedom from subjective factors, is improved nonlinearly. The fine risk evaluation theory and method based on the improved efficacy coefficient model consisted of two parts: one is static evaluation used in design stage, and the other is dynamic evaluation applied in the construction stage. The index weights are determined scientifically and reasonably by Analytical Hierarchy Process (AHP) and the entropy method. According to the fine risk evaluation results, combined with the advantages and disadvantages of various forecasting methods, a multistep hierarchical detection method of disaster resources for water inrush is proposed to identify the occurrence characteristics and failure level of disaster sources. The theory has been successfully applied to the #3 inclined well of Yuelongmen Tunnel in Cheng-Lan Railway. The evaluation results had good agreement with the actual excavation data, which indicates that the model is of high credibility and feasibility. The method could improve the prediction accuracy of water inrush and explore geometric characteristics and filling of disaster-causing structures. It is of great significance for avoiding water inrush and guiding the rapid and safe tunnel construction.

Highlights

  • According to the national strategy layout of “One Belt and One Road”, more and more tunnels will be built in the western mountain areas of China with developed karst, rich groundwater and surface water, and extremely complex geological conditions

  • In order to realize the accurate prediction of water inrush risk in karst tunnels, a new risk evaluation theory and method based on improved efficacy coefficient model was proposed

  • By comparing the results evaluated by the improved efficacy coefficient method with those of fuzzy mathematics, attribute mathematics, and extension theory, the results showed that good application effects had been achieved (Table 9)

Read more

Summary

Introduction

According to the national strategy layout of “One Belt and One Road”, more and more tunnels will be built in the western mountain areas of China with developed karst, rich groundwater and surface water, and extremely complex geological conditions. A number of scholars have carried out research on water and mud inrush Their focus of early warning was mainly on risk evaluation and advanced prediction. Geosciences 2019, 9, 392 method of water inrush risk based on the attribute synthetic model in karst tunnels. Advanced geological prediction is a common method to realize the early warning of water inrush. In light of the above problems, an early warning method based on fine risk evaluation and hierarchical advanced forecast was established. The improved efficacy coefficient model was introduced into the fine risk evaluation of water inrush in a tunnel. According to the evaluation results and characteristics of various forecasting methods, the multi-step hierarchical advanced prediction method was established to realize fine exploration and decision-making for disaster-causing structures

Improved Efficacy Coefficient Method
Efficacy Coefficient Value of Single Index
Multi-Index Efficacy Coefficient Value
Risk Grade Recognition
Combination Weight
Entropy Method
Fine Risk Evaluation Method of Water inrush
Static Evaluation
Disaster-Related Environmental Factors
Dynamic Evaluation
Disaster-Causing factors
Grade Criteria for Disasters-Causing Factors
Regional Refined Advanced Forecast Methods
Advance Geological Forecast Method for Tunnel
Multistep Hierarchical Advance Forecast Method
Risk Aversion Criteria for Water Inrush
Engineering Application
Dynamic Risk Evaluation Result
Conventional Advance Forecast Method
Advance Borehole Drilling Method
PEER m toREVIEW
Conclusions
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.