Assessment of tunnel face stability subjected to an adjacent tunnel. (January 2021)

• Record Type: Journal Article
• Authors: Feng, Liuyang; Zhang, Limao
• Is Part Of: Reliability engineering & system safety. Volume 205(2021)
• Publication Date: 2021-01
• Subjects: Reliability of tunnel excavation -- Limit support pressure -- Copula function -- Intelligent approach -- Incomplete information; Reliability (Engineering) -- Periodicals; System safety -- Periodicals; Industrial safety -- Periodicals; Fiabilité -- Périodiques; Sécurité des systèmes -- Périodiques; Sécurité du travail -- Périodiques; 620.00452
• DOI: 10.1016/j.ress.2020.107228
• Languages: English
• ISSNs: 0951-8320

Abstract

Highlights: A meta-model is developed for the limit support pressure (LSP) of the tunnel excavation face. The trivariate copula is constructed for modeling soil properties under incomplete information. Copula-based simulation is developed for estimating LSP probability distribution. A new index is proposed to quantify the copula's effect for forty-six illustrative cases. Reliability of the tunnel excavation system is benchmarked using different existing formulas. Abstract: This paper conducts a reliability assessment of the tunnel face stability induced by an adjacent tunnel under incomplete information. The evaluation indicator in this study is the limit support pressure (LSP) for the tunnel excavation face, which is first determined through a detailed finite element analysis. Relying on the numerical results, a hybrid particle swarm optimization-neural network (PSO-NN) is developed to construct the meta-model for LSP. This study develops a framework of Monte Carlo simulation combing with the trivariate copula analysis of the cohesive strength, Poisson ratio, and internal friction angle, to assess the probability distribution of LSP with incomplete information. This study proposes an index α greater than 1.0, to quantify the copula's effect in forty-six illustrative cases. Finally, this paper examines the reliability of different existing formulas of LSP in the tunneling excavation procedure. Rankine and Terzaghi's formulas show a higher reliability value above 0.8. Furthermore, this study proposes a new safety factor for engineering design considering the uncertainties and copula's effect. Through further examining the performance of the new safety factor based on the Rankine and Terzaghi approaches, this study proposes a new procedure to determine LSP for a safe and efficient engineering design practice.