Support pressure assessment for deep buried railway tunnels using BQ-index

基于BQ 指标的深埋铁路隧道支护压力评估方法

Abstract

Estimation of support pressure is extremely important to the support system design and the construction safety of tunnels. At present, there are many methods for the estimation of support pressure based on different rock mass classification systems, such as Q system, GSI system and RMR system. However, various rock mass classification systems are based on different tunnel geologic conditions in various regions. Therefore, each rock mass classification system has a certain regionality. In China, the BQ-Inex (BQ system) has been widely used in the field of rock engineering ever since its development. Unfortunately, there is still no estimation method of support pressure with BQ-index as parameters. Based on the field test data from 54 tunnels in China, a new empirical method considering BQ-Inex, tunnel span and rock weight is proposed to estimate the support pressure using multiple nonlinear regression analysis methods. And then the significance and necessity of support pressure estimation method for the safety of tunnel construction in China is explained through the comparison and analysis with the existing internationally widely used support pressure estimation methods of RMR system, Q system and GSI system. Finally, the empirical method of estimating the support pressure based on BQ-index was applied to designing the support system in the China’s high-speed railway tunnel—Zhengwan high-speed railway and the rationality of this method has been verified through the data of field test.

摘要

支护压力的评估对于支护结构系统的设计及隧道施工的安全至关重要。目前, 有较多基于不同 岩体分类系统的支护压力评估方法, 例如Q 系统, GSI 系统和RMR 系统等。但各种岩体分类系统都 是基于不同地区的隧道地质条件建立起来的。因此, 每种岩体分类系统都具有一定的区域性。自 BQ-Inex(BQ 系统)出现以来, 在中国岩石工程领域得到了广泛的应用。但是中国仍然没有以BQ 指数 为参数的支护压力评估方法。本文基于中国54 条铁路隧道的现场试验数据, 采用多元非线性回归分 析方法, 考虑隧道跨度和围岩重度, 提出了一种基于BQ 指标的支护压力经验评估方法。然后, 通过 与国际上广泛使用的RMR 系统, Q 系统和GSI 系统的支护压力评估方法的比较和分析, 阐述了建立 以BQ 指标为参数的支护压力评估方法对保证中国隧道施工安全的意义和必要性。最后, 将基于BQ 指标的支护压力经验估算方法应用于中国高速铁路隧道-郑万高铁支护系统设计中, 并通过实测数据 验证了该方法的合理性。

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Authors

Contributions

The overarching research goals were developed by WANG Ming-nian, WANG Zhi-long, TONG Jian-jun, ZHANG Xiao, DONG Yu-cang and LIU Da-gang. WANG Ming-nian and LIU Da-gang provided the test data used in this paper. WANG Zhi-long proposed the calculation method of support pressure and analyzed the calculated results. The initial draft of the manuscript was written by WANG Zhi-long. TONG Jian-jun, ZHANG Xiao and DONG Yu-cang revised the errors of the initial draft. All authors replied to reviewers’ comments and revised the final version.

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Correspondence to Da-gang Liu 刘大刚.

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Conflict of interest

WANG Ming-nian, WANG Zhi-long, TONG Jian-jun, ZHANG Xiao, DONG Yu-cang and LIU Da-gang declare that they have no conflict of interest.

Foundation item

Projects(51878567, 51878568, 51578458) supported by the National Natural Science Foundation of China; Projects(2017G007-F, 2017G007-H) supported by China Railway Science and Technology Research and Development Plan

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Wang, Mn., Wang, Zl., Tong, Jj. et al. Support pressure assessment for deep buried railway tunnels using BQ-index. J. Cent. South Univ. 28, 247–263 (2021). https://doi.org/10.1007/s11771-021-4600-6

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Key words

  • rock mass classification
  • support pressure
  • deep buried tunnel
  • field test
  • multiple nonlinear regression analysis
  • BQ-Index

关键词

  • 岩体分级
  • 支护压力
  • 深埋隧道
  • 现场测试
  • 多元非线性回归
  • BQ 指标