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陳家征^{1 , 2} ,   李   忠^1 , 2 ,  韓   煬^1 , 2

( 1 .  石家莊鐵道大學 土木學院 ，河北 石家莊 050043 ;

2.  道路與鐵道工程安全保障省部共建教育部重點實驗室 ，河北石家莊 050043)

摘   要： 由于山嶺隧道洞口段多處于淺埋偏壓地形 ，為保證施工進洞安全，常常需要采取超前支護以控制洞口段圍巖變形 ，保證圍巖穩定。以彝良隧道洞口段為工程背景 ，采用 FLAC 3D 有限差分軟件，分別建立無超前支護 、管棚超前支護 、超前小導管超前支護和管棚 ＋超前小導管聯合超前支護方案進行比選分析。計算結果表明：超前支護可大幅度降低圍巖豎向位移 、水平位移 、豎向應力以及抑制拱頂塑性區發育 ；從支護效果上看， 管棚支護效果最佳 ，管棚＋超前小導管聯合支護次之 ，超前小導管最差 ；從管棚長度自身以及施工經濟合理性考慮 ，在控制圍巖變形效果相當的條件下 ，采用管棚 ＋超前小導管聯合支護較佳。研究可為類似淺埋偏壓隧道  洞口段超前支護方式的選擇提供借鑒。

關鍵詞：淺埋偏壓隧道 ；超前支護 ；管棚 ；超前小導管 ；數值模擬

中圖分類號：U455 . 7           

文獻標志碼：A            

文章編號： 1005- 8249  (2024)  04- 0059- 08 

DOI:10. 19860/j.cnki.issn1005 - 8249.2024.04.011

CHEN Jiazheng^{1 , 2}  ,   LI Zhong^{1 , 2}  ,  HAN Yang^{1 , 2}

( 1 . School of Civil Engineering ,   Shijiazhuang Tiedao University ,   Shijiazhuang 050043 ,   China;

2. The Ministry of Education Jointly Established the Key Laboratory of Road and Railway Engineering

Safety and Security ,  Shijiazhuang 050043 ,   China)

Abstract: Due to the portal section of mountain tunnel is mostly located in the shallow buried and unsymmetrical pressure terrain, in order to ensure the safety of tunnel entry, advance support is often required to control the deformation of surrounding rock at the portal section and ensure the stability of surrounding rock. Taking the portal section of Yiliang Tunnel as the engineering background, the FLAC 3D finite difference software is used to establish no advance support, only pipe shed advance support, only advance small pipe advance support and pipe shed+advance small pipe combined advance support schemes for comparison and analysis. The calculation results show that the advance support can greatly reduce the vertical displacement, horizontal displacement, vertical stress of surrounding rock and inhibit the development of the plastic zone of arch crown. From the perspective of the support effect, the pipe shed support is the best, followed by the pipe shed+advance small conduit combined support, and the advance small conduit is the worst. Considering the length of pipe shed and the economic rationality of construction, under the condition that the effect of controlling the deformation of surrounding rock is equivalent, it is better to use pipe shed+advance small conduit combined support. The study can provide theoretical guidance for the selection of advance support methods for similar shallow buried tunnel portal section under eccentric pressure.

Keywords :  shallow buried bias tunnels;  advance support;  pipe shed;  advance small conduit;  numerical simulation

作者簡介： 陳家征  (1998—) ,  男 ，碩士 ，研究方向：地質災害超前預報及隧道地下工程。

通信作者：李忠  (1968—) ,  男 ，博士 ，教授 ，研究方向：地質災害超前預報及隧道地下工程。

收稿日期：2022- 12- 31