Principle and engineering practice of active reinforcement for initial support of soft rock tunnels

CHEN Li-jun; CHEN Jian-xun; GAO Jian-feng; WANG Wan-ping; YANG Bao-dong; GUO Hui-jie

doi:10.19818/j.cnki.1671-1637.2025.04.006

Volume 25 Issue 4

Aug. 2025

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CHEN Li-jun, CHEN Jian-xun, GAO Jian-feng, WANG Wan-ping, YANG Bao-dong, GUO Hui-jie. Principle and engineering practice of active reinforcement for initial support of soft rock tunnels[J]. Journal of Traffic and Transportation Engineering, 2025, 25(4): 80-93. doi: 10.19818/j.cnki.1671-1637.2025.04.006

Citation:

CHEN Li-jun, CHEN Jian-xun, GAO Jian-feng, WANG Wan-ping, YANG Bao-dong, GUO Hui-jie. Principle and engineering practice of active reinforcement for initial support of soft rock tunnels[J]. Journal of Traffic and Transportation Engineering, 2025, 25(4): 80-93. doi: 10.19818/j.cnki.1671-1637.2025.04.006

Citation:

CHEN Li-jun, CHEN Jian-xun, GAO Jian-feng, WANG Wan-ping, YANG Bao-dong, GUO Hui-jie. Principle and engineering practice of active reinforcement for initial support of soft rock tunnels[J]. Journal of Traffic and Transportation Engineering, 2025, 25(4): 80-93. doi: 10.19818/j.cnki.1671-1637.2025.04.006

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Principle and engineering practice of active reinforcement for initial support of soft rock tunnels

doi: 10.19818/j.cnki.1671-1637.2025.04.006

1.
School of Highway, Chang'an University, Xi'an 710064, Shaanxi, China
2.
CCCC First Highway Consultants Co., Ltd., Xi'an 710075, Shaanxi, China
3.
3rd Engineering Co., Ltd., China Railway 21st Bureau Group, Xianyang 712000, Shaanxi, China

Funds:

National Key R&D Program of China 2024YFB2606100

Key Project of National Natural Science Foundation of China 41831286

More Information

Corresponding author: CHEN Jian-xun (1969-), male, professor, PhD, chenjx1969@chd.edu.cn
Received Date: 2024-07-24
Accepted Date: 2025-03-06
Rev Recd Date: 2025-02-16
Publish Date: 2025-08-28

Abstract

Abstract

The common deformation and failure modes and causes of initial support in large deformation tunnels in soft rocks were summarized. The shortcomings of small-pipe grouting reinforcement in the treatment of large deformation in soft rock tunnels were pointed out. The application of small-diameter prestressed reinforcing anchor cables (referred to as reinforced anchor cables) was proposed for the reinforcement of key parts of initial support in soft rock tunnels. The active reinforcement principle, method, and effect of reinforced anchor cables were analyzed through theoretical and numerical calculations. Based on the engineering background of a typical large deformation tunnel in soft rocks, a reinforcement design and application research of reinforced anchor cables were carried out to quickly and actively reinforce the key parts of the initial support. According to research results, due to factors such as the attitude of the surrounding rock, construction disturbance, excavation span and height, large deformation tunnels in soft rocks tend to see deformation and failure in the initial support arch crown, arch waist, side walls, emergency parking belt ends, and areas near the intersection of main tunnel and transverse tunnel, which are key parts that need to be reinforced. Reinforced anchor cables utilize the displacement rate differences between the initial support surface and the interior of the surrounding rock to anchor the initial support to a relatively stable rock. The application of pre-tensioning forces of reinforced anchor cables can quickly reduce the bending moments of the hazardous cross-section of initial support, while providing active support forces to the surrounding rock. Reinforced anchor cables enhance the constraint conditions of key parts of initial support and improve the bearing capacity of the initial support for subsequent additional loads. It is not necessary for the pre-tensioning force of reinforced anchor cables to go as high as possible. The value is recommended to be 100-300 kN. The reinforced anchor cables have achieved rapid and active reinforcement of the initial support structure, with ideal application results.
- tunnel engineering,
- soft rock,
- theoretical and numerical calculation,
- large deformation,
- initial support,
- active reinforcement

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References(34)

References

[1]	CHEN Jian-xun, CHEN Li-jun, LUO Yan-bin, et al. Mechanism and control method of large deformation for large-span chlorite schist tunnel[J]. Journal of Traffic and Transportation Engineering, 2021, 21(2): 93-106. doi: 10.19818/j.cnki.1671-1637.2021.02.008
[2]	XU Jin-hua, ZHOU Hua-qiu, XIONG Wen-wei, et al. Mechanical characteristics of lining structure under different blocking conditions of drainage system of Karst tunnel[J]. Journal of Chang'an University (Natural Science Edition), 2024, 44(1): 91-104.
[3]	DENG Hai-peng, LIU Quan-sheng. Study on meter-level large deformation mechanism of soft rock mass around tunnel with high in-situ stress[J]. China Journal of Highway and Transport, 2023, 36(8): 225-239.
[4]	LIU W W, CHEN J X, LUO Y B, et al. Deformation behaviors and mechanical mechanisms of double primary linings for large-span tunnels in squeezing rock: a case study[J]. Rock Mechanics and Rock Engineering, 2021, 54(5): 2291-2310. doi: 10.1007/s00603-021-02402-5
[5]	ZHANG De-hua, LEI Ke, TAN Zhong-sheng, et al. Field test on bearing and deformation properties of double primary layers applied to large deformation tunnel in weak rock[J]. China Civil Engineering Journal, 2017, 50(S2): 86-92.
[6]	CHEN Jian-xun, LIU Wei-wei, CHEN Li-jun, et al. In-situ experimental study on large-deformation control and reasonable support forms for a large-span highway tunnel in chlorite schist[J]. China Journal of Highway and Transport, 2020, 33(12): 212-223.
[7]	FU Zhi-peng, LI Bo-rong, XU Chen, et al. Field experiment on large deformation control scheme of high stress soft rock tunnel[J]. Journal of Chang'an University (Natural Science Edition), 2023, 43(1): 133-142.
[8]	ZHANG Li-xin, CHEN Li-jun, CHEN Jian-xun, et al. Deformation characteristics and treatment measures of tunnels in soft and hard interbedded surrounding rock with tilted stratum[J]. Journal of Architecture and Civil Engineering, 2021, 38(6): 186-196.
[9]	WANG Jun-jie, ZHANG Shuai. Research on large deformation control of tunnel surrounding rock based on advance stress release and grouting reinforcement[J/OL]. Journal of Southwest Jiaotong University, 2024-04-18. http://kns.cnki.net/kcms/detail/51.1277.U.20240417.0850.002.html.
[10]	LI Wen-jiang, SUN Ming-lei, ZHU Yong-quan, et al. Arch springing stability and its control techniques during construction of tunnels with weak surrounding rocks by bench cut method[J]. Chinese Journal of Rock Mechanics and Engineering, 2012, 31(S1): 2729-2737.
[11]	XIA Run-he, CUI Xiao-peng, ZHOU Quan. Analysis of tunnel lining deformation in complex geology and engineering control technology[J]. Journal of Railway Engineering Society, 2015, 32(8): 66-72.
[12]	LIU W W, CHEN J X, CHEN L J, et al. A rational construction method and deformation control system of tunnelling in extremely soft and fractured chlorite schist medium[J]. Tunnelling and Underground Space Technology, 2024, 143: 105472. doi: 10.1016/j.tust.2023.105472
[13]	CHEN L J, CHEN J X, LI Y, et al. Performance of tunnel feet-lock pipe (TFP) in sharing vertical foundation load[J]. KSCE Journal of Civil Engineering, 2021, 25(3): 1086-1094. doi: 10.1007/s12205-021-1017-6
[14]	CHEN Jian-xun, CHEN Li-jun, LUO Yan-bin, et al. On-site testing of strain of feet-lock pipe and its restraining effect on tunnel feet in soft rock[J]. China Journal of Highway and Transport, 2023, 36(11): 218-230.
[15]	ZAN Wen-bo, LAI Jin-xing, CAO Xiao-yong, et al. Mechanical deformation characteristics of support system for boulder-cobble tunnel[J]. Journal of Traffic and Transportation Engineering, 2023, 23(4): 205-217. doi: 10.19818/j.cnki.1671-1637.2023.04.015
[16]	LAI Hong-peng, ZHAO Ming-kun, LIU Yu-yang, et al. Dynamic mechanism of surrounding rock and support of large-section tunnel passing through soft-plastic loess layer based on measured data[J]. Journal of Traffic and Transportation Engineering, 2023, 23(1): 115-131. doi: 10.19818/j.cnki.1671-1637.2023.01.009
[17]	ZHAO Dong-ping, WANG Lu-wei, YU Yu, et al. Research status and development direction of tunnel system bolt[J]. China Civil Engineering Journal, 2020, 53(8): 116-128.
[18]	LI Yan-zong, YOU Xian-ming, ZHAO Shuang. Study of deformation control scheme of breakthrough section of soft rock Muzhailing Tunnel on Lanzhou-Chongqing Railway with extremely high ground stress[J]. Tunnel Construction, 2017, 37(9): 1146-1152.
[19]	LIU Zhi-qiang, ZHU Jian-lin, WU Jian, et al. Adaptability analysis of layered primary supports for tunnels with large extrusion deformations[J]. Tunnel Construction, 2023, 43(1): 131-140.
[20]	KONG Chao, ZHANG Jun-ru, WANG Hai-yan, et al. Study on deformation characteristics and bearing mechanism of support in large deformation tunnel with deep buried soft rock[J]. China Railway Science, 2021, 42(6): 103-111.
[21]	LUO Ji-wei, ZHANG Ding-li, FANG Qian, et al. Combined support mechanism of pretensioned rock bolt and anchor cable for super-large-span tunnel[J]. China railway science, 2021, 42(6): 103-111.
[22]	HAO Dao-ming, LI Yao. Characteristics and control technology of large deformation of surrounding rock in Mengbishan tunnel[J]. Tunnel Construction, 2023, 43(S2): 535-543.
[23]	XIANG Long, LIN Guo-jin, YU Tao, et al. Control and support technology for large extrusion deformation in steep rock strata of Shengli Village tunnel[J]. Tunnel Construction, 2023, 43(S2): 406-417.
[24]	WANG Fang-tian, SHANG Jun-jian, ZHAO Bin, et al. Strengthened anchor cable support mechanism and its parameter optimization design for roadway's dynamic pressure section[J]. Journal of China University of Mining & Technology, 2022, 51(1): 56-66.
[25]	WANG Fang-tian, SHANG Jun-jian, ZHAO Bin, et al. Surrounding rock structural characteristics and anchor-cable strengthened support technology of the gob-side entry retaining with roof cutting and pressure releasing[J]. Chinese Journal of Rock Mechanics and Engineering, 2021, 40(11): 2296-2305.
[26]	HE Man-chao, REN Shu-lin, TAO Zhi-gang. Disaster prevention and control methods for deep buried tunnels[J]. Journal of Engineering Geology, 2022, 30(6): 1777- 1797.
[27]	TAO Zhi-gang, LUO Sen-lin, LI Meng-nan, et al. Optimization of large deformation control parameters of layered slate tunnels based on numerical simulation and field test[J]. Chinese Journal of Rock Mechanics and Engineering, 2020, 39(3): 491-506.
[28]	WANG Bo, YU Wei, ZI Xin, et al. Rationality of various support types of Muzhailing highway tunnel in soft rocks with large deformation[J]. Tunnel Construction, 2023, 43(1): 36-47.
[29]	CHEN Li-jun, CHEN Jian-xun, GUO Hui-jie, et al. Reinforcement effect of small-diameter prestressed anchor cables on the surrounding rock of soft rock tunnels[J]. China Journal of Highway and Transport, 2025, 38(1): 224-237.
[30]	CHEN Li-jun, CHEN Jian-xun, GUO Hui-jie, et al. A new method for controlling convergence deformation at arch feet of initial support in soft rock tunnels[J]. China Journal of Highway and Transport, 2025, 38(6): 246-257.
[31]	CHEN Li-jun, CHEN Jian-xun, GUO Hui-jie, et al. The concept and technological implementation of active control for foot settlement of soft rock tunnels[J]. Chinese Journal of Rock Mechanics and Engineering, 2025, 44(6): 1466-1480.
[32]	GUO Hui-jie, CHEN Li-jun, ZHANG Li-xin, et al. Deformation characteristics and reinforcement methods in variable cross-section at emergency parking belt in soft rock mass highway tunnel[J]. Science Technology and Engineering, 2022, 22(35): 15765-15774.
[33]	CAI Shu-yao. Design method and application of prestressed anchorage system based on displacement difference in soft rock tunnel with large deformation[D]. Chengdu: Southwest Jiaotong University, 2021.
[34]	HETENYI M. Beams on elastic foundation: theory with applications in the fields of civil and mechanical engineering[M]. Ann Arbor: The University of Michigan Press, 1946.

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Principle and engineering practice of active reinforcement for initial support of soft rock tunnels

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