Damage characteristics of intercalary rock in bifurcated tunnel under alternate blasting excavation

被引：0

作者：

Yang H. ^{[1
]}

Yu J. ^{[1
]}

Fu X. ^{[1
,2
]}

Yao W. ^{[1
]}

Lin C. ^{[1
]}

Chang F. ^{[1
]}

机构：

[1] Fujian Provincial Technology Research Center for Tunneling and Urhan Underground Space Engineering, Huaqiao University, Xiamen

[2] School of Civil Engineering, Sanming University, Sanming

来源：

Zhendong yu Chongji/Journal of Vibration and Shock | 2023年 / 42卷 / 01期

关键词：

bifurcated tunnel; blasting load; damage distribution; intercalary rock; rock mass damage;

D O I：

10.13465/j.cnki.jvs.2023.01.006

中图分类号：

学科分类号：

摘要：

Clarifying intercalary rock damage laws in bifurcated small net spacing tunnels under working condition of alternate blasting excavation is helpful to better ensure onsite construction of tunnels and stability of surrounding rock. Here, the 3-D finite difference software FLAC was used to simulate alternate excavation processes of bifurcated tunnels with small net spacing under action of blasting load, and damage distribution and evolution laws of intercalary rock under different excavation conditions were mainly studied. Finally, the onsite acoustic wave damage range detection results of Xiamen Haicang Port dredging channel bifurcated tunnel project were used to verify the simulation results. The study showed that stress wave generated by blast is reflected at bifurcation to form tensile stress to make section damage at bifurcation more serious; damage of intercalary rock in tunnel reveals an asymmetric "V" distribution, and damage gradually increases from inside of intercalary rock to contour line, the maximum damage of intercalary rock at main tunnel side is in the range of 90° - 120°, and the maximum damage of intercalary rock at ramp side is in the range of 90° ; thickness of intercalary rock has a larger impact on its damage, with increase in thickness, damage degree of intercalary rock decreases and damage range does not penetrate left and right tunnels; compared with 2 m footage, the complete damage area of 5 m footage increases by 58. 5%, damage penetration area increases by 70% ; the complete damage area of 1-step offset increases 1. 27 m compared with 4-step offset, and the damage penetration range also increases to a certain extent; excavating a smaller section firstly is conducive to stability of intercalary rock, and the damage symmetry of surrounding rock is better, but rock mass damage far away from intercalary rock can expand; the numerical simulation results are basically consistent with the onsite measurement results, the simulation results can provide a certain reference for constructing bifurcated small net spacing tunnels of highway. © 2023 Chinese Vibration Engineering Society. All rights reserved.

引用

页码：46 / 53and88

页数：5342

共 23 条

[1] LI C J, LI X B., Influence of wavelength-to-tunnel-diameter ratio on dynamic response of underground tunnels subjected to blasting loads, International Journal of Rock Mechanics and Mining Sciences, 112, pp. 323-338, (2018)
[2] LUO Sheng, YAN Peng, LU Wenbo, Et al., Research on the simulation of blasting damage and its mechanism of deep tunnel excavation, Chinese Journal of Rock Mechanics and Engineering, 40, pp. 2760-2772, (2021)
[3] MOHAMED M, AZRUL M, ROSZILAH H, Et al., Blast damage assessment of symmetrical box-shaped underground tunnel according to peak particle velocity (PPV) and single degree of freedom (SDOF) criteria, Symmetry, 10, 5, (2018)
[4] SONG Xiaolong, GAO Wenxue, JI Jinming, Et al., Influence of blasting vibration on cumulative damage of surrounding rock, Journal of Vibration and Shock, 39, 24, pp. 54-62, (2020)
[5] YANG Gouliang, YANG Renshu, CHE Yulong, Damage accumulative effect of surrounding rock under periodic blasting vibration [J], Journal of China Coal Society, 38, pp. 25-29, (2013)
[6] YANG J H, JIANG Q H, ZHANG Q B, Et al., Dynamic stress adjustment and rock damage during blasting excavation in a deep-buried circular tunnel [J], Tunnelling and Underground Space Technology, 71, pp. 591-604, (2018)
[7] YANG Jianghua, LU Wenbo, HU Yinguo, Et al., Accumulated damage in surrounding rocks due to repeated blasting loads during blasting excavation of tunnels, Rock Soil Mech, 35, 2, pp. 511-518, (2014)
[8] JI Ling, ZHOU Chuanbo, ZHANG Bo, Et al., Study on dynamic response and damage effect of surrounding rock in large tunnel under blasting excavation, Journal of the China Railway Society, 43, 7, pp. 161-168, (2021)
[9] CAO Feng, LING Tonghua, LI Jie, Et al., Cumulative damage feature analysis for shared rock in a neighborhood tunnel under cyclic explosion loading, Journal of Vibration and Shock, 37, 23, pp. 141-148, (2018)
[10] LIU Minlong, CHEN Shihai, SUN Jie, Et al., Detection and numerical simulation of blasting-induced damage in shallow-buried twin tunnels with small spacing, Explosion and Shock Waves, 41, pp. 149-157, (2021)

← 1 2 3 →