摘要
为探明施工隧道穿越断层破碎带时,何种断层形态对围岩稳定性影响最为显著,以绵九高速公路五里坡隧道不同断层形态为例,采用三因素四水平正交数值模拟试验,对围岩进行敏感性分析。此外,为保证隧道施工过程安全,分析断层的响应特性,断层段需围岩注浆加固提高其稳定性。对注浆加固圈厚度分别为:0、1、2、3 m的断层段隧道施工过程进行FLAC 3D三维模拟,采用位移控制率均值K对隧道断层及前后段整个区段的围岩控制效果进行定量评价。结果表明:断层倾向在各水平条件下变化时,拱顶沉降和边墙位移基本不发生改变,其余两因素对隧道拱顶沉降和边墙位移的影响程度分别为:断层厚度>断层倾角、断层倾角>断层厚度。注浆加固圈厚度由0 m递增至3 m时,隧道轴向位移和塑性区面积依次减少,但注浆加固效果也明显下降。通过围岩位移控制率k定量分析注浆加固对位移的控制效果,断层前后段的位移控制率均小于断层处。加固圈为2 m效果最好。
In order to find out which fault shape has the most significant influence on the stability of surrounding rock when the construction tunnel passes through the fault fracture zone,the sensitivity analysis of surrounding rock was carried out by using three factors and four levels orthogonal numerical simulation test with different fault shapes of Wulipo Tunnel of Mianyang-Jiujiang Expressway as an example.In addition,in order to ensure the safety of the tunnel construction process and analyze the response characteristics of the fault,the fault section needs surrounding rock grouting to improve its stability.FLAC 3D simulation was carried out for the tunnel construction process in the fault section with grouting reinforcement ring thickness of 0,1,2,3 m respectively,and the control effect of surrounding rock in the tunnel fault and the whole section before and after the tunnel was quantitatively evaluated by using the average displacement control rate K.The results show that when the fault tendency changes under various horizontal conditions,the vault settlement and side wall displacement basically do not change,and the other two factors affect the tunnel vault settlement and side wall displacement as follows:fault thickness>fault dip angle,fault dip angle>fault thickness.When the thickness of grouting reinforcement ring increases from 0 m to 3 m,the axial displacement and plastic area of the tunnel decrease in turn,but the grouting reinforcement effect also decreases significantly.The control effect of grouting reinforcement on displacement is quantitatively analyzed by the displacement control rate k of surrounding rock,and the displacement control rate of the front and rear segments of the fault is less than that of the fault.The reinforcement ring of 2 m is the best.
作者
章玉伟
徐泽鑫
谢远
邱军领
杨桃
谢永利
ZHANG Yu-wei;XU Ze-xin;XIE Yuan;QIU Jun-ling;YANG Tao;XIE Yong-li(Shudao Investment Group Co.,Ltd.,Chengdu 610000,China;School of Highway,Chang an University,Xi'an 710064,China;Sichuan Dujinshandi Railway Transportation Co.,Ltd.,Chengdu 610023,China;China Railway First Survey and Design Institute Group Ltd.,Xi'an 710043,China;Sichuan Shudao New System Rail Group Co.,Ltd.,Chengdu 610023,China)
出处
《科学技术与工程》
北大核心
2023年第8期3493-3501,共9页
Science Technology and Engineering
基金
四川都金山地轨道交通有限责任公司项目(2020-1)。
关键词
隧道
断层破碎带
围岩敏感性
正交试验
围岩稳定性
tunnel
fault fracture zone
sensitivity of surrounding rock
orthogonal test
stability of surrounding rock
