摘要
针对隧道施工效率低和材料浪费问题,以张掖抽水蓄能电站1号场内公路隧道为研究对象,采用单层衬砌作为原复合式衬砌的优化结构,并通过室内试验设计抗渗混凝土;基于数值仿真对单层衬砌方案的可行性进行验证;提出单层衬砌现场施工流程,并在现场应用。研究发现:当C30混凝土防水剂掺量为胶凝材料的2%时,混凝土拌合物黏聚性、包裹性良好,工作性能较好,满足单层衬砌喷射混凝土在隧道长期使用功能;隧道支护为单层衬砌后,围岩的拱顶沉降为5.90mm,仰拱隆起为10.38mm,水平收敛最大值为1.21mm,围岩变形较小;初期支护压应力最大值为9.60MPa,位于边墙附近,拉应力最大值为0.06MPa,位于拱顶处,两者均小于容许应力值,结构安全;砂浆锚杆均为拉应力,小于极限拉力值,锚杆安全;围岩拱腰和拱脚附近产生剪切破坏塑性区,底板局部产生受拉塑性区,总体区域较小,围岩较稳定,单层衬砌方案具有可行性。
To improve tunnel construction efficiency and reduce material waste,the Zhangye Pumped-Storage Power Station No.1 Access Road Tunnel was selected as the research subject.A single-layer lining was adopted as an optimization of the original composite lining,and waterproof concrete was designed through laboratory testing.The feasibility of the single-layer lining scheme was verified through numerical simulation,and a field construction process for the single-layer lining was proposed.The study found that:the indoor mix ratio reached the test strength after 3 days,and the strength increased compared to the control group after adding 2%waterproofing material;After the tunnel lining cross-section was changed to a single-layer shotcrete lining,the arch settlement of the surrounding rock was 5.90 mm,the invert arch uplift was 10.38 mm,and the maximum horizontal convergence was 1.21 mm,with relatively small deformation of the surrounding rock.The maximum initial support compressive stress was 9.60 MPa,located near the side walls,and the maximum tensile stress was 0.06 MPa,located at the arch crown.Both values were below the allowable stress limits,ensuring structural safety;All mortar anchor bolts are under tensile stress,which is below the ultimate tensile strength value,ensuring anchor bolt safety;Shear failure plastic zones have formed near the arch crown and arch foot of the surrounding rock,and local tensile plastic zones have formed on the floor slab.The overall affected area is small,indicating stable surrounding rock conditions,which validates the feasibility of the single-layer lining scheme.A field construction process for the single-layer lining has been designed.
作者
丁万钦
王文东
张嘉辉
万臣
杨卫峰
龙潭
张俊儒
范子焱
DING Wanqin;WANG Wendong;ZHANG Jiahui;WAN Chen;YANG Weifeng;LONG Tan;ZHANG Junru;FAN Ziyan(China Yangtze Power Co.,Ltd.,Beijing 100035;China Three Gorges Construction Engineering Corporation,Beijing 100035;China Railway 12th Bureau Group Co.,Ltd.,Taiyuan 030024;Southwest Jiaotong University,Chengdu 610031)
出处
《现代隧道技术》
北大核心
2025年第S1期365-375,共11页
Modern Tunnelling Technology
基金
中国三峡建工(集团)有限公司项目基金(KJCX202500045)
关键词
单层衬砌
支护方案
优化
数值模拟
施工方法
Single-layer lining
Support scheme
Optimization
Numerical simulation
Construction method
