北京交通大学学报2024，Vol.48Issue(1)：44-53,10.DOI:10.11860/j.issn.1673-0291.20230060
300 m2级5车道隧道九硐室施工力学特性数值计算
Numerical calculation of mechanical characteristics during construction of nine chambers in a 300 m2 class 5-lane tunnel
摘要
Abstract
This paper investigates the construction technology and structural stress of a 300 m2, 5-lanesuper-large section tunnel involved in the Baopeng large underground interchange on Qiaocheng East Road in Shenzhen. Firstly, a construction technique for excavating nine chambers in a super-large sec-tion tunnel is proposed, involving sub-chamber excavation+reinforced lining support. Subsequently, utilizing tunnel geometry and support schemes, a three-dimensional finite element numerical calcula-tion model is established in Midas to explore the dynamic mechanical response characteristics of the ex-cavation construction for the 5-lane super-large section tunnel. Finally, stress cloud maps for each sub-section structure of the tunnel are extracted, and statistical analysis is conducted on the stress and dis-placement monitoring curves of characteristic measurement points. The research results indicate the need for advanced measures, such as small conduits and grouting within the pipe shed, to pre-reinforce the surrounding rock during the construction period. On site, a nine-chamber excavation method involv-ing double-sided wall guide pits and double temporary horizontal braces is required. Additionally, a sup-port scheme comprising double-layer initial support+reinforced thickened secondary lining support is ad-opted. After on-site excavation and construction, structural stress and displacement exhibit a rapid in-creasing trend, followed by the continuous forward movement of the tunnel face, eventually leading to the stabilization of the curves. The surrounding rock's peak pressure can reach 2.01 MPa. At the arch crown position, the maximum internal force of the leading small conduit is 10 kN, the maximum internal force of the pipe shed at the two sides of the arch waist position is 20 kN, the maximum internal force of the steel arch frame at the arch waist and arch foot positions is 113 kN, and the internal force of the lock-ing anchor rod at the arch shoulder position reaches 18 kN in the 66th excavation construction step. The peak stress at the measuring point of the initial support structure is 2.4 MPa, and the settlement peak val-ues at the initial support arch crown and arch shoulder are 12.4 mm and 6.8 mm, respectively. The com-bined support effect of the pipe shed, locking anchor rod, and other structures is significant.关键词
地下互通式立交/5车道隧道/双侧壁导坑+双临时横撑/双层初支/动态响应Key words
underground interchange/5-lane tunnel/double-sided wall heading+double temporary transverse braces/double-layer initial support/dynamic response分类
交通运输引用本文复制引用
王星,黄帅,王帅帅,霰建平,葛国库..300 m2级5车道隧道九硐室施工力学特性数值计算[J].北京交通大学学报,2024,48(1):44-53,10.基金项目
国家自然科学基金(52278328) （52278328）
中交第二公路工程局科技研发项目(GHTJ-07-QT-046)National Natural Science Foundation of China(52278328) （GHTJ-07-QT-046）
Scientific and Technological Research and Development Project of CCCC Second Highway Engineering Co.,Ltd.(GHTJ-07-QT-046) （GHTJ-07-QT-046）
