摘要
针对软岩条件下超大断面隧道施工过程中力学响应特征复杂、变形机理不明的问题,文中依托重庆张家山隧道工程,通过FLAC3D建立了精细化的三维数值模型,深入揭示软岩变截面隧道的施工力学响应规律。研究表明:变截面隧道地表沉降呈“碟形”分布,Ⅱ段对峰值沉降起主控作用;隧道拱顶沉降与拱底隆起随施工逐步累积,拱腰受扰动影响表现为先外扩后收敛;初期支护内力沿开挖方向逐渐增大,截面突变对大断面不利,对小断面相对有利。
To address the problems of complex mechanical response characteristics and unclear deformation mechanisms during the construction of super-large cross-section tunnels in soft rock,this study takes the Zhangjiashan Tunnel project in Chongqing as the engineering background.A refined three-dimensional numerical model was established using FLAC3D to systematically reveal the construction mechanical response laws of a variable cross-section tunnel in soft rock.The results show that the ground surface settlement of the variable cross-section tunnel exhibits a“dish-shaped”distribution,and SectionⅡplays a dominant role in controlling the peak settlement.The tunnel crown settlement and invert heave increase progressively during construction,while the tunnel spandrels,affected by construction disturbance,first expand outward and then converge inward.The internal forces of the primary support gradually increase along the excavation direction.Abrupt cross-section changes are unfavorable to the large cross-section section,but relatively beneficial to the small cross-section section.
作者
李俊
Li Jun(China Railway First Group Co.,Ltd.,Xi’an Shaanxi 710054,China)
出处
《山西建筑》
2026年第8期136-139,共4页
Shanxi Architecture
关键词
软岩隧道
超大断面
变截面
力学响应
soft rock tunnel
super-large cross-section
variable cross-section
mechanical response
