
科学技术与工程

中国技术经济学会
分层倾斜岩土大断面隧道新型让压支护结构支护效果:以兰州白塔山隧道为例
蒋春海 , 段旭晗 , 郑钊 , 张明礼 , 马昭 , 赵博
科学技术与工程 ›› 2024, Vol. 24 ›› Issue (29) :12734-12743
分层倾斜岩土大断面隧道新型让压支护结构支护效果:以兰州白塔山隧道为例
Supporting Effect of New Yielding Support Structure for Large Section Tunnel in Layered Inclined Rock and Soil: A Case Study of Lanzhou Baitashan Tunnel
为解决分层岩土地层隧道中出现的应力及变形分布不协调的问题,提出了一种针对分层岩土地层的新型支护结构,并构建了常规支护结构和新型让压支护结构的数值计算模型,对两种支护结构的支护效果进行了对比研究。结果表明:不同地层中围岩压力变化均表现为快速增长-缓慢增长-趋于稳定3个变化阶段,最终围压和变形分布均呈现出“黄土侧大,岩石侧小”的分布形态;新型让压支护结构减弱了围岩位移分布向黄土侧偏移的效果,上部导坑的围岩竖向位移和水平位移也均小于常规支护结构;新型让压支护结构拱架受力和变形整体小于常规支护结构,且降低了两侧导坑的变形差异,而缓冲让压结构的设置使分层岩土界面处支护结构受力和变形减小,实现了缓冲让压支护效果。总体上,新型让压支护结构在分层岩土地层隧道中具有良好的支护效果。
In order to solve the problem of uncoordinated stress and deformation distribution in tunnels in layered geotechnical strata, a new pressure support structure for layered geotechnical strata was proposed, and the numerical models of conventional support structure and new yielding support structure were constructed. The supporting effects of the two supporting structures were compared. The results show that the change of surrounding rock pressure in different strata is characterized by three stages: rapid growth-slow growth-stabilization. The final confining pressure and deformation distribution show the distribution pattern of "large on the loess side and small on the rock side". The new yielding support structure weakens the effect of the displacement distribution of the surrounding rock to the loess side, and the vertical displacement and horizontal displacement of the surrounding rock of the upper heading are also smaller than those of the conventional support structure. The stress and deformation of the arch support of the new yielding support structure are smaller than those of the conventional support structure. It also reduces the deformation difference between the two sides of the heading. Among them, the setting of the buffer yielding structure reduces the stress and deformation of the support structure at the layered geotechnical interface, and realizes the effect of pressure support. In general, the new yield support structure has a good supporting effect in layered rock and soil tunnel.
tunnel engineering / layered geotechnical strata / new supporting structure / deformation control
/
| 〈 |
|
〉 |