摘要
为研究垂直交叉隧道开挖时对现有隧道支护系统的影响,采用全三维有限元与弹塑性材料模型相结合的方法,研究了山区垂直穿越隧道间的相互作用。分析结果表明:新建隧道施工的影响下,水平应力较高的地区已有隧道喷射混凝土衬砌内侧处于受拉状态;在拱顶和仰拱处于受压状态,在离洞口地段受拉较大。新隧道掘进时顶部既有隧道锚杆的拉力减小,深埋隧洞上覆土层使现有混凝土衬砌产生压缩破坏,且在隧道顶板周围既有锚杆拉力显著增大。为保证既有隧道的稳定性,浅埋隧道优先安装时,既有喷射混凝土衬砌两侧需进行局部加厚,深埋隧道优先安装时,既有喷射混凝土衬砌顶部需进行局部加厚。
In order to research the influence of the vertically crossed tunnel excavation on the support system of the existing tunnels,the paper adopts the combined methods of the full 3-D finite element and the elastoplastic material models,researches the mutual effect of the vertically crossed tunnels in mountainous areas,shows by the analytic results that the inside of sprayed concrete block lining is in the in-tension condition in the areas with higher horizontal stress under the influence of the newly-built tunnels,while the section away from the tunnel entrance has larger stress when the arch top and inverted arch are under the stress;the stress of the top anchor bolt of the existing tunnels reduces in the process of tunneling,the covered soil of the deep-buried tunnel leads to the compression failure of the concrete lining and the existing anchor tension surrounding the tunnel roof increases obviously;in order to ensure the stability of the existing tunnels,the two sides of the existing sprayed concrete lining should be partly thickened during the optimal installation of the shallow-buried tunnel,while the top of the existing sprayed concrete lining should be partly thickened during the optimal installation of the deep-buried tunnels.
作者
汪海超
Wang Haichao(Guangzhou Urban Planning,Surveying and Designing Institute,Guangzhou Guangdong 510500,China)
出处
《山西建筑》
2024年第20期175-177,共3页
Shanxi Architecture
关键词
浅埋隧道
喷射混凝土衬砌
垂直穿越
支护系统
shallow-buried tunnel
spray concrete lining
vertical crossing
support system
