上覆流沙层浅埋暗挖隧道开挖技术研究

Research on the Excavation Technology of Shallow Buried and Undercut Tunnels Covered with Quicksand

以西安地铁某出入口覆土较浅且存在流沙层的暗挖隧道开挖为背景,研究浅埋暗挖法施工技术措施,系统地分析了浅埋暗挖法施工要点、存在的风险以及改进管棚布设、优化小导管、修正开挖步序等综合措施,经监测分析,地表以及管线累计沉降均在可控范围内,可保证上覆流沙层浅埋暗挖通道开挖安全,对类似地质风险的暗挖隧道施工具有一定的借鉴指导意义。

Based on the excavation of a tunnel with shallow earth cover and quicksand layer at an entrance and exit of Xi’an subway, this paper studies the construction technical measures of the shallow underground excavation method, systematically analyzes the construction key points and risks of the shallow underground excavation method, as well as the comprehensive measures such as improving the pipe shed layout,optimizing the small conduit, and revising the excavation sequence. Through monitoring and analysis, the accumulated settlement of the surface and pipelines are within the controllable range, which can ensure the excavation safety of the shallow underground excavation channel covered with quicksand layer, and has certain reference and guiding significance for the construction of underground tunnels with similar geological risks.