浅埋偏压连拱隧道施工数值模拟分析

On numeric simulation analysis of construction of shallow and unsymmetrical double-arch tunnel

针对浅埋偏压连拱隧道,采用中导洞施工方法,对浅埋偏压连拱隧道的两种不同施工顺序(先挖深侧后挖浅侧或先挖浅侧再挖深侧)进行数值模拟,分析两种不同施工顺序下围岩应力、位移,中墙应力、位移及初期支护内力、位移的变化值,得出"先浅后深"施工顺序优于"先深后浅"施工顺序。

Based on the features of the shallow and unsymmetrical double-arch tunnel, the paper adopts the middle heading method to undertake the numeric simulation of the shallow and unsymmetrical double-arch tunnel in two difference orders, which include the excavation of the shallow side is followed by the excavation of the deep one and the excavation of the deep side by the excavation of the shallow one, analyzes the surround- ing rock stress, the displacement, the stress of the middle wall, the displacement and the primary support internal stress, and the changing value of the displacement in the two construction orders, and concludes the construction order of the shallow excavation followed by the deep one is su- perior to the order of the deep excavation followed by the shallow one.