Based on the construction of Laimipo Tunnel,this paper delves into the disturbance of surrounding rock in the tunnel body of shallow-buried super-span multi-arch tunnel during construction.A construction stage model of Laimipo Tunnel was established using finite element software,and the variation characteristics during tunnel excavation were analyzed in detail from multiple aspects such as stress,displacement,and strain of the surrounding rock of the tunnel body,in order to provide reference and guidance for actual construction.The results show that after the excavation of the main tunnel,large stress mainly occurs at the arch foot,and there is stress concentration at the foot of the middle partition wall.The lateral displacement of surrounding rock is basically completed after the excavation of the left and right heading.Due to the supporting role of core soil,the vertical displacement of surrounding rock mainly occurs after the completion of core soil excavation.After the excavation of the middle guide tunnel,the large strain zone mainly appears at the bottom of the middle guide tunnel,and after the excavation of the main tunnel,the large strain zones are mainly concentrated at the arch foot,spandrel,and vault of the tunnel.Overall,the vertical strain is greater than the horizontal strain.
关键词
连拱隧道/数值模拟/围岩扰动/双侧壁导坑法
Key words
multi-arch tunnel/numerical simulation/surrounding rock disturbance/double sidewall heading method
维普
万方数据