摘要
Abstract
Reinforcement of soft ground is a very common measure to ensure the stability of the foundation in pit engineering,while the effect of pit reinforcement on the existing undercrossing tunnels is rarely studied at present.In order to investigate the effect of pit reinforcement on the vertical deformation of the existing undercrossing tunnel,three typical forms of pit bottom reinforcement,namely,full-top reinforcement,skirt reinforcement,and drawbar reinforcement,were selected to reinforce the bottom of the pit at different heights.The test results show that:these three forms of reinforcement have good effect on the suppression of tunnel bulging deformation,and the full-tang reinforcement has the best effect;when the reinforcement height exceeds a certain value,the suppression effect of pit bottom reinforcement on the tunnel bulging de-formation will be changed to the promotion of the tunnel settlement deformation;the support piles construction has the greatest effect on the de-formation of the tunnel in the process of pit construction,and at the same time,it is the largest deformation of the tunnel in the process of pit construction,and it should pay special attention to the support piles construction during the construction of pit.Special attention should be paid to the supporting pile construction stage during the pit construction;The vertical deformation of the undercropping tunnel is mainly affected by the deformation of the pit floor uplift.关键词
基坑加固/下卧隧道/竖向变形Key words
Pit reinforcement/Undercrossing tunnel/Vertical deformation分类
交通运输
