| Combination with Dayangtian tunnel project which lies in landslide on the Naxi to Xu yong railway, tunnel construction deformation at landslide site and engineering measures are discussed by several methods such as investigation and research of data, theory analysis and FLAC numerical analysis method.Based on the geology of Dayangtian slide, Sweden method of slices and numerical analysis method are used to calculate slide safety factor. There is a conclusion:the slide is stable in the front of tunnel excavation, tunnel excavation won't induce slide.The first collapse of tunnel are analyzed by numerical analysis method:adjoining rock force state is very unfavorable; surface settlement is obvious that takes on the form of funnel. It is accord with the fact.The second collapse of tunnel are analyzed by numerical analysis method:after the pipe roof reinforcement, adjoining rock force state is still very unfavorable; surface settlement is still obvious that takes on the form of funnel. It is accord with the fact.The measures to control the collapse of tunnel are analyzed by numerical analysis method:after adopting the pipe roof reinforcement and fabrication of secondary lining on the tunnel, adjoining rock force state is improved greatly; surface displacement is very small The tunnel didn't occurs collapse and tunnel is stability. There is a conclusion:it is effective to adopt pipe roof reinforcement and fabrication of secondary lining on the tunnel at landslide site.Based on these studies, the measures to control Dayangtian tunnel construction deformation are put forward. These results are helpful to the resemble tunnel engineering in future. |
