Study On The Technology And Excavation Adaptability Of The Cantilever Tunneling Machine For Milling Tunneling

The geological conditions of Tongxiang Shanzhuang tunnel section of Dalian Binhai Avenue are complex,with weak surrounding rock,well-developed joints,and building complexes on the surface.The disturbance control requirements for construction are very high.Therefore,this section of the project requires the use of a cantilever-type roadheader for excavation.The method of milling and tunneling by a cantilever tunneling machine has little disturbance to the surrounding rock,the construction is relatively safe,and the milling and excavation surfaces are smooth and flat,which is conducive to construction support.However,the use of cantilever-type roadheader milling and excavation method also has the problems of low adaptability of surrounding rock strength,unreasonable process flow,and imperfect supporting process,which makes it difficult to exploit the advantages of cantilever-type roadheader.In order to understand the adaptability of the tunnel excavation method by the cantilever tunneling machine,this article combines the actual project of Tongxiangshanzhuang tunnel section of Binhai Avenue in Dalian,China to control the construction of the tunnel to disturb the surrounding rock as the starting point,taking into account the construction efficiency and project cost,and the limited use.The differential geotechnical calculation software FLAC3D simulates and analyzes the five steps of the whole section construction of the tunnel and the other three types of construction methods to study the deformation laws of the surrounding rock with different construction methods and step sequences.The main research work and the results achieved are as follows:(1)At the domestic and foreign research on the construction technology of soft wall rock tunneling technology and milling and excavation construction technology,the factors influencing the adaptability of the milling and excavating tunnel construction of the cantilever tunneling machine are discussed,and the applicable to the milling method of the cantilever tunneling machine is proposed.Rock classification method.(2)The FLAC3D is used to simulate and simulate the tunnel construction.The gradient load release method is used to simulate the construction process of the cantilever roadheader,and the disturbance of the non synchronous sequence path to the surrounding rock is analyzed and compared,and the best step path is the horizontal cycle step path.(3)Combining the milling and excavating step path with the construction method,and comparing and analyzing the surrounding rock disturbance responses of different construction methods,the best method of excavation is the cross-in-between wall method,and an auxiliary process system and machine suitable for the construction of the cantilever tunneling machine are proposed.Supporting.(4)Compared with the traditional drilling method from the angle of engineering technology.,engineering efficiency and engineering economy,According to the analysis results,the economic tunnel length of the cantilever roadheader milling method is obtained.