Abstract:Research purposes: The diversion tunnel in Baishuijiang three-level power station has a 42 m high maximum water head , underpassing the Shoupayan tunnel of the existing Neijiang-Kunming Railway, and is only 13.06 m apart from foundation base of the tunnel sidewall. In the construction process of the diversion tunnel it is easy to cause the railway tunnel settlement and the lining destruction. In order to guarantee the operation safety of existing tunnel,the rational construction methods and lining patterns should be adopted necessarily.
Research methods: 3D-σ is adopted for analyzing the influence of derivation tunnel on the railway tunnel. The theoretical analysis and internal force of lining which are calculated out by the ANSYS procedure are adopted to analyze the influence of blasting vibration.
Research results: The load combination controlling lining pattern is determined and the crack under the normal use is controlled.
Research conclusions:(1)For design of compression seepage tunnel underpass railway,the analysis should be made for the influenced area of railway tunnel by the construction of seepage tunnel , the composition should be made rationally for load,the verification should be made for the limitation status of load-bearing capacity with the basic composition and for the limitation status of crack with the standard composition.(2)The verification of crack is the control condition for calculation of distributed steel to seepage tunnel.(3)Steel fibre sprayed concrete should be used for support in construction because the pressure of internal water is the main control load due to less deformation and displacement of wall rock around railway tunnel caused by excavation of seepage tunnel.