Technical Study On Mechanical Behaviour Of The Surrounding Rock, Monitoring And Measurement For Construction Of Twin Tunnels With Small Spacing

Due to complicated topographical and geological conditions as well as large numbers of mountainous areas, constructions of high-grade highway unavoidably meet with lots of tunnel works. As a result of special geological and topographical limitations, space of tunnels cannot satisfy with general technical codes. Therefore, such special structure shape as small spacing tunnel, twin-bore tunnel should be applied.First, the paper discuss technical on controlling measure for construction of tunnels, analyses applied features on construction of twin tunnels with small spacing and need project of controlling measure.Second, the paper applied 2D and 3D FEM numerical analysis to study application on construction of twin tunnels with small spacing, such key technologies as controlling and matter need attention.1,Gating through studies on the stability of surrounding rocks in twin tunnels with small spacing and no support by 2D FEM, draw the conclusion of what are the main factors effecting on stress distribution of surrounding rocks and deformation characters.2,Gating through numerical simulated calculation with excavation of twin tunnels with small spacing and existential support by 2D and 3D FEM, draw the conclusion of what are the main factors effecting on stress distribution of surrounding rocks and deformation characters, in the condition of different on the rank of surrounding rocks or depth of embedment.3,Gating through numerical simulated calculation with different method of excavation of twin tunnels with small spacing and existential support by 2D FEM, draw the conclusion of what are the main factors effecting on stress distribution of surrounding rocks and deformation characters in the condition of the different method of excavation. Last, gating through the analysised conclusion of numerical calculation, and the date of controlling measure on two small spacing tunnels——gaolongkou tunnel and lingshang tunnel of huangshan quzhou nanping high speed highway ,generalize points and major position on controlling measure for construction of twin tunnels with small spacing.