| In recent years,many highway double-arch tunnels have been built . the route of double-arch is fluent and impropriating the area is small and the ratio of utilizing space is high.It is easy to connect the out road with avoiding the embankment in the tunnel exit or the bridge framing.It has the advantages of adapting the condition and protecting the environment and engineering quantitatively.but The double multi-arch tunnel is designed under the condition buried shallow tunnel with the moderate to short length. The surrounding rocks will happen when the load is removed and returned and the stress will be redistributed duringtunnel digging.The surrounding rock will lose the stability when its strength is too low to adapt the stress redistribution. So it is an important content with closely relating to the construction of tunnel and operation in the high way that analyzing the stability of surrounding rock..Based on the Qianjiashan double-arc tuunel and shangpo double-arc tuunel, using the finite element method and large-scale commercial finite element software-ADINA,first taking the qianjiashang tunnel as the object of study, we simulate the common excavating methods of double-arc tunnel respectively, analyze the stress and strain of wall rock and support structure of each method, and recommend the best excavating method to construct double-arc tunnel in wall rocks of III. According to this conclusion,taking the tunnel as the object of study,we simulation the "three headings method" constructon of the tunnel and analyze the "three headings method" in detail. And then , we also carry also out plane elastoplastic simulation of double-arc tunnel, and get the development regularity of plastic region. Finally we set up three-dimensional space model to simulate the space effect during tunnel construction,analyze the transaction between the left tunnel and the right tunnel.The conclusions we draw can also play a directive role in highway double-arc tunnel construction. |
PDF Full Text Request