Abstract:
In order to provide reference and technical support for the design and construction of the tunnel across anticline core area, special test was conducted at the section of K8+559-K8+527 of the Zhougongshan tunnel. The testing results show that the contact pressure at crown is larger than that of haunch and side wall at the test sections;a contrastive analysis on the results of test sections and verification sections was carried out and it was found the contact pressure deceases somewhat, which means the scheme of“support after release”and increasing reserved deformation is effective and reasonable; tunnel deformation is governed by the geological condition, unreasonable construction method and combination of various adverse factors are the inducing factors; the process of deformation and failure can be generalized as excavation—unloading—differential resilient deformation—layer separation—bending failure of the top roof as simply supported beam. The research results provide calculation parameters for theoretical analysis and also basic data for the following study, accumulating the experience for the design and construction of super-long tunnel in complex stress condition.