Model Tests And Numerical Study On The Destructions Of Overlaying Soil And Tunnels By Faulting

Soil will be destructed during faulting movements.The destruction areas often appear like bands and generate a few rupture bands finally.Meanwhile,fissures and steeps also are formed at the rupture outcropping points.The buildings under and on ground will be damaged seriously due to rupture bands propagation.Hence,It is an important task in seismic resistance research to study the law of fault rupture propagation,the sites of outcropping points and the influence area of fault rupture.Since the past studies are based on horizontal fields,the study about faulting under inclined fields has not been reported yet.Compared with horizontal fields,inclined fields are more common.Whether the study results from horizontal filed are applicable for the faulting under inclined fields is worth considering.At first,the faulting model test device is designed and the nonlocal PIV wild-vector-removing technique is proposed based on the nonlocal theory.Compared with some conventional wild-vector-removing methods,the nonlocal method can remove wild vectors more effectively and reduce PIV errors considerably.the nonlocal wild-vector removing method is applied in the faulting experiment on horizontal field and shows good adaptability.Lastly,the influence of reverse faulting on different inclined angles is studied by faulting model test device and PIV technique,which contributes to discover basic law of faulting on inclined fields.Based on the augmented finite element method proposed by Ling etc.and the discontinuous patch test designed by Dolbow etc.,the precision and stability of the Hansbo&Hansbo’s type of methods is studied.The reason why the Hansbo&Hansbo’s type of methods cannot pass the discontinuous patch is studied.And the influence of refining integrating subdomains on the results of discontinuous patch test is also studied.At last,an analytical integration method to resolve stiffness matrix is derived.The reason why the conventional nonlocal model is not applicable when the finite elements are large is indicated.Assuming the distribution of inner variables,element average effect is eliminated and an improved nonlocal model,which doesn’t degenerate into local model when elements are large,is obtained.Then the analytical solutions of conventional nonlocal model and improved nonlocal model for one-dimension tension bar problem are derived.Meanwhile,the improved nonlocal model for two-dimension problem is also proposed and the effectiveness of the improved nonlocal model is verified by a two-dimension uniaxial tension example.Utilizing Finite element software ABAQUS and combining analytical integration method with improved nonlocal model,the interaction between faulting under inclined field and tunnel underground is studied.The study emphasis is put on the influence of tunnel sites,tunnel shapes and tunnel-tunnel interaction and some results are achieved.