Research About The Effect Of Weak Intercalation To Tunnel Surrounding Rock

ABSTRACT:It has been proved by a large number of underground engineering that the weak interbed often has decisive effect of the stability of surrounding rock mass. Based on analyzing and collecting predecessors' materials, in this paper, a systemic summary on the research status concerning this issue and the engineering characteristic of week interbed and basic theories of surrounding rock stress have been given. The idea of use practice to practice is adopted in this paper. Firstly, by the FLAC3D, a numerical analysis software, which is based on finite difference, using the elastic-plastic constitutive law and Mohor-Coulomb failure criterion, the model trial done by predecessor have been modeled and analysis by the software of FLAC3D, besides, the result is also compared with the result of model trial in the thesis. Secondly, systematic numerical test have been carried out to study the satiability of tunnel surrounding rock with the change of thickness of the week intercalation, the change of obliquity of the week interbed, the change of the distribution of the week interbed, the change of the distance between the interbed and the limit of excavation, the change of depth of burial. What's more, the influence of the interbed to the stability of the tunnel surrounding rock in different also have been limited in this paper. Finally, the collapse range of the Tianhengshan tunnel of the highway round the city of Haerbin, furthermore, the reason of collapse have been analysis.plentiful result have been drawn via numerical test, which have important reference value about stability analysis of underground engineering surrounding rock containing week interbed.