Study On The Causes Of Lining Failure And The Treatment Scheme For The Kunlunqiao Railway Tunnel

Many lining failures happened to the study objective of this thesis, Kunlunqiao Tunnel of Qingzang Railway after it was built, such as lining breach, leakage, alkali infiltration, inanity behind the lining. Work was done in this thesis, including field investigation, file consolidation of engineering geologic surveying, design, construction and so on, statistic analysis for the detailed mileage of lining failure and defection and comprehensive analysis about the mechanical behavior, tunnel design, monitoring and treatment scheme. After the analysis, this thesis jumps to conclusion that the main causes of lining crack are bias and over great rock pressure, the insufficient and uneven lining thickness and the inanity behind lining. The reason for alkali infiltration is that alkalescency salt deposits on the surface of the lining after water from the cracks and condensation carried them out. During the study, the assumption for linking-rod method was used to help analyze internal forces inside the lining material of three specified cross sections, using the large finite element software, ANSYS to prove our former analysis to the failure causing. This thesis also presents the special treatment for different types of lining failure, obtaining some results and some practical engineering conclusions, which is meaningful to some other comparable engineering.