| The tunnel liner of unbonded circular anchored tendons had been used in modernhydroelectric engineering. It has a lot of advantages over traditional tunnel linermethods such as simpler in installation, more uniform in distribution of the prestress,more economical of the cost and etc. But the experience of using three dimensionsfinite element analysis (3D FEA) method to analyze a tunnel liner is seldom.In coordination with the XiLongChi Project in ShanXi province, this thesis willanalyze the stress distribution of the tunnel liner in details with 3D FEA method. Themain contents are listed as below:(1) The method of how to apply the tensioning force in the tendons in the calculationmodel. The tendons effect is took as the outer loads transferred to the liner model,and the load distribution coefficient is introduced to study the characteristic of theuniform cable prestress. The calculation methods with simple finite element modeland decreased number of the finite element make it easy to the consideration oftendons effect than before.(2) Establishing methods of the FEA model. Several factors are discussed, which is animprovement on the similar analyzing model used ever before. A new method isalso provided to establish the tunnel liner FEM or the parallel structure model.(3) The skills for analyzing the calculation results. Except for the regular calculationitems, two appending conditions were considered in the thesis, one is theoptimizing on the tensioning procedure, another is assuming the break-off of atendon.(4) A new structure with one row of boxouts was proposed and analyzed.
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