Abstract：Based on the model of structure and surrounding rock mass co-deformation，the reasonable optimum supporting structure parameters are determined for Yuanliangshan railway tunnel. Through stability analysis of bearing capacity of grouted region around the tunnel，the minimum size of reinforced region is proposed to be 3 m. On the basis of elasto-plastic FEM calculation for 38 cases，the relationship curves can be obtained of the size of grouting reinforced region versus the thickness of secondary lining with the secondary lining safety factor 2.4. In addition，the results demonstrate that the higher level grouting can be used to reduce the supporting structure parameters.
