Abstract: Grasping the stress and deformation regularity of side pile is very important for the safety of pile-tunnel approach-based station. Based on the modified load-structure model, the deformation regularity of the side pile is studied and compared with the field-measured result. The result shows that the lateral displacement of the side pile from the top to the bottom plate will exhibit parabolic form and its lateral displacement below the bottom plate will basically be zero, and the initial branch system of the guide tunnel will be able to withstand the stress of largeportion of its surrounding rock. However, the lateral pressure coefficient near the bottom of the guide tunnel should be enlarged by 20 percent if the surrounding rock stress of the guide tunnel was ignored in the calculation model; and the lateral displacement of the side pile calculated with conventional load-structure model will be relatively small as a whole. The lateral displacement of the side pile calculated with modified load-structure model will be in better agreement with the field measured data. The axial force on side pile calculated with modified load-structure model will be greatly reduced and the shearing force in side pile and bending moment on it will bebasically unchanged.

Key words: pile-tunnel method, load-structure model, deformation regularity of side pile