Based on the 1# shield tunnel of SU ZHOU rail transit, a 3D discontinuous contact computational model of shield tunnel segment and bending bolts is built. This paper study about the stress and the deformation of shield tunnel segment with actual loads ,and the influences on shield tunnel segment by properly install the bolts. Result shows that timely apply pre-stress on the bolts could effectively decrease the deformations on segment joint by the shear resistance capacity of the bolts. The maximum deformation reduces from 3.580mm to 0.302mm. And there appear an open-angle which turn to outside or inside on segment joint. The maximum spacing of the open-angle is 0.66mm, and the maximum angle is 0.108 degree. In most position about shield tunnel segment, installed bolts reduced the axial forces and increased or reduced the bending moments.