Abstract：
Based on a river-crossing tunnel project, actual measurements were taken regarding the staggered seg? ment, joint and water leakage as shield construction passed the flood control wall, river bed and underground pipelines, and the relationship among all these factors was analyzed considering the tunnel axis offset and segment ovality. The results show that: the external environment changes are the main controlling factors for water leakage in the tunnel, and it is recommended that the design for waterproofing the shield tunnel should be conducted by segments based on the external environment; a positive correlation exists between the shield posture, variation of the segment ring′s ovality and the tunnel′s stagger, joint and leakage; external water leakage is mainly leakage of the circumferential joint, and water leakage at the key segment is more serious than at other segments and especially concentrated at the corner of the segment. Corresponding countermeasure are proposed.
2018, Vol. 55 