Research purposes: As the lining of the metro shield tunnel is commonly assembled of the jointed segmental precast concretes,during the operation of the subway,the longitudinal uneven settlements will happen due to various factors,resulting in enlarging the joint opening of the adjacent segments to cause water leaking between adjacent segments. It is necessary to analyze and research the mechanism of the water leakage of the shield tunnel.
Research conclusions: The longitudinal uneven settlement of the tunnel will make opening of the circumferential seam and weaken the property of the water resistance of the elastic gasket,resulting in water leaking between segments. The long coefficient influenced by the circumferential joints produces little impact on circumferential seam while the stiffness ratio of the different circumferential width and different bolts with the concrete will produce a certain impact on the opening of the circumferential seam. The big stiffness ratio of the circumferential width and bolts with the concrete is not good for the waterproofing of the joint segments. This research can provide the reference to the waterproofing design and maintenance of the tunnel.