Experimental Study on the Improvement of Gasket Gas Tightness at Segment
Joints in Shield Tunnels
(1. China Railway Siyuan Survey and Design Group Co., Ltd., Wuhan 430063; 2. Jiangyin Haida Rubber and Plastic Co., Ltd.,Wuxi 214424; 3. China Railway 14th Bureau Group Co., Ltd., Jinan 250014; 4. Jiangsu Provincial Transportation Engineering Construction Bureau, Nanjing 210004; 5. Nanjing Public Works Construction Center, Nanjing 210001;6. Northwest Rubber & Plastics Research & Design Institute Co., Ltd., Xianyang 712000)
Abstract：
The gasket contact surface gas leakage model has been built based on the Roth model, in order to investi?
gate the correlation between the segment gasket surface roughness and segment joint gas tightness in shield tunnels.The surface roughness of forming die for elastic gasket of segment is improved by nitriding, laser strengthening and ultrasonic polishing, so as to improve the surface quality of the formed gasket, and the result is demonstrated through testing. The study indicates: the gas leak rate can be used as an indicator for assessing the gas tightness of gasket; the coefficient of friction of polished gasket is 7%~9% less than that of unpolished gasket, while decrease of coefficient of friction will effectively reduce the deformation of gasket during assembly. The gas tightness of the gasket formed by polished die is 10% better than that of the gasket formed by unpolished die.
XIAO Mingqing1 ZHONG Yuanyuan2 CHEN Peng3 WANG Jun4 QI Zhaochen5 ZHANG Weibin6
.Experimental Study on the Improvement of Gasket Gas Tightness at Segment
Joints in Shield Tunnels[J] MODERN TUNNELLING TECHNOLOGY, 2023,V60(6): 262-268
2023, Vol. 60 