Abstract Segment watertightness is crucial in shield tunneling. In East Asia, most shield tunnels use single-layer segment linings, which makes the reliability of elastic gaskets more critical because of the lack of an inner lining. Based on the Nanjing Weisan Road River Crossing Tunnel, a new watertightness test system was designed for use under high water pressure and automatic triaxial loading. With a full-scale elastic gasket and concrete specimens, many tests were carried out with respect to the assembly force of the elastic gasket and the watertightness of I-shaped and T-shaped joints. Finally, the optimized section of an EPDM elastic sealing gasket was obtained in terms of high performance and appropriate structure. The test results show that the gasket assembly force is closely related to the watertightness, and the hardness of the gasket and grove fill rate have a direct impact on its performance.
Abstract:
Segment watertightness is crucial in shield tunneling. In East Asia, most shield tunnels use single-layer segment linings, which makes the reliability of elastic gaskets more critical because of the lack of an inner lining. Based on the Nanjing Weisan Road River Crossing Tunnel, a new watertightness test system was designed for use under high water pressure and automatic triaxial loading. With a full-scale elastic gasket and concrete specimens, many tests were carried out with respect to the assembly force of the elastic gasket and the watertightness of I-shaped and T-shaped joints. Finally, the optimized section of an EPDM elastic sealing gasket was obtained in terms of high performance and appropriate structure. The test results show that the gasket assembly force is closely related to the watertightness, and the hardness of the gasket and grove fill rate have a direct impact on its performance.
.Experimental Study on the Reliability of Shield Tunnel Segment Joints
to Remain Watertight Under High Water Pressure[J] MODERN TUNNELLING TECHNOLOGY, 2013,V50(3): 87-93