Abstract:

Waterproofing is very important in the construction and operation of shield tunneling. The waterproof performance of traditional gaskets is easy to fail at the joint of concrete segments. The embedded sealing gasket is precast with concrete segments, which is different from the traditional one. Hence, the waterproof performance of a new embedded sealing gasket is studied. And the waterproof performance of embedded sealing gasket in tunnel segment joint is analyzed and discussed based on model test and FEM numerical simulation. The results shows that the embedded sealing gasket with the crosssection type adopted under the opening of 7 mm and staggered joint of 10 mm can meet the water pressure requirement of 0.6 MPa for Shanghai Deep Drainage and Storage Tunnel, which solves the waterproof failure at the joint of concrete segments by traditional gasket. In addition, by setting grooves on both sides of the sealing strip, the contact stress between the foot of the sealing gasket and the concrete can be effectively reduced, the degree of local stress concentration can be also reduced, the integrity of the concrete segment can be ensured, and the waterproof performance of the joint can be improved.

Key words: shield tunnel, segment joint, embedded sealing gasket, waterproof performance, model test, numerical simulation