Research on Waterproof Performance of Composite Sealing Gasket for Assembly Joints of Prefabricated Subway Stations

The prefabricated subway stations are easily affected by hydrological, geological, and other factors, and there is a great risk of water leakage. Taking a station of Changchun subway as the background, the paper explores the stress and waterproof performance of composite sealing gaskets at the assembly joints of prefabricated components are explored. Taking the average contact stress of the sealing gasket as the waterproof index, the compression test and numerical simulation of the composite sealing gasket were carried out. The secondary waterproof effect of the composite sealing gasket and the influence of different offsets on the waterproof performance were analyzed. Through comparative analysis, the accuracy of the numerical model is verified. Under the secondary waterproof effect, the waterproof performance of the composite sealing gasket is significantly improved, and water seepage mainly occurs on the contact surface between the sealing gaskets. It is recommended that the joint opening and offset be controlled within 7 mm and 5 mm, respectively, which can fully meet the long-term waterproof requirements of prefabricated subway stations.