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Objective To prevent water leakage issues in large-diameter shield tunnel, ensure high-speed train operational safety and normal tunnel functionality, it is necessary to carry out analysis and research on tunnel segment joint deformation and waterproof performance under high-speed train vibration. Method Relying on the Zhanjiang Bay Subsea Tunnel project, a soil-tunnel three-dimensional model and a sealing gasket-groove two-dimensional refined model are established using finite element software. First, the dynamics response and deformation characteristics of segment joints under high-speed train vibration in large-diameter shield tunnel are studied, with longitudinal joints as example. Then, the waterproof performance of a sealing gasket is analyzed based on the most adverse joint deformation working condition. Result & Conclusion The research results indicate that under the vibration of a single high-speed train, the displacement response process of segment joints can be divided into three stages: deformation increase, deformation being danger, and deformation decline. During the second stage, significant joint opening and misalignment occur at the upper part and both ends of the segment ring, while adjacent joints experience reduced opening and misalignment due to compression from both adjacent side segments. There is almost no deformation at the joints below the track bed, as the tunnel track bed significantly mitigates the impact of train vibration on segment linings. The contact stress between sealing gaskets follows a U-shaped distribution, decreasing from the central contact area towards both edges between the sealing gasket and the segment groove. Leakage is more likely to occur at the contact surfaces between the sealing gaskets than along the contact path between the sealing gasket and the segment groove. Under the most adverse working condition of this project, a provided triangular perforated sealing gasket is found to meet the tunnel waterproof requirements.

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High-speed train (HST) vibrations in the dense residential and industrialized areas founded particularly on soft soil deposits, may lead to discomfort in daily human life, decrease the serviceability life of the structural elements and malfunctioning of the sensitive electronic equipment used in industrial production. In this paper, in-situ measurements were carried out in the free field conditions to examine the effects of ground vibrations caused by HSTs on the surrounding residential lands. Due to both variation in geological and topographical characteristics and railroad track-support properties, the section between "Gebze-Pamukova" has been considered as the target test area of the Istanbul-Ankara HST line in North-Western Turkey. This in-situ experimental study provides comprehensive measurement data that structural engineers and city planners can evaluate in the feasibility phase of the project when planning residential and industrial facilities in new settlements nearby railroads. • Site-specific ground vibrations were measured on Istanbul-Ankara high-speed railway. • In-situ investigations at the grade, embankment and culvert sections were performed. • The subsoil stiffness and stabilization of the route modifies vibration generation. • A resonance case is observed at the train passing on the elevated rail embankment. • Track earthworks affect the transmission of ground vibration to the environment. [ABSTRACT FROM AUTHOR]