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Mechanical behavior of sealed waterproof for shield tunnel segment joint under different assembling ellipticity
Zhang Junwei1, Guo Sicen1, Chen Yunyao2
1School of Geoscience and Technology, Southwest Petroleum University, Sichuan, Chengdu, China.
Science Progress
|January 25, 2021
Summary
Segment assembly ellipticity and joint angles are key to shield tunnel joint leakage. This study found a linear relationship between segment opening angle and ellipticity, impacting gasket performance.
Area of Science:
- Geotechnical Engineering
- Tunneling Engineering
- Waterproofing Technology
Background:
- Joint leakage in shield tunnels is a significant issue during construction and assembly.
- Ellipticity of segment assembly and segment joint angles are identified as primary causes.
- Chengdu Metro shield tunnel construction serves as the practical background for this research.
Purpose of the Study:
- To investigate the geometric relationship between segment assembly ellipticity and segment opening angle.
- To analyze the waterproof performance of gaskets under varying segment joint angles using numerical methods.
- To provide insights for improving shield tunnel gasket design, production, and quality control.
Main Methods:
- Geometric calculations were employed to establish the relationship between ellipticity and opening angle.
- Finite element analysis (FEA) was utilized to simulate and assess gasket performance under different joint angles.
- Nonlinear numerical analyses were conducted to interpret the results.
Main Results:
- A direct linear correlation was identified between the opening angle of segments and the degree of ellipticity.
- The study revealed that different side joint opening angles have varying impacts on gasket waterproofing.
- External joint opening angles were found to have a greater effect on waterproofing than internal angles.
Conclusions:
- The findings offer valuable references for the future design, manufacturing, processing, and quality inspection of shield tunnel gaskets.
- Understanding the relationship between assembly geometry and gasket performance is crucial for preventing tunnel joint leakage.
- This research contributes to enhancing the reliability and durability of shield tunnel structures.
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