Shield launching construction method suitable for narrow space
By installing portal steel rings and splicing extension steel rings at the starting end of the shield tunnel shaft, the problem of insufficient starting space for the shield machine in a confined space was solved, achieving a sealing effect and ensuring construction safety and efficiency.
Patent Information
- Application Number
- CN202610107470.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-27
- Publication Date
- 2026-02-27
AI Technical Summary
In confined spaces, the effective extension length of the steel ring at the tunnel entrance is limited, resulting in insufficient space for the tunnel boring machine to launch and making it impossible to seal. This leads to the risk of mud and water leakage and soil loss, affecting construction safety and efficiency.
A portal steel ring is installed at the starting end of the shield tunnel, and an extension steel ring is spliced to it. Sealing components are installed, and a demolition platform is erected. The underground continuous wall at the starting end is demolished layer by layer from top to bottom to ensure sealing and safe construction.
By extending the steel ring and splicing it with the portal steel ring, the insufficient effective length in the narrow space was compensated for, the shield machine was sealed, mud and water leakage and soil loss were avoided, and the shield machine launch was guaranteed to proceed smoothly.
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Figure CN121576087A_ABST
Abstract
Citation Information
Patent Citations
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