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Effectiveness analysis of a novel rectangular tunnel boring machine with planetary transmission for box jacking
Peng Ma1,2, Yahong Zhao3,4,5, Hideki Shimada2
1School of civil engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
Scientific Reports
|November 7, 2024
Summary
A novel planetary transmission mechanism enhances full-face excavation boring machines, improving tunneling efficiency and soil mixing for large-section box jacking projects. This technology offers a reliable solution for challenging underground construction.
Area of Science:
- Geotechnical Engineering
- Mechanical Engineering
- Tunneling Technology
Background:
- Traditional rectangular tunnel boring machines (TBMs) exhibit limitations in tunneling efficiency and soil mixing.
- These limitations impede the progress of long-distance, large-section box jacking projects.
Purpose of the Study:
- To introduce a new full-face excavation boring machine utilizing a planetary transmission mechanism.
- To demonstrate its effectiveness in overcoming the drawbacks of traditional TBMs for box jacking.
Main Methods:
- Development of a novel boring machine based on a planetary transmission mechanism with eccentric cutter heads.
- Case study analysis of an underground highway passage construction project in Japan.
- Evaluation of excavation face support, cutter-head layout, obstacle removal, and jacking resistance reduction strategies.
Main Results:
- The planetary mechanism enables full-face excavation through the synchronized rotation of eccentric cutter heads.
- Monitoring data confirmed the machine's applicability, reliability, and engineering performance.
- Superior performance in ground settlement control and tunneling speed was observed.
Conclusions:
- The planetary transmission mechanism-based boring machine presents a significant advancement for rectangular shield machines.
- It offers a comprehensive solution to the challenges in large-section box jacking projects.
- The technology demonstrates enhanced tunneling efficiency and reduced environmental impact.
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