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Published on: September 19, 2018
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Layout optimization for non-equidistant thrust system of tunneling machine based on geometric progression under mixed
Kongshu Deng1, Lu Zeng1, Yicheng Ding1
1Engineering Research Center of Advanced Mining Equipment, Ministry of Education, Hunan University of Science and Technology, Xiangtan, China.
Science Progress
|December 13, 2019
Summary
A novel geometric progression method optimizes non-equidistant thrust systems for tunnel boring machines in complex geology. This approach improves force transmission, preventing segment damage during curved tunneling operations.
Area of Science:
- Geotechnical Engineering
- Tunneling Technology
- Mechanical Systems Design
Background:
- Complex geological structures and tunneling conditions (curved paths, varying rock/soil strength) pose challenges for uniform thrust systems.
- Uniform thrust systems can lead to unbalanced loads, causing cracks and dislocations in tunnel segments.
- Existing systems are not optimized for the dynamic forces encountered in composite foundations.
Purpose of the Study:
- To develop a geometric progression method for designing non-uniform thrust systems for tunnel boring machines.
- To address the limitations of uniform thrust systems in complex geological and tunneling scenarios.
- To enhance the force transmission performance and stability of tunneling operations.
Main Methods:
- Proposal of a geometric progression increasing difference model based on force transmission laws.
- Detailed analysis of the characteristics of the proposed non-uniform thrust system design method.
- Application of the model to a 9.49 m diameter tunnel boring machine with 14 pairs of jacks.
Main Results:
- Successful application of the optimized non-equidistant thrust system in curved tunnel construction in Germany.
- Demonstrated improved force transmission performance compared to the original system, quantified by the coefficient of variation.
- Validation of the geometric progression method for designing efficient thrust systems.
Conclusions:
- The geometric progression method provides a theoretical basis for designing non-equidistant thrust systems.
- Optimized non-uniform thrust systems enhance force transmission and structural integrity in tunneling.
- This approach is crucial for improving the safety and efficiency of tunnel boring in challenging geological conditions.
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