Horizontal Tunnel Drainage Pipe Layout Without Lining Damage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tunnel drainage methods in water-rich strata face limitations in decompression and drainage efficiency, particularly in long tunnels, and can damage the secondary lining structure, while methods for horizontal directional drilling are inadequate for built tunnels.
Innovation Solution
A tunnel drainage method using ultra-long distance horizontal directional drilling to lay a horizontal perforated corrugated pipe, which directs underground water into side ditches without damaging the secondary lining, ensuring efficient decompression and drainage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If water diversion holes are made in the surrounding rock to discharge underground water, then drainage efficiency is improved, but the secondary lining structure is damaged
Solution Approach 1:
The drainage system is segmented into multiple components: drainage pipes with perforations, connection pipes, and collection channels. The drainage function is divided among these segments, allowing water to be collected through perforations in the drainage pipes without requiring holes through the secondary lining, thus maintaining structural integrity while achieving drainage efficiency
Solution Approach 2:
Drainage pipes are introduced as intermediary elements between the surrounding rock and the tunnel interior. These pipes with perforations allow water to pass from the surrounding rock into the drainage system without directly penetrating the secondary lining, serving as a mediator that protects the lining while enabling drainage
2Ease of manufacture
If drainage is carried out mainly in the annular direction at deformation joints, then construction is simplified, but decompression and drainage effect is limited in long tunnels
Solution Approach 1:
The drainage system transitions from purely annular drainage at deformation joints to a three-dimensional drainage network. Drainage pipes are arranged in multiple rows (first row, second row, third row) at different heights and positions, creating longitudinal and radial drainage paths that work together with the annular drainage, thereby enhancing drainage effectiveness in long tunnels while maintaining construction feasibility
Solution Approach 2:
The drainage pipes serve multiple functions: they collect water from the surrounding rock through perforations, transport water longitudinally along the tunnel, and connect to annular drainage systems at deformation joints. This multi-functionality allows a single drainage pipe system to address both longitudinal and annular drainage needs, improving overall effectiveness without significantly complicating construction
3Productivity
If horizontal directional drilling is used for long distance tunnel drainage, then drainage capability is improved, but the method cannot solve drainage problems in built tunnels
Solution Approach 1:
The drainage pipes are installed during the initial construction phase of the tunnel, before the tunnel enters service. The pipes are laid in the surrounding rock and connected to the tunnel drainage system during the construction process, ensuring that the drainage infrastructure is in place before the tunnel begins operation, thereby making the tunnel adaptable to drainage needs from the outset
Data Source
AI summary
The present disclosure provides a tunnel drainage method. The method includes: for an established existing tunnel, laying a drainage pipe by ultra-long distance horizontal directional drilling in the surrounding rock of the tunnel, wherein the drainage pipe is a horizontal perforated corrugated pipe, and underground water in the surrounding rock of the tunnel is depressurized and discharged through the drainage pipe. The present disclosure uses the ultra-long distance horizontal directional drilling to lay the drainage pipe, which can effectively decompress and discharge the underground water behind a secondary lining.