Excavation Frame Offset Control for Secant Diaphragm Wall Continuity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Deep ground boring and excavating processes face challenges in maintaining the verticality and continuity of diaphragm walls due to ground irregularities, leading to potential discontinuities and increased resource consumption when thickening the walls to compensate.
Innovation Solution
A method that involves periodically determining and correcting the offset between the excavation frame and the first screen during the second boring step to ensure continuous overlap, using sensors and path correction means like hydraulic skids to maintain a minimum overlap thickness, thereby ensuring the secant nature of the screens over the entire length.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the thickness of the screen is increased to ensure continuity, then the reliability of the wall is improved, but the use of resources and manufacturing cost increase significantly
Solution Approach 1:
The system uses sensors (electrodes, detectors, or wave sources) to continuously measure the offset between the frame and the first screen during the second boring step, providing real-time feedback that enables dynamic position correction to maintain continuity without increasing screen thickness
Solution Approach 2:
The patent replaces the traditional mechanical approach of ensuring continuity by over-dimensioning screen thickness with a sensor-based measurement and active correction system that uses electromagnetic or acoustic fields to detect and correct position deviations
2Manufacturing precision
If the screen thickness is increased to compensate for ground irregularities, then the manufacturing precision of the continuous wall is improved, but the device complexity and cost increase
Solution Approach 1:
Real-time measurement of frame offset from the first screen using sensors enables continuous feedback control, allowing the system to maintain manufacturing precision through active correction rather than over-engineering the screen structure
Solution Approach 2:
The patent introduces sensors and correction means as intermediary elements between the frame and the ground, enabling precise control of the boring process without requiring increased screen thickness or complex structural solutions
3Manufacturing precision
If active position correction is implemented during the second boring step, then the manufacturing precision of the wall is improved, but the device complexity increases due to addition of sensors and correction means
Solution Approach 1:
The system implements feedback control by measuring the offset between the frame and the first screen using sensors and actively correcting the frame position based on these measurements, achieving precise overlap control
Solution Approach 2:
The correction system uses the already-made first screen as a reference guide for the second boring step, allowing the system to self-correct its position based on the actual ground conditions rather than relying on pre-planned trajectories
Data Source
AI summary
The invention relates to an installation (10) for making a continuous wall in ground (S), the installation comprising:an excavation machine (14) having a frame (16) with a bottom end (16b);determination means (80) for periodically determining the offset between the frame and a first screen while making a second screen in the ground juxtaposed with the first screen; andcorrection means (50) for periodically correcting the position of the frame (16) so as to reduce the offset as determined by the determination means between the frame (16) and the first screen (E1), and maintain overlap between the longitudinal side of the frame and the longitudinal side of the first screen in such a manner that the second screen is secant with the first screen (E1) over the entire length of the shorter of the first and second screens, thereby forming the wall that is continuous.