Distribution type optical fibre measuring method and system for deep deformation of soil

Abstract

The invention is a fixed measuring method and system for earth deep distortion, the measuring system is made up of slant pipe, distributed fiber sensing channel, data collecting device, computer control model, and data processing model. It uses distributed fiber sensing technology based on self Brillouin dispersion theory, the sensing fibers are pasted on the external surface of the slant pipe, and then the slant pipe is embedded in the earth for measuring the distortion and shift of earth. When the deep earth moves, the earth drives the slant measuring pipe to generate distortion, the strain capacity of the external wall of the slant measuring pipe is changed, then uses BOTDR to measure the strain distribution of the fiber on the external wall of the slant measuring pipe directly, the collection process of data can be realized by computer control model, the data is induced into the data processing model by the computer control model, and the distortion quantity can be worked out according to a certain arithmetic, thus the distortion or shift of earth can be acquired.

Description

1. Technical field [0001] The invention belongs to the technical field of geotechnical engineering monitoring, and relates to a method and a measurement system for monitoring deep deformation of rock and soil bodies based on distributed optical fiber sensing technology. 2. Background technology [0002] At present, there are many methods for monitoring deformation of deep rock and soil. By laying inclinometers and using inclinometers to measure deformation of rock and soil, it is a common method for monitoring deformation of rock and soil engineering such as foundation pits and slopes. When the rock-soil mass moves, the inclinometer pipe buried in the rock-soil mass moves synchronously with the soil mass, and the displacement of the inclinometer pipe is the displacement of the rock-soil mass. Then, by inserting the inclinometer probe into the inclinometer pipe along the guide groove in the pipe, slowly sliding down, and measuring the inclination angle between the inclinomete...

AI Technical Summary

Problems solved by technology

[0003] When the deformation of the rock and soil intensifies and the curvature of the test conduit becomes larger, the mobile inclinometer cannot pass through the conduit and the monitoring is interrupted, which cannot meet the test requirements for large local deformation of the middle and late drilling

The mobile inclinometer requires the inner cavity of the inclinometer to be as smooth and regular as possible, and the sticky sediment will cause the reading error of the inclinometer

In addition, when the catheter is twisted or the catheter joint is not correct, the guide wheel will deviate from the guide groove or even jump to another set of guide grooves. At this time, the recorded data is very unreliable

Although the accuracy of the mobile inclinometer probe is high, the above reasons will reduce the reliability of the mobile inclinometer

Images