CN204389487U - A kind of Fibre Optical Sensor laying apparatus for similarity simulation experiment - Google Patents

Abstract

The utility model discloses an optical fiber sensor laying device used for similar simulation experiments. The cavity of the similar physical model test bench of the device is filled with similar materials, and a vertical borehole is drilled in the similar material, and a laying pipe is inserted into the vertical borehole, and an optical fiber fixing groove is opened on the laying pipe, and the two ends of the optical fiber fixing groove A strain gauge is connected to the inside, and the strain gauge is connected to the strain gauge and the fiber holder respectively. The fiber holder is connected to the fiber hole, the rubber groove and the sensing fiber through fastening screws as a whole, and the upper end of the laying pipe is connected to a level gauge. Determine the vertical laying of the optical fiber by a level; determine that there is a certain coupling and friction between the laying sleeve and the optical fiber; the upper and lower ends of the optical fiber are respectively fixed and prestressed by the end clamping device. The structure is simple, the installation is convenient, and it is widely used in the field of vertical laying of sensing optical fibers in similar materials experiments in mining engineering or other structures.

Description

A fiber optic sensor laying device for similar simulation experiments

technical field

The utility model relates to the field of physical model experiments of similar materials in mining engineering, in particular to an optical fiber sensor laying device for monitoring model stress and strain for similar simulation experiments.

Background technique

Distributed optical fiber sensors are currently a research hotspot at home and abroad. The span of the optical fiber used for testing can reach tens of kilometers, with high resolution and small error. To obtain the entire temperature information, stress information, and strain information with a certain span range, using traditional single-point mobile or quasi-distributed sensing methods composed of multiple single points is time-consuming, costly and difficult in wiring. Its cost performance is very low. At this time, using fully distributed sensing is obviously the most effective method. This requires that the medium not only have high sensitivity, but also effectively transmit the induced signal. Optical fiber has such dual characteristics, and it also has the advantages of anti-electromagnetic interference, flame-proof, explosion-proof, extremely small size, and little influence on the measured temperature field, etc. other media cannot match.

Due to the superiority of the distributed optical fiber sensor, it can be applied to monitor the influence of coal mining and roadway excavation on the surrounding rock and the deformation of the overlying rock strata. In order to verify its feasibility, it is necessary to use similar physical simulation research methods authenticating.

Practice has proved that distributed optical fiber sensors can be used to monitor the disturbance of surrounding rock by mining. However, the corresponding relationship between the frequency shift change of the backscattered wavelength of the light band on the optical fiber and the displacement change of the rock formation has yet to be determined. Since the embedding process of the optical fiber will directly affect the determination process of this relationship, how to solve the problem of embedding the sensing optical fiber in the model has become the primary problem restricting the application of the optical fiber sensing technology in the deformation monitoring of similar physical model tests in mines.

Contents of the invention

The purpose of this utility model is to provide a simple structure, convenient installation, and effectively solve the damage and error caused by improper laying of optical fibers in the model test, thereby greatly improving the survival rate of sensing optical fibers and making the measured experimental data more accurate. A fiber optic sensor laying device for similar simulation experiments.

In order to overcome the deficiencies of the existing optical fiber laying methods, the technical solution of the utility model is solved in this way: a kind of optical fiber sensor laying device used for similar simulation experiments is composed of sensing optical fiber, optical fiber holder, strain gauge, laying pipe, optical fiber fixing Groove, level meter, stress meter and similar physical model test bench; the special feature of the utility model is that the cavity of the similar physical model test bench is filled with similar materials, and vertical boreholes are drilled in the similar material, and the vertical boreholes The laying pipe is inserted into the laying pipe, and an optical fiber fixing groove is opened on the laying pipe. Stress gauges are connected to both ends of the fiber fixing groove, and the stress gauges are respectively connected to the stress gauge and the optical fiber holder. The fastening screw is connected with the optical fiber hole, the rubber groove and the sensing optical fiber as a whole, and the upper end surface of the laying pipe is connected with a level gauge.

Compared with the prior art, the utility model has the following advantages:

The structure is simple, the installation is convenient, and it can effectively solve the damage and error caused by improper fiber laying in the model test, thereby greatly improving the survival rate of the sensing fiber and making the measured experimental data more accurate. Features:

1. The utility model has the feature of ensuring that the sensing optical fiber is laid in a straight line in the plane-like physical simulation model; thereby minimizing the influence of the laying process on the measurement.

2. The pre-tightening force can be applied to the optical fiber in advance and the pre-tightening force on the optical fiber can be maintained.

3. At the same time, using this device can more realistically simulate the process of drilling and embedding optical fibers in actual engineering, so that the overall situation of the experiment is closer to the actual engineering situation to the greatest extent.

4. Ensure that the sensing optical fiber is laid vertically inside the similar simulation model, so as to minimize the influence of the laying process on the measurement.

5. It is widely used in the physical model experiment of similar materials in mining engineering or the vertical laying field of sensing optical fibers inside other structures.

Description of drawings

Fig. 1 is a schematic diagram of the main view structure of the utility model;

Fig. 2 is the front structural schematic diagram of laying pipe;

Fig. 3 is a top view structural schematic diagram of Fig. 2;

Fig. 4 is the structural representation of stress gauge;

5 is a schematic structural view of an end fiber holder;

FIG. 6 is a schematic diagram of the specific implementation method in FIG. 1 .

1-sensing optical fiber; 2-end optical fiber holder; 3-strain gauge; 4-laying pipe; 5-fiber fixing groove; 6-level; 7-fiber hole; -fastening screws; 11-plane similar physical model test bench; 12-similar materials.

Detailed ways

Accompanying drawing is embodiment of the utility model.

Below in conjunction with accompanying drawing, content of the invention will be further described:

Example 1

A kind of optical fiber sensor laying device that is used for similar simulation experiment, this device is made up of sensing optical fiber, optical fiber fixer, stress gauge, laying pipe, optical fiber fixing groove, level instrument, strain gauge and similar physical model test bench; The cavity of the model test bench 11 is filled with similar materials 12, and a vertical borehole is drilled in the similar material 12, and a laying pipe 4 is inserted into the vertical borehole, and an optical fiber fixing groove 5 is opened on the laying pipe 4, and the optical fiber is fixed Both ends of the groove 5 are connected with strain gauges 3, and the strain gauges 3 are respectively connected with the strain gauge 8 and the optical fiber holder 2, and the optical fiber holder 2 is connected with the optical fiber hole 7, the rubber groove 9 and the sensor through fastening screws 10. The optical fiber 1 is connected as a whole, and a level 6 is connected to the upper end surface of the laying pipe 4 .

Example 2

After the similar model pavement is completed, drill a hole on the surface of the model, and the diameter of the drill hole is equivalent to the diameter of the optical fiber laying pipe. Put the sensing optical fiber for measurement into the fixing groove of the optical fiber laying pipe to fix it to ensure that the optical fiber is in a straight state. Put the optical fiber laying pipe down to the bottom along the drill hole, and fix the tail of the optical fiber through the bottom of the model with an optical fiber holder. The upper end of the fiber passes through the fiber hole of the strain gauge and the fiber holder respectively. After applying prestress to the fiber, the fiber is clamped through the rubber groove of the fiber holder and the fastening screw, and the prestress size is read by the strain gauge. To ensure that the optical fiber is laid vertically, it can be calibrated through the level gauge on the upper end of the optical fiber laying device. After confirming that the optical fiber is laid vertically, fill the laying pipe with similar materials, and gradually lift and remove the redundant laying pipes, so that the similar materials fall to the bottom of the hole, and compact them sequentially until the laying pipes are completely lifted to the outside of the model, and the drilled holes are filled with similar materials. Refilling, fiber laying is complete.

To sum up, the optical fiber laying pipe has an optical fiber fixing groove on the surface of the laying pipe. The optical fiber fixing groove is used to fix the optical fiber sensor and keep the optical fiber in a straight state. One of the end fiber holders is used to fix the optical fiber, and the other is used to maintain the prestress applied to the optical fiber. The spirit level is used to ensure that the optical fiber laying sleeve enters the borehole vertically.

Claims (1)

1., for a Fibre Optical Sensor laying apparatus for similarity simulation experiment, this device is made up of sensor fibre, fibre-optical fixator, taseometer, laying pipe, optical fiber fixing groove, level meter, stress sheet and scaled physical model testing table, it is characterized in that described scaled physical model testing table (11) lumen loading has analog material (12), vertical drilling is drilled with in analog material (12), insert in its vertical drilling and lay pipe (4), described laying pipe (4) has optical fiber fixing groove (5), described optical fiber fixing groove (5) both ends are connected with taseometer (3), described taseometer (3) is connected with stress sheet (8) and fibre-optical fixator (2) respectively, described fibre-optical fixator (2) is by holding screw (10) and optic fibre hole (7), rubber groove (9) is connected for overall with sensor fibre (1), described laying pipe (4) upper surface connects a level meter (6).