Soil body transverse deformation optical fiber implantation device with quick connector and monitoring method

Abstract

The invention relates to a soil transverse deformation optical fiber implantation device with a quick connector and a monitoring method, the device comprises an attachment circular tube, a sensing optical fiber and an optical fiber quick connector, the attachment circular tube is formed by connecting a plurality of standardized hollow circular tubes end to end, the sensing optical fiber is fixed in a notch groove of the standardized hollow circular tube, and the optical fiber quick connector is connected with the attachment circular tube. The two ends of each sensing optical fiber penetrate into the hollow round holes in the two ends of the notch groove and extend outwards, the two ends of each sensing optical fiber are connected with optical fiber quick connectors, and each optical fiber quick connector is communicated with the sensing optical fiber; the method comprises the following steps of engineering investigation, standardized hollow circular pipe manufacturing, sensing optical fiber laying, drilling, pipe burying, backfilling, communication measuring and space positioning. According to the invention, the problems of construction difficulty caused by traction of the attached pipe by the sensing optical fiber and depth mileage positioning difficulty caused by lack of positioning marks in the existing attached sensing optical fiber implantation technology are solved, the construction is simple, convenient and modularized, the implantation is efficient, and temperature compensation can be realized.

Description

Technical Field

[0001] This invention relates to the field of soil deformation monitoring technology, and in particular to a fiber optic implantation device and monitoring method for lateral soil deformation with a quick connector. Background Technology

[0002] The foundations of building structures are typically embedded in soil, making soil deformation monitoring a crucial focus in the engineering field. This monitoring allows for early warning of risks originating from underground, thus preventing disasters. Currently, commonly used soil deformation monitoring technologies are based on inclinometers, which measure the angle of inclinometer tube tilt deformation using a probe to deduce the degree of soil deformation. Although various types of inclinometers have been developed, shortcomings remain: sliding / guide wheel inclinometers require manual monitoring; fixed inclinometers require separate cables for each section of the inclinometer tube, making installation difficult and limiting monitoring depth; array displacement gauges require customization, are non-disassembly, and difficult to transport; segmental displacement gauge probes are susceptible to environmental vibrations and electromagnetic interference, resulting in insufficient monitoring performance. Furthermore, the sampling resolution of existing inclinometers is typically 0.5–1 m, leading to significant errors in integration results.

[0003] To overcome the shortcomings of inclinometer monitoring technology, the engineering community is gradually promoting soil deformation monitoring technology based on fiber optic sensing. This technology boasts excellent performance characteristics such as high testing accuracy (reaching micro-strain level), high sampling frequency (interval less than 0.1m), strong anti-interference ability, waterproofing, moisture resistance, and corrosion resistance. However, the sensing fiber is relatively soft, and direct burial in the soil can lead to core breakage during large deformations. Furthermore, it can only monitor longitudinal strain and cannot deduce the specific horizontal deformation direction of the soil. Therefore, attaching the sensing fiber to a pipe remains the mainstream monitoring method. However, in actual construction, ensuring the continuity of the sensing fiber requires all fiber-attached pipes to be pulled by the sensing fibers of adjacent pipes, posing significant challenges to construction. In addition, the lack of positioning markers at the measuring points attached to the pipes makes depth positioning difficult.

[0004] To address the aforementioned issues, this invention discloses a soil lateral deformation fiber optic implantation device and method with a quick connector. This device enables simple and modular implantation of soil lateral deformation sensing fibers, and the quick connector can also serve as a positioning marker for spatial positioning of the measuring point's depth and mileage. Furthermore, this implantation technology allows for temperature compensation, resulting in more accurate monitoring results in response to strain magnitude. Summary of the Invention

[0005] The purpose of this invention is to provide a soil lateral deformation fiber optic implantation device and monitoring method with a quick connector, so as to solve the construction difficulties caused by the traction of the attachment tube by the sensing fiber of the adjacent attachment tube and the difficulty of depth and mileage spatial positioning caused by the lack of positioning markers in the existing attached sensing fiber optic implantation technology. Furthermore, the invention is simple and modular in construction, highly efficient in implantation, and can achieve temperature compensation.

[0006] The technical solution of this invention:

[0007] A soil transverse deformation fiber optic implantation device with a quick connector includes a drilled hole in the soil, an attachment tube installed in the drilled hole, the attachment tube being composed of multiple standardized hollow tubes connected end to end, the standardized hollow tubes being divided into a bottom tube, an upper tube, and a top tube; the upper end of the top tube has a first circular hole for the insertion of a sensing fiber; the outer surface of the standardized hollow tube has four longitudinal straight grooves for limiting the sensing fiber; both the upper and lower ends of the longitudinal straight grooves have second circular holes for the insertion of the sensing fiber.

[0008] Each standardized hollow tube is equipped with a sensing optical fiber, and both ends of the sensing optical fiber are connected to quick connectors.

[0009] Furthermore, the length of the bottom circular tube is L. 底管 The bottom end is a closed arc head, and the top end is a double-ended copper connector with external threads; the length of the upper connecting round pipe is L. 接管 The bottom end is the internal threaded end of a double-ended copper connector, and the top end is the external threaded end of a double-ended copper connector; the length of the top circular tube is L. 顶管 The bottom end is the internal thread end of the copper double-ended swivel joint, and the top end is a closed flat head. The first round hole is opened on the closed flat head. The bottom round tube, the upper round tube and the top round tube are connected by tightening the copper double-ended swivel joint.

[0010] Furthermore, the angle between any two adjacent longitudinal straight grooves and the center of the circle is 90°; the four longitudinal straight grooves of all standardized hollow tubes are aligned on the same straight line after connection, and the length of a single longitudinal straight groove is L. 刻槽 Each standardized hollow tube has a slot at the top for fixing a quick connector.

[0011] Furthermore, the sensing optical fiber is fixedly bonded to the longitudinal straight groove of the standardized hollow tube using glass glue, and both ends are inserted into the standardized hollow tube through the second round hole of the longitudinal straight groove and extend outward to both ends of the standardized hollow tube.

[0012] One end of the quick connector is connected to the sensing fiber, and the other end is connected to a quick connector from another sensing fiber, for connecting two different sensing fibers.

[0013] Furthermore, the upper end of the sensing fiber on the top circular tube passes through the first circular hole; the quick connector at the upper end of one of the sensing fibers is connected to the quick connector at the upper end of the adjacent sensing fiber; the quick connectors at the upper ends of the remaining two sensing fibers are connected to the fiber demodulation instrument.

[0014] The quick connector at the lower end of the sensing fiber on the bottom circular tube is connected to the quick connector at the lower end of the symmetrical sensing fiber.

[0015] Furthermore, the extension L of the sensing fiber in the second circular hole under the longitudinal straight groove of the bottom circular tube is... 底下 It should be no less than the spatial resolution L of the fiber optic demodulator. 空间分辨率 The extension L of the sensing fiber in the second circular hole on the longitudinal straight groove of the bottom circular tube. 底上 It should be no less than the spatial resolution L of the fiber optic demodulator. 空间分辨率 ;

[0016] The extension L of the sensing fiber optic cable is obtained by the longitudinal straight groove of the upper circular tube and the second circular hole below it. 接下 It should be equal to the distance L from the second circular hole to the second circular hole on the longitudinal straight groove of the adjacent standardized hollow circular tube below. 两孔 The extension L of the sensing fiber on the second circular hole in the longitudinal straight groove of the bottom tube 底上 The sum of these values, and the extension L of the sensing fiber optic cable through the second circular hole on the longitudinal straight groove of the upper circular tube. 接上 It should be equal to the outer extension L of the sensing fiber in the second circular hole on the longitudinal straight groove of the bottom circular tube. 底上 ;

[0017] The extension L of the sensing fiber under the second circular hole in the longitudinal straight groove of the top circular tube. 顶下 It should be equal to the distance L from the second circular hole to the second circular hole on the longitudinal straight groove of the adjacent standardized hollow circular tube below. 两孔 The extension L of the sensing fiber on the second circular hole in the longitudinal straight groove of the bottom circular tube 底上 The sum of the two sensing optical fibers in the second circular hole on the longitudinal straight groove of the top circular tube includes two adjacent fibers with an outer extension L. 顶上-1 Not less than the distance L from the borehole point to the fiber optic demodulation instrument 解调 The longer sensing fiber, and the two remaining outer extension L 顶上-2 The extension L of the sensing fiber on the second circular hole in the longitudinal straight groove of the bottom circular tube is equal to the extension L of the sensing fiber. 底上 Shorter sensing optical fibers.

[0018] Let N be the number of upper circular pipes required for monitoring the borehole. 接管 N 接管 If ≥0, then the required material quantity and length of the implantation device are:

[0019] The number of standardized hollow round tubes is N 接管 +2;

[0020] The total length of the attached circular tube is L 底管 +N 接管 L 接管 +L 顶管 ;

[0021] The total length of the sensing fiber is 4L. 底下 +4L 底上 +4N 接管 L 接下 +4N 接管 L 接上 +4L 顶下 +2L 顶上-1 +2L 顶上-2 This value is not less than (14+8N) 接管 )L 空间分辨率 +(4+4N 接管 )L 两孔 +2L 解调 .

[0022] A method for monitoring transverse soil deformation using fiber optic cable implantation with quick connectors, employing the aforementioned fiber optic cable implantation device with quick connectors, includes the following steps:

[0023] Step S01, Engineering Survey: Based on the actual engineering situation requiring monitoring of lateral soil deformation, determine the depth and diameter of the boreholes and the quantity and size of the standardized hollow tubes.

[0024] Step S02, Standardized Hollow Round Tube Manufacturing: Produce standardized hollow round tubes according to the design quantity and dimensions;

[0025] Step S03, Sensor Fiber Deployment: Fix the sensor fiber onto the groove of the standardized hollow tube, and pass both ends of the sensor fiber through the second circular holes at both ends of the groove and extend them outwards. Then connect multiple quick connectors to the extended sections of each sensor fiber. For the bottom tube, the quick connectors of the extended sensor fibers through the second circular holes below the groove need to be pre-connected in a cross shape. For the top tube, the two extended sections with an extension length of L through the second circular holes above the groove need to be pre-connected. 顶上-2 The shorter sensing fiber is connected and placed in the slot of the fixed fiber quick connector.

[0026] Step S04, Drilling: Use a drilling rig to drill vertically from the ground surface into the soil at the designed location to form a borehole, and then clean the borehole.

[0027] Step S05, Pipe embedding: Vertically insert a bottom round tube, several upper round tubes, and a top round tube into the borehole in sequence. When the lower adjacent standardized hollow round tube is embedded to a specified depth, connect the sensor fiber quick connector extending from the lower end of the next standardized hollow round tube to be embedded with the sensor fiber quick connector extending from the upper end of the lower adjacent standardized hollow round tube, and place it in the slot of the fixed fiber quick connector. Then tighten the copper buckle double-ended quick connector to achieve a tight connection between the two adjacent standardized hollow round tubes, so that the four grooves of the adjacent standardized hollow round tubes are on the same straight line after connection. Repeat this step until the top round tube is implanted and the bottom round tube is implanted to the bottom of the borehole.

[0028] Step S06, Backfilling: Pull the two longer epitaxial sensing optical fibers from the second circular hole on the top circular tube groove out of the soil, cover them with closed flat ends, backfill with original soil sand or bentonite balls, and inject water to compact.

[0029] Step S07, Continuity Test: Use an optical power meter to test the connectivity of the two longer epitaxial sensing optical fibers from the second circular hole on the top circular tube groove. After confirming the connectivity, connect them to the optical fiber demodulation instrument to complete the implantation of the soil lateral deformation sensing optical fiber.

[0030] Step S08, Spatial Positioning: Because the stress state of the optical fiber inside the quick connector is different from that of the sensing optical fiber in the grooved section, the peak frequencies of the optical signals generated by the two are different. This allows for the rapid positioning of the optical fiber quick connector at the optical signal mileage. Based on the mileage distance of each measuring point of the sensing optical fiber relative to the quick connector, and combined with the actual device design, the optical signal mileage position of each measuring point of the sensing optical fiber is rapidly correlated with the spatial position, thus achieving spatial positioning.

[0031] Furthermore, the soil lateral deformation sensing fiber optic implantation device performs temperature compensation and interpolates the peak frequency offset values ​​of the optical signals from each epitaxial sensing fiber in the depth direction to obtain the temperature-affected peak frequency offset value depth variation function Δν. 温度 (z), thus the peak frequency offset Δν of the sensing fiber optic signal in the grooved section, which is simultaneously affected by temperature and deformation at the same depth, is compared with that of the optical signal in the sensing fiber optic signal in the grooved section. 温度,变形 (z) Subtract the values ​​to obtain the final peak frequency offset Δν of the sensing fiber optic signal in the grooved section, which is only affected by deformation. 变形 (z), the formula is: Δν 变形 (z)=Δν 温度,变形 (z)-Δν 温度 (z).

[0032] The beneficial effects of this invention are:

[0033] (1) The standardized hollow circular tube sensing optical fibers of the present invention are independent of each other, which can realize simple modular construction and solve the construction difficulties caused by the traction of the sensing optical fibers on the adjacent attached tube in the existing attached sensing optical fiber implantation technology.

[0034] (2) The quick connector contained in this invention can serve as a positioning device, thereby enabling a quick correspondence between the optical signal mileage position and the spatial position of each measuring point of the sensing fiber, solving the problem of depth mileage spatial positioning difficulties caused by the lack of positioning markers in the existing attached sensing fiber implantation technology.

[0035] (3) The present invention achieves temperature compensation by subtracting the peak frequency offset of the optical signal at the sensing fiber measuring point of the standardized hollow circular tube grooved section at the same depth from the peak frequency offset of the optical signal of the sensing fiber in the epitaxial free section.

[0036] This invention is reasonably designed and can be applied to monitoring the lateral deformation of soil. It enables simple modular construction, spatial positioning, and temperature compensation, making it efficient to implant, accurate to monitor, and easy to promote. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the sensing fiber implantation device of the present invention.

[0038] Figure 2 This is a schematic diagram of the top circular tube structure of the present invention.

[0039] Figure 3 This is a schematic diagram of the upper circular tube structure of the present invention.

[0040] Figure 4 This is a schematic diagram of the bottom circular tube structure of the present invention.

[0041] Figure 5 This is a partial schematic diagram of the connection between adjacent standardized hollow circular tubes.

[0042] Figure 6 This is a schematic diagram of the cross-section of the circular tube of the present invention.

[0043] Figure 7 This is a Brillouin light signal energy test diagram.

[0044] Figure 8 This is a flowchart of the sensing fiber implantation method of the present invention.

[0045] In the diagram: 1—bottom round tube, 2—upper round tube, 3—top round tube, 4—sensing fiber, 5—quick connector, 6—fiber optic demodulation instrument, 7—backfill soil, 8—closed arc head, 9—external thread end of copper double-ended connector, 10—internal thread end of copper double-ended connector, 11—closed flat head, 12—slot, 13—straight groove, 14—second round hole. Detailed Implementation

[0046] The invention will now be further described with reference to the accompanying drawings.

[0047] like Figures 1-8 As shown, the present invention provides a soil transverse deformation optical fiber implantation device with a quick connector, including a drilled hole in the soil, an attachment tube disposed in the drilled hole, the attachment tube being composed of multiple standardized hollow tubes connected end to end, the standardized hollow tubes being divided into a bottom tube 1, an upper tube 2, and a top tube 3; the upper end of the top tube 3 is provided with a first circular hole for the sensing optical fiber 4 to pass through; the outer surface of the standardized hollow tube is provided with four longitudinal straight grooves 13 for limiting the sensing optical fiber 4; the upper and lower ends of the longitudinal straight grooves are provided with second circular holes 14 for the sensing optical fiber 4 to pass through.

[0048] Each standardized hollow tube is equipped with a sensing optical fiber 4, and both ends of the sensing optical fiber 4 are connected to quick connectors 5.

[0049] The length of the bottom circular tube 1 is L 底管 =2.2m, with a closed arc head 8 at the bottom and an external threaded end 9 of a double-ended copper connector at the top; the length of the upper connecting round pipe 2 is L. 接管 =2.2m, the bottom end is the internal thread end 10 of the copper double-ended union, and the top end is the external thread end 9 of the copper double-ended union; the length of the top round tube 3 is L. 顶管 =2.2m, the bottom end is the internal thread end 10 of the copper buckle double-ended union, the upper end is the closed flat head 11, and the first round hole is opened on the closed flat head 11; the bottom round tube 1, the upper round tube 2 and the top round tube 3 are connected by tightening through the copper buckle double-ended union.

[0050] The angle between any two adjacent longitudinal straight grooves and the center of the circle is 90°; the four longitudinal straight grooves of all standardized hollow tubes are aligned on the same straight line after connection, and the length of a single longitudinal straight groove is L. 刻槽 Each standardized hollow tube has a slot 12 at the top for fixing a quick connector 5.

[0051] The sensing optical fiber 4 is fixedly bonded to the longitudinal straight groove of the standardized hollow tube using glass glue, and its two ends are inserted into the standardized hollow tube through the second round hole 14 of the longitudinal straight groove and extend outward to both ends of the standardized hollow tube.

[0052] One end of the quick connector 5 is connected to the sensing fiber 4, and the other end is connected to the quick connector 5 from another sensing fiber 4, for connecting two different sensing fibers 4.

[0053] The upper end of the sensing fiber 4 on the top circular tube 3 passes through the first circular hole; the quick connector 5 at the upper end of one of the sensing fibers 4 is connected to the quick connector 5 at the upper end of the adjacent sensing fiber 4; the quick connectors 5 at the upper ends of the remaining two sensing fibers 4 are connected to the fiber demodulation instrument 6.

[0054] The lower end quick connector 5 of the sensing optical fiber 4 on the bottom circular tube 1 is connected to the lower end quick connector 5 of the symmetrical sensing optical fiber 4.

[0055] In one embodiment of the present invention, the outer extension L of the sensing optical fiber 4 with a groove under the bottom circular tube 1 is [not specified]. 底下 Equal to the spatial resolution L of the fiber optic demodulation instrument 空间分辨率 =0.5m, the outer extension L of the sensing fiber optic cable 4 with a groove on the bottom circular tube 1 is etched. 底上 Equal to the spatial resolution L of the fiber optic demodulation instrument 空间分辨率 =0.5m;

[0056] Upper circular tube 2 grooved lower circular hole sensing fiber 4 outer extension L 接下 Equal to the distance L from the circular hole to the circular hole on the adjacent standardized hollow tube groove below. 两孔 =0.2m and the outer extension L of the sensing fiber 4 with the groove on the bottom circular tube 1 is 0.2m. 底上 The sum of the lengths, the upper circular tube 2 groove, the upper circular hole, the sensing fiber optic 4, the outer extension L 接上 The outer extension L of the sensing fiber optic cable with the groove on the bottom circular tube 1 is equal to that of the circular hole on the bottom circular tube 4. 底上 ;

[0057] Top circular tube 3 grooves, lower circular hole, sensing fiber optic 4, outer extension L 顶下 It should be equal to the distance L from the circular hole to the circular hole on the adjacent standard hollow tube groove. 两孔 =0.2m and the outer extension L of the sensing fiber 4 with the groove on the bottom circular tube 1 is 0.2m. 底上 The sum of the two outer extensions L of the sensing optical fiber 4 with the groove on the top circular tube 3 includes two adjacent outer extensions L. 顶上-1 Equal to the distance L from the drilling point to the fiber optic demodulation instrument 解调 =3m longer sensing fiber 4, and 2 remaining external extensions L 顶上-2 The outer extension L of the sensing fiber optic cable with the groove on the bottom circular tube 1 is equal to that of the circular hole on the bottom circular tube 4. 底上 4. Shorter sensing fiber.

[0058] In one embodiment of the present invention, as a preferred embodiment, the borehole is formed by drilling vertically from the ground surface into the soil using a drilling rig. The borehole diameter is 130mm, which is larger than the outer diameter of the copper double-ended joint 910 (90mm). The borehole depth is determined to be 12m based on engineering survey data and the required number of standardized hollow tubes, with a margin of 1.0m on the basis of a length of not less than 5 times the length of the standardized hollow tubes.

[0059] The fiber optic demodulation instrument 6 is selected as a BOTDA demodulation instrument, and its length, along with the longer of the two circular holes from the groove on the top circular tube 3, is L. 顶上-1 The epitaxial sensing fiber 4 is connected via a quick connector 5 and is used to analyze the monitoring data of the sensing fiber 4.

[0060] The spatial resolution refers to the ability of the fiber optic demodulation instrument 6 to resolve spatial markers of strain distribution, with a size of 0.5m.

[0061] In one embodiment of the present invention, the number of upper circular pipes required for monitoring the borehole is N. 接管 =3, the required material quantity and length of the implantation device are:

[0062] The number of standardized hollow round tubes is N 接管 +2 = 5;

[0063] The total length of the attached circular tube is L 底管 +N 接管 L 接管 +L 顶管 =11m;

[0064] The total length of the sensing fiber is 4L. 底下 +4L 底上 +4N 接管 L 接下 +4N 接管 L 接上 +4L 顶下 +2L 顶上-1 +2L 顶上-2 This value equals (14 + 8N) 接管 )L 空间分辨率 +(4+4N 接管 )L 两孔 +2L 解调 =28.2m;

[0065] The number of quick connectors is 8 (N) 接管 +2) = 40.

[0066] In one embodiment of the present invention, the optical fiber quick connector 5 adopts an ST-type snap-fit ​​connection, and its components are: ferrule, connector body, optical fiber, and connection device.

[0067] like Figure 5 The method for implanting optical fiber for lateral deformation sensing in soil with a quick connector, as shown, includes the following steps:

[0068] Step S01, Engineering Survey: Based on the actual engineering situation of monitoring the lateral deformation of the soil, determine the required drilling depth of 9m, diameter of 130mm, and the number of standardized hollow round pipes of 5 with an outer diameter of 70mm.

[0069] Step S02, Standardized Hollow Round Tube Fabrication: According to the design quantity and size, produce standardized hollow round tubes, including bottom round tube 1, upper connecting round tube 2 and top round tube 3. According to the design specifications of the two ends of each type of standardized hollow round tube, install the corresponding copper buckle double-ended connectors 9, 10 and closed end 8, and open the fixed fiber groove and the second round hole 14 at both ends of the groove.

[0070] Step S03, Sensor Fiber Deployment: Use glue to fix the sensor fiber 4 onto the groove of the standardized hollow tube, and pass both ends of the sensor fiber 4 through the second circular holes 14 at both ends of the groove and extend them outwards. Then connect multiple quick connectors 5 to the extended sections of each sensor fiber 4. For the bottom tube 1, the quick connectors 5 of the extended sensor fiber 4 through the second circular holes 14 under the groove need to be pre-connected in a cross shape. For the top tube 3, the two extended sections of the sensor fiber 4 through the second circular holes 14 on the groove need to be extended by L. 顶上-2 The shorter sensing fiber 4 is mated with the quick connector 5 and placed in the slot of the fixed fiber quick connector.

[0071] Step S04, Drilling: Use a drilling rig to drill vertically from the ground surface into the soil at the designed location to form a borehole, and then clean the borehole.

[0072] Step S05, Pipe embedding: Vertically insert a bottom round tube 1, several upper round tubes 2, and a top round tube 3 into the borehole in sequence. When the lower adjacent standardized hollow round tube is embedded to a specified depth, connect the sensor fiber 4 quick connector 5 extending from the lower end of the next standardized hollow round tube to be embedded with the sensor fiber 4 quick connector 5 extending from the upper end of the lower adjacent standardized hollow round tube, and place it in the slot 12 of the fixed fiber quick connector 5. Then tighten the copper buckle double-ended live connectors 9 and 10 to achieve a tight connection between the two adjacent standardized hollow round tubes, so that the four grooves of the adjacent standardized hollow round tubes are on the same straight line after connection. Repeat this step until the top round tube 3 is implanted and the bottom round tube 1 is implanted to the bottom of the borehole.

[0073] Step S06, Backfilling: Place the longer of the two tubes from the second circular hole 14 on the top circular tube 3 (length L) into the backfill. 顶上-1 Extend the epitaxial sensing fiber 4 out of the soil, cover it with a closed flat head 11, backfill with original soil sand or bentonite balls, and then inject water and compact it.

[0074] Step S07, Continuity Test: Use an optical power meter to test the longer of the two wires (length L) from the second circular hole 14 on the top circular tube 3. 顶上-1 The connectivity of the epitaxial sensing fiber 4 is confirmed, and then connected to the fiber demodulation instrument 6 to complete the implantation of the soil lateral deformation sensing fiber.

[0075] Step S08: Spatial positioning.

[0076] The spatial positioning principle of the soil lateral deformation sensing fiber optic implantation device is as follows:

[0077] like Figure 7 The diagram shown is a Brillouin optical signal energy test diagram according to an embodiment of the present invention. The horizontal axis represents the fiber optic mileage, and the vertical axis represents the Brillouin scattered light frequency. The color represents the corresponding energy intensity. It can be clearly seen that the peak frequency of the optical signal at the two quick connectors 5 in the diagram is discontinuous and the scattered light frequency range is wider, thus forming a spike. Therefore, the position of the fiber optic quick connector 5 in the optical signal mileage can be quickly located. Based on the mileage distance of each measuring point of the sensing fiber 4 relative to the quick connector 5, and combined with the actual device design, the optical signal mileage position of each measuring point of the sensing fiber 4 can be quickly correlated with the spatial position, that is, spatial positioning can be achieved.

[0078] To achieve more accurate measurement of the peak frequency of the optical signal, this invention also performs temperature compensation before spatial positioning:

[0079] Because the peak frequency offset of the optical signal is affected by both temperature and deformation, and each standardized hollow tube with a grooved second circular hole 14 has an epitaxial sensing fiber 4 (such as...) Figure 7 The free segment of the optical fiber shown is not under stress and is in a free state, only affected by temperature. It deviates somewhat from the peak frequency offset of the optical signal in the loaded segment. Interpolation can be performed on the peak frequency offset of the optical signal in each epitaxial sensing fiber along the depth direction to obtain the depth variation function Δν of the temperature-affected peak frequency offset. 温度 (z), thus, compared with the grooved sensing fiber 4 (e.g., at the same depth, which is simultaneously affected by temperature and deformation) Figure 7 The peak frequency offset value Δν of the optical signal in the loaded section of the fiber is shown. 温度,变形 (z) Subtract the values ​​to obtain the final peak frequency offset Δν of the optical signal in the grooved section of the sensing fiber 4, which is only affected by deformation. 变形 (z), the formula is: Δν 变形 (z)=Δν 温度,变形 (z)-Δν 温度 (z).

[0080] In summary, this invention is reasonably designed and can be applied to monitoring the lateral deformation of soil, enabling simple modular construction, spatial positioning, and temperature compensation, resulting in efficient implantation, accurate monitoring, and easy promotion.

[0081] The above description is only a preferred embodiment of the present invention and should not be construed as a limitation of this application. All equivalent changes and modifications made in accordance with the scope of the patent application of the present invention should be covered by the present invention.

Claims

1. A soil transverse deformation fiber implantation device with a quick connector, characterized in that, The application relates to a soil transverse deformation optical fiber implantation device with a quick connector, which comprises a drill hole formed in a soil body, and an attached circular pipe arranged in the drill hole, wherein the attached circular pipe is formed by connecting a plurality of standardized hollow circular pipes end to end, the standardized hollow circular pipes are divided into bottom circular pipes, upper connecting circular pipes and top circular pipes, a first circular hole for passing a sensing optical fiber is formed in the upper end of the top circular pipe, four longitudinal linear grooves for limiting the sensing optical fiber are formed in the outer surface of the standardized hollow circular pipe, and second circular holes for passing the sensing optical fiber are formed in the upper and lower ends of the longitudinal linear grooves. A sensing optical fiber is arranged on each standardized hollow circular pipe, and the two ends of the sensing optical fiber are connected with quick connectors.

2. The soil transverse deformation fiber installation device with a quick connector according to claim 1, characterized in that, The bottom circular pipe has a length of L 底管 , a closed arc head at the bottom end, and a copper buckle double-end connector outer threaded end at the upper end; the upper connecting circular pipe has a length of L 接管 , a copper buckle double-end connector inner threaded end at the bottom end, and a copper buckle double-end connector outer threaded end at the upper end; the top circular pipe has a length of L 顶管 , a copper buckle double-end connector inner threaded end at the bottom end, and a closed flat head at the upper end; the first circular hole is arranged on the closed flat head; the bottom circular pipe, the upper connecting circular pipe and the top circular pipe are connected by screwing the copper buckle double-end connectors.

3. The soil transverse deformation fiber installation device with quick connector according to claim 1, characterized in that, The angle between two adjacent longitudinal straight grooves and the center of the circle is 90°; the four longitudinal straight grooves of all the standardized hollow circular tubes are respectively arranged on the same straight line after being connected, and the length of a single longitudinal straight groove is L 刻槽 Each of the top of the standardized hollow circular tubes is provided with a clamping groove for fixing a quick connector.

4. The soil transverse deformation fiber installation device with quick connector according to claim 1, characterized in that, The sensing optical fiber is fixedly bonded in the longitudinal linear groove of the standardized hollow circular pipe by using glass cement, the two ends of the sensing optical fiber are passed into the standardized hollow circular pipe from the second circular holes of the longitudinal linear groove, and the sensing optical fiber extends outwards from the two ends of the standardized hollow circular pipe. One end of the quick connector is connected with the sensing optical fiber, and the other end of the quick connector is connected with the quick connector of another sensing optical fiber, so as to connect two different sensing optical fibers.

5. The soil transverse deformation fiber installation device with quick connector according to claim 1, characterized in that, The upper end of the sensing optical fiber on the top circular pipe is passed out of the first circular hole, the quick connector of the upper end of one sensing optical fiber is connected with the quick connector of the upper end of the adjacent sensing optical fiber, and the quick connectors of the upper ends of the remaining two sensing optical fibers are connected on a fiber demodulation instrument. The lower end quick connector of the sensing optical fiber on the bottom circular pipe is connected with the lower end quick connector of the opposite sensing optical fiber.

6. The soil transverse deformation fiber installation device with quick connector of claim 1, wherein, Bottom circular tube longitudinal linear grooving lower second circular hole sensing fiber extension length L 底下 Should be no less than the spatial resolution of the fiber demodulation instrument L 空间分辨率 , Bottom circular tube longitudinal linear grooving upper second circular hole sensing fiber extension length L 底上 Should be no less than the spatial resolution of the fiber demodulation instrument L 空间分辨率 ; The length L of the extension of the sensing fiber above the second circular hole of the longitudinal linear grooving of the upper circular pipe shall be equal to the distance L from the second circular hole to the second circular hole of the longitudinal linear grooving of the lower adjacent standardized hollow circular pipe 接下 The length L of the extension of the sensing fiber above the second circular hole of the longitudinal linear grooving of the lower circular pipe shall be equal to the distance L from the second circular hole to the second circular hole of the longitudinal linear grooving of the upper adjacent standardized hollow circular pipe 两孔 The length L of the extension of the sensing fiber above the second circular hole of the longitudinal linear grooving of the bottom circular pipe shall be equal to the distance L from the second circular hole to the second circular hole of the longitudinal linear grooving of the upper adjacent standardized hollow circular pipe 底上 The length L of the extension of the sensing fiber above the second circular hole of the longitudinal linear grooving of the upper circular pipe shall be equal to the distance L from the second circular hole to the second circular hole of the longitudinal linear grooving of the upper adjacent standardized hollow circular pipe 接上 The length L of the extension of the sensing fiber above the second circular hole of the longitudinal linear grooving of the bottom circular pipe shall be equal to the distance L from the second circular hole to the second circular hole of the longitudinal linear grooving of the upper adjacent standardized hollow circular pipe 底上 ; The second circular hole on the top circular tube longitudinal linear grooving sensing fiber extension length L 顶下 Should be equal to the distance L from the second circular hole to the lower adjacent standardized hollow circular tube longitudinal linear grooving second circular hole 两孔 And the second circular hole on the bottom circular tube longitudinal linear grooving sensing fiber extension length L 底上 The sum of the second circular hole on the top circular tube longitudinal linear grooving sensing fiber includes 2 adjacent extension length L 顶上-1 Not less than the distance L from the drilling point to the optical fiber demodulation instrument 解调 The longer sensing fiber, and the remaining 2 extension length L 顶上-2 Equal to the second circular hole on the bottom circular tube longitudinal linear grooving sensing fiber extension length L 底上 The shorter sensing fiber. Let the number of upper coupling pipes required to monitor the borehole be N 接管 , N 接管 ≥ 0, then the amount and length of material required for the implant device are: Number of standardized hollow circular tubes N 接管 +2; The total length of the attachment circular tube is L 底管 + 接管 L 接管 + 顶管 ; the total length of sensing fiber is 4L 底下 +4L 底上 +4N 接管 L 接下 +4N 接管 L 接上 +4L 顶下 +2L 顶上-1 +2L 顶上-2 , which is not less than (14+8N 接管 )L 空间分辨率 +(4+4N 接管 )L 两孔 +2L 解调 .

7. A method of monitoring soil lateral deformation by optical fiber implantation with quick connector, characterized by, The soil transverse deformation optical fiber implantation device with the quick connector is used to perform the following steps. Step S01, engineering investigation: according to the engineering actual situation of needing to monitor the soil transverse deformation, the depth and diameter of the drill hole and the number and size of the standardized hollow circular pipes are determined. Step S02, standardized hollow circular pipe production: the standardized hollow circular pipes are produced according to the designed number and size. Step S03, sensing optical fiber layout: fix the sensing optical fiber on the notched groove of the standardized hollow circular tube, and pass the two ends of the sensing optical fiber through the second circular holes at the two ends of the notched groove and extend outward, then connect a plurality of quick connectors with the extended segments of each sensing optical fiber, and for the bottom circular tube, the quick connectors of the sensing optical fiber extending out of the second circular holes below the notched groove are pre-connected in a "cross" shape, and for the top circular tube, the two shorter sensing optical fibers extending out of the second circular holes above the notched groove with a length of L 顶上-2 are connected and placed in the clamping groove of the fixed optical fiber quick connector; Step S04, drilling: a drill is used to vertically drill into the soil body from the ground surface to form a drill hole at the designed position, and hole cleaning is completed. Step S05, pipe burying: a bottom circular pipe, a plurality of upper connecting circular pipes and a top circular pipe are sequentially vertically implanted into the drill hole, when the next to be implanted standardized hollow circular pipe is implanted to the specified depth, the quick connector of the sensing optical fiber extending outwards from the lower end of the next to be implanted standardized hollow circular pipe is connected with the quick connector of the sensing optical fiber extending outwards from the upper end of the next to be implanted standardized hollow circular pipe, and is placed in the clamping groove of the fixed optical fiber quick connector, then a copper buckle double-end joint is tightened to realize the close connection of the two adjacent standardized hollow circular pipes, so that the four grooves of the adjacent standardized hollow circular pipes are arranged on the same straight line after connection, and the step is repeatedly performed until the top circular pipe is implanted and the bottom circular pipe is implanted to the bottom of the drill hole. Step S06, backfilling: two sensing optical fibers extending outwards from the second circular holes of the grooves on the top circular pipe are pulled out of the soil body, a closed flat head is covered, and the original soil sand or bentonite ball is used for backfilling and water is poured for tamping. Step S07, test connectivity: use the optical power meter to test the connectivity of the two longer epitaxial sensing optical fibers from the second circular hole on the top of the circular groove, and after confirming the connectivity, connect with the optical fiber demodulation instrument to complete the implantation of the soil lateral deformation sensing optical fiber. Step S08, spatial positioning: due to the different stress states of the optical fiber in the quick connector and the sensing optical fiber in the groove section, the peak frequencies of the light signals generated by the two are different, which can quickly locate the position of the optical fiber quick connector in the light signal mileage, and thus according to the mileage distance of each measuring point of the sensing optical fiber relative to the quick connector and combined with the actual device design, the light signal mileage position and the spatial position of each measuring point of the sensing optical fiber are quickly corresponded, that is, spatial positioning is realized.

8. The soil cross-strain fiber implantation monitoring method with a quick connector according to claim 7, characterized in that, The soil transverse deformation sensing optical fiber implanting device carries out temperature compensation, and interpolates the peak frequency shift value of each epitaxial sensing optical fiber light signal in the depth direction to obtain a temperature influence peak frequency shift value depth change function Δν 温度 (z), thereby subtracting the peak frequency shift value Δν 温度,变形 (z) of the notched section sensing optical fiber simultaneously affected by temperature and deformation at the same depth, to obtain the final notched section sensing optical fiber light signal peak frequency shift value Δν 变形 (z) affected only by deformation, and the formula is: Δν 变形 (z) = Δν 温度,变形 (z) - Δν 温度 (z).

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