Telescoping device for embedding sensors in existing underground structures and method of operation

Abstract

This invention discloses a telescopic device and its operating method for burying sensors in existing underground structures. The telescopic device includes: telescopic rods, comprising a plurality of telescopic rods A and a plurality of telescopic rods B, which are connected at intervals, with each telescopic rod A having both ends slidably fitted onto a corresponding telescopic rod B; a plurality of telescopic rod fastening devices, each used to fix one connected telescopic rod A and one telescopic rod B; and a sensor fastening device, fixed to one or more telescopic rods A or B, used to secure the sensor. This invention effectively secures the sensor, solving problems such as unstable placement of sensors deep within the structure, susceptibility to data cable traction, and soil interference leading to sensor tilting. The telescopic device is simple to operate, efficient to install, and easy to transport. Its length can be flexibly adjusted to meet measurement needs at different depths, and the device can be recycled after measurement.

Description

Technical Field

[0001] This invention relates to the field of in-situ testing and exploration in geotechnical engineering, specifically to a telescopic device and operating method for burying sensors in existing underground structures. Background Technology

[0002] Currently, the most mature and widely used methods for embedding sensors in existing underground structures include the hanging method, the jacking method, and the pop-out method. However, traditional embedding methods suffer from problems such as incompatibility between the sensor and the lateral deformation of the soil after the sensor is embedded, as well as sensor position misalignment, which affects the accuracy of the test results. Furthermore, using steel cages to embed sensors makes them difficult to pull out and reuse, and the sensors need to be welded to the steel cage on-site, making standardized assembly impossible and resulting in low installation efficiency. Improving the efficiency of sensor embedding and the accuracy of sensor test data would have significant engineering implications. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a telescopic device and operating method for burying sensors in existing underground structures, thereby at least solving the problem of sensor position offset.

[0004] A telescopic device for burying sensors in existing underground structures, comprising: Telescopic rod (1), including several telescopic rods A and several telescopic rods B, with several telescopic rods A and several telescopic rods B connected at intervals, and each telescopic rod A having both ends slidably fitted onto a corresponding telescopic rod B; Several telescopic rod fastening devices (2), each telescopic rod fastening device (2) is used to fix a connected telescopic rod A and a telescopic rod B respectively; The sensor fastening device (3) is fixed to the telescopic rod A or telescopic rod B. The sensor fastening device (3) is used to fix the sensor (4).

[0005] Furthermore, the cross-sections of the telescopic rod A and the telescopic rod B are circular, the inner diameter of the telescopic rod A is provided with a groove, and the outer diameter of the telescopic rod B is provided with a groove; the grooves of the telescopic rod A and the telescopic rod B are adapted to each other to enable relative rotation between the telescopic rod A and the telescopic rod B.

[0006] Furthermore, the telescopic rod fastening device (2) includes: Outer profile (2-1), fitted onto telescopic rod A and close to the end of telescopic rod A; A cam lever (2-2) is rotatably mounted on the outer contour (2-1), and the cam lever (2-2) has a variable radius; The pressure block (2-3) is located between the cam lever (2-2) and the telescopic rod (1); After the cam lever (2-2) rotates, the radius of the cam that contacts the pressure block (2-3) gradually increases, which increases the force between the pressure block (2-3) and the telescopic rods A and B, and restricts the relative sliding of the telescopic rods A and B; or the radius of the cam that contacts the pressure block (2-3) gradually decreases, which decreases the force between the pressure block (2-3) and the telescopic rods A and B, and releases the sliding restriction on the telescopic rods A and B.

[0007] Furthermore, the sensor fastening device (3) includes: An embedded housing (3-1) is adapted to the sensor (4), and the embedded housing (3-1) is provided with a cutout (3-3) for the line (4-1) of the sensor to pass through. The connecting device (3-2) is fixed to the embedded housing (3-1) and is used to fix the telescopic rod A or telescopic rod B.

[0008] Furthermore, the connecting device (3-2) uses a self-locking cable tie, a detachable metal hose clamp (3a) or an American-style hose clamp (3b) to fix the sensor (2) to the telescopic rod (1).

[0009] Furthermore, the sensor (4) includes one or more of soil pressure sensor, pore water pressure sensor, and displacement sensor; the sensor (4) is a wired or wireless sensor.

[0010] Furthermore, the telescopic rod A and telescopic rod B are hollow (1-2), and the telescopic rod A and telescopic rod B are provided with openings (1-1), through which the sensor line (4-1) passes into the hollow (1-2).

[0011] Furthermore, the cross-sections of the telescopic rod A and telescopic rod B are polygonal.

[0012] Furthermore, the telescopic rod (1) is made of metal or polymer composite material.

[0013] A method for operating a telescopic device for burying sensors in existing underground structures includes the following steps: (1) Select in-situ test points in the monitoring area, and use wall-protecting mud to drill holes to a depth H in the soil. The diameter D of the hole is greater than the diameter D1 of the telescopic rod so that the telescopic device can be buried in the hole. (2) Connect telescopic rod A and telescopic rod B to the target depth H. By tightening the cam lever of the fastening device on the outside of telescopic rod A, the pressure block is brought into contact with the telescopic rod, thus fixing telescopic rod A and telescopic rod B together. (3) Place the sensor in the housing of the sensor fastening device, and place the sensor on the telescopic rod by tightening the fastening device of the connecting device at the measurement position; for wired sensors, the wire passes through the hole in the housing of the sensor fastening device, passes through the hole on the telescopic rod near the sensor, passes through the hollow part of the telescopic rod, and finally connects to the ground display device. (4) Lower the telescopic rod with the sensor installed into the borehole, check the depth and direction of the sensor, fix the telescopic device on the ground, and backfill the soil in the borehole to the ground. (5) After the backfill soil has been consolidated, relevant data on the soil at each stage will be collected on the ground according to the construction conditions.

[0014] The present invention achieves the following technical effects compared to the prior art: (1) It effectively fixes the sensor, avoids changes in the sensor position during placement, improves the sensor deployment accuracy, and accurately measures the relevant data of the soil.

[0015] (2) The sensor fastening device can securely mount the sensor on the telescopic rod.

[0016] (3) The telescopic device can be manufactured and processed in a standardized manner to control the length of the telescopic rod and the position of the opening. Compared with conventional methods, this device is easier to use, quick to install and easy to transport.

[0017] (4) The total length of the telescopic pole can be adjusted on-site according to the actual measurement needs of the project, thus meeting the needs of different depth related measurements. It is simple to operate, efficient to install, and has good engineering application value and application prospects.

[0018] (5) The device can be designed using wired or wireless sensors as needed. For wired sensors, the wiring can be routed through the hollow interior of the telescopic pole, avoiding the influence of the soil on the wiring during the installation and measurement process.

[0019] (6) It can be used for long-term monitoring or monitoring of temporary structures. After the measurement process is completed, it can be recycled to reduce the cost of measurement.

[0020] The invention has proven to be highly effective in engineering practice. It is simple, efficient to install, and easy to operate, and has been successfully applied in soil pressure monitoring for foundation pit projects. Attached Figure Description

[0021] Figure 1 This is a schematic diagram (circular cross-section) of a telescopic device used for burying sensors in existing underground structures.

[0022] Figure 2This is a schematic diagram of the telescopic rod fastening device for a telescopic device used to install sensors on existing underground structures.

[0023] Figure 3 This is a schematic diagram of the sensor fastening device (removable metal hose clamp) for the telescopic device used to install sensors on existing underground structures.

[0024] Figure 4 This is a schematic diagram of a sensor fastening device (American-style hose clamp) used for telescopic devices to install sensors on existing underground structures.

[0025] Figure 5 This is a schematic diagram of the overall structure of a telescopic device used for burying sensors in existing underground structures (circular cross-section).

[0026] Figure 6 This is a plan view of the foundation pit and a distribution map of earth pressure cell measuring points.

[0027] Figure 7 This is the result of earth pressure monitoring.

[0028] In the figure: telescopic rod (1), hole (1-1), hollow part (1-2), telescopic rod (A), telescopic rod (B), telescopic rod fastening device (2), outer contour (2-1), cam lever (2-2), pressure block (2-3), sensor fastening device (3), outer shell (3-1), connecting device (3-2), outer shell hole (3-3), detachable metal hose clamp (3a), spiral fastening device (3a-1), bayonet (3a-2), American-style hose clamp (3b), fastening device (3b-1), rubber (3b-2), sensor (4), sensor wire (4-1). Detailed Implementation

[0029] The present invention will now be described in more detail with reference to the accompanying drawings, which illustrate preferred embodiments of the invention. It should be understood that those skilled in the art can modify the invention described herein while still achieving its advantageous effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the invention.

[0030] The following description, in conjunction with the accompanying drawings, further illustrates an embodiment of the telescopic device for burying sensors in existing underground structures according to an embodiment of the present invention. The telescopic device of the present invention, used for burying sensors in existing underground structures, is installed around the perimeter of a foundation pit group to monitor soil pressure on site. The site soil pressure test is as follows: Figure 6-7 As shown.

[0031] like Figures 1 to 5 As shown, a telescopic device for burying sensors in existing underground structures according to an embodiment of the present invention includes... Telescopic rod 1 includes several telescopic rods A and several telescopic rods B, with the telescopic rods A and B connected at intervals, and each telescopic rod A having both ends slidably fitted onto a corresponding telescopic rod B; Several telescopic rod fastening devices 2, each telescopic rod fastening device 2 is used to fix a connected telescopic rod A and a telescopic rod B respectively; Sensor fastening device 3 is fixed to telescopic rod A or telescopic rod B. Sensor fastening device 3 is used to fix sensor 4.

[0032] The inner diameter R1 of telescopic rod A is slightly larger than the outer diameter R2 of telescopic rod B. Telescopic rod B is nested inside telescopic rod A. The two telescopic rods A and B can slide against each other. Telescopic rod A and telescopic rod B are fixed by fastening device 2. Telescopic rod A is connected to telescopic rod B on both sides, and telescopic rod B is connected to telescopic rod A on both sides.

[0033] The telescopic pole 1 can be manufactured in the factory according to certain specifications, including the hole design r, the pole length l, the pole cross-sectional dimensions R, etc., and the total connection length L of the two telescopic poles 1 can be adjusted according to the actual engineering site test total depth H and test position.

[0034] In at least one embodiment, the cross-sections of the telescopic rod A and the telescopic rod B are circular, the inner diameter of the telescopic rod A is provided with a groove, and the outer diameter of the telescopic rod B is provided with a groove; the grooves of the telescopic rod A and the telescopic rod B are adapted to each other to allow relative rotation between the telescopic rod A and the telescopic rod B.

[0035] In other embodiments, the cross-sections of the telescopic rod A and telescopic rod B can be other shapes, such as polygons.

[0036] The telescopic rod fastening device 2 includes: Outer profile 2-1, fitted onto telescopic rod A and close to the end of telescopic rod A; A cam lever 2-2 is rotatably mounted on the outer contour 2-1, and the cam lever 2-2 has a variable radius; Pressure block 2-3 is located between cam lever 2-2 and telescopic rod 1; After the cam lever 2-2 rotates, the radius of the cam that contacts the pressure block 2-3 gradually increases, which increases the force between the pressure block 2-3 and the telescopic rods A and B, and restricts the relative sliding of the telescopic rods A and B; or the radius of the cam that contacts the pressure block 2-3 gradually decreases, which decreases the force between the pressure block 2-3 and the telescopic rods A and B, and releases the sliding restriction on the telescopic rods A and B.

[0037] Pressure blocks 2-3 are installed on the outer sides of both ends of telescopic rod A, so that pressure blocks 2-3 can contact telescopic rod B.

[0038] The sensor fastening device 3 includes: An embedded housing 3-1 is adapted to the sensor 4. The embedded housing 3-1 has a cutout 3-3 for the line 4-1 of the sensor to pass through. The connecting device 3-2 is fixed to the embedded housing 3-1 and is used to fix it to the telescopic rod A or telescopic rod B.

[0039] The connecting device 3-2 uses a self-locking cable tie, a detachable metal hose clamp 3a, or an American-style hose clamp 3b to fix the sensor 2 to the telescopic rod 1.

[0040] The sensor fastening device 3 is designed with an embedded housing 3-1 with a radius of r2, which matches the radius r1 of the sensor 4 (r2 is slightly larger than r1). The sensor 4 can be completely embedded in the housing 3-1 without affecting the measurement of the sensor 4. The housing 3-1 has a hole 3-3, through which the wired sensor line 4-1 can pass. The outer side of the housing 3-1 is provided with a connecting device 3-2. When the cross-section of the telescopic rod 1 is circular, the connecting device 3-2 can be a self-locking cable tie, a detachable metal hose clamp 3a, or an American-style hose clamp 3b to fix the sensor 2 to the telescopic rod 1.

[0041] The sensor 4 includes one or more of soil pressure sensors, pore water pressure sensors, and displacement sensors; the sensor 4 can be a wired or wireless sensor.

[0042] The telescopic rods A and B are hollow (1-2), and each has an opening (1-1). The sensor circuit 4-1 passes through the opening (1-1) into the hollow (1-2). It can be understood that when using a wireless sensor, the telescopic rods A and B can also be solid.

[0043] The telescopic pole 1 is made of metal or polymer composite material so that it will not bend or have insufficient strength when placed underground.

[0044] A method for operating a telescopic device for burying sensors in existing underground structures includes the following steps: (1) Select in-situ test points in the monitoring area, and use wall-protecting mud to drill holes to a depth H in the soil. The diameter D of the hole is greater than the diameter D1 of the telescopic rod 1 so that the telescopic device can be buried in the hole. (2) Connect telescopic rod A and telescopic rod B to the target depth H. By tightening the cam lever 2-2 of the fastening device on the outside of telescopic rod A, the pressure block 2-3 contacts the telescopic rod 1, thus fixing the telescopic rod A and telescopic rod B together. (3) Place the sensor 4 in the housing 3-1 of the sensor fastening device 3, and place the sensor 4 on the telescopic rod 1 by tightening the fastening devices 3a-1 and 3b-1 of the connecting device 3-2 at the measurement position; for the wired sensor 4, its line passes through the hole 3-3 in the housing of the sensor fastening device, passes through the hole 1-1 on the telescopic rod 1 near the sensor 4, passes through the hollow part 1-2 of the telescopic rod 1, and finally connects to the ground display device; (4) Lower the telescopic rod 1 with sensor 4 installed into the borehole, check the depth and direction of sensor 4, fix the telescopic device on the ground, and backfill the soil in the borehole to the ground. (5) After the backfill soil has been consolidated, relevant data on the soil at each stage will be collected on the ground according to the construction conditions.

[0045] Telescopic pole 1 can be manufactured and drilled in the factory and then transported to the monitoring location.

[0046] like Figure 6-7 As shown, the telescopic device of this invention, used for burying sensors in existing underground structures, is used for engineering monitoring of a foundation pit excavation project. The foundation pit has an excavation depth of approximately 18.5m, an excavation width of 51m, a retaining wall embedment depth of 50.5m, and a distance between the foundation pit and the surrounding underground structures. B The length is 12m. A soil pressure gauge is installed every 5m along the telescopic pole, and the monitoring results are shown in the figure.

[0047] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A telescopic device for burying sensors in existing underground structures, characterized in that, include: Telescopic rod (1), including several telescopic rods A and several telescopic rods B, with several telescopic rods A and several telescopic rods B connected at intervals, and each telescopic rod A having both ends slidably fitted onto a corresponding telescopic rod B; Several telescopic rod fastening devices (2), each telescopic rod fastening device (2) is used to fix a connected telescopic rod A and a telescopic rod B respectively; The sensor fastening device (3) is fixed to the telescopic rod A or telescopic rod B. The sensor fastening device (3) is used to fix the sensor (4). The sensor fastening device (3) includes: An embedded housing (3-1) is adapted to the sensor (4), and the embedded housing (3-1) is provided with a cutout (3-3) for the line (4-1) of the sensor to pass through. The connecting device (3-2) is fixed to the embedded housing (3-1) and is used to fix it to telescopic rod A or telescopic rod B; The telescopic rod A and telescopic rod B are hollow parts (1-2), and the telescopic rod A and telescopic rod B are provided with openings (1-1). The sensor line (4-1) passes through the opening (1-1) into the hollow part (1-2). The telescopic rod fastening device (2) includes: Outer profile (2-1), fitted onto telescopic rod A and close to the end of telescopic rod A; A cam lever (2-2) is rotatably mounted on the outer contour (2-1), and the cam lever (2-2) has a variable radius; The pressure block (2-3) is located between the cam lever (2-2) and the telescopic rod (1); After the cam lever (2-2) rotates, the radius of the cam that contacts the pressure block (2-3) gradually increases, which increases the force between the pressure block (2-3) and the telescopic rods A and B, and restricts the relative sliding of the telescopic rods A and B; or the radius of the cam that contacts the pressure block (2-3) gradually decreases, which decreases the force between the pressure block (2-3) and the telescopic rods A and B, and releases the sliding restriction on the telescopic rods A and B.

2. The telescopic device for burying sensors in existing underground structures according to claim 1, characterized in that, The cross-sections of telescopic rod A and telescopic rod B are circular. The inner diameter of telescopic rod A is provided with a groove, and the outer diameter of telescopic rod B is provided with a groove. The grooves of telescopic rod A and telescopic rod B are adapted to each other to restrict the relative rotation between telescopic rod A and telescopic rod B.

3. The telescopic device for burying sensors in existing underground structures according to claim 1, characterized in that, The connecting device (3-2) uses a self-locking cable tie, a detachable metal hose clamp (3a) or an American-style hose clamp (3b) to fix the sensor (4) to the telescopic rod (1).

4. The telescopic device for burying sensors in existing underground structures according to claim 1, characterized in that, The sensor (4) includes one or more of soil pressure sensor, pore water pressure sensor, and displacement sensor; the sensor (4) is a wired or wireless sensor.

5. The telescopic device for burying sensors in existing underground structures according to claim 1, characterized in that, The cross-sections of telescopic rods A and B are polygonal.

6. The telescopic device for burying sensors in existing underground structures according to claim 1, characterized in that, The telescopic rod (1) is made of metal or polymer composite material.

7. A method for operating a telescopic device for burying sensors in existing underground structures as described in any one of claims 1-6, characterized in that, Includes the following steps: (1) Select in-situ test points in the monitoring area, and use wall-protecting mud to drill to a depth H in the soil. The diameter D of the borehole is greater than the diameter D1 of the telescopic rod (1) so that the telescopic device can be buried in the borehole. (2) Connect telescopic rod A and telescopic rod B to the target depth H. By tightening the cam lever (2-2) of the telescopic rod fastening device on the outside of telescopic rod A, the pressure block (2-3) contacts the telescopic rod (1) to fix the telescopic rod A and telescopic rod B. (3) Place the sensor (4) in the embedded housing (3-1) of the sensor fastening device (3), and place the sensor (4) on the telescopic rod (1) by tightening the fastening device (3a-1, 3b-1) of the connecting device (3-2) at the measurement position; for wired sensor (4), its line passes through the hole (3-3) in the embedded housing of the sensor fastening device, passes through the opening (1-1) on the telescopic rod (1) near the sensor (4), passes through the hollow part (1-2) of the telescopic rod (1), and finally connects to the ground display device; (4) Place the telescopic rod (1) with the sensor (4) installed downward into the borehole, check the depth and direction of the sensor (4), fix the telescopic device on the ground, and backfill the soil in the borehole to the ground. (5) After the backfill soil has been consolidated, relevant data on the soil at each stage will be collected on the ground according to the construction conditions.

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