Device for measuring circumferential stress and ground stress of hole

Abstract

The utility model discloses a device for measuring circumferential stress and ground stress of a hole. The device comprises a plurality of stress measuring pieces, a hydraulic jacking device, a communication line and a data acquisition instrument, the plurality of stress measuring pieces are uniformly distributed along the circumferential direction of the measuring hole and are used for monitoring the stress of the measuring point; the hydraulic jacking device is connected with the hydraulic pump and is used for applying uniform pressure to the plurality of stress measuring pieces to enable the stress measuring pieces to cling to a measuring point; the plurality of stress measuring pieces are electrically connected with a data acquisition instrument through communication lines, and the data acquisition instrument is arranged at the opening of the side hole and is used for receiving monitoring data of the stress measuring pieces in real time. According to the utility model, the stress monitoring is not influenced by materials, layout and construction, and the accuracy of the monitoring result is high.

Description

Technical Field

[0001] This utility model relates to the field of stress monitoring device technology, and in particular to a measuring device for circumferential stress in holes and ground stress. Background Technology

[0002] When monitoring boreholes under external pressure or load, it is necessary to know the irregular deformation stress of the boreholes. The existing measurement method is to drill a borehole and install one or more stress sensors. However, the sensor body contacts the borehole through the curing of concrete grout. This measurement value may be affected by the concrete structure (such as expansion), which can affect the accuracy of the measurement results. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a measuring device for circumferential stress and ground stress in holes. This device is not affected by materials, layout, or construction when monitoring stress, and the monitoring results are highly accurate.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] A measuring device for circumferential and ground stress in cavities includes multiple stress measuring elements, a hydraulic jacking device, a communication line, and a data acquisition instrument;

[0006] Multiple stress measuring elements are evenly distributed along the circumference of the measuring hole to monitor the stress at the measuring point;

[0007] The hydraulic lifting device is connected to the hydraulic pump and is used to apply uniform pressure to multiple stress measuring components to make the stress measuring components fit tightly against the measuring points.

[0008] Multiple stress measuring elements are electrically connected to a data acquisition instrument via communication lines. The data acquisition instrument is installed at the side hole opening to receive monitoring data from the stress measuring elements in real time.

[0009] Furthermore, the stress measuring device is a patch stress gauge.

[0010] Furthermore, the hydraulic lifting device includes an oil chamber, multiple cylinders and a piston rod disposed within the cylinders. The first ends of the multiple cylinders are all connected to the oil chamber, and the oil chamber is connected to the hydraulic pump to supply oil to the multiple cylinders synchronously.

[0011] The piston rod is disposed inside the cylinder, and the first end of the piston rod extends from the second end of the cylinder. The stress measuring element is fixedly disposed at the first end of the piston rod.

[0012] Furthermore, the stress measuring element is welded to the first end of the piston rod.

[0013] Furthermore, it also includes a push rod, on which the hydraulic lifting device is fixed.

[0014] Furthermore, it also includes a pressure gauge for detecting the pressure in the oil chamber. The hydraulic lifting device is connected to the hydraulic pump via a hydraulic pipe. The hydraulic pipe is equipped with a T-connector, and the pressure gauge is connected to the hydraulic pipe via the T-connector.

[0015] Furthermore, it also includes a tilt sensor and a temperature sensor, which are disposed at the end of the first end of the piston rod.

[0016] The beneficial effects of this utility model are:

[0017] This invention is unaffected by materials, layout, or construction when performing stress monitoring, and the monitoring results are highly accurate. It ensures the multidirectionality of stress points and is easy to install. The numerical data from multiple sensors, including pressure, stress, angle, and temperature sensors, can be used for verification. It can also be used in various ways, as a single-point device or a multi-point device in series, and can be applied to long-term stress monitoring in various types of holes, pipe cavities, and underground spaces. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the measuring device for circumferential and ground stress of holes in this embodiment of the present invention;

[0019] Figure 2 A three-dimensional view of the hydraulic jacking device;

[0020] Figure 3 for Figure 1 A cross-sectional view of the hydraulic jacking device along direction AA;

[0021] In the diagram, 1. Stress measuring component; 2. Hydraulic jacking device; 3. Communication line; 4. Hydraulic pump; 5. Oil chamber; 6. Cylinder; 7. Piston rod; 8. Push rod; 9. Pressure gauge; 10. Check valve; 11. Hydraulic pipe; 12. T-joint; 13. Groove; 14. Pin. Detailed Implementation

[0022] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0023] See Figures 1-3 This utility model provides a technical solution:

[0024] Example:

[0025] like Figures 1-3As shown, a measuring device for circumferential and ground stress of a borehole includes six stress measuring elements 1 (stress measuring elements 1 are patch stress gauges). The six stress measuring elements 1 are evenly distributed along the circumference of the borehole and are used to monitor the stress at the measuring points. The six stress measuring elements 1 are electrically connected to a data acquisition instrument via communication lines 3. The data acquisition instrument is set at the side borehole opening to receive the monitoring data of the stress measuring elements 1 in real time.

[0026] like Figure 2 and Figure 3 As shown, a hydraulic lifting device 2 is connected to a hydraulic pump 4 and is used to apply uniform pressure to six stress measuring elements 1 to ensure that the stress measuring elements 1 are in close contact with the measuring points. The hydraulic lifting device 2 includes an oil chamber 5, six cylinders 6, and a piston rod 7 disposed within each cylinder 6. The first end of each of the six cylinders 6 is connected to the oil chamber 5, which is connected to the hydraulic pump 4 to provide synchronous oil supply to the six cylinders 6. The piston rod 7 is disposed within the cylinder 6, with its first end extending from the second end of the cylinder 6. The stress measuring element 1 is welded to the first end of the piston rod 7. An angle sensor and a temperature sensor are also fixed to the first end of the piston rod 7. The angle sensor is used to detect whether the hydraulic lifting device 2 has shifted, and the temperature sensor is used to detect the temperature at the measuring points for long-term monitoring.

[0027] It also includes a push rod 8, on which the hydraulic lifting device 2 is fixed. Six stress measuring elements 1 and the hydraulic lifting device 2 are grouped together, and multiple groups are set up. Each group of stress measuring elements 1 and the hydraulic lifting device 2 are connected in series along the axial direction of the measuring hole via a hydraulic rod. In this way, measuring points at different depths of the measuring hole can be measured. At the same time, the stress measuring elements 1 are sent to the designated measuring point by the push rod 8, which is convenient and fast.

[0028] It also includes a pressure gauge 9 for detecting the pressure of the oil chamber 5. The hydraulic lifting device 2 is connected to the hydraulic pump 4 through a hydraulic pipe 10. The hydraulic pipe 10 is equipped with a three-way connector 11 and a check valve 9. The pressure gauge 9 is connected to the hydraulic pipe 10 through the three-way connector 11.

[0029] 1. The patch stress gauge and the hydraulic jacking device 2 are welded together as one unit, with signal lines reserved. Then, a multi-core cable communication line 3 is used to pull the data lines of the six patch stress gauges to the data acquisition instrument at the tunnel entrance for measurement. The multi-core cable signal line is also connected to the tilt angle and temperature sensors. 2. The patch stress gauge, pressure gauge 9, angle sensor, and temperature sensor are all automatically acquired. The data signal lines of the four devices can be integrated into the automated acquisition equipment.

[0030] Taking a mountain tunnel project as an example: tunnels are constructed in high-stress mountain areas. First, boreholes are drilled in the monitoring area. After drilling is completed, each device is assembled (including the connection of signal lines and pressure gauge 9). After assembly, the entire device is sent to the designated measuring point by push rod 8.

[0031] After the device reaches the measuring point, start the hydraulic pump 4 and observe the pressure gauge 9 until the hydraulic pump 4 pressurizes the oil to the specified pressure. During the pressurization process, since the six cylinders 6 are connected to the oil chamber 5, the pressure in the six cylinders 6 is consistent, and the six piston rods 7 extend synchronously until the stress measuring element 1 is lifted onto the wall of the side hole (i.e., the measuring point). When the oil pressure stabilizes, lock the check valve 9 and remove the hydraulic pump 4 to keep the pressure inside the cylinder 6 constant.

[0032] After the stress measuring component 1 contacts the borehole wall, the patch stress gauge is welded and installed on the front end of the hydraulic jacking device 2. When subjected to stress changes, the patch stress gauge only experiences unidirectional changes in deformation stress (wherein, the hydraulic jacking device 2 is a unidirectional jacking device, with a ratchet groove in the middle of the cylinder inner wall, and a radial telescopic hole at the end of the piston rod 7 near the oil chamber 5, with a ratchet pin adapted to the ratchet groove inside the telescopic hole, and a spring between the ratchet pin and the bottom of the telescopic hole. When the piston rod is jacked (extended), the ratchet pin is squeezed and retracted into the telescopic hole by the cylinder wall. When the ratchet pin aligns with the ratchet groove, the ratchet pin extends into the ratchet groove under the action of the spring, thereby locking the piston rod and making it a rigid rod that cannot retract). The hydraulic jacking device 2 is a fixed point. When the mountain or the pipe experiences compressive stress, a numerical increment change is generated on the patch stress gauge, and this increment change is the current value of the ground stress or the circumferential stress of the borehole.

[0033] When multiple devices of this application are used in series, they can measure ground stress and circumferential stress of pipelines at different depths.

[0034] This invention is unaffected by materials, layout, or construction when performing stress monitoring, and the monitoring results are highly accurate. It ensures the multidirectionality of stress points and is easy to install. The numerical data from multiple sensors, including pressure, stress, angle, and temperature sensors, can be used for verification. It can also be used in various ways, as a single-point device or a multi-point device in series, and can be applied to long-term stress monitoring in various types of holes, pipe cavities, and underground spaces.

[0035] The above description is merely a preferred embodiment of this utility model. It should be understood that this utility model is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of this utility model should be protected within the scope of the appended claims.

Claims

1. A measuring device for circumferential and geostress measurements of pores, characterized in that: Includes multiple stress measuring components, a hydraulic lifting device, communication lines, and a data acquisition instrument; Multiple stress measuring elements are evenly distributed along the circumference of the measuring hole to monitor the stress at the measuring point; The hydraulic lifting device is connected to the hydraulic pump and is used to apply uniform pressure to multiple stress measuring components to make the stress measuring components fit tightly against the measuring points. Multiple stress measuring elements are electrically connected to a data acquisition instrument via communication lines. The data acquisition instrument is installed at the side hole opening to receive monitoring data from the stress measuring elements in real time.

2. The measuring device for circumferential and geostress measurements of pores according to claim 1, characterized in that: The stress measuring device is a patch stress gauge.

3. The measuring device for circumferential and geostress measurements of pores according to claim 2, characterized in that: The hydraulic lifting device includes an oil chamber, multiple cylinders and a piston rod disposed within the cylinders. The first end of each of the multiple cylinders is connected to the oil chamber, and the oil chamber is connected to the hydraulic pump to supply oil to the multiple cylinders synchronously. The piston rod is disposed inside the cylinder, and the first end of the piston rod extends from the second end of the cylinder. The stress measuring element is fixedly disposed at the first end of the piston rod.

4. The measuring device for circumferential and geostress measurements of pores according to claim 3, characterized in that: The stress measuring element is welded to the first end of the piston rod.

5. The measuring device for circumferential and geostress measurements of pores according to claim 3, characterized in that: It also includes a push rod, on which the hydraulic lifting device is fixed.

6. The measuring device for circumferential and geostress measurements of pores according to claim 3, characterized in that: It also includes a pressure gauge for detecting the pressure in the oil chamber. The hydraulic lifting device is connected to the hydraulic pump via a hydraulic pipe. A T-connector is provided on the hydraulic pipe, and the pressure gauge is connected to the hydraulic pipe via the T-connector.

7. The measuring device for circumferential and geostress measurements of pores according to claim 6, characterized in that: It also includes a tilt sensor and a temperature sensor, which are disposed at the end of the first end of the piston rod.

8. The measuring device for circumferential and geostress of a cavity according to claim 7, characterized in that: The hydraulic pipe is equipped with a check valve.

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