High-precision settlement measuring instrument based on displacement sensor and construction method

Abstract

The present application relates to a precision instrument foundation high-precision settlement measuring instrument based on a displacement sensor, comprising a foundation connector fixed on a device foundation, a settlement measuring instrument arranged on the foundation connector, an end bearing pile arranged at the bottom of the settlement measuring instrument, the end bearing pile being located at the upper part of the top surface of the bottom plate, and a heat insulation protective cover arranged outside the settlement measuring instrument; the foundation connector comprises a right-angle connecting steel plate, a measuring instrument mounting hole for mounting the settlement measuring instrument is formed on the top surface of the right-angle connecting steel plate, a plurality of connecting bolt holes are formed around the measuring instrument mounting hole, and the side wall of the right-angle connecting steel plate is fixed with the device foundation; the settlement measuring instrument comprises a fixing member and a displacement sensor arranged at the lower part of the fixing member, the fixing member is connected with the right-angle connecting steel plate, a sensor connector is arranged at the lower part of the fixing member, a displacement sensor is arranged at the lower part of the sensor connector, and the displacement sensor comprises a hollow rod and a measuring probe arranged at the bottom of the hollow rod.

Description

Technical Field

[0001] This invention relates to a high-precision settlement measuring instrument and construction method based on a displacement sensor for precision instrument foundations, which is applied in the field of civil engineering technology. Background Technology

[0002] As is well known, under the combined effects of equipment weight and soil creep, equipment foundations may experience uniform or uneven settlement, leading to equipment tilting and altered stress conditions. For high-precision instruments or equipment (such as substation main transformers, radio telescopes, and power generation (nuclear power) units), this can even cause equipment accidents, resulting in significant property damage. To ensure the safety of structures during construction and operation, and to avoid economic losses and personal injury, foundation settlement monitoring should be prioritized. Settlement monitoring is a crucial means of controlling and providing early warning of foundation settlement.

[0003] However, current common methods for monitoring settlement involve using optical instruments such as total stations and theodolites to measure the elevation of the point to be measured from known points. But these methods have the following shortcomings:

[0004] 1. Line of sight requirement: When using optical equipment for measurement, the operating point and the point to be measured must be in line of sight. However, the equipment foundation is usually protected by shielding, making operation difficult. In addition, the known point usually needs to be moved through multiple stations, resulting in a significant loss of accuracy.

[0005] 2. Insufficient accuracy: Optical instruments use light wave reflection and timers for measurement, but the speed of light in the air is difficult to determine accurately, and the accuracy of clock instruments is limited (at the order of the speed of light). It is difficult for optical ranging to achieve ultra-high accuracy. Taking the ZTS-421L10 total station (second level) produced by Hi-Target as an example, its ranging accuracy is ±1mm+1ppm. Even high-precision instruments can only achieve ±0.5mm+1ppm (half-second level), which is almost the limit of optical equipment.

[0006] 3. Reliance on handheld prisms: Optical instruments (total stations) rely heavily on reflective prisms when performing high-precision measurements. The high precision mentioned above can only be achieved with the assistance of prisms. Without prisms, the accuracy can only reach ±3mm + 2ppm. However, when important instruments and equipment such as main transformers and nuclear power units are running, it is not allowed for personnel to carry prisms into the equipment, and the machine must be stopped for measurement. This greatly limits the frequency of settlement measurement.

[0007] In addition, the automation costs and environmental requirements of optical measuring instruments are high, making it difficult to achieve continuous real-time monitoring of settlement.

[0008] An invention patent with announcement number CN114753418A discloses a settlement and tilt measurement and monitoring device for deep foundation pit engineering in civil construction. Specifically, it discloses that when the fixed plate tilts, multiple counterweight balls tilt synchronously, causing multiple airbags to deform, which in turn drives the first plate to slide on the inner wall of the strip cavity. At this time, the displacement sensor can measure the displacement data of the test plate. The settlement and tilt of the deep foundation pit engineering can be measured and detected according to the tilt direction of the fixed plate. This allows technicians to analyze the settlement and tilt of the deep foundation pit engineering without the need for manual operation and measurement, thus reducing labor intensity. However, the structure and settlement measurement principle of this invention are relatively complex, making it very inconvenient to use. Moreover, if any one of the components malfunctions, the entire device will not function properly. Summary of the Invention

[0009] To address the aforementioned technical problems, this invention provides a high-precision settlement measuring instrument based on a displacement sensor and a construction method for such an instrument. The displacement sensor is rigidly connected to the foundation of the equipment under test to achieve settlement transfer. It can be permanently placed at the measurement location without the need for a handheld prism. The data is transmitted via cable, enabling continuous monitoring during equipment operation.

[0010] The technical solution of the present invention is as follows:

[0011] A high-precision settlement measuring instrument based on a displacement sensor includes a foundation connector fixed to the equipment foundation. A settlement measuring instrument is mounted on the foundation connector, and an end-bearing pile is installed at the bottom of the settlement measuring instrument, located on the upper part of the top surface of the base plate. A heat-insulating protective cover is installed outside the settlement measuring instrument. The foundation connector includes a right-angle connecting steel plate. A measuring instrument mounting hole is opened on the top surface of the right-angle connecting steel plate for mounting the settlement measuring instrument. Several connecting bolt holes are opened around the measuring instrument mounting hole. The side wall of the right-angle connecting steel plate is fixed to the equipment foundation. The settlement measuring instrument includes a fixing component and a displacement sensor installed at the lower part of the fixing component. The fixing component is connected to the right-angle connecting steel plate. A sensor connector is installed at the lower part of the fixing component, and a displacement sensor is installed at the lower part of the sensor connector. The displacement sensor includes a hollow rod and a measuring probe installed at the bottom of the hollow rod. A data cable is connected to the upper part of the measuring probe.

[0012] The equipment base has several pre-drilled screw holes for fixing right-angle connecting steel plates. The side wall of the right-angle connecting steel plates has several foundation connection holes that match the pre-drilled screw holes. The right-angle connecting steel plates are fixed to the equipment base by screwing in fastening screws into the pre-drilled screw holes and foundation connection holes.

[0013] The sensor connector is inserted into the measuring instrument mounting hole opened on the top surface of the right-angle connecting steel plate. The fixing part has several through holes that are compatible with the measuring instrument mounting hole. By inserting limiting bolts into the through holes and measuring instrument mounting holes, and setting connecting nuts at the bottom of the limiting bolts, the fixing part is installed on the top surface of the right-angle connecting steel plate.

[0014] The sensor connector has two fixing holes on its side wall and two elongated connecting holes on the top of its side wall. The two elongated connecting holes and the two fixing holes are matched. The hollow rod is embedded in the bottom of the sensor connector by inserting sensor connecting screws into the elongated connecting holes and the fixing holes.

[0015] A column is integrally connected to the center of the fixing component. The upper part of the column is cylindrical, and the lower part is frustum-shaped. The bottom of the column is fixed to the sensor connector, and a cylindrical channel for the data cable to pass through is opened in the middle of the column.

[0016] The heat insulation protective cover is made of tempered glass, with cable through holes on the top surface and side doors on the side walls.

[0017] The data cable at the top of the measuring probe passes sequentially through the hollow rod, the sensor connector, and the column, and finally emerges from the top of the heat insulation protective cover. One end of the data cable is connected to the measuring probe, and the other end is connected to the data acquisition instrument.

[0018] The top of the end-bearing pile is higher than the top surface of the base slab but lower than the ground level by the height of a settlement measuring instrument. Sufficient space should be provided in the foundation's pre-drilled bolt holes according to the position of the end-bearing pile top to allow for instrument installation, ensuring that the measuring probe can make tight contact with the pile top after the instrument is installed, finely adjusted, and locked.

[0019] The construction method of a high-precision settlement measuring instrument based on a displacement sensor is as follows:

[0020] S1: Before the foundation is poured, end-bearing piles with a diameter of 500mm and whose bottom reaches the rock stratum are constructed at the predetermined location as the zero point for settlement measurement.

[0021] S2: By installing embedded pipes in the pre-reserved screw holes in the foundation, aligning the foundation connection holes on the side wall of the right-angle connecting steel plate with the pre-reserved screw holes in the foundation, and inserting fastening screws to fix the foundation connectors on the equipment foundation;

[0022] S3: Install the settlement measuring instrument on the foundation connector. Move the hollow rod up and down to change the connection position between the fixing hole on the side wall of the sensor connector and the elongated connecting hole. Then fix it with the sensor connecting screw and the steel wire limiter to achieve fine adjustment of the displacement sensor length. Install a piece of smooth glass on the top of the end-bearing pile as a measuring point so that the measuring probe at the bottom of the displacement sensor is in close contact with the glass on the top of the end-bearing pile. Then set the data acquisition instrument to zero.

[0023] S4: Install the prefabricated heat insulation protective cover with asbestos insulation layer on the outside of the settlement measuring instrument. Before installation, place quicklime in the heat insulation protective cover to keep it dry. Pass the data cable that comes out from the top of the column through the cable through hole opened on the top surface of the heat insulation protective cover and extend the data cable to a place that is easy to connect. Then cover the outside of the heat insulation protective cover with backfill soil to provide a relatively stable constant temperature environment.

[0024] S5: Regularly carry a data acquisition device and connect it to the data cable at the output end of the settlement measuring instrument to read the displacement sensor readings, thereby achieving settlement measurement without stopping the equipment; or place the data acquisition device in a safe place and keep it connected to the displacement sensor, automatically recording the displacement sensor readings at a fixed frequency to achieve real-time settlement monitoring.

[0025] The present invention has the following beneficial effects:

[0026] This invention applies displacement sensors to the field of settlement measurement technology. It proposes a unique structural design that rigidly connects the displacement sensor to the foundation of the equipment to be measured, thereby transmitting settlement data. The displacement sensor can be permanently placed at the measurement position without the need for a handheld prism. The measurement data is transmitted to a data acquisition instrument via a data cable, enabling continuous monitoring during equipment operation. The displacement sensor utilizes the magnetostrictive principle, generating a strain pulse signal through the intersection of two different magnetic fields to accurately measure the displacement of the probe. This achieves an accuracy advantage of two orders of magnitude (±0.01mm) compared to optical instruments, meeting the monitoring requirements for settlement of high-precision equipment foundations. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the settlement measuring instrument in this invention;

[0028] Figure 2 This is a schematic diagram of the connection structure between the basic connector and the equipment foundation in this invention;

[0029] Figure 3 This is a schematic diagram showing the completed assembly of the settlement measuring instrument, foundation connectors, and equipment foundation in this invention.

[0030] Figure 4 This is a schematic diagram showing the completed installation of the heat insulation protective cover in this invention;

[0031] The reference numerals in the figure are as follows:

[0032] 1. Settlement measuring instrument; 11. Data cable; 12. Limit bolt; 13. Fixing component; 14. Sensor connector; 15. Connecting nut; 16. Sensor connecting screw; 17. Displacement sensor; 171. Hollow rod; 172. Measuring probe; 173. Long strip connecting hole; 2. Foundation connector; 21. Connecting bolt hole; 22. Measuring instrument mounting hole; 23. Right angle connecting steel plate; 24. Fastening screw; 25. Foundation connecting hole; 3. Equipment foundation; 31. Foundation reserved screw hole; 4. Top surface of bottom plate; 5. End bearing pile; 6. Heat insulation protective cover. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0034] See Figures 1 to 4 The high-precision settlement measuring instrument based on a displacement sensor includes a foundation connector 2 fixed to the equipment foundation 3, a settlement measuring instrument 1 mounted on the foundation connector 2, an end-bearing pile 5 at the bottom of the settlement measuring instrument 1 located on the upper part of the top surface 4 of the base plate, and a heat-insulating protective cover 6 on the outside of the settlement measuring instrument 1. The foundation connector 2 includes a right-angle connecting steel plate 23, and a measuring instrument mounting hole 22 for mounting the settlement measuring instrument 1 is opened on the top surface of the right-angle connecting steel plate 23. Around the measuring instrument mounting hole 22 are... There are several connecting bolt holes 21, and the side wall of the right-angle connecting steel plate 23 is fixed to the equipment foundation 3; the settlement measuring instrument 1 includes a fixing part 13 and a displacement sensor 17 set at the lower part of the fixing part 13. The fixing part 13 is connected to the right-angle connecting steel plate 23. A sensor connector 14 is set at the lower part of the fixing part 13. A displacement sensor 17 is set at the lower part of the sensor connector 14. The displacement sensor 17 includes a hollow rod 171 and a measuring probe 172 set at the bottom of the hollow rod 171. A data cable 11 is connected to the upper part of the measuring probe 172.

[0035] The equipment foundation 3 has several foundation reserved screw holes 31 for fixing the right-angle connecting steel plate 23. The side wall of the right-angle connecting steel plate 23 has several foundation connecting holes 25 that are compatible with the foundation reserved screw holes 31. The right-angle connecting steel plate 23 is fixed to the equipment foundation 3 by screwing in fastening screws 24 into the foundation reserved screw holes 31 and the foundation connecting holes 25.

[0036] The sensor connector 14 is inserted into the measuring instrument mounting hole 22 opened on the top surface of the right-angle connecting steel plate 23. The fixing member 13 has several through holes that are compatible with the measuring instrument mounting hole 22. By inserting the limiting bolt 12 into the through hole and the measuring instrument mounting hole 22, and setting the connecting nut 15 at the bottom of the limiting bolt 12, the fixing member 13 is installed on the top surface of the right-angle connecting steel plate 23.

[0037] The sensor connector 14 has two fixing holes on its side wall, and the hollow rod 171 has two elongated connecting holes 173 on its top side wall. The two elongated connecting holes 173 and the two fixing holes are matched. The hollow rod 171 is embedded in the bottom of the sensor connector 14 by inserting sensor connecting screws 16 into the elongated connecting holes 173 and the fixing holes.

[0038] A column is integrally connected to the center of the fixing member 13. The upper part of the column is cylindrical and the lower part is frustum-shaped. The bottom of the column is fixed to the sensor connector 14. A cylindrical channel for the data cable 11 to pass through is opened in the middle of the column.

[0039] The heat insulation protective cover 6 is made of tempered glass. A cable through hole is provided on the top surface of the heat insulation protective cover 6, and a side door is provided on the side wall of the heat insulation protective cover 6.

[0040] The data line 11 on the upper part of the measuring probe 172 passes through the hollow rod 171, the sensor connector 14 and the column in sequence, and finally emerges from the top of the heat insulation protective cover 6. One end of the data line 11 is connected to the measuring probe 172, and the other end of the data line 11 is connected to the data acquisition instrument.

[0041] The top of the end-bearing pile 5 is higher than the top surface 4 of the base slab and lower than the ground level by the height of a settlement measuring instrument 1. This facilitates the covering with backfill. Since the pile is embedded in the rock strata, it can be considered unaffected when the equipment foundation 3 settles, and the top of the pile can be used as the settlement reference surface. The foundation's pre-drilled screw holes 31 should reserve sufficient space for instrument installation based on the position of the top of the end-bearing pile 5, so that after the instrument is installed, finely adjusted, and locked, the measuring probe 172 can make close contact with the top of the pile.

[0042] The construction method of a high-precision settlement measuring instrument based on a displacement sensor is as follows:

[0043] S1: Before the foundation is poured, an end-bearing pile 5 with a diameter of 500mm and the bottom of the pile reaching the rock layer is constructed at the predetermined location as the zero point for settlement measurement.

[0044] S2: By installing a pre-embedded pipe in the pre-reserved screw hole 31 of the foundation, the foundation connection hole 25 on the side wall of the right-angle connecting steel plate 23 is connected with the pre-reserved screw hole 31 of the foundation, and the fastening screw 24 is inserted to fix the foundation connector 2 on the equipment foundation 3.

[0045] S3: Install the settlement measuring instrument 1 on the foundation connector 2, move the hollow rod 171 up and down to change the connection position between the fixing hole on the side wall of the sensor connector 14 and the elongated connecting hole 173, and then fix it with the sensor connecting screw 16 and the steel wire limiter to achieve fine adjustment of the length of the displacement sensor 17. Install a piece of smooth glass on the top of the end-bearing pile 5 as a measuring point so that the measuring probe 172 at the bottom of the displacement sensor 17 is in close contact with the glass on the top of the end-bearing pile 5, and further zero the data acquisition instrument.

[0046] S4: Install the prefabricated heat insulation protective cover 6 with asbestos insulation interlayer on the outside of the settlement measuring instrument 1. Before installation, place quicklime in the heat insulation protective cover 6 to keep it dry, and pass the data cable 11 that passes through the top of the column through the cable through hole opened on the top surface of the heat insulation protective cover 6. Extend the data cable 11 to a place that is easy to connect, and then cover the outside of the heat insulation protective cover 6 with backfill soil to provide a relatively stable constant temperature environment.

[0047] S5: Regularly carry the data acquisition instrument and connect it to the data cable 11 at the output end of the settlement measuring instrument 1 to read the displacement sensor 17, thereby realizing settlement measurement without stopping the equipment; or place the data acquisition instrument in a safe place and keep it connected to the displacement sensor 17, and automatically record the reading of the displacement sensor 17 at a fixed frequency to realize real-time settlement monitoring; or install multiple units of this equipment on the top surface 4 of a base plate to realize the monitoring of uneven settlement.

[0048] During the installation of the settlement measuring instrument 1, the height of the displacement sensor 17 is finely adjusted through the setting of the elongated connecting hole 173, so that the measuring probe 172 of the displacement sensor 17 is closely attached to the top of the end bearing pile 5 and set to zero. When the equipment foundation 3 settles, it will drive the device to settle synchronously. The measuring probe 172 of the displacement sensor 17 will move upward relative to the end bearing pile 5, thereby changing the magnetic field inside the displacement sensor 17. At this time, it is only necessary to use the data acquisition instrument to measure the magnetic field inside the displacement sensor 17 and refer to the calibration table to obtain the displacement of the displacement sensor 17, that is, the foundation settlement.

[0049] The displacement sensor 17 used in this invention is preferably a German BEBIK KTR2 type spring linear displacement sensor with a range of 10mm and an accuracy of 0.01mm. The hollow rod 171 is made of stainless steel, with an outer diameter of 9mm, an inner diameter of 8mm, a wall thickness of 1mm, and a height of 100mm. A smooth, elongated connecting hole 173 with a diameter of 1mm and a height of 7mm is reserved 20mm from the upper end of the hollow rod 171 for the connecting screw 16 to pass through, and can achieve a 5mm up-and-down fine adjustment. The hollow rod 171 and the measuring probe 172 are rigidly connected by welding or other means. The main body 13 is a stainless steel disc with a diameter of 50mm. The fixing part 13 is 2mm thick. The upper part of the central column is a hollow cylinder with an outer diameter of 20mm, an inner diameter of 5mm, and a height of 100mm. The lower part of the column is a stainless steel gradient section with a top outer diameter of 20mm, a bottom outer diameter of 10mm, and an inner diameter of 9mm. Below the column is a cylindrical sensor connector 14 with an outer diameter of 10mm and an inner diameter of 9mm. The stainless steel hollow rod 171 is sleeved together with the sensor connector 14 and fixed with connecting screws 16. The data cable 11 connected to the measuring probe 172 passes through the middle. The base connector 2 is a stainless steel angled steel plate.

[0050] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A high-precision settlement measuring instrument based on a displacement sensor, characterized in that: The system includes a foundation connector (2) fixed on the equipment foundation (3), a settlement measuring instrument (1) installed on the foundation connector (2), an end bearing pile (5) installed at the bottom of the settlement measuring instrument (1), the end bearing pile (5) being located on the upper part of the top surface (4) of the base plate, and a heat insulation protective cover (6) installed on the outside of the settlement measuring instrument (1); the foundation connector (2) includes a right-angle connecting steel plate (23), the top surface of the right-angle connecting steel plate (23) is provided with a measuring instrument mounting hole (22) for installing the settlement measuring instrument (1), and a number of connecting bolt holes (21) are provided around the measuring instrument mounting hole (22). The side wall of the connecting steel plate (23) is fixed to the equipment foundation (3); the settlement measuring instrument (1) includes a fixing part (13) and a displacement sensor (17) set at the lower part of the fixing part (13). The fixing part (13) is connected to the right-angle connecting steel plate (23). A sensor connector (14) is set at the lower part of the fixing part (13). A displacement sensor (17) is set at the lower part of the sensor connector (14). The displacement sensor (17) includes a hollow rod (171) and a measuring probe (172) set at the bottom of the hollow rod (171). A data cable (11) is connected to the upper part of the measuring probe (172).

2. The high-precision settlement measuring instrument based on a displacement sensor as described in claim 1, characterized in that: The equipment foundation (3) has several foundation reserved screw holes (31) for fixing the right-angle connecting steel plate (23). The side wall of the right-angle connecting steel plate (23) has several foundation connection holes (25) that are compatible with the foundation reserved screw holes (31). The right-angle connecting steel plate (23) is fixed on the equipment foundation (3) by screwing in fastening screws (24) into the foundation reserved screw holes (31) and the foundation connection holes (25).

3. The high-precision settlement measuring instrument based on a displacement sensor as described in claim 2, characterized in that: The sensor connector (14) is inserted into the measuring instrument mounting hole (22) opened on the top surface of the right-angle connecting steel plate (23). The fixing part (13) has several through holes that are compatible with the measuring instrument mounting hole (22). By inserting the limiting bolt (12) into the through hole and the measuring instrument mounting hole (22) and setting the connecting nut (15) at the bottom of the limiting bolt (12), the fixing part (13) is installed on the top surface of the right-angle connecting steel plate (23).

4. The high-precision settlement measuring instrument based on a displacement sensor as described in claim 3, characterized in that: The sensor connector (14) has two fixing holes on its side wall, and the hollow rod (171) has two elongated connecting holes (173) on its top side wall. The two elongated connecting holes (173) and the two fixing holes are matched. The hollow rod (171) is embedded in the bottom of the sensor connector (14) by inserting sensor connecting screws (16) into the elongated connecting holes (173) and the fixing holes.

5. The high-precision settlement measuring instrument based on a displacement sensor as described in claim 3, characterized in that: A column is integrally connected to the center of the fixing member (13). The part of the column located on the upper part of the fixing member (13) is cylindrical, and the part of the column located on the lower part of the fixing member (13) is frustum-shaped. The bottom of the column is fixed to the sensor connector (14), and a cylindrical channel for the data cable (11) to pass through is opened in the middle of the column.

6. The high-precision settlement measuring instrument based on a displacement sensor as described in claim 1, characterized in that: The heat insulation protective cover (6) is made of tempered glass. A cable through hole is provided on the top surface of the heat insulation protective cover (6), and a side door is provided on the side wall of the heat insulation protective cover (6).

7. The high-precision settlement measuring instrument based on a displacement sensor as described in claim 1, characterized in that: The data line (11) on the upper part of the measuring probe (172) passes through the hollow rod (171), the sensor connector (14) and the column in sequence, and finally emerges from the top of the heat insulation protective cover (6). One end of the data line (11) is connected to the measuring probe (172), and the other end of the data line (11) is connected to the data acquisition instrument.

8. The high-precision settlement measuring instrument based on a displacement sensor as described in claim 1, characterized in that: The top of the end-bearing pile (5) is higher than the top surface of the bottom plate (4) and lower than the height of a settlement measuring instrument (1) on the ground.

9. A construction method for a high-precision settlement measuring instrument based on a displacement sensor, used for constructing the settlement measuring instrument as described in claim 4, characterized in that: The specific steps are as follows: S1: Before the foundation is poured, an end-bearing pile (5) with a diameter of 500 mm and the bottom of the pile reaching the rock layer is constructed at the predetermined position as the zero point for settlement measurement. S2: By installing the embedded pipe in the pre-reserved screw hole (31) of the foundation, the foundation connection hole (25) of the right angle connecting steel plate (23) side wall is connected with the pre-reserved screw hole (31) of the foundation, and the fastening screw (24) is inserted to fix the foundation connector (2) on the equipment foundation (3); S3: Install the settlement measuring instrument (1) on the foundation connector (2), move the hollow rod (171) up and down to change the connection position of the fixing hole on the side wall of the sensor connector (14) and the long strip connecting hole (173), and then fix it with the sensor connecting screw (16) and the wire limiter to achieve fine adjustment of the length of the displacement sensor (17). Install a piece of smooth glass on the top of the end bearing pile (5) as a measuring point so that the measuring probe (172) at the bottom of the displacement sensor (17) is in close contact with the glass on the top of the end bearing pile (5), and further set the data acquisition instrument to zero. S4: Install the prefabricated heat insulation protective cover (6) with asbestos insulation interlayer on the outside (1) of the settlement measuring instrument. Before installation, place quicklime in the heat insulation protective cover (6) to keep it dry, and pass the data cable (11) through the top of the column through the cable through hole opened on the top surface of the heat insulation protective cover (6). Extend the data cable (11) to a place where it is easy to connect, and then cover the outside of the heat insulation protective cover (6) with backfill to provide a more stable constant temperature environment. S5: Regularly carry a data acquisition instrument and connect the data acquisition instrument to the data line (11) at the output end of the settlement measuring instrument (1) to read the displacement sensor (17), thereby realizing settlement measurement without stopping the equipment; or place the data acquisition instrument in a safe place to maintain the connection with the displacement sensor (17) and automatically record the reading of the displacement sensor (17) at a fixed frequency to realize real-time settlement monitoring.

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