A multi-point displacement measurement device and displacement measurement method for soft soil layers

Abstract

The present application relates to a kind of multi-point displacement measuring device and displacement measuring method for soft soil layer, including anchor head, protection pipe, end head and measurement module;Protection pipe is connected section by section and is driven into soft soil layer using pile driver;There is steel strand in protection pipe, and it is connected with anchor head and measurement module;When anchor head is laid, steel strand can be pulled up to make it spread out and pierce into soil body;When soft soil layer subsides, anchor head moves with soil body, and drives steel strand to pull measurement module optical raster ruler displacement sensor, optical raster ruler displacement sensor can convert displacement data into electrical signal and store in the storage module in measurement module;The present application can be freely combined length to adapt to different depth soft soil layer;And anchor head uses the layout mode of piercing into soil body, can effectively reduce the disturbance to soil body;Protection pipe is driven into soft soil layer using pile driver, can effectively prevent drilling hole collapse and foreign matter drop into when conventional multi-point displacement meter is laid, while greatly saving layout time.

Description

Technical Field

[0001] This invention relates to the field of geotechnical engineering technology, specifically to a multi-point displacement measurement device and displacement measurement method for soft soil strata. Background Technology

[0002] In the field of geotechnical engineering, it is often necessary to study the displacement of multiple parts of the soil within structures, such as earth dams, slopes, tunnels, and foundations. However, the internal deformation of the soil is quite complex, and it is not possible to obtain the internal deformation of the soil directly through external observation. Therefore, it is necessary to install multi-point displacement gauges to obtain the displacement at different locations deep within the soil.

[0003] Currently, the most commonly used multi-point displacement gauges are borehole multi-point displacement gauges. During installation, holes are first drilled into the stratum, then measuring points are fixed and the multi-point displacement gauges are installed. Common measuring point fixing devices include grouting type, spring type, hydraulic support type, and inverted wedge type, etc. However, these fixing methods can cause significant disturbance to soft soil strata, damaging the structure of the soft soil, and resulting in discrepancies between the obtained stratum settlement data and the actual settlement data. Therefore, a reasonable anchor head type and multi-point displacement gauge layout method can ensure the accuracy of settlement data.

[0004] Chinese patent CN103850237A discloses a blade-cutting type multi-point displacement meter anchor head for soft soil. The device includes a central shaft, an outer rod, an upper frame, a lower frame, a clarinet, a force transmission rod, and an anchoring blade. Although the device is designed for soft soil areas, when it is deployed, the anchoring blade cuts into the soil from top to bottom, causing significant disturbance to the soft soil. When the soil settles downwards, the pulling effect on the anchor head is weak.

[0005] Chinese patent CN104457655A discloses a folded blade knife-type multi-point displacement meter anchor head for soft soil strata. The device includes a central shaft, a wall cylinder, a base force transmission rod, and a rocker arm. When unfolded, it cuts into the soil from the side, which can effectively avoid the disadvantage of the soil's weak pulling force on the anchor head. However, the anchor head is large in size and has a complex structure.

[0006] In summary, the existing anchoring head devices and deployment methods are relatively complex and occupy a lot of space; moreover, the existing multi-point displacement gauges are mostly deployed by pre-drilling holes and then lowering the multi-point displacement gauges. In soft soil strata, the holes are prone to collapse or debris may fall in, affecting the deployment of the multi-point displacement gauges. Summary of the Invention

[0007] The purpose of this invention is to provide a multi-point displacement measurement device and displacement measurement method for soft soil strata. The device itself causes little disturbance to the soil and has high accuracy in monitoring displacement at different depths within the soft soil strata.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] The multi-point displacement measurement device for soft soil includes an anchor head, a protective tube, an end head, and a measurement module. The anchor head is vertically installed inside the hollow protective tube, and the protective tube has a male connector and a female connector at both ends. The male connector connects to the end head, and the female connector connects to the measurement module.

[0010] The anchor head includes a strip-shaped anchor base, which includes a left anchor base and a right anchor base; the left and right anchor bases have elongated wire holes; the right anchor base has a slide rail at its edge, and the left and right anchor bases are stacked on top of each other and slidably connected by the slide rail; the wire holes contain vertically movable steel strands; both the left and right anchor bases have fulcrums, and the two fulcrums are connected to a cross brace; the other end of the cross brace is connected to the steel strand; a narrow groove is opened on the vertical protective pipe surface, through which the anchor head can be movably installed.

[0011] There are two or more protective pipes, which are connected to each other by male and female connectors at both ends; there are two or more anchor heads vertically installed inside the protective pipes, and guide plates are installed parallel between the anchor heads, which separate the anchor heads; each anchor head is connected to a steel strand; the guide plate has two or more guide holes, through which steel strands are threaded and supported; both ends of the steel strands are provided with male and female connectors, and the steel strands are connected to each other through the male and female connectors;

[0012] The measurement module includes a protective sleeve for protecting internal components; the sleeve is a cylindrical structure, and a grating ruler displacement sensor is fixedly installed inside the sleeve. One end of the grating ruler displacement sensor is connected to a steel strand, and the other end is connected to a tension spring, which pulls the steel strand and keeps it taut; the steel strand connected to the grating ruler displacement sensor is also slidably connected to a pulley; the grating ruler displacement sensor is connected to a data line, which is connected to a data collector, which stores the displacement data acquired by the grating ruler displacement sensor; an elevation marker is set at the center of the sleeve.

[0013] After the cutting edge penetrates the soft soil layer, if the soil layer deforms and settles, the anchor head moves downward, which in turn pulls the steel strand and drives the grating ruler displacement sensor in the measurement module to move. The data line transmits the displacement data obtained by the grating ruler displacement sensor to the data collector. During the measurement process, the measurement module may settle along with the protective pipe. The settlement amount of the measurement module is continuously obtained through elevation markers, and the settlement data is corrected based on this, thereby obtaining the soft soil settlement data.

[0014] In the above-mentioned multi-point displacement measurement device applicable to soft soil strata, the top of the left anchor base and the right anchor base are provided with cutting edges. The cutting edges are arc-shaped, and a retaining plate is provided at the narrow groove of the protective pipe. The cutting edges can move through the retaining plate. The width of the narrow groove is the same as that of the cutting edges.

[0015] In the aforementioned multi-point displacement measurement device applicable to soft soil strata, the fulcrum on the left anchoring base is inside the line hole of the right anchoring base, while the fulcrum on the right anchoring base is outside the line hole of the right anchoring base.

[0016] In the above-mentioned multi-point displacement measuring device applicable to soft soil strata, the male connector includes a core and a tenon; the female connector includes an outer hole and an inner hole; the tenon on the male connector is aligned and inserted into the outer hole on the female connector, and then the male connector is rotated counterclockwise to make the tenon slide into the inner hole of the female connector for fixed connection.

[0017] In the aforementioned multi-point displacement measuring device applicable to soft soil strata, the end includes a female connector and a pointed tip; the tenon on the male connector at the lower end of the protective tube is aligned with the outer hole on the female connector at the upper end of the end and inserted into the outer hole, and then rotated counterclockwise to make the tenon slide into the inner hole and fix it.

[0018] In the aforementioned multi-point displacement measuring device applicable to soft soil strata, the male and female connectors are provided with locking grooves, which are elongated groove structures with insertion holes inside; it also includes a locking pin, which is a "C" shaped structure with chamfered ends; the locking pin is inserted into the locking groove and its internal insertion hole for fixation.

[0019] In the aforementioned multi-point displacement measuring device applicable to soft soil strata, the upper end of the male connector is connected to the steel strand, and the male connector includes a male threaded opening and an upper guide cone, with the male threaded opening connected to the upper guide cone; the lower end of the female connector is connected to the steel strand, and the female connector includes a female threaded opening and a lower guide cone, with the female threaded opening rigidly connected to the lower guide cone; the male threaded opening is rotatably connected to the female threaded opening; align the male threaded opening with the female threaded opening, and then rotate the male threaded opening until it is fully connected to its female threaded opening.

[0020] In the aforementioned multi-point displacement measurement device applicable to soft soil layers, the measurement module further includes a solar panel and an antenna. The solar panel is located above the data collector and supplies it with power; the antenna is located to the side of the data collector and transmits data.

[0021] In the aforementioned multi-point displacement measurement device applicable to soft soil strata, the data collector includes a storage unit, an energy storage unit, a signal conversion unit, and a communication transceiver unit, and is powered by a solar panel; the data collector remotely transmits data through the communication transceiver unit, the energy storage unit can store electrical energy to power continuous data acquisition; the signal conversion unit converts the displacement data acquired by the sensor into digital signals for storage and transmission.

[0022] A method for multi-point displacement measurement suitable for soft soil layers, characterized by employing the aforementioned multi-point displacement measurement device suitable for soft soil layers, includes the following steps:

[0023] Step 1: Align the male connector at the lower end of the first section of the protective pipe with the female connector at the upper end and insert them to secure the connection;

[0024] Step 2: Drive the first section of the protective pipe with the end into the soft soil layer using a pile driver, leaving the female connector at the top outside the soil layer. Then, align the male connector at the bottom of the steel strand in the second section of the protective pipe with the female connector at the top of the steel strand in the first section of the protective pipe inserted into the soft soil layer, and tighten the male connector to make the steel strands in the two sections of the protective pipe tightly connected.

[0025] Step 3: Align the male connector of the second section of the protective pipe with the female connector of the first section of the protective pipe that is reserved outside the soft soil layer and insert it to fix the connection. Then use a pile driver to drive the second section of the protective pipe into the soft soil layer.

[0026] Step 4: Repeat steps 2 to 3 until the end reaches the predetermined depth, and let it stand for a period of time to allow the soil structure to recover.

[0027] Step 5: Pull the last section of steel strand inside the protective pipe upwards. The steel strand will cause the cross brace to expand outwards and the cutting edge to penetrate into the soft soil layer.

[0028] Step 6: Align the male connector on the lower steel strand of the measuring module with the female connector on the upper end of the last section of the protective pipe, and tighten the male connector to make the measuring module and the two sections of steel strand inside the protective pipe tightly connected. Finally, align the male connector at the lower end of the measuring module with the female connector at the upper end of the protective pipe and insert them to fix the connection.

[0029] Step 7: Start the measurement module and record settlement data in real time.

[0030] The beneficial effects of this invention are:

[0031] The anchoring head installation technique using steel strands involves pulling the steel strands upwards, causing the anchoring head to move upwards as a whole. However, the anchoring base is ultimately constrained at the upper edge of the narrow groove. As the steel strands continue to pull, they pull the cross brace, causing it to push the fulcrum and the anchoring base to unfold along the slide rail, thus allowing the cutting edge to penetrate into the soil. This achieves the goal of rapid anchoring head installation and features simple device design, convenient installation, and minimal soil disturbance.

[0032] The anchor head is secured by a wire hole and a cross brace locking mechanism. After the anchor head is unfolded, the wire hole end clamps the steel strand, while the cross brace changes from a "V" shape to a "∧" shape to hold the anchor base in place. This achieves a tight connection between the anchor head and the steel strand and locks the anchor base, thus preventing the cutting edge from springing back and simplifying the anchor head structure.

[0033] The technology of using low-deformation steel strands to transmit the settlement of the anchor head achieves the purpose of accurately transmitting the settlement of the anchor head to the grating ruler displacement sensor, which has the effects of high precision, simplified force transmission structure and reduced space occupation.

[0034] The technology of using retaining plates to filter groundwater allows the groundwater to flow into the protective pipe after filtration, which achieves the purpose of preventing mud from entering the protective pipe and maintaining the same water pressure inside and outside. It also has the effect of protecting the steel strands and making it easier for the retaining plates to move together with the anchor head.

[0035] By employing the technology of extending protective pipes and laying protective pipes through piling, the aim of monitoring soft soil layers at different depths and quickly deploying multi-point displacement gauges is achieved. This technology is adaptable to soft soil layers at different depths and avoids hole collapse or debris falling in during the drilling process of deploying multi-point displacement gauges.

[0036] The technology of using high-precision grating ruler sensors to measure displacement enables accurate measurement of settlement in soft soil layers, achieving high precision and automated monitoring.

[0037] Employing fully automated measurement technology, supplemented by solar power and wireless data transmission, it achieves continuous and unmanned monitoring, with the advantages of large data collection volume, high degree of automation, safety and convenience.

[0038] By employing the technology of real-time correction of settlement data using elevation markers, the goal of real-time monitoring and measurement of settlement data is achieved, which has the effect of real-time correction of settlement data to ensure data accuracy. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0040] Figure 2 This is a top view of the structure without anchor heads.

[0041] Figure 3 This is an enlarged schematic diagram of structure A without anchor heads;

[0042] Figure 4 This is a schematic diagram of the BB section structure without anchor heads.

[0043] Figure 5 This is a schematic diagram of the already installed anchor head structure;

[0044] Figure 6 This is an enlarged schematic diagram of the already installed anchor head A structure;

[0045] Figure 7 This is a schematic diagram of the BB section structure of the already installed anchor heads;

[0046] Figure 8 A schematic diagram of the cross-sectional structure of the conduit and steel strand joint;

[0047] Figure 9 This is a top view of the conductor plate structure.

[0048] Figure 10This is a schematic diagram of the cross-sectional structure of a steel strand joint;

[0049] Figure 11 This is a schematic diagram of the cross-sectional structure of the pipe fitting and end;

[0050] Figure 12 A top view schematic diagram of the pipe fitting and end;

[0051] Figure 13 This is a schematic diagram of the locking groove structure;

[0052] Figure 14 This is a top view of the measurement module.

[0053] Figure 15 This is a schematic diagram of the measurement module structure.

[0054] In the diagram: 1—Anchor head; 101—Anchor base; 101-1—Left anchor base; 101-2—Right anchor base; 102—Slide rail; 103—Wire hole; 104—Cutting foot; 105—Soil retaining plate; 106—Steel strand; 107—Horizontal brace; 108—Fusel point; 2—Protective pipe; 201—Male connector; 201-1—Pipe core; 201-2—Tongue; 202—Female connector; 202-1—Outer hole; 202-2—Inner hole; 203—Narrow groove; 204—Guide plate; 204-1—Guide Wire hole; 205—Locking groove; 206—Locking pin; 207—Main wire connector; 207-1—Main threaded opening; 207-2—Upper guide cone; 208—Main wire connector; 208-1—Female threaded opening; 208-2—Lower guide cone; 301—Point; 4—Measuring module; 401—Cylinder; 402—Optical scale displacement sensor; 403—Pulley; 404—Tension spring; 405—Data cable; 406—Data collector; 407—Solar panel; 408—Antenna; 409—Elevation marker. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0056] The present invention relates to a multi-point displacement measurement device suitable for soft soil layers, the structure of which is as follows: Figure 1-15 As shown, it includes an anchor head 1, a protective tube 2, an end head 3, and a measuring module 4; the anchor head 1 is vertically installed inside the hollow protective tube 2, and the protective tube 2 has a male connector 201 and a female connector 202 at both ends, the male connector 201 is connected to the end head 3, and the female connector 202 is connected to the measuring module 4.

[0057] The anchor head 1 includes a strip-shaped anchor base 101, which includes a left anchor base 101-1 and a right anchor base 101-2. Long strip-shaped wire holes 103 are provided on the left anchor base 101-1 and the right anchor base 101-2. A slide rail 102 is provided on the edge of the right anchor base 101-2. The left anchor base 101-1 and the right anchor base 101-2 are stacked on top of each other and slidably connected along the slide rail 102. A steel strand 106 is vertically connected movably within the wire hole 103. Both the left anchor base 101-1 and the right anchor base 101-2 are provided with fulcrums 108, and two fulcrums 108 are connected to a cross brace 107. The other end of the cross brace 107 is connected to the steel strand 106. A narrow groove 203 is provided on the surface of the vertical protective tube 2, through which the anchor head 1 is movably installed.

[0058] There are two or more protective pipes 2, which are connected to each other by male connectors 201 and female connectors 202 at both ends; there are two or more anchor heads 1 vertically arranged inside the protective pipe 2, and a guide plate 204 is arranged parallel between the anchor heads 1, which separates the anchor heads 1; each anchor head 1 is connected to a steel strand 106; the guide plate 204 is provided with two or more guide holes 204-1, through which the steel strand 106 is passed and supported; the two ends of the steel strand 106 are provided with male connectors 207 and female connectors 208, and the steel strands 106 are connected to each other by the male connectors 207 and female connectors 208;

[0059] The measurement module 4 includes a protective sleeve 401 for protecting internal components. The protective sleeve 401 is a cylindrical structure. A grating ruler displacement sensor 402 is fixedly installed inside the protective sleeve 401. One end of the grating ruler displacement sensor 402 is connected to a steel strand 106, and the other end is connected to a tension spring 404. The tension spring 404 pulls the steel strand 106 and keeps it taut. A pulley is also slidably connected to the steel strand 106 connected to the grating ruler displacement sensor 402. A data line 405 is connected to the grating ruler displacement sensor 402. The data line 405 is connected to a data collector 406, which stores the displacement data acquired by the grating ruler displacement sensor 402. An elevation mark 409 is set at the center of the protective sleeve 401.

[0060] After the cutting edge 104 penetrates the soft soil layer, if the soil layer deforms and settles, the anchor head 1 moves downwards, thereby pulling the steel strand 106 and driving the grating ruler displacement sensor 402 in the measurement module 4 to move. The data line 405 transmits the displacement data obtained by the grating ruler displacement sensor 402 to the data collector 406. During the measurement process, the measurement module 4 may settle along with the protective pipe 2. The settlement amount of the measurement module 4 is continuously obtained through the elevation marker 409, and the settlement data is corrected based on this, thereby obtaining the soft soil settlement data.

[0061] Anchor head 1 Figures 1 to 7 As shown, the structure includes an anchoring base 101, a slide rail 102, a wire hole 103, a cutting edge 104, a retaining plate 105, a steel strand 106, a cross brace 107, and a fulcrum 108. The anchoring base 101 includes a left anchoring base 101-1 and a right anchoring base 101-2, both of which have wire holes 103 at the top. The two are connected by the slide rail 102 and can move outward along the slide rail 102. The cutting edge 104 passes through the retaining plate 105 and is initially located within the narrow groove 203 to prevent the protective pipe 2 from being driven in. The cutting edge 2 is frequently damaged in soft soil layers; the retaining plate 105 can prevent soil from entering the casing 2 and affecting the movement of the steel strand 106, and allows groundwater to enter the casing 2 after filtration to balance the external water pressure, making it easier for the retaining plate 105 to move downward with the anchor head 1; the steel strand 106 passes through the wire hole 103 and is connected to the cross brace 107, which is used to lay the anchor head 1 and transmit displacement; one end of the cross brace 107 is connected to the steel strand 106, and the other end is connected to the support point 108; the support point 108 is connected to the anchor base respectively. The left and right parts of 101 are connected. The fulcrum 108 on the left anchoring base 101-1 is located in the wire hole 103 of the right anchoring base 101-2. The cross brace 107 adopts a "V" shaped structure. When the steel strand 106 is pulled upward, the anchor head 1 moves upward as a whole, but is eventually constrained at the upper edge of the narrow groove 203. As the steel strand 106 continues to move upward, the cross brace 107 generates a thrust at the fulcrum 108, causing the fulcrum 108 to move outward and thus push the left anchoring base 101-1 and the right anchor. The anchor body 101-2 opens outward along the slide rail 102, and the cutting edge 104 penetrates into the soft soil layer along the narrow groove 203. The included angle of the cross brace 107 continuously increases, eventually changing from a "V" shape to a "∧" shape to hold the anchor body 101 and prevent it from rebounding. The end of the wire hole 103 clamps the steel strand 106. The two work together to lock the anchor body 101 and prevent the cutting edge 104 from rebounding. At this time, the fulcrum 108 contacts the retaining plate 105, which can prevent the retaining plate 105 from moving inward under the action of soil pressure.

[0062] Protective tube 2 Figures 8 to 13As shown, the system includes a male connector 201, a female connector 202, a narrow slot 203, a conductor plate 204, a locking slot 205, a locking pin 206, a male wire connector 207, and a female wire connector 208. The male connector 201 includes a core 201-1 and a tenon 201-2, while the female connector 202 includes an outer hole 202-1 and an inner hole 202-2. When connecting the protective tube 2, the tenon 201-2 is aligned with the outer hole 202-1, and the connection is completed by rotating the tenon into the inner hole 202-2. Several conductor holes 204-1 on the conductor plate 204 support the steel strands 106, preventing them from interfering with each other and affecting the displacement observation results. This also allows the steel strands 106 to be placed close to the conductor. To reduce space usage; both male connector 201 and female connector 202 have locking grooves 205; after male connector 201 and female connector 202 are connected, locking pin 206 is inserted into locking groove 205 to prevent connection failure; the lower end of steel strand 106 inside the protective tube 2 has a male threaded opening 207-1 and an upper guide cone 207-2, the male threaded opening 207-1 can rotate freely to connect with busbar connector 208; the lower end of busbar connector 208 is connected to steel strand 106 and rigidly connected to lower guide cone 208-2; upper guide cone 207-2 and lower guide cone 208-2 allow male connector 207 and busbar connector 208 to pass smoothly through conductor hole 204-1.

[0063] End 3 Figure 11 As shown, it includes a female connector 202 and a pointed end 301; the female connector 202 allows the end 3 to be connected to the protective pipe 2, and the connection method is the same as that of the protective pipe 2, and the end 3 also has a locking groove 205; the pointed end 301 is made of high-strength alloy steel, which can protect the lower end of the protective pipe 2 and make it easier for the piling machine to drive it into the soft soil layer; the protective pipe 2 with the end 3 connected is driven into the soft soil layer by the piling machine, which can be used for soft soil layers of different depths and avoids the drilling process.

[0064] Measurement module 4, such as Figure 14 , Figure 15As shown, the system includes a protective sleeve 401, a grating ruler displacement sensor 402, a pulley 403, a tension spring 404, a data cable 405, a data collector 406, a solar panel 407, an antenna 408, and an elevation marker 409. The protective sleeve 401 is a cylindrical structure that protects the internal equipment and provides support for its installation. The grating ruler displacement sensor 402 has a resolution of 0.005 mm and is fixed to the protective sleeve 401. One end is connected to a steel strand 106, and the other end is connected to a tension spring 404, enabling automated and accurate measurement of the displacement transmitted from the steel strand 106. The pulley 403 can change the direction of the steel strand 106, allowing the grating ruler displacement sensor 405 to move more precisely. 02 is positioned closer to the steel strand 106, which significantly reduces the size of the measurement module 4; the tension spring 404 keeps the steel strand 106 taut, making the displacement data more accurate; the data cable 405 transmits the displacement data to the data collector 406; the data collector 406 can store and transmit data, enabling automated monitoring and providing power to the measurement module 4; the solar panel 407 is located on top of the data collector 406 and charges it, enabling continuous monitoring; the antenna 408 can transmit displacement data, enabling unmanned monitoring; the elevation marker 409 is located at the center of the casing 401, which can acquire the settlement of the measurement module 4 in real time to correct the settlement data.

[0065] Combination Figures 1 to 15 The multi-point displacement gauge deployment method of the present invention includes the following steps:

[0066] Step 1: Align the tenon 201 on the male connector 201 at the lower end of the first section of the protective tube 2 with the outer hole 202-1 on the female connector 202 at the upper end of the end 3 and insert it. Then rotate counterclockwise to slide the tenon 201-2 into the inner hole 202-2. After it is in place, insert the locking pin 206 into the locking groove 205 to complete the fixation.

[0067] Step 2: Drive the first section of the protective pipe 2 with end 3 into the soft soil layer using a pile driver, leaving the female connector 202 at the top of the protective pipe 2 outside the soil layer. Then, align the male thread 207-1 at the bottom of the steel strand 106 in the second section of the protective pipe 2 with the female thread 208-1 at the top of the steel strand 106 in the first section of the protective pipe 2 inserted into the soft soil layer, and tighten the male thread 207-1 to make the steel strands 106 in the two sections of the protective pipe 2 tightly connected.

[0068] Step 3: Connect the second section of the protective pipe 2 to the first section of the protective pipe 2 that is reserved outside the soft soil layer in the same way as described in Step 1. Then, drive the second section of the protective pipe 2 into the soft soil layer using a pile driver. This method can effectively avoid problems such as borehole collapse or debris falling into the hole during conventional installation.

[0069] Step 4: Repeat steps 2 to 3, freely combining lengths to adapt to different needs; until end 3 reaches the predetermined depth, and leave it for a period of time to allow the soft soil structure to recover, and allow groundwater to flow into the protective pipe 2 after filtration to maintain the balance of internal and external water pressure, so that the retaining plate 105 can be more easily lowered along with the anchor head 1 during the monitoring process.

[0070] Step 5: Pull the last section of the steel strand 106 inside the protective pipe 2 upwards. The steel strand 106 drives the anchor head 1 to move upwards as a whole, and the anchor base 101 is finally constrained at the upper edge of the narrow groove 203. As the steel strand 106 continues to move upwards, it pulls the cross brace 107 and pushes the fulcrum 108 outwards, thereby pushing the left anchor base 101-1 and the right anchor base 101-2 outwards along the slide rail 102, and causing the cutting foot 104 to penetrate into the soft soil layer along the narrow groove 203. After the anchor head 1 is unfolded, the end of the wire hole 103 clamps the steel strand 106, and the cross brace 107 changes from a "V" shape to a "∧" shape to hold the anchor base. The two work together to lock the anchor base 101, completing the installation of the anchor head 1.

[0071] Step 6: Connect the male thread 207-1 on the lower steel strand 106 of the measuring module 4 to the female thread 208-1 on the upper end of the last section of the protective tube 2 in the same way as described in Step 2; then connect the measuring module 4 in the same way as described in Step 1.

[0072] Step 7: Start the measurement module 4 and record settlement data in real time; when the soft soil layer settles, the anchor head 1, which moves downward with the soil, can drive the steel strand 106 to move together, thereby pulling the grating ruler displacement sensor 402 in the measurement module, and converting the displacement data into an electrical signal and storing it in the data collector 406 in the measurement module 4; during the recording process, the settlement data is continuously corrected by measuring the settlement amount through the elevation marker 409.

[0073] This invention relates to a multi-point displacement measurement device and method for soft soil layers. An anchor head is located inside a protective pipe, with an end head at the bottom of the pipe and a measurement module at the top. The end head, measurement module, and the protective pipe, as well as the pipes themselves, are connected using joints. The protective pipe is connected segment by segment and driven into the soft soil layer using a pile driver. The protective pipe contains steel strands, which are also connected using joints and are connected to the anchor head and measurement module. When the anchor head is deployed, the steel strands can be pulled upwards to extend outwards and penetrate the soil. When the soft soil layer settles, the anchor head moves with the soil, causing the steel strands to pull the measurement module. The grating ruler displacement sensor converts displacement data into electrical signals and stores them in the storage module within the measurement module. The device's protective casing, end caps, and measurement module are spliced ​​together, allowing for flexible length combinations to adapt to soft soil layers of varying depths. The anchoring heads are installed by penetrating the soil, effectively reducing soil disturbance. The protective casing is driven into the soft soil layer using a pile driver, effectively preventing borehole collapse and debris ingress during conventional multi-point displacement gauge installation, while significantly saving installation time. This invention can be used to measure settlement at different depths within soft soil, providing real-time ground settlement monitoring data for underground engineering projects.

[0074] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A multi-point displacement measuring device for soft soil layers, characterized in that, It includes an end (3), an anchor head (1) and a measuring module (4) that are fixed together from bottom to top; the anchor head (1) is set inside the hollow protective tube (2); The anchor head (1) includes a strip-shaped anchor base (101), which includes a left anchor base (101-1) and a right anchor base (101-2) with an elongated wire hole (103); the right anchor base (101-2) is provided with a slide rail (102) connecting the left anchor base (101-1) at its edge, and a steel strand (106) is threaded through the wire hole (103); the left anchor base (101-1) and the right anchor base (101-2) are also provided with a slide rail (102) connecting the left anchor base (101-1). Each of the solid bases (101-2) is provided with a support point (108) for connecting the cross brace (107), and the other end of the cross brace (107) is connected to the steel strand (106); the anchor head (1) can move through the narrow groove (203) of the through-tube (2); the conductor plate (204) with conductor hole (204-1) is arranged in parallel between the anchor heads (1), and each steel strand (106) passes through the conductor hole (204-1) to connect to the corresponding anchor head (1); The measurement module (4) includes a protective sleeve (401) for protecting internal components; a grating ruler displacement sensor (402) is fixedly installed inside the protective sleeve (401), and the grating ruler displacement sensor (402) is connected to a steel strand (106); The top of the left anchorage base (101-1) and the right anchorage base (101-2) are provided with cutting edges (104). The cutting edges (104) are arc-shaped and a retaining plate (105) is provided at the narrow groove (203) of the protective pipe (2). The cutting edges (104) can move through the retaining plate (105). The width of the narrow groove (203) is the same as that of the cutting edges (104). The steel strands (106) are interconnected by male connectors (207) and female connectors (208) located at both ends. The upper end of the male connector (207) is connected to the steel strand (106), and the male connector (207) includes a male threaded opening (207-1) and an upper guide cone (207-2), with the male threaded opening (207-1) connected to the upper guide cone (207-2). The lower end of the female connector (208) is connected to the steel strand (106). The busbar connector (208) includes a female threaded port (208-1) and a lower guide cone (208-2). The female threaded port (208-1) and the lower guide cone (208-2) are rigidly connected. The male threaded port (207-1) is rotatably connected to the female threaded port (208-1). Align the male threaded port (207-1) with the female threaded port (208-1), and then rotate the male threaded port (207-1) until it is fully connected to its female threaded port (208-1).

2. The multi-point displacement measuring device for soft soil layers according to claim 1, characterized in that: The fulcrum (108) on the left anchoring base (101-1) is inside the wire hole (103) of the right anchoring base (101-2); the fulcrum (108) on the right anchoring base (101-2) is inside the wire hole (103) of the left anchoring base (101-1).

3. The multi-point displacement measuring device for soft soil layers according to claim 1, characterized in that: The protective tube (2), end (3) and measuring module (4) are interconnected by male connector (201) and female connector (202) provided at both ends or one end; The male connector (201) includes a core (201-1) and a tenon (201-2); the female connector (202) includes an outer hole (202-1) and an inner hole (202-2); the tenon (201-2) on the male connector (201) is aligned and inserted into the outer hole (202-1) on the female connector (202), and then the male connector (201) is rotated counterclockwise to make the tenon (201-2) slide into the inner hole (202-2) of the female connector (202) for fixed connection.

4. The multi-point displacement measuring device for soft soil layers according to claim 3, characterized in that: The end (3) includes a female connector (202) and a pointed end (301); the tenon (201-2) on the male connector (201) at the lower end of the protective tube (2) is aligned with the outer hole (202-1) on the female connector (202) at the upper end of the end (3) and inserted into the outer hole (202-1), and then rotated counterclockwise to make the tenon (201-2) slide into the inner hole (202-2) and be fixed.

5. The multi-point displacement measuring device for soft soil layers according to claim 4, characterized in that: The male connector (201) and the female connector (202) are provided with locking grooves (205), which are elongated groove structures with insertion holes inside the grooves; the connector also includes a locking pin (206), which is a "C" shaped structure with chamfered ends; the locking pin (206) is inserted into the locking groove (205) and the insertion holes inside it for fixing.

6. The multi-point displacement measuring device for soft soil strata according to claim 1, characterized in that: The two ends of the grating ruler displacement sensor (402) are respectively connected to a steel strand (106) and a tension spring (404); the steel strand (106) connected to the grating ruler displacement sensor (402) is also slidably connected to a pulley (403); the grating ruler displacement sensor (402) is connected to a data line (405), the data line (405) is connected to a data collector (406), and the data collector (406) stores the displacement data acquired by the grating ruler displacement sensor (402); an elevation marker (409) is set at the center of the casing (401).

7. The multi-point displacement measuring device for soft soil layers according to claim 6, characterized in that: Soil settlement drags the anchor head (1) to pull the steel strand (106) to move the grating ruler displacement sensor (402). The data line (405) transmits the displacement data obtained by the grating ruler displacement sensor (402) to the data collector (406). The measurement module (4) may settle along with the protective pipe (2) during the measurement process. The settlement amount of the measurement module (4) is continuously obtained through the elevation marker (409), and the settlement data is corrected based on this, and finally the soft soil settlement data is obtained.

8. A method for multi-point displacement measurement in soft soil layers, characterized in that, The multi-point displacement measuring device for soft soil layers according to any one of claims 1 to 7 includes the following steps: Step 1: Align the male connector (201) at the lower end of the first section of the protective pipe (2) with the female connector (202) at the upper end of the end (3) and insert them for fixed connection; Step 2: Drive the first section of the protective pipe (2) with end (3) into the soft soil layer using a pile driver, leaving the female connector (202) at the top outside the soil layer. Then, align the male connector (207) at the bottom of the steel strand (106) in the second section of the protective pipe (2) with the female connector (208) at the top of the steel strand (106) in the first section of the protective pipe (2) inserted into the soft soil layer, and tighten the male connector (207) to make the steel strand (106) in the two sections of the protective pipe (2) tightly connected. Step 3: Align the male connector (201) of the second section of the protective pipe (2) with the female connector (202) of the first section of the protective pipe (2) reserved outside the soft soil layer and insert them for fixed connection. Then use a pile driver to drive the second section of the protective pipe (2) into the soft soil layer. Step 4: Repeat steps 2 to 3 until the end (3) reaches the predetermined depth, and leave it for a period of time to allow the soil structure to recover; Step 5: Pull the last section of the protective pipe (2) upwards, the steel strand (106) inside the pipe will cause the cross brace (107) to spread outwards and the cutting edge (104) to penetrate into the soft soil layer; Step 6: Align the male connector (207) on the lower steel strand (106) of the measuring module (4) with the bus connector (208) at the upper end of the last section of the protective tube (2), and tighten the male connector (207) to make the two sections of steel strand (106) in the measuring module (4) and the protective tube (2) tightly connected. Finally, align the male connector (201) at the lower end of the measuring module (4) and the female connector (202) at the upper end of the protective tube (2) and insert them for fixed connection. Step 7: Start the measurement module (4) and record the settlement data in real time.

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