Marine environment under the calcareous sand grouting diffusion reinforcement simulation device and experimental method

Abstract

The application discloses a kind of calcareous sand grouting diffusion reinforcement simulation device and experimental method under seawater environment, belong to island and reef engineering geological disaster prevention field.It includes: seawater environment simulation system, calcareous sand layer simulation system, data acquisition and monitoring system, grouting and slurry storage system;Seawater environment simulation system forms seepage circuit;Calcareous sand layer simulation system is arranged in seawater environment simulation system, and two ends are connected with two groups of grouting pipe and a group of exhaust port;Data acquisition and detection system includes pressure sensor buried in different positions of calcareous sand layer, sensor is connected with signal collector, and is fed back to computer control platform by signal collector;Grouting and slurry storage system inputs slurry from slurry storage barrel into calcareous sand layer simulation system.By first water tank, second water tank and flow rate control mechanism, the inflow and flow rate of seawater and the formation of seepage circuit can be controlled, the real seawater environment can be accurately simulated and restored, and the grouting test simulation research can be conveniently carried out indoors.

Description

Technical Field

[0001] This invention relates to a simulation device and experimental method for grouting diffusion reinforcement of calcareous sand in a seawater environment, belonging to the field of geological disaster prevention and control technology for island and reef engineering. Background Technology

[0002] Calcareous sand layers are characterized by abundant porosity, weak cementation, easily broken particles, low strength, high permeability, and high compressibility. These characteristics lead to more destructive geological hazards such as foundation voids, foundation subsidence, foundation settlement deformation, large structural deformation, overall structural instability, and soil liquefaction. These are key and unavoidable challenges during the construction and operation phases of island and reef engineering projects. Although grouting theory and technology have been widely applied in geotechnical engineering, research on calcareous sand grouting, both domestically and internationally, is still lacking. In particular, the grout diffusion pattern in calcareous sand grouting is difficult to determine, and the grouting reinforcement effect cannot be reasonably evaluated and predicted. Existing grouting theories are difficult to apply directly. Grouting diffusion reinforcement experimental methods can comprehensively and realistically simulate the grouting conditions of island and reef geological structures under seawater conditions, providing a basis for establishing new theories and mathematical models, and are an important research tool.

[0003] The existing calcareous sand grouting diffusion model test system has the following problems: 1. The existing calcareous sand grouting diffusion model test device fails to simulate grouting diffusion reinforcement in a seawater environment, and the experimental data obtained differs greatly from the actual situation; 2. The existing calcareous sand grouting diffusion model test device is designed for single-hole single-sequence grouting and cannot achieve multi-hole multi-sequence grouting; 3. The existing calcareous sand grouting diffusion model test device is complex, the experimental process is cumbersome, the experimental error is large, and it is easy to waste materials and cause unnecessary losses. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned shortcomings of the prior art and provide a simulation device and experimental method for grouting diffusion reinforcement of calcareous sand in a seawater environment; it can simulate the grouting diffusion reinforcement process of calcareous sand in a seawater environment in a relatively realistic way, realize the visualization of the grouting diffusion process, and realize multi-hole and multi-sequence grouting of calcareous sand layers.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment includes a seawater environment simulation system, a calcareous sand layer simulation system, a data acquisition and monitoring system, and a grouting and storage system.

[0007] The seawater environment simulation system includes:

[0008] First water storage tank;

[0009] The inlet of the first transparent container is connected to the outlet of the first water storage tank;

[0010] A flow rate control mechanism is installed at the inlet of the first transparent container;

[0011] The inlet of the second water storage tank is connected to the outlet of the first transparent container;

[0012] The water pump pumps water from the first water storage tank into the first transparent container.

[0013] The calcareous sand layer simulation system includes a second transparent container; the second transparent container is disposed inside the first transparent container and is statically connected to the first transparent container; the second transparent container has a grouting port at its upper end and an air vent at its lower end, and several water-permeable holes are opened on its side wall; the second transparent container is filled with calcareous sand to form a calcareous sand layer;

[0014] The data acquisition and monitoring system includes:

[0015] Several pressure sensors are embedded in different locations within the calcareous sand layer;

[0016] A signal collector is connected to the pressure sensor signal;

[0017] A computer control platform is connected to the signal collector.

[0018] The grouting and grout storage system includes:

[0019] A slurry storage tank, the slurry outlet of which is connected to the slurry injection port of the second transparent container;

[0020] An air compressor, the outlet of which is connected to the inside of the slurry storage tank, injects the slurry from the storage tank into the second transparent container.

[0021] According to some embodiments disclosed in this invention, the calcareous sand layer simulation system may further include a fixing device; the second transparent container and the first transparent container are connected by the fixing device.

[0022] According to some embodiments disclosed in this invention, the fixing device includes a top plate, a bottom plate, and a connector, the connector being connected between the bottom plate and the top plate; at least one edge of the top plate is connected to the inner wall of the first transparent container, and at least one edge of the bottom plate is connected to the inner wall of the first transparent container; the second transparent container is located between the bottom plate and the top plate and is statically connected to the bottom plate.

[0023] According to some embodiments disclosed in this invention, the flow rate control mechanism includes:

[0024] cavity;

[0025] A partition mechanism, disposed within the cavity, divides the internal space of the cavity into an upper space and a lower space.

[0026] The channel mechanism is vertically arranged in the lower space, dividing the lower space into a left space and a right space. Its top end is open and communicates with the upper space, and its bottom end is connected to the cavity. Several water-permeable holes are opened on the side wall of the channel mechanism.

[0027] A gate is installed within the channel mechanism, its edge is sealed to the inner wall of the channel mechanism, and it moves up and down along the channel mechanism.

[0028] A telescopic connecting mechanism, which extends vertically, is installed inside the cavity, with one end connected to the top of the cavity and the other end connected to the top of the gate.

[0029] The inlet of the flow rate control mechanism is located in the left space, and the outlet of the flow rate control mechanism is located in the right space.

[0030] According to some embodiments disclosed in this invention, the telescopic connection mechanism includes:

[0031] A telescopic rod is installed in the upper space, extends and retracts vertically, and its top end is connected to the top of the cavity;

[0032] A connecting rod is installed horizontally in the upper space, with one end connected to the telescopic end of the telescopic rod and the other end connected to the gate.

[0033] A fixed rod is installed in the upper space, with one end connected to the lower end of the telescopic rod and the other end connected to the top of the partition mechanism.

[0034] According to some embodiments disclosed in this invention, the flow rate control mechanism is disposed inside the first transparent container, and its inlet is connected to the inlet of the first transparent container.

[0035] According to some embodiments disclosed in this invention, a seawater salinity detector is also included; the detection head of the seawater salinity detector is located inside the first water storage tank.

[0036] According to some embodiments disclosed in this invention, a flow meter, a pressure gauge, and a switching valve are also included; the flow meter and the switching valve are respectively disposed between the outlet of the first water storage tank and the inlet of the first transparent container, and between the outlet of the first transparent container and the inlet of the second water storage tank; the pressure gauge is disposed between the slurry storage tank and the slurry injection port of the second transparent container.

[0037] According to some embodiments disclosed in this invention, the grouting and grout storage system includes a stirring mechanism; the stirring mechanism is disposed inside the grout storage tank.

[0038] The experimental method of the above-mentioned calcareous sand grouting diffusion reinforcement simulation device in a seawater environment was adopted.

[0039] Step 1: Prepare calcareous sand and seawater with the same or similar properties based on the calcareous sand layer being studied and its actual environment;

[0040] Step 2: Seawater is poured into the first storage tank, and calcareous sand is filled into the second transparent container to form a calcareous sand layer. Pressure sensors are buried at different locations inside the calcareous sand layer.

[0041] Step 3: Debug the seawater environment simulation system and the grouting and storage system to make them meet the required experimental conditions, and ensure the stability of the experimental data acquisition and the smoothness of the experimental process;

[0042] Step 4: After the grouting and storage system and the seawater environment simulation system have reached the design values, the seawater environment simulation system is turned on to inject seawater into the first transparent container, and the grouting and storage system is turned on to inject grout into the sand layer simulation system. The seawater environment is formed through the water-permeable holes of the second transparent container in the sand layer simulation system, and the grouting diffusion test is carried out.

[0043] During the grouting diffusion test, the data output from the pressure sensor in the second transparent container to the signal collector is recorded at any time. At the same time, the camera is turned on to record the whole process and record the raw data of the flow meter, pressure gauge and other instruments on the water injection pipe and grouting pipe in a timely manner.

[0044] Step 5: After the grouting diffusion test, the experimental soil in the sand layer simulation system can be removed to test the grout diffusion radius;

[0045] Step 6: After measuring the grout diffusion radius, the experimental soil is cured for 2 days to form reinforced soil. The model is removed and the core is taken out to obtain the standard specimen of the uniaxial compressive strength of the reinforced body. Then, geotechnical tests are carried out on the standard specimen of the uniaxial compressive strength of the reinforced body to determine the relevant strength of the reinforced body.

[0046] The beneficial effects achieved by this invention compared with the prior art are as follows:

[0047] 1. The calcareous sand grouting diffusion reinforcement simulation device provided by the present invention can control the entry and exit of seawater and the flow rate and form a seepage loop through the first water tank, the second water tank and the flow rate control mechanism. It can accurately simulate and restore the real seawater environment and facilitate grouting test simulation research in the room.

[0048] 2. The calcareous sand grouting diffusion reinforcement simulation device provided by the present invention, through a transparent container and fixing device, can not only overcome the traditional single-hole single-sequence grouting method, thereby accurately realizing the multi-hole multi-sequence grouting scheme commonly used in actual engineering, but also make the entire device more robust and compact, and increase the accuracy of experimental data.

[0049] 3. The calcareous sand grouting diffusion reinforcement simulation device provided by the present invention adopts a transparent, visual, and corrosion-resistant design for the seawater storage container in the seawater environment simulation system and the sand holding system in the calcareous sand layer simulation system. The video recorder used can record the injection and diffusion of grout anytime and anywhere, solving the problem that traditional injectable equipment cannot be observed in real time and intuitively.

[0050] 4. The calcareous sand grouting diffusion reinforcement simulation device in the seawater environment provided by the present invention has a stirring mechanism installed in the grout storage tank of the grouting and storage system, which can stir the grout at any time to make its concentration uniform and prevent the grout from segregating due to prolonged storage time. Attached Figure Description

[0051] Figure 1 This is a schematic diagram of a calcareous sand grouting diffusion reinforcement simulation device in a seawater environment, as disclosed in an embodiment of the present invention.

[0052] Figure 2 This is a top view of the second transparent container provided in an embodiment of the present invention;

[0053] Figure 3 A front view schematic diagram of the stirring mechanism provided in an embodiment of the present invention;

[0054] Figure 4 A cross-sectional schematic diagram of the flow rate control mechanism provided in an embodiment of the present invention;

[0055] In the diagram: 1. Computer control platform; 2. Signal collector; 3. Exhaust pipe; 4. Calcareous sand layer; 5. Second transparent container; 5-110. First grouting port; 5-111. Second grouting port; 6. First transparent container; 7. Pressure sensor; 8. First permeable hole; 9. Filter layer; 12. Flow rate control mechanism; 12-1. Telescopic rod; 12-2. Connecting rod; 12-3. Fixing rod; 12-4. Second permeable hole; 12-5. Gate; 13. First grouting pipe; 14. Second grouting pipe; 15. Second pressure gauge; 16. Second flow meter; 17. Second switching valve; 15- 1. First pressure gauge; 16-1. First flow meter; 17-1. First switching valve; 18. Drain pipe flow meter; 19. Drain pipe switching valve; 20. Agitator; 20-1. Agitator engine; 20-2. Agitator rod; 20-3. Agitator wheel; 21. Slurry storage tank; 22. Second water storage tank; 23. Camera; 24. Air pipe; 25. Air pipe switching valve; 26. Air compressor; 27. Water injection pipe switching valve; 28. Water injection pipe flow meter; 29. ​​Water injection pipe; 30. First water storage tank; 31. Water injection pump; 32. Seawater salinity detector; 33. Baffle plate; 34. Drain pipe. Implementation

[0056] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0057] The structures, proportions, and sizes illustrated in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the invention. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, provided they do not affect the effectiveness or purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0058] like Figure 1-4 As shown, a simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment is mainly composed of four parts: a seawater environment simulation system, a calcareous sand layer simulation system, a data acquisition and monitoring system, and a grouting and storage system.

[0059] The seawater environment simulation system includes a first water storage tank 30, a first transparent container 6, a flow rate control mechanism 12, a second water storage tank 22, and a water injection pump 31. The first transparent container 6 can be made of a corrosion-resistant, transparent organic material; for example, it can be made of transparent glass and coated with an anti-corrosion coating.

[0060] The outlet of the first water tank 30 is connected to the inlet of the first transparent container 6, and the outlet of the first transparent container 6 is connected to the inlet of the second water tank 22. The first water tank 30 contains seawater, which flows out of the first water tank 30, through the first transparent container 6, and into the second water tank 22, forming a seepage loop to simulate a seawater environment. The first water tank 30, the first transparent container 6, and the second water tank 22 can be connected by water pipes. Specifically, the outlet of the first water tank 30 is connected to the inlet of the first transparent container 6 through a water injection pipe 29, and the outlet of the first transparent container 6 is connected to the inlet of the second water tank 22 through a drain pipe 34. Furthermore, a water injection pipe flow meter 28 and a water injection pipe switch valve 27 can be installed on the water injection pipe 29, and a drain pipe flow meter 18 and a drain pipe switch valve 19 can be installed on the drain pipe 34.

[0061] Water injection pumps 31 are installed at various points in the first water storage tank 30. The water injection pumps 31 output pressure to allow seawater in the first water storage tank 30 to flow into the first transparent container 6. Specifically, the water injection pumps 31 are located inside the first water storage tank 30, at the top. For example, a perforated partition can be installed at the top of the first water storage tank 30 to house the water injection pumps 31. A seawater salinity detector 32 can also be installed in the first water storage tank 30; the detection head of the seawater salinity detector 32 is located inside the first water storage tank 30.

[0062] A flow rate control mechanism 12 is installed at the inlet of the first transparent container 6, and the inlet of the flow rate control mechanism 12 is connected to the inlet of the first transparent container 6; it is used to adjust the flow rate of seawater entering the first transparent container 6. The flow rate control mechanism 12 can be any existing flow rate controller capable of adjusting the water flow rate. Specifically, the flow rate control mechanism 12 can be such as… Figure 4 The structure shown.

[0063] like Figure 4 The flow rate control mechanism 12 shown includes: a cavity, a separating mechanism, a channel mechanism, a gate 12-5, and a telescopic connecting mechanism; wherein, the separating mechanism, the channel mechanism, the gate 12-5, and the telescopic connecting mechanism are all disposed in the cavity.

[0064] The partition mechanism divides the internal space of the cavity into an upper space and a lower space. Specifically, the partition mechanism can be a plate-like structure with the same shape as the horizontal cross-section of the cavity. The partition mechanism has an opening that connects the upper space and the lower space.

[0065] The channel mechanism is vertically positioned within the lower space, dividing it into a left space and a right space. The top of the channel mechanism is open, communicating with the lower space through the opening of the dividing mechanism. The top edge of the channel mechanism is sealed to the bottom surface of the dividing mechanism. The bottom end of the channel mechanism is sealed to the bottom surface of the cavity. Several second permeable holes 12-4 are provided on the sidewalls of the channel mechanism; the left and right spaces in the lower part of the cavity can only be connected through these second permeable holes 12-4 on the sidewalls of the channel mechanism. The inlet of the flow rate control mechanism 12 is located in the left space, and the outlet of the flow rate control mechanism 12 is located in the right space; water enters the left space, flows through the channel mechanism, and exits from the right space. The second permeable holes 12-4 on the sidewalls of the channel mechanism can be arranged regularly or symmetrically.

[0066] Gate 12-5 is installed within the channel mechanism, its edges sealing against the inner wall of the channel mechanism. Gate 12-5 moves up and down along the channel mechanism. Specifically, gate 12-5 can be divided into a vertical part and a horizontal part; the horizontal part is horizontally installed within the channel mechanism, its edges sealing against the inner wall of the channel mechanism, while the vertical part is vertically installed within the channel mechanism, its lower end connecting to the upper surface of the horizontal part, and its upper end connecting to the telescopic connecting mechanism. The side edges of the vertical part are sealed against the inner wall of the channel mechanism. Gate 12-5 divides several second permeable holes 12-4 on the side wall of the channel mechanism into left and right parts. The second permeable hole 12-4 on the left side is the inlet hole, and the second permeable hole 12-4 on the right side is the outlet hole. Water enters the channel mechanism through the second permeable hole 12-4 on the left and is blocked by the gate 12-5. Adjusting the height of the gate 12-5 causes it to move upwards, allowing water in the channel mechanism to pass below it and then flow out through the second permeable hole 12-4 on the right, located below the gate 12-5. Adjusting the height of the gate 12-5 allows for the adjustment of the number of second permeable holes 12-4 that can allow water to enter and exit, thereby controlling the water flow rate.

[0067] The telescopic connecting mechanism, which extends vertically, is installed within the cavity, located in the upper space of the cavity. One end of the telescopic connecting mechanism is connected to the top of the cavity, and the other end is connected to the top of the gate 12-5. Alternatively, the other end of the telescopic connecting mechanism can be connected to the upper part of the vertical section of the gate 12-5. Its function is to adjust the height of the gate 12-5.

[0068] One specific structure of the telescopic connection mechanism can be as follows: Figure 4As shown, it includes a telescopic rod 12-1, a connecting rod 12-2, and a fixing rod 12-3; the telescopic rod 12-1 is set in the upper space and extends vertically, with its top end connected to the top of the cavity; the connecting rod 12-2 is set in the upper space and is horizontally set, with one end connected to the telescopic end of the telescopic rod 12-1 and the other end connected to the gate 12-5; the fixing rod 12-3 is set in the upper space, with one end connected to the lower end of the telescopic rod 12-1 and the other end connected to the top of the separating mechanism.

[0069] The calcareous sand layer simulation system includes a second transparent container 5; the second transparent container 5 is disposed inside and statically connected to the first transparent container 6; the second transparent container 5 has a grouting port at its upper end and an air vent at its lower end, and several first permeable holes 8 are formed on its side wall; the second transparent container 5 is filled with calcareous sand to form a calcareous sand layer 4. The second transparent container 5 can have two or more grouting ports, for example, such as... Figure 1 The two shown are the first grouting port 5-110 and the second grouting port 5-111, respectively. The vent can be connected to the vent pipe 3. Several first water-permeable holes 8 are provided on the side wall of the second transparent container 5, which can be arranged in a regular pattern. The second transparent container 5 can be made of a corrosion-resistant, transparent organic material; for example, transparent glass material coated with an anti-corrosion coating.

[0070] Inside the second transparent container 5 and above the calcareous sand layer 4, a filter layer 9 can also be provided to allow the slurry to penetrate evenly into the calcareous sand layer. The filter layer 9 is made of coarse gauze.

[0071] To further improve the stability of the second transparent container 5, the calcareous sand layer simulation system may also include a fixing device; the second transparent container 5 and the first transparent container 6 are statically connected by the fixing device. Specifically, the fixing device includes a top plate, a bottom plate, and a connector, with the connector connecting the bottom plate and the top plate; at least one edge of the top plate is connected to the inner wall of the first transparent container 6, and at least one edge of the bottom plate is connected to the inner wall of the first transparent container 6; the second transparent container 5 is located between the bottom plate and the top plate and is statically connected to the bottom plate.

[0072] The data acquisition and monitoring system includes: several pressure sensors 7, a signal collector 2, and a computer control platform 1; the pressure sensors 7 are buried at different locations within the calcareous sand layer 4; the signal collector 2 is connected to the pressure sensors 7; and the computer control platform 1 is connected to the signal collector 2. The pressure sensors 7, buried in the calcareous sand layer, are used to collect experimental data generated during the experiment; the signal collector 2 receives the data from the pressure sensors 7 via wires and transmits it to the computer control platform 1.

[0073] The data acquisition and monitoring system may further include a camera 23. The camera 23 is used to film and record the experimental process.

[0074] The grouting and storage system includes a grout storage tank 21 and an air compressor 26. The outlet of the grout storage tank 21 is connected to the grouting port of the second transparent container 5. The outlet of the air compressor 26 is connected to the interior of the grout storage tank 21, injecting the grout from the storage tank 21 into the second transparent container 5; that is, the air compressor 26 injects the grout from the storage tank 21 into the calcareous sand layer simulation system through the grouting pipe. The storage tank 21 and the second transparent container 5 are connected by the grouting pipe. A flow meter, pressure gauge, and on / off valves can be installed on the grouting pipe.

[0075] To prevent segregation of the slurry stored in the storage tank 21 due to prolonged storage time, the grouting and storage system may also include a stirring mechanism 20. The stirring mechanism 20 is located inside the storage tank 21. The stirring mechanism 20 includes a stirring wheel 20-3, a stirring rod 20-2, and a driver for driving the stirring rod 20-2; the stirring wheel 20-3 is located on the stirring rod 20-2, and the driver is located on top of the stirring rod 20-2. The driver may be a stirring motor 20-1. Example

[0076] like Figure 1 As shown, a simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment mainly consists of four parts: a seawater environment simulation system, a calcareous sand layer simulation system, a data acquisition and monitoring system, and a grouting and storage system.

[0077] like Figure 1 As shown, the seawater environment simulation system includes a water injection pump 31, a seawater salinity detector 32, a first water storage tank 30, a flow rate control mechanism 12, a first transparent container 6, and a second water storage tank 22. The first water storage tank 30 is equipped with a perforated baffle 33 to separate the water injection pump 31 from the seawater salinity detector 32. The first water storage tank 30 is connected to the flow rate control mechanism 12 via a water injection pipe 29. The first transparent container 6 is connected to the second water storage tank 22 via a drain pipe 34. The water injection pump 31 outputs pressure to draw seawater into the system through the water injection pipe 29, which then flows sequentially through the flow rate control mechanism 12 and the first transparent container 6, and exits through the drain pipe 34 into the second water storage tank 22, forming a seepage loop.

[0078] like Figure 4 As shown. The flow rate control mechanism 12 includes a telescopic rod 12-1, a connecting rod 12-2, a fixing rod 12-3, a second water-permeable hole 12-4, and a gate 12-5. Seawater enters the flow rate control mechanism 12 through the water injection pipe 29. According to the experimental requirements, the gate 12-5 is raised to the corresponding height, and the seawater flows into the first transparent container 6 through the outlet of the flow rate control mechanism 12, thereby controlling the seawater flow rate. The diameter of the gate 12-5 is the same as the length of the gap.

[0079] like Figure 1As shown, the calcareous sand layer simulation system includes a second transparent container 5 and a fixing device. The second transparent container 5 has grouting ports at its upper and lower parts, and vent ports at its lower part. First permeable holes 8 are formed on the four side walls of the second transparent container 5. The fixing device includes a top plate and a bottom plate, connected by four connectors. One end of each connector passes through the bottom plate and connects to a fixing nut on the bottom plate, while the other end passes through the top plate and connects to a fixing nut on the top plate. The fixing nuts tighten the top and bottom plates. The fixing device is made of corrosion-resistant steel.

[0080] like Figure 1 As shown. The data acquisition and monitoring system includes a pressure sensor 7, a signal collector 2, a computer control platform 1, and a camera 23. The pressure sensor 7 is buried in the calcareous sand layer to collect experimental data generated during the experiment; the signal collector 2 receives the data from the pressure sensor 7 through wires and sends it to the computer control platform 1; the camera 23 is used to film and record the experimental process.

[0081] like Figure 1 As shown. The grouting and storage system includes an air compressor 26, a grout storage tank 21, a first flow meter 16-1, a first pressure gauge 15-1, a first switching valve 17-1, a second flow meter 16, a second pressure gauge 15, a second switching valve 17, and an air pipe switching valve 25. The grout storage tank 21 is connected to the second transparent container 5 through a first grouting pipe 13 and a second grouting pipe 14. The grout storage tank 21 is connected to the air compressor 26 through an air pipe 24. The air compressor 26 outputs pressure to make the grout flow out from the outlet of the grout storage tank 21, pass sequentially through the first flow meter 16-1, the first pressure gauge 15-1, the first switching valve 17-1, the second flow meter 16, the second pressure gauge 15, and the second switching valve 17, and flow into the calcareous sand layer simulation system from the grouting port at the top of the second transparent container 5.

[0082] like Figure 1 As shown. The upper part of the second transparent container 5 has a grouting port, which is connected to the first grouting pipe 13 and the second grouting pipe 14 respectively. The grouting pipes are equipped with a first switch valve 17-1 and a second switch valve 17 respectively, which can be used to carry out multi-hole multi-sequence grouting experiments, providing theoretical guidance for practical engineering.

[0083] like Figure 1 As shown. The upper part of the second transparent container 5 is provided with a filter layer 9, which allows the slurry to penetrate evenly into the sand layer. The filter layer 9 is made of coarse gauze of a special material.

[0084] To facilitate direct observation and recording of the experimental process, both the first transparent container 6 and the second transparent container 5 are made of transparent glass and coated with anti-corrosion paint.

[0085] To prevent segregation of the slurry stored in the storage tank 21 due to prolonged storage, the storage tank 21 is equipped with a stirring mechanism 20. For example... Figure 3 As shown, the stirring mechanism 20 includes a stirring engine 20-1, a stirring rod 20-2, and a stirring wheel 20-3, which can stir the slurry at any time to make its concentration uniform.

[0086] The experimental method of the calcareous sand grouting diffusion reinforcement simulation device in a seawater environment disclosed in the above embodiments was adopted.

[0087] Step 1: Prepare calcareous sand and seawater with the same or similar properties based on the calcareous sand layer being studied and its actual environment;

[0088] Step 2: Inject seawater into the first storage tank, fill the second transparent container 5 with calcareous sand to form a calcareous sand layer 4, and bury the pressure sensor 7 at different locations inside the calcareous sand layer 4.

[0089] Step 3: Debug the seawater environment simulation system and the grouting and storage system to make them meet the required experimental conditions, and ensure the stability of the experimental data acquisition and the smoothness of the experimental process;

[0090] Step 4: After the grouting and storage system and the seawater environment simulation system have reached the design values, the seawater environment simulation system is turned on to inject seawater into the first transparent container 6, and the grouting and storage system is turned on to inject grout into the sand layer simulation system. The seawater environment is formed through the first water-permeable hole 8 of the second transparent container 5 in the sand layer simulation system, and the grouting diffusion test is carried out.

[0091] During the grouting diffusion test, the data output from the pressure sensor 7 in the second transparent container 5 to the signal collector 2 is recorded at any time. At the same time, the camera 23 is turned on to record the whole process and record the original data such as the flow meter and pressure gauge on the water injection pipe 29 and the grouting pipe in a timely manner.

[0092] Step 5: After the grouting diffusion test, the experimental soil in the sand layer simulation system can be removed to test the grout diffusion radius;

[0093] Step 6: After measuring the grout diffusion radius, the experimental soil is cured for 2 days to form reinforced soil. The model is removed and the core is taken out to obtain the standard specimen of the uniaxial compressive strength of the reinforced body. Then, geotechnical tests are carried out on the standard specimen of the uniaxial compressive strength of the reinforced body to determine the relevant strength of the reinforced body.

[0094] Step two may also include the following operations: arranging a pressure sensor 7 and sensing wires inside the second transparent container 5, filling the second transparent container 5 with calcareous sand; tightening the pressure rod connecting the bottom plate and the top plate with the fixing nut to ensure the stability of the second transparent container 5.

[0095] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment, characterized in that, This includes a seawater environment simulation system, a calcareous sand layer simulation system, a data acquisition and monitoring system, and a grouting and slurry storage system; The seawater environment simulation system includes: First water storage tank; The inlet of the first transparent container is connected to the outlet of the first water storage tank; A flow rate control mechanism is installed at the inlet of the first transparent container; The flow rate control mechanism includes: cavity; A partition mechanism, disposed within the cavity, divides the internal space of the cavity into an upper space and a lower space. The channel mechanism is vertically arranged in the lower space, dividing the lower space into a left space and a right space. Its top end is open and communicates with the upper space, and its bottom end is connected to the cavity. Several water-permeable holes are opened on the side wall of the channel mechanism. A gate is installed within the channel mechanism, its edge is sealed to the inner wall of the channel mechanism, and it moves up and down along the channel mechanism. A telescopic connecting mechanism, which extends vertically, is installed inside the cavity. One end of the telescopic connecting mechanism is connected to the top of the cavity, and the other end is connected to the top of the gate. The telescopic connection mechanism includes: A telescopic rod is installed in the upper space, extends and retracts vertically, and its top end is connected to the top of the cavity; A connecting rod is installed horizontally in the upper space, with one end connected to the telescopic end of the telescopic rod and the other end connected to the gate. A fixed rod is installed in the upper space, with one end connected to the lower end of the telescopic rod and the other end connected to the top of the partition mechanism. The inlet of the flow rate control mechanism is located in the left space, and the outlet of the flow rate control mechanism is located in the right space; the inlet of the second water storage tank is connected to the outlet of the first transparent container. The water pump pumps water from the first water storage tank into the first transparent container. The calcareous sand layer simulation system includes a second transparent container; the second transparent container is disposed inside the first transparent container and is statically connected to the first transparent container; the second transparent container has a grouting port at its upper end and an air vent at its lower end, and several water-permeable holes are opened on its side wall; the second transparent container is filled with calcareous sand to form a calcareous sand layer; The data acquisition and monitoring system includes: Several pressure sensors are embedded in different locations within the calcareous sand layer; A signal collector is connected to the pressure sensor signal; A computer control platform is connected to the signal collector. The grouting and grout storage system includes: A slurry storage tank, the slurry outlet of which is connected to the slurry injection port of the second transparent container; An air compressor, the outlet of which is connected to the inside of the slurry storage tank, injects the slurry from the storage tank into the second transparent container.

2. The simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment according to claim 1, characterized in that, The calcareous sand layer simulation system also includes a fixing device; the second transparent container and the first transparent container are connected by the fixing device.

3. The simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment according to claim 2, characterized in that, The fixing device includes a top plate, a bottom plate, and a connector, the connector being connected between the bottom plate and the top plate; at least one edge of the top plate is connected to the inner wall of the first transparent container, and at least one edge of the bottom plate is connected to the inner wall of the first transparent container; the second transparent container is located between the bottom plate and the top plate and is statically connected to the bottom plate.

4. The simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment according to claim 1, characterized in that, The flow rate control mechanism is installed inside the first transparent container, and its inlet is connected to the inlet of the first transparent container.

5. The simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment according to claim 1, characterized in that, It also includes a seawater salinity detector; the detection head of the seawater salinity detector is located inside the first water storage tank.

6. The simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment according to claim 1, characterized in that, It also includes a flow meter, a pressure gauge, and a switching valve; the flow meter and the switching valve are respectively located between the outlet of the first water storage tank and the inlet of the first transparent container, and between the outlet of the first transparent container and the inlet of the second water storage tank, and the pressure gauge is located between the slurry storage tank and the slurry injection port of the second transparent container.

7. The simulation device for grouting diffusion reinforcement of calcareous sand in a seawater environment according to claim 1, characterized in that, The grouting and storage system includes a stirring mechanism; the stirring mechanism is located inside the grout storage tank.

8. The experimental method using the calcareous sand grouting diffusion reinforcement simulation device in a seawater environment as described in any one of claims 1-7, characterized in that, Step 1: Prepare calcareous sand and seawater with the same or similar properties based on the calcareous sand layer being studied and its actual environment; Step 2: Seawater is poured into the first storage tank, and calcareous sand is filled into the second transparent container to form a calcareous sand layer. Pressure sensors are buried at different locations inside the calcareous sand layer. Step 3: Debug the seawater environment simulation system and the grouting and storage system to make them meet the required experimental conditions, and ensure the stability of the experimental data acquisition and the smoothness of the experimental process; Step 4: After the grouting and storage system and the seawater environment simulation system have reached the design values, the seawater environment simulation system is turned on to inject seawater into the first transparent container, and the grouting and storage system is turned on to inject grout into the sand layer simulation system. The seawater environment is formed through the water-permeable holes of the second transparent container in the sand layer simulation system, and the grouting diffusion test is carried out. During the grouting diffusion test, the data output from the pressure sensor in the second transparent container to the signal collector is recorded at any time. At the same time, the camera is turned on to record the whole process and the original data of the flow meter and pressure gauge on the water injection pipe and the grouting pipe are recorded in a timely manner. Step 5: After the grouting diffusion test, the experimental soil in the sand layer simulation system is removed to test the grout diffusion radius; Step 6: After measuring the grout diffusion radius, the experimental soil is cured for 2 days to form reinforced soil. The model is removed and the core is taken out to obtain the standard specimen of the uniaxial compressive strength of the reinforced body. Then, geotechnical tests are carried out on the standard specimen of the uniaxial compressive strength of the reinforced body to determine the relevant strength of the reinforced body.

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