Model test equipment and usage method for simulating the establishment of tunnel jet grouting piles

Abstract

The present invention discloses a model test device for simulating the construction of tunnel jet grouting piles, comprising: a box, a sensor, a pressure regulating device, and a jet grouting device. A soil model is provided in the box, and the soil model is formed with a simulated tunnel lining; the sensor is provided in the soil model and is suitable for monitoring the pressure around the simulated tunnel lining; the pressure regulating device is provided in the box, and is suitable for adjusting the pressure applied to the soil model; the jet grouting device is formed with a drill bit suitable for jet grouting the soil model, and the jet grouting device is movably provided in the box to selectively perform jet grouting on the soil model around the simulated tunnel lining. The present invention also discloses a method for using the model test device. The present invention can accurately restore the actual geological conditions of the area where the tunnel is to be built and comprehensively restore the construction process of the horizontal jet grouting piles. The test results are highly reliable and have high reference value, and can provide an effective reference for judging the feasibility of horizontal jet grouting piles in actual tunnel construction scenarios.

Description

Technical Field

[0001] The invention relates to the technical field of aeolian sand tunnels, and in particular to a model test device for simulating the establishment of tunnel jet grouting piles and a use method thereof. Background Art

[0002] In the related art of constructing railway tunnels in aeolian sand formations, due to the low cohesion and loose structure of aeolian sand, the shear resistance of the aeolian sand base is weak, making it prone to dangerous accidents such as collapse and sand surge at the tunnel face during tunnel construction. To ensure the safe progress of construction, advance support of the tunnel is required to increase the bearing capacity of the loose soil. In related art, vertical jet grouting piles are commonly used to reinforce aeolian sand formations. However, vertical jet grouting piles can only effectively fix the sand when they are long, making them unsuitable for shorter tunnels. Furthermore, laying large numbers of them would impose a significant economic burden. In comparison, horizontal jet grouting piles are more cost-effective. Research on horizontal jet grouting piles has mostly used precast piles to analyze their support effect on tunnels, but has failed to study the impact of the horizontal jet grouting pile formation process on aeolian sand formations. Related art currently lacks reliable experimental support for horizontal jet grouting piles, making their safety and reinforcement effectiveness difficult to predict and determining their applicability in actual construction scenarios. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a model test apparatus and method for simulating the establishment of tunnel jet grouting piles. The model test is used to study the impact of the establishment process of horizontal jet grouting piles in aeolian sand strata on the stratum. This method can accurately simulate working conditions in a time-saving and efficient manner. The test results are of great reference value for feasibility research on horizontal jet grouting piles.

[0004] The present invention proposes a model test equipment for simulating the establishment of tunnel jet grouting piles, comprising: a box, a sensor, a pressure regulating device, and a jet grouting device. A soil model is arranged in the box, and the soil model forms a simulated tunnel lining; the sensor is arranged in the soil model and is suitable for monitoring the pressure around the simulated tunnel lining; the pressure regulating device is arranged in the box, and is suitable for adjusting the pressure applied to the soil model; the jet grouting device is formed with a drill bit suitable for jet grouting the soil model, and the jet grouting device is movably arranged in the box to selectively perform jet grouting on the soil model around the simulated tunnel lining.

[0005] According to an embodiment of the present invention, since the soil model is subject to adjustable pressure and a simulated tunnel lining is set in the soil model, this embodiment can accurately restore the actual geological conditions of the tunnel area to be built, and use a rotary jet device to simulate rotary jet grouting to set horizontal rotary jet piles on the soil model, and monitor the pressure changes of the peripheral soil layer of the simulated tunnel lining in real time through sensors; this embodiment can accurately restore the geological characteristics and comprehensively restore the construction process of the horizontal rotary jet piles. The test results have high reliability and reference value, and can provide an effective reference for judging the feasibility of horizontal rotary jet piles in actual tunnel construction scenarios.

[0006] According to some embodiments of the present invention, the rotary jetting device includes: a mounting frame and a rotary jetting body; the mounting frame can be arranged on the box body for translation along a first direction, and the mounting frame extends in a second direction; the rotary jetting body can be movably arranged along the mounting frame to be selectively moved to any position on the end face of the soil model.

[0007] According to some embodiments of the present invention, the box body is provided with a first sliding part, and the mounting frame is provided with a second sliding part suitable for cooperating with the first sliding part, and the second sliding part moves relative to the first sliding part to drive the mounting frame to move relative to the box body; the mounting frame is slidably provided with a connecting mechanism, and one end of the connecting mechanism is fixed on the rotary spraying body to drive the rotary spraying body to move relative to the mounting frame.

[0008] According to some embodiments of the present invention, the second sliding part is provided with a locking part, which is suitable for selectively limiting the movement of the second sliding part relative to the first sliding part; and limiting parts are provided at both ends of the first sliding part, which are suitable for limiting the movement range of the second sliding part.

[0009] According to some embodiments of the present invention, the connecting mechanism includes: a fixing portion and a connecting arm; the fixing portion is arranged on the rotary spraying body; one end of the connecting arm is rotatably connected to the fixing portion, and the other end of the connecting arm is provided with a claw; wherein the connecting arm is constructed in at least two, and the connecting arm rotates so that the claws can selectively approach or move away from each other; when the claws approach, they cooperate to surround the mounting frame and are suitable for sliding relative to the mounting frame.

[0010] According to some embodiments of the present invention, at least one of the claws is provided with a magnet, and the two mating claws are kept connected by the magnetic force of the magnet.

[0011] According to some embodiments of the present invention, the rotary grouting body includes: a carrying platform, a drill rod, a slurry conveying mechanism, a first motor and a second motor; the carrying platform is movably arranged on the mounting frame; the drill rod is movably arranged on the carrying platform, and a detachable drill bit is provided at the end of the drill rod; a grouting channel suitable for slurry circulation is formed inside the drill rod, and the drill bit is formed with a plurality of grouting ports connected to the grouting channel; the slurry conveying mechanism is connected to the grouting channel, and the slurry conveying mechanism is provided with a pressure pump, which is suitable for conveying slurry to the drill bit and adjusting the grouting pressure; the first motor and the second motor are arranged on the carrying platform, and the first motor is suitable for driving the drill rod away from or close to the soil model; the second motor is suitable for driving the drill rod to rotate.

[0012] According to some embodiments of the present invention, the carrying platform includes: a base and a drill rod mounting portion; the base is movably arranged on the mounting frame, and a movable channel extending in a third direction is formed on the base; the drill rod mounting portion is movably arranged in the movable channel, and a drill rod is provided on the drill rod mounting portion and is suitable for driving the drill rod mounting portion to move in the third direction.

[0013] According to some embodiments of the present invention, a rack extending along the third direction is formed on one side of the drill rod mounting portion, and a first driving gear meshing with the rack is provided at the output end of the first motor.

[0014] According to some embodiments of the present invention, a rotating disk is rotatably provided on the drill rod mounting portion, and the rotating disk is connected to the drill rod to drive the drill rod to rotate; a transmission gear is formed on the rotating disk, and a second motor is provided on the drill rod mounting portion, and a second driving gear meshing with the transmission gear is provided at the output end of the second motor.

[0015] The present invention also provides a method for using the above-mentioned model test equipment, comprising the following steps:

[0016] S1. Obtain target parameters of the soil model according to the environmental parameters of the target area, and set the corresponding soil model in the model test equipment;

[0017] S2. Obtaining working parameters of the rotary jet grouting device according to target parameters of the soil model, and controlling the rotary jet grouting device to perform rotary jet grouting on the soil model;

[0018] S3. Obtain mechanical monitoring data from sensors corresponding to the simulated tunnel lining, and determine the construction feasibility of the target area based on the mechanical monitoring data.

[0019] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0021] Figure 1 is a structural schematic diagram of a model test device according to one embodiment of the present invention;

[0022] Figure 2 is a structural schematic diagram of a connecting mechanism in a state where it is not assembled with a mounting frame according to an embodiment of the present invention;

[0023] Figure 3 is a structural schematic diagram of the connection mechanism and the mounting frame in an assembled state according to one embodiment of the present invention;

[0024] Figure 4 2 is a schematic structural diagram of a rotary spraying body according to an embodiment of the present invention.

[0025] Reference numerals:

[0026] Box 10; soil model 20; simulated tunnel lining 21; sensor 30; pressure regulating device 40;

[0027] Mounting frame 50; mounting frame legs 51;

[0028] Jet grouting body 60; drill rod 61; drill bit 62; drill rod mounting portion 63; first motor 641; first driving gear 642; rack 643; second motor 651; second driving gear 652; rotating disk 653; transmission gear 654; slurry conveying mechanism 66; pipeline 661; pressure pump 662; slurry tank 663; computer integrated module 67;

[0029] First sliding portion 71; second sliding portion 72;

[0030] Connecting mechanism 80; fixing portion 81; connecting arm 82; claw 83; magnet 84

[0031] Box legs 90. DETAILED DESCRIPTION

[0032] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0033] Reference below Figure 1-Figure 3 A model test device for simulating the establishment of tunnel jet grouting piles according to an embodiment of the present invention is described. The model test device is mainly used to study the impact of jet grouting on the establishment of jet grouting piles on aeolian sand formations, but is not limited to aeolian sand formations. It can also be used to study the impact of jet grouting on other formations.

[0034] The present invention proposes a model test equipment for simulating the establishment of tunnel jet grouting piles, comprising: a box 10, a sensor 30, a pressure regulating device 40, and a jet grouting device. A soil model 20 is arranged in the box 10, and the soil model 20 forms a simulated tunnel lining 21; the sensor 30 is arranged in the soil model 20 and is suitable for monitoring the pressure around the simulated tunnel lining 21; the pressure regulating device 40 is arranged in the box 10, and the pressure regulating device 40 is suitable for adjusting the pressure applied to the soil model 20; the jet grouting device is formed with a drill bit suitable for jet grouting the soil model 20, and the jet grouting device is movably arranged in the box 10 to selectively perform jet grouting on the soil model 20 around the simulated tunnel lining 21.

[0035] According to an embodiment of the present invention, a soil model 20 with a simulated tunnel lining 21 is provided to simulate the actual tunnel area strata, and a pressure regulating device 40 is used to apply pressure to the soil model 20 to simulate the actual pressure environment conditions of the underground soil layer, which can accurately restore the stratum characteristics and improve the reference value of the test results; this embodiment uses a rotary jet grouting device to perform rotary jet grouting on the soil model 20 to simulate the setting of horizontal rotary jet piles during the actual tunnel construction process, and uses a sensor 30 to monitor the pressure changes of the soil layer around the simulated tunnel lining 21 in real time; the rotary jet grouting device can be moved arbitrarily, can meet the simulated grouting needs of different positions, and can perform multiple grouting tests in a relatively comprehensive sequence, thereby simulating the joint action of multiple rotary jet piles in the actual scene, with high integrity and high reliability of the test results.

[0036] According to an embodiment of the present invention, since the soil model 20 is pressure-adjustable and a simulated tunnel lining 21 is set in the soil model 20, this embodiment can accurately restore the actual geological conditions of the tunnel area to be built, and use a rotary jet device to simulate rotary jet grouting to set horizontal rotary jet piles on the soil model 20, and monitor the pressure changes of the soil layer around the simulated tunnel lining 21 in real time through the sensor 30; this embodiment can accurately restore the geological characteristics and comprehensively restore the construction process of the horizontal rotary jet piles. The test results are highly reliable and have high reference value, and can provide an effective reference for judging the feasibility of horizontal rotary jet piles in actual tunnel construction scenarios.

[0037] In addition, the model test equipment of the embodiment of the present invention can also be used to establish a rotary jet pile model to further study the supporting effect of horizontal rotary jet piles on tunnels. Compared with prefabricated rotary jet piles inserted into the stratum, the rotary jet piles established by grouting can better retain and restore the characteristics of the stratum around the tunnel.

[0038] like Figure 1As shown, in some embodiments, two pressure regulating devices 40 may be provided, each applying pressure to the soil model 20 in mutually perpendicular directions to simulate the actual pressure environment of the underground soil layer. Furthermore, during the pressure regulation process, the pressure regulation accuracy can be determined based on the monitoring data of the sensor 30 to reduce errors. In some embodiments, the pressure regulating device 40 can be configured as a hydraulic press for easy control.

[0039] In some embodiments, multiple sensors 30 may be provided, dispersedly arranged along the periphery of the simulated tunnel lining 21. Providing multiple sensors 30 can improve the accuracy of monitoring for different grouting hole locations. In some embodiments, the sensors 30 may be configured as pressure gauges.

[0040] According to some embodiments of the present invention, a jet grouting device includes: a mounting frame 50 and a jet grouting body; the mounting frame 50 can be arranged on the housing 10 so as to be translatable along a first direction, and the mounting frame 50 extends in a second direction; the jet grouting body can be movably arranged along the mounting frame 50 to selectively move to any position on the end surface of the soil model 20. In this embodiment, the jet grouting body can be moved in the second direction relative to the mounting frame 50, and the mounting frame 50 can be moved in the first direction relative to the housing 10. Therefore, the jet grouting body can move in a combination of the first and second directions to achieve arbitrary movement within the installation plane. In some embodiments, the first and second directions can be one of the height direction and the width direction of the housing 10, respectively.

[0041] In some embodiments, a mounting frame leg 51 is provided at the bottom of the mounting frame 50. The mounting frame leg 51 is constructed as a retractable structure with adjustable height. It can share the weight of the mounting frame 50 and the rotary spraying body 60, reduce the load on the box 10, and avoid the model test equipment from becoming unstable due to the offset of the center of gravity.

[0042] According to some embodiments of the present invention, the housing 10 is provided with a first sliding portion 71, and the mounting frame 50 is provided with a second sliding portion 72 adapted to cooperate with the first sliding portion 71. The second sliding portion 72 moves relative to the first sliding portion 71 to drive the mounting frame 50 to move relative to the housing 10. The mounting frame 50 is slidably provided with a connecting mechanism 80, one end of which is fixed to the jet grouting body 60 to drive the jet grouting body 60 to move relative to the mounting frame 50. In this embodiment, the jet grouting body 60 is fixedly connected to the connecting mechanism 80, so that the jet grouting body 60 and the connecting mechanism 80 can move synchronously along the mounting frame 50. The mounting frame 50 is moved relative to the housing 10 by the first sliding portion 71 and the second sliding portion 72, thereby enabling the jet grouting body 60 to move arbitrarily on the end surface of the soil model 20.

[0043] In some embodiments, the first sliding portion 71 is configured as a slide rail, and the second sliding portion 72 is configured as a pulley. The slide rail can be installed on the side panels of the box 10, and the pulleys are installed at both ends of the mounting frame 50, respectively engaging with the slide rails on both sides of the box 10. The combination of pulleys and slide rails in this embodiment can make the movement of the mounting frame 50 smoother.

[0044] It should be noted that when the mounting frame 50 moves relative to the box body 10, it is necessary to apply drive and braking to the mounting frame 50 or any one of the first sliding part 71 and the second sliding part 72; when the rotary spray body 60 moves relative to the mounting frame 50, it is necessary to apply drive and braking to any one of the rotary spray body 60 or the connecting mechanism 80.

[0045] To simplify the structure, in the embodiment of the present invention, as Figure 1 As shown, there are two mounting brackets 50 and they are arranged perpendicular to each other. There are two groups of connecting mechanisms 80, which are slidably connected to one of the mounting brackets 50 and fixedly connected to the jet grouting body 60. Based on this, when one of the mounting brackets 50 moves, it can drive the jet grouting body 60 to move along the extension direction of the other mounting bracket 50, while the other mounting bracket 50 limits the freedom of the jet grouting body 60 to move in other directions. In this embodiment, the movement of the two groups of mounting brackets 50 can drive the jet grouting body 60 to achieve a combined movement along the extension direction of the two mounting brackets 50, thereby achieving arbitrary movement of the jet grouting body 60 on the end face of the soil model 20; the position locking of the jet grouting body 60 can be achieved by the relative stillness of the two mounting brackets 50; there is no need to apply drive or brake to the jet grouting body 60, the structure is simpler, more efficient and more stable; at the same time, the movement process of the jet grouting body 60 is more stable and easier to control.

[0046] According to some embodiments of the present invention, the second sliding portion 72 is provided with a locking portion, which is suitable for selectively limiting the movement of the second sliding portion 72 relative to the first sliding portion 71; and limiting portions are provided at both ends of the first sliding portion 71, which are suitable for limiting the movement range of the second sliding portion 72. In this embodiment, the locking portions can stop the movement of the mounting frame 50 relative to the box body 10 and keep it in the stopped position, so as to temporarily fix the position of the jet grouting body 60 in the first direction for grouting at a fixed hole position; the limiting portions limit the movement range of the mounting frame 50 relative to the box body 10, preventing the mounting frame 50 from detaching from the box body 10 and preventing the mounting frame 50 from driving the jet grouting body 60 beyond the area of ​​the soil model 20, thereby making the movement of the jet grouting body 60 more reliable.

[0047] According to some embodiments of the present invention, the connecting mechanism 80 includes: a fixing portion 81 and a connecting arm 82; the fixing portion 81 is provided on the jet spraying body 60; one end of the connecting arm 82 is rotatably connected to the fixing portion 81, and the other end of the connecting arm 82 is provided with a claw 83; wherein the connecting arm 82 is constructed in at least two pieces, and the connecting arm 82 rotates so that the claws 83 can selectively move closer to or farther away from each other; when the claws 83 are close, they cooperate to surround the mounting frame 50 and are suitable for sliding relative to the mounting frame 50. This embodiment utilizes the combination of the claws 83 to form an enclosing structure suitable for sliding relative to the mounting frame 50, so as to achieve a slidable connection between the jet spraying body 60 and the mounting frame 50. In some embodiments, such as Figure 2 、 Figure 3 As shown, the connecting arm 82 is provided with two groups, and a claw 83 is provided on each opposite side. The claw 83 is an open structure. When the two claws 83 are connected, a closed surrounding structure is formed to restrict the mounting frame 50 in the middle. By rotating the connecting arm 82, the claw 83 can be moved closer or farther away, thereby facilitating the assembly and connection with the mounting frame 50 and facilitating the slidable placement of the jet spray body 60 on the mounting frame 50. Figure 2 As shown, when the connecting mechanism 80 is not assembled on the mounting frame 50 to realize the connection between the rotary spraying body 60 and the mounting frame 50, the two claws 83 are separated; Figure 3 As shown, when the connecting mechanism 80 is assembled on the mounting frame 50, the two claws 83 are connected to form an enclosing structure. In some embodiments, to improve the adaptability of the claw 83 to the mounting frame 50, the claw 83 is rotatably connected to the connecting arm 82; the connecting arm 82, the fixing portion 81, and the claw 83 can all be relatively rotatable via bearings. In some embodiments, the claw 83 is formed with a palm portion and rotatably provided with at least two finger joints, which are disposed on the palm portion via bearings. When the jet spray body 60 of this embodiment is installed on the mounting frame 50, the claw 83 can rotate the finger joints to move closer to and surround the mounting frame 50, making it easier to clamp around the periphery of the mounting frame 50.

[0048] According to some embodiments of the present invention, at least one claw 83 is provided with a magnet 84, and the two matching claws 83 are kept connected by the magnetic force of the magnet 84. In this embodiment, the connection between the claws 83 is maintained by the magnetic force generated between the magnets 84 or between the magnet 84 and the claws 83, without the need for a separate mechanism to limit the relative movement of the claws 83. The magnets 84 can be arranged in a variety of ways and are easy to implement, making the structure simple and easy to operate and install. At the same time, the magnets 84 can provide a long-term and effective holding force on the claws 83. In some embodiments, such as Figure 2 、 3 As shown, magnets 84 are provided at the ends of the two claws 83 .

[0049] According to some embodiments of the present invention, the rotary grouting body 60 includes: a carrying platform, a drill rod 61, a slurry conveying mechanism 66, a first motor 641 and a second motor 651; the carrying platform is movably arranged on the mounting frame 50; the drill rod 61 is movably arranged on the carrying platform, and a detachable drill bit 62 is provided at the end of the drill rod 61; a grouting channel suitable for slurry circulation is formed inside the drill rod 61, and the drill bit 62 is formed with a plurality of grouting ports connected to the grouting channel; the slurry conveying mechanism 66 is connected to the grouting channel, and the slurry conveying mechanism 66 is provided with a pressure pump 662, which is suitable for conveying slurry to the drill bit 62 and adjusting the grouting pressure; the first motor 641 and the second motor 651 are arranged on the carrying platform, and the first motor 641 is suitable for driving the drill rod 61 away from or close to the soil model 20; the second motor 651 is suitable for driving the drill rod 61 to rotate.

[0050] The slurry conveying mechanism 66 of this embodiment conveys slurry to the drill rod 61 at a certain pressure. The slurry flows through the grouting channel to the drill bit 62 and is ejected through the grouting port provided by the drill bit 62. The high-speed jetted liquid flow has a highly concentrated energy, which can destroy the soil. The drill bit 62 of this embodiment is detachable and easy to replace. During the grouting process, the second motor 651 drives the drill rod 61 and the drill bit 62 to rotate at high speed. At the same time, the first motor 641 drives the drill rod 61 and the drill bit 62 to approach each other and gradually drill into the soil model 20 by relying on the impact force of the slurry rotation jet. Since the drill rod 61 and the drill bit 62 perform grouting by rotary jetting, the slurry is fully stirred and mixed with the soil after being ejected, forming a columnar consolidation body, i.e., a rotary jet pile, in the grouting hole. The rotary jetting body 60 of this embodiment can complete rotary jet grouting for a fixed hole position, accurately simulate the actual construction process of a horizontal rotary jet pile, and has a high reference value for studying the application of horizontal rotary jet piles.

[0051] In some embodiments of the present invention, Figure 4 As shown, the slurry conveying mechanism 66 includes a conveying pipeline 661, a slurry tank 663 and a pressure pump 662. The conveying pipeline 661 is connected to the grouting channel and the slurry tank 663, and the pressure pump 662 is arranged in the conveying pipeline 661 and is suitable for conveying slurry and adjusting the grouting pressure. The slurry tank 663 of this embodiment is equipped with configured slurry, and the pressure pump 662 extracts the slurry and conveys the slurry to the drill rod 61 and the drill bit 62. The slurry passes through the conveying pipeline 661, the grouting channel and is continuously rotated and ejected through the grouting port. The position of the slurry tank 663 of this embodiment can be set arbitrarily, and is not limited to being set on the rotary grouting body 60. It can be set on the test workbench without affecting the connection between the pipeline and the drill rod 61, and can reduce the load of the rotary grouting body 60, thereby ensuring the stability of the slurry conveying.

[0052] According to some embodiments of the present invention, the mounting platform includes: a base and a drill rod mounting portion 63; the base is movably mounted on the mounting frame 50, and a movable channel extending in a third direction is formed on the base; the drill rod mounting portion 63 is movably mounted within the movable channel, and a drill rod 61 is mounted on the drill rod mounting portion 63 and is suitable for driving the drill rod mounting portion 63 to move in the third direction. In this embodiment, the third direction is a direction perpendicular to the end face of the soil model 20; the base is slidably mounted on the mounting frame 50 along a second direction; the drill rod mounting portion 63 is slidably connected to the base along the third direction; the drill rod 61 is mounted on the drill rod mounting portion 63, thereby enabling the drill rod 61 to move relative to the base, thereby driving the drill bit 62 to move closer to or further away from the soil model 20. In this embodiment, the drill rod 61 can accurately move to the soil model 20 for drilling by superimposing the movements of the base and the drill rod mounting portion 63.

[0053] According to some embodiments of the present invention, Figure 4 As shown, a rack 643 extending in a third direction is formed on one side of the drill rod mounting portion 63. A first driving gear 642 meshing with the rack 643 is provided at the output end of the first motor 641. In this embodiment, the first motor 641 drives the drill rod mounting portion 63 via a rack-and-pinion mechanism to move the drill rod 61 and drill bit 62 closer to or further away from the soil model 20. Because the rack-and-pinion mechanism can provide a large driving force while also bearing a large reverse force, it can provide sufficient driving force for the drill rod 61 to break the soil during drilling, ensuring stable grouting depth of the drill rod 61.

[0054] According to some embodiments of the present invention, a rotating disk 653 is rotatably provided on the drill rod mounting portion 63. The rotating disk 653 is connected to the drill rod 61 to drive the drill rod 61 to rotate. A transmission gear 654 is formed on the rotating disk 653. A second motor 651 is disposed on the drill rod mounting portion 63. The output end of the second motor 651 is provided with a second driving gear 652 that meshes with the transmission gear 654. In this embodiment, the second motor 651 drives the gear assembly to rotate the drill rod 61. The provision of the rotating disk 653 facilitates the rotatable connection between the drill rod 61 and the drill rod mounting portion 63, thereby facilitating communication between the drill rod 61 and the slurry conveying mechanism 66.

[0055] According to some embodiments of the present invention, at least two sets of box legs 90 are provided at the bottom of the box 10. The box legs 90 are adapted to be adjustable in length to adjust the height of the box 10. By adjusting the height of the box 10, the box 10 can be balanced and the overall stability of the model test equipment can be improved.

[0056] According to some embodiments of the present invention, the model test equipment further includes a control unit adapted to receive real-time soil pressure data from the simulated tunnel lining 21 monitored by sensors 30 and to control the jet grouting device to perform jet grouting. Specifically, the control unit includes a computer integrated module 67 disposed within the jet grouting body 60. The computer integrated module 67 is connected to the first motor 641 and the second motor 651 and instructs the first motor 641 and the second motor 651 to rotate. Furthermore, the computer integrated module 67 is provided with a Bluetooth module adapted to remotely receive command signals from the control unit and transmit them to the computer integrated module 67 for transmission to the first motor 641 and the second motor 651. In this embodiment, the control unit can set the operating parameters of the first motor 641 and the second motor 651 and issue motion commands to them to drive the drill rod 61 for rotational drilling. During the jet grouting process, the control unit can receive and record real-time pressure data monitored by each sensor 30 for analysis of the impact of horizontal jet grouting. In addition, the control unit is adapted to input and record the basic parameters of the soil model 20 and automatically calculate the grouting parameters and the operating parameters of the first motor 641 and the second motor 651 based on the input parameters. This embodiment, by providing a control unit, can improve the automation level of the model test equipment, making the test process based on data visualization, more conducive to understanding the test process and improving the degree of restoration of the actual construction process, thereby increasing the reference value of the test. In some embodiments, the control unit can be configured as a central control computer to facilitate subsequent analysis.

[0057] The present invention also provides a method for using the above-mentioned model test equipment, comprising the following steps:

[0058] S1. Obtain target parameters of the soil model 20 according to the environmental parameters of the target area, and set the corresponding soil model 20 in the model test equipment;

[0059] S2, obtaining the working parameters of the rotary jet grouting device according to the target parameters of the soil model 20, and controlling the rotary jet grouting device to perform rotary jet grouting on the soil model 20;

[0060] S3. Obtain mechanical monitoring data of the simulated tunnel lining 21 corresponding to the sensor 30, and determine the construction feasibility of the target area based on the mechanical monitoring data.

[0061] According to the method of this embodiment, the horizontal rotary jet grouting construction process can be restored using model test equipment, and the feasibility of horizontal rotary jet grouting can be analyzed based on the test results; and the establishment of a model can repeat the test, reduce errors, and improve the reliability of the test results.

[0062] In S1 , target parameters of the soil model 20 are determined according to the environmental parameters of the target area, which can highly understand the soil environment of the target area, thereby making the reference value of the test results using the model test equipment of the present application higher.

[0063] In some embodiments, step S1 of the above-mentioned method for using the model test equipment specifically includes: measuring the actual soil cover thickness, soil density, soil pressure, and porosity of the area to be constructed, establishing a soil model 20 based on the similarity principle, and applying pressure to the soil model 20 using a pressure regulating device 40. During the process of establishing the soil model 20 and adjusting the soil pressure, data monitored by the sensor 30 can be used to determine in real time whether the soil pressure has been adjusted to the target value. This allows visualization of the pressure parameters of the soil model 20 during the establishment process, enabling real-time adjustments based on the data, eliminating the need for additional measurements and repeated pressure adjustments, and improving model establishment efficiency.

[0064] It should be noted that the similarity principle refers to the three major similarity theorems, namely: (1) For two similar systems with the same single-valued conditions, the numerical values ​​of their similarity criteria are also the same; (2) When a phenomenon is represented by the functional relationship of n physical quantities, and these physical quantities contain m basic dimensions, (nm) similarity criteria can be obtained; (3) For any phenomenon with the same characteristics, when the single-valued conditions (geometric properties of the system, physical properties of the medium, initial conditions and boundary conditions, etc.) are similar to each other, and the similarity criteria composed of the physical quantities of the single-valued conditions are numerically equal, then these phenomena must be similar.

[0065] According to the similarity principle, step S1 can determine the relevant parameters of the soil model 20 of this embodiment through the model similarity ratio of parameters such as geometry, stress, elastic modulus, Poisson's ratio, cohesion, density, and internal friction angle, and establish the soil model 20 based on this to restore the physical characteristics of the actual formation environment as much as possible.

[0066] In some embodiments, step S2 of the above-mentioned method for using the experimental device specifically includes:

[0067] S2.1. Calculate the grouting pressure, grouting volume per linear meter, and grouting slurry ratio based on the soil cover thickness, soil pressure, soil density, and porosity of the soil model 20;

[0068] S2.2. Set the drilling depth, drilling area, drilling pressure, and speed of the drill rod 61. The control unit automatically calculates and configures the parameters of the first motor 641 and the second motor 651. Set the grouting pressure of the pressure pump 662 based on the calculation results of S2.1, and perform a slurry test to test the smoothness of slurry delivery.

[0069] S2.3. Determine the hole positions for horizontal drilling on the face of the soil model 20, move the jet grouting device to the hole positions one by one, and start jet grouting until the grouting is completed; during the grouting process, record the pressure data monitored by the sensor 30 at all times.

[0070] In S2.1 of this embodiment, the soil cover thickness is denoted as h, the soil density is denoted as γ, the grouting pressure is denoted as P, and the grouting volume per linear meter is denoted as Q, and the following conditions are satisfied:

[0071] Grouting pressure P=k1·γ·h

[0072] Wherein, k1 is the pressure coefficient; in some embodiments, k1 can be 1.3;

[0073] Grouting volume per meter Q = k2·v·n, v = s·d

[0074] Wherein, k2 is the slurry filling coefficient, v is the volume of the sand consolidation body, s is the preset cross-sectional area of ​​the borehole, and d is the preset borehole depth; in some embodiments, k2=0.6-0.7;

[0075] Grouting slurry ratio: water-cement ratio = 0.8~1.2.

[0076] In this embodiment, the grouting parameters are determined by the parameters of the soil model 20, and the relationship between the soil parameters and the grouting parameters is clear, so the influence of grouting on the soil can be studied in a targeted manner. When repeating the test, the result deviation caused by the difference in soil parameters can be avoided. The method of this embodiment has high flexibility and adaptability.

[0077] Furthermore, the control unit of this embodiment can preset the conversion relationship between parameters and automatically calculate the input measurement data, which can simplify the calculation process and improve the test efficiency.

[0078] In some embodiments, step S3 of the method for using the model test equipment specifically includes: deriving pressure data and plotting time-varying curves of contact pressure and tangential stress based on the monitored pressure data, thereby analyzing the pressure changes in the simulated tunnel lining 21 during the grouting process to form jet grouting piles; determining whether the grouting process is dangerous or potentially hazardous based on whether the pressure value exceeds a standard range, and predicting the feasibility of performing high-pressure jet grouting during actual construction. In step S3 of this embodiment, if the pressure value exceeds the standard range, it indicates that the construction of the horizontal jet grouting piles poses a risk of collapse of the aeolian sand stratum and is not feasible for practical application.

[0079] This embodiment uses pressure data to determine the stability of the soil model during simulated jet grouting pile construction, thereby inferring the stability of the actual ground environment during jet grouting pile construction under similar conditions. Because damage and deformation of the ground environment are the result of force, pressure is the most direct reflection of the impact on the soil, resulting in a highly reliable measurement result. Furthermore, pressure data exhibits significant variations, facilitates the establishment of a standard range, facilitates measurement, and facilitates comparison, thus reducing the burden of testing and minimizing judgment errors.

[0080] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0081] In the description of the present invention, "first feature" and "second feature" may include one or more of the features.

[0082] In the description of the present invention, "plurality" means two or more.

[0083] In the description of the present invention, a first feature being “on” or “under” a second feature may include the first and second features being in direct contact with each other, or the first and second features not being in direct contact with each other but being in contact with each other via another feature therebetween.

[0084] In the description of the present invention, “on”, “above” and “above” a first feature of a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0085] Throughout this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "example," "specific example," or "some examples" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0086] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A model test equipment for simulating the establishment of tunnel jet grouting piles, characterized in that: include: A box body, wherein a soil model is arranged in the box body, and the soil model forms a simulated tunnel lining; a sensor disposed in the soil model and adapted to monitor the pressure around the simulated tunnel lining; A pressure regulating device, the pressure regulating device being arranged in the box body and being suitable for adjusting and applying pressure to the soil model; A jet grouting device, the jet grouting device being formed with a drill bit suitable for jet grouting the soil model, the jet grouting device being movably arranged on the housing; the jet grouting device being suitable for simulating jet grouting of the soil model around the tunnel lining, so as to simulate the installation of horizontal jet grouting piles during the tunnel construction process; The rotary spraying device comprises: a mounting frame, the mounting frame being arranged on the box body so as to be movably disposed along a first direction, and the mounting frame extending in a second direction; The rotary grouting body is movably arranged along the mounting frame so as to be movable to any position of the end surface of the soil model.

2. The model test equipment according to claim 1, characterized in that The box body is provided with a first sliding part, and the mounting frame is provided with a second sliding part suitable for cooperating with the first sliding part, and the second sliding part moves relative to the first sliding part to drive the mounting frame to move relative to the box body; the mounting frame is slidably provided with a connecting mechanism, and one end of the connecting mechanism is fixed on the rotary spraying body to drive the rotary spraying body to move relative to the mounting frame.

3. The model test equipment according to claim 2, characterized in that: The second sliding part is provided with a locking part, which is suitable for limiting the movement of the second sliding part relative to the first sliding part; both ends of the first sliding part are provided with limiting parts, which are suitable for limiting the movement range of the second sliding part.

4. The model test equipment according to claim 3, characterized in that The connecting mechanism comprises: A fixing portion, the fixing portion being arranged on the rotary spraying body; A connecting arm, one end of which is rotatably connected to the fixing portion, and the other end of which is provided with a claw; The connecting arms are constructed in the form of at least two, and the connecting arms rotate to make the claws approach or move away from each other; when the claws approach each other, they cooperate to surround the mounting bracket and are suitable for sliding relative to the mounting bracket.

5. The model test equipment according to claim 4, characterized in that: At least one of the claws is provided with a magnet, and the two matching claws are kept connected by the magnetic force of the magnet.

6. The model testing equipment according to claim 1, characterized in that The rotary spraying body comprises: a carrying platform, the carrying platform being movably disposed on the mounting frame; A drill rod, the drill rod being movably mounted on the carrying platform, the end of the drill rod being provided with a detachable drill bit; a grouting channel suitable for slurry circulation is formed inside the drill rod, and the drill bit is formed with a plurality of grouting ports communicating with the grouting channel; a slurry delivery mechanism, the slurry delivery mechanism being in communication with the grouting channel and being provided with a pressure pump, the pressure pump being adapted to deliver slurry to the drill bit and adjust the grouting pressure; A first motor and a second motor are provided on the carrying platform. The first motor is suitable for driving the drill rod away from or close to the soil model; the second motor is suitable for driving the drill rod to rotate.

7. The model testing equipment according to claim 6, characterized in that The carrying platform includes: a base, the base being movably disposed on the mounting frame, and having a movable channel extending in a third direction; A drill rod mounting portion is movably disposed in the movable channel, the drill rod mounting portion is provided with the drill rod and is suitable for driving the drill rod mounting portion to move in a third direction.

8. The model testing equipment according to claim 7, characterized in that A rack extending along a third direction is formed on one side of the drill rod mounting portion, and a first driving gear meshing with the rack is provided at the output end of the first motor.

9. The model testing equipment according to claim 7, characterized in that: A rotating disk is rotatably provided on the drill rod mounting portion, and the rotating disk is connected to the drill rod to drive the drill rod to rotate; A transmission gear is formed on the rotating disk, the second motor is arranged on the drill rod mounting portion, and an output end of the second motor is provided with a second driving gear meshing with the transmission gear.

10. A method for using the model test equipment according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Obtain target parameters of the soil model according to environmental parameters of the target area, and set a corresponding soil model in a model test device; S2, obtaining working parameters of the rotary jet grouting device according to the target parameters of the soil model, and controlling the rotary jet grouting device to perform rotary jet grouting on the soil model; S3. Obtain mechanical monitoring data from sensors corresponding to the simulated tunnel lining, and determine the construction feasibility of the target area based on the mechanical monitoring data.

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