Model test equipment for simulating building of tunnel jet grouting pile and use method

Abstract

The invention discloses model test equipment for simulating establishment of a tunnel jet grouting pile, which comprises a box body, a sensor, a pressure regulating device and a jet grouting device, and is characterized in that a soil body model is arranged in the box body, and a simulated tunnel lining is formed on the soil body model; the sensor is arranged in the soil body model and is suitable for monitoring the pressure of the periphery of the simulated tunnel lining; the pressure adjusting device is arranged in the box body and is suitable for adjusting and applying pressure to the soil body model; a drill bit suitable for performing rotary jet grouting on the soil body model is formed on the rotary jet grouting device, and the rotary jet grouting device is movably arranged on the box body so as to selectively perform rotary jet grouting on the soil body model around the simulated tunnel lining. The invention further discloses a using method of the model test equipment. According to the method, the actual stratum condition of the to-be-built tunnel area can be accurately restored, the construction process of the horizontal jet grouting pile can be comprehensively restored, the reliability and reference value of the test result are high, and effective reference can be provided for judging the feasibility of the horizontal jet grouting pile in an actual tunnel construction scene.

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 relevant technologies for constructing railway tunnels in aeolian sand strata, due to the low cohesion and loose structure of aeolian sand, the shear resistance of the aeolian sand bottom layer is weak, and dangerous accidents such as collapse and sand surge are prone to occur at the face during tunnel construction. In order to ensure the safe advancement of engineering construction, it is necessary to carry out advance support for the tunnel to increase the bearing capacity of the loose soil. In the relevant technologies, vertical jet grouting piles are generally used to reinforce aeolian sand strata. However, vertical jet grouting piles can only fix sand and soil well when the length is long, which is not suitable for shorter tunnels, and large-scale laying will cause serious economic burden; in contrast, horizontal jet grouting piles are cheaper. However, the research on horizontal jet grouting piles mostly uses prefabricated piles to analyze the supporting effect of prefabricated piles on tunnels, and it is impossible to study the impact of the formation process of horizontal jet grouting piles on aeolian sand strata. In the relevant technologies, horizontal jet grouting piles currently lack reliable test support, and their safety and reinforcement effects are difficult to predict, and it is impossible to determine whether they can be applied 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 purpose of the present invention is to propose a model test device and a method for using the device to simulate the establishment of tunnel jet grouting piles, and to use the model test to study the influence of the establishment process of horizontal jet grouting piles in aeolian sand strata on the strata, which can save time and efficiently and accurately simulate the working conditions, and the test results have important reference value for the feasibility study of 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 the pressure regulating device 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 pressure of the soil model is adjustable 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 the rotary jet grouting of the soil model to set up horizontal rotary jet piles, and use sensors to monitor the pressure changes of the surrounding soil layer of the simulated tunnel lining in real time; 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 jet spraying device includes: a mounting frame and a rotary jet spraying 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 jet spraying body can be movably arranged along the mounting frame to be selectively moved to any position of 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 portion is provided with a locking portion, which is suitable for selectively limiting the movement of the second sliding portion relative to the first sliding portion; limiting portions are provided at both ends of the first sliding portion, which are suitable for limiting the movement range of the second sliding portion.

[0009] According to some embodiments of the present invention, the connecting mechanism includes: a fixing part and a connecting arm; the fixing part is arranged on the rotary spraying body; one end of the connecting arm is rotatably connected to the fixing part, and the other end of the connecting arm is provided with a claw; wherein the connecting arm is constructed of 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 matching claws are kept connected by the magnetic force of the magnet.

[0011] According to some embodiments of the present invention, the rotary jet main 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 a mounting frame; the drill rod is movably arranged on the carrying platform, and a detachable drill bit is arranged at the end of the drill rod; a grouting channel suitable for slurry circulation is formed inside the drill rod, and a plurality of grouting ports connected to the grouting channel are formed on the drill bit; the slurry conveying mechanism is connected to the grouting channel, and the slurry conveying mechanism is provided with a pressure pump, and the pressure pump 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 a 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, a drill rod is arranged 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 proposes 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 up a corresponding soil model in the model test equipment;

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

[0018] S3. Obtain mechanical monitoring data of 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 given in part in the following description and in part will be obvious from the following description, or will be learned through 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 easily understood from the description of the embodiments in conjunction with the following drawings, in which:

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

[0022] Figure 2 is a schematic structural diagram of a connection 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 assembly state of the connecting mechanism and the mounting frame according to one embodiment of the present invention;

[0024] Figure 4 It 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 spraying 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] A first sliding portion 71; a 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] Embodiments of the present invention are described in detail below, examples of which 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 only used to explain the present invention, and cannot be understood 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 influence of jet grouting to establish jet grouting piles on aeolian sand formations, but is not limited to aeolian sand formations, and can also be used to study the influence 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 body 10, a sensor 30, a pressure regulating device 40, and a jet grouting device. A soil model 20 is arranged in the box body 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 body 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 body 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 provided with a simulated tunnel lining 21 is provided to simulate the actual strata in the tunnel area, 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, so that the strata characteristics can be accurately restored and the reference value of the test results can be improved; in this embodiment, a rotary jet grouting device is used 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 a sensor 30 is used to monitor the pressure changes of the peripheral soil layer of 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, can carry out multiple grouting tests in a relatively comprehensive and sequential manner, and then simulate 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 under adjustable pressure 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 the rotary jet grouting of the soil model 20 to set horizontal rotary jet piles, and monitor the pressure changes of the surrounding soil layer of 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 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.

[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 the tunnel. 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 can be provided to apply pressure to the soil model 20 in mutually perpendicular directions to simulate the actual pressure environment conditions of the underground soil layer. Further, during the pressure regulation process, the pressure regulation accuracy can be determined and the error can be reduced based on the monitoring data of the sensor 30. In some embodiments, the pressure regulating device 40 can be constructed as a hydraulic press that is easy to control.

[0039] In some embodiments, multiple sensors 30 may be provided, and are 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 positions. In some embodiments, the sensor 30 may be configured as a pressure gauge.

[0040] According to some embodiments of the present invention, the jet spraying device includes: a mounting frame 50 and a jet spraying body; the mounting frame 50 can be arranged on the box 10 in a translational manner along a first direction, and the mounting frame 50 extends in a second direction; the jet spraying body can be arranged to move along the mounting frame 50 to selectively move to any position of the end surface of the soil model 20. The jet spraying body of this embodiment can move along the second direction relative to the mounting frame 50, and the mounting frame 50 can move along the first direction relative to the box 10, so the jet spraying body can move in a combination of the first direction and the second direction to achieve arbitrary movement within the installation plane. In some embodiments, the first direction and the second direction can be one of the height direction and the width direction of the box 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 spray 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 box 10 is provided with a first sliding portion 71, and the mounting frame 50 is provided with a second sliding portion 72 suitable for cooperating with the first sliding portion 71, and the second sliding portion 72 moves relative to the first sliding portion 71 to drive the mounting frame 50 to move relative to the box 10; the mounting frame 50 is slidably provided with a connecting mechanism 80, and one end of the connecting mechanism 80 is fixed on the rotary grouting body 60 to drive the rotary grouting body 60 to move relative to the mounting frame 50. In this embodiment, the rotary grouting body 60 is fixedly connected to the connecting mechanism 80, so the rotary grouting body 60 and the connecting mechanism 80 can move synchronously along the mounting frame 50, and the mounting frame 50 is moved relative to the box 10 through the first sliding portion 71 and the second sliding portion 72, so that the rotary grouting body 60 can move arbitrarily on the end surface of the soil model 20.

[0043] In some embodiments, the first sliding part 71 is configured as a slide rail, and the second sliding part 72 is configured as a pulley. The slide rail can be set on the side plate of the box 10, and the pulley is set at both ends of the mounting frame 50, respectively matching 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, two mounting frames 50 are provided and are arranged perpendicular to each other, and two groups of connecting mechanisms 80 are provided, which are slidably connected to one of the mounting frames 50 respectively, and are fixedly connected to the rotary spraying body 60 at the same time. Based on this, when one of the mounting frames 50 moves, it can drive the rotary spraying body 60 to move along the extension direction of the other mounting frame 50, and at the same time, the other mounting frame 50 limits the freedom of the rotary spraying body 60 to move in other directions. In this embodiment, the movement of the two groups of mounting frames 50 can drive the rotary spraying body 60 to achieve combined movement along the extension direction of the two mounting frames 50, thereby realizing the arbitrary movement of the rotary spraying body 60 on the end face of the soil model 20; the position locking of the rotary spraying body 60 can be realized by the relative stillness of the two mounting frames 50; there is no need to apply drive or brake to the rotary spraying body 60, and the structure is simpler, more efficient and more stable; at the same time, the movement process of the rotary spraying body 60 is made 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 portion can stop the movement of the mounting frame 50 relative to the box body 10 and keep it in the stop position, so as to temporarily fix the position of the rotary grouting body 60 in the first direction, so as to perform the grouting action of the fixed hole position; the limiting portion limits the movement range of the mounting frame 50 relative to the box body 10, prevents the mounting frame 50 from being separated from the box body 10, and prevents the mounting frame 50 from driving the rotary grouting body 60 beyond the soil model 20 area, so that the movement of the rotary grouting body 60 is more reliable.

[0047] According to some embodiments of the present invention, the connection mechanism 80 includes: a fixing portion 81 and a connecting arm 82; the fixing portion 81 is disposed on the rotary spray 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 approach or move away from each other; when the claws 83 approach, 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 realize the slidable connection between the rotary spray 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 claws 83 are respectively provided on opposite sides. The claws 83 are open structures. When the two claws 83 are connected, a closed surrounding structure is formed to restrict the mounting frame 50 in the middle. The claws 83 can be moved closer or farther by rotating the connecting arm 82, so that it is easy to assemble and connect with the mounting frame 50, and it is easy to slidably set the rotary 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, in order 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 and the fixing portion 81 and the claw 83 can all be relatively rotatable through bearings. In some embodiments, the claw 83 is formed with a palm portion, and is rotatably provided with at least two knuckles, and the knuckles are provided on the palm portion through bearings; when the rotary spraying body 60 of this embodiment is installed on the mounting frame 50, the claw 83 can rotate the knuckles to make it close to and surround the mounting frame 50, making it easier to clamp on the outer 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 of the claws 83 is maintained by the magnetic force generated between the magnets 84 or between the magnet 84 and the claws 83, and there is no need to set up a mechanism to limit the relative movement of the claws 83. The magnets 84 are arranged in a variety of ways and are easy to implement, so that the structure is simple and easy to operate and install. At the same time, the magnets 84 can provide a long-term and effective holding force for 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 jet main 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 arranged 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, and the pressure pump 662 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 the present embodiment conveys slurry to the drill rod 61 at a certain pressure, and 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 energy is highly concentrated and can destroy the soil. The drill bit 62 of the present 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 a high speed, while the first motor 641 drives the drill rod 61 and the drill bit 62 to approach and gradually drill into the soil model 20 by the impact force of the slurry rotating jet. Since the drill rod 61 and the drill bit 62 perform grouting by rotary jetting, the slurry will be fully stirred and mixed with the soil after being ejected, forming a columnar consolidation body, namely a rotary jet pile, in the grouting hole. The rotary jetting body 60 of the present embodiment can complete the rotary jet grouting for a fixed hole position, accurately simulate the actual construction process of the horizontal rotary jet pile, and has a high reference value for studying the application of the horizontal rotary jet pile.

[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 on 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 and 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 arbitrarily set, not limited to being set on the rotary spraying body 60, and 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 spraying body 60, and ensure the stability of 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 arranged on the mounting frame 50, and a moving channel extending in the third direction is formed on the base; the drill rod mounting portion 63 is movably arranged in the moving channel, and a drill rod 61 is arranged on the drill rod mounting portion 63 and is suitable for driving the drill rod mounting portion 63 to move in the third direction. The third direction of this embodiment is a direction perpendicular to the end face of the soil model 20, the base is slidably arranged on the mounting frame 50 along the second direction, the drill rod mounting portion 63 is slidably connected to the base along the third direction, and the drill rod 61 is arranged on the drill rod mounting portion 63, so that the drill rod 61 can be moved relative to the base to drive the drill bit 62 to move closer to or farther from the soil model 20. The drill rod 61 of this embodiment can accurately move to the soil model 20 for drilling through the superposition of 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 along the third direction is formed on one side of the drill rod mounting portion 63, and 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 to move through a gear rack mechanism combination to achieve the approach or distance of the drill rod 61 and the drill bit 62 relative to the soil model 20. Since the gear rack transmission mechanism can provide a large driving force and bear a large reverse force at the same time, it can provide a driving force sufficient to destroy the soil for the drill rod 61 to drill, ensuring that the drill rod 61 is stably grouted and penetrated.

[0054] According to some embodiments of the present invention, a rotating disk 653 is rotatably provided on the drill rod mounting portion 63, and 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, and a second motor 651 is provided on the drill rod mounting portion 63, and a second driving gear 652 meshing with the transmission gear 654 is provided at the output end of the second motor 651. In this embodiment, the drill rod 61 is driven to rotate by the second motor 651 driving the gear combination, and the rotating disk 653 is provided to facilitate the rotatable connection between the drill rod 61 and the drill rod mounting portion 63, so that the drill rod 61 is connected to 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, and the box legs 90 are suitable for adjusting the 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 also includes a control unit, which is suitable for receiving the simulated tunnel lining 21 peripheral soil pressure data monitored in real time by the sensor 30, and is suitable for controlling the rotary jet device to perform rotary jet grouting. Specifically, the control unit includes a computer integrated module 67 arranged in the rotary jet main body 60, and 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 output rotation. Further, the computer integrated module 67 is provided with a Bluetooth module, and the Bluetooth module is suitable for remotely receiving the command signal of the control unit and transmitting it to the computer integrated module 67 to send to the first motor 641 and the second motor 651. In this embodiment, the operating parameters of the first motor 641 and the second motor 651 can be set by the control unit, and an action instruction can be issued to them to drive the drill rod 61 to rotate and drill; during the rotary jet grouting process, the control unit can receive and record the pressure data monitored in real time by each sensor 30 for analyzing the influence of horizontal rotary jet grouting. In addition, the control unit is suitable for inputting and recording the basic parameters of the soil model 20, and automatically calculating the grouting parameters and the operating parameters of the first motor 641 and the second motor 651 according to the input parameters. This embodiment can improve the degree of automation of the model test equipment by setting the control unit, so that the test process is based on data visualization, which is more conducive to grasping the test process and improving the restoration of the actual construction process, thereby improving the reference value of the test. In some embodiments, the control unit can be constructed as a central control computer to facilitate the subsequent analysis process.

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

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

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

[0060] S3. Acquire mechanical monitoring data of the corresponding sensor 30 of the simulated tunnel lining 21, 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 establishing a model can repeat the test, reduce errors, and improve the reliability of the test results.

[0062] In S1, the target parameters of the soil model 20 are determined according to the environmental parameters of the target area, so as to improve 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 method for using the model test equipment specifically includes: measuring the actual soil layer cover thickness, soil density, soil pressure, and porosity of the tunnel area to be built, establishing a soil model 20 based on a similarity principle, and applying pressure to the soil model 20 using a pressure regulating device 40. In the process of establishing the soil model 20 and adjusting the soil pressure, the data monitored by the sensor 30 can be used to determine in real time whether the soil pressure is adjusted to the target value, so that the pressure parameters of the soil model 20 can be visualized during the establishment process, and can be adjusted in real time based on evidence, without the need for additional measurement and repeated pressure adjustment operations, which can improve the efficiency of model establishment.

[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 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, then (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, internal friction angle, etc., 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 layer cover thickness, soil pressure, soil density, and porosity of the soil model 20;

[0068] S2.2, setting the drilling depth, drilling area, drilling pressure and rotation 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; setting the grouting pressure of the pressure pump 662 according to the calculation result of S2.1, and performing a slurry test spray to detect the smoothness of slurry transportation;

[0069] S2.3, determine the various hole positions for horizontal drilling on the soil model 20, move the rotary jet grouting device to the hole positions one by one and start rotary 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 layer thickness is recorded as h, the soil density is recorded as γ, the grouting pressure is recorded as P, and the grouting volume per linear meter is recorded 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 may be 1.3;

[0073] Grouting volume per linear 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 depth of the borehole; in some embodiments, k2=0.6-0.7;

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

[0076] This embodiment determines the grouting parameters through 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 above-mentioned model test equipment specifically includes: deriving pressure data and drawing time variation curves of contact pressure and tangential stress according to the monitored pressure data, so as to analyze the pressure variation of the simulated tunnel lining 21 during the process of grouting to form jet grouting piles; judging whether there are dangers or hidden dangers in the grouting process according to whether the pressure value exceeds the standard range, and predicting the feasibility of high-pressure jet grouting during the actual construction process. In step S3 of this embodiment, if the pressure value exceeds the standard range, it indicates that the construction of horizontal jet grouting piles is in danger of collapse of aeolian sand strata, and is not feasible for practical application.

[0079] This embodiment uses pressure data to determine the stability of the soil model during the construction of simulated jet grouting piles, and then infers the stability of the actual stratum environment during the process of establishing jet grouting piles under similar conditions. Since the destruction and deformation of the stratum environment are the result of force action, pressure is the most direct aspect that can reflect the impact on the soil, so the measurement results of this embodiment are highly reliable; at the same time, pressure data has the characteristics of obvious changes, convenient establishment of standard ranges, convenient measurement, and convenient comparison, which can reduce the test burden and reduce judgment errors.

[0080] In the description of the present invention, it is to 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 orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0081] In the description of the present invention, "first feature" or "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 that the first and second features are directly in contact with each other, or may include that the first and second features are not in direct contact with each other but are in contact with each other via another feature therebetween.

[0084] In the description of the present invention, “on”, “above” and “over” a first feature from a second feature include 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] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0086] Although 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 present invention, and that the scope of the present 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, the sensor being disposed in the soil model and being adapted to monitor the pressure around the simulated tunnel lining; A pressure regulating device, the pressure regulating device is arranged in the box, and the pressure regulating device is suitable for adjusting and applying pressure to the soil model; A jet grouting device is provided with a drill bit suitable for jet grouting the soil model. The jet grouting device is movably arranged on the box body to selectively perform jet grouting on the soil model around the simulated tunnel lining.

2. The model test equipment according to claim 1, characterized in that: The rotary spraying device comprises: A mounting frame, the mounting frame is disposed on the box body so as to be translatably movable along a first direction, and the mounting frame extends in a second direction; The rotary grouting body can be movably arranged along the mounting frame so as to be selectively moved to any position of the end surface of the soil model.

3. The model test equipment according to claim 2, 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 spray body to drive the rotary spray body to move relative to the mounting frame.

4. The model test equipment according to claim 3, characterized in that: 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.

5. The model test equipment according to claim 4, characterized in that: The connecting mechanism comprises: A fixing part, the fixing part is 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 of at least two pieces, and the connecting arms rotate to allow the claws to selectively move closer to or farther from each other; when the claws move closer to each other, they cooperate to surround the mounting frame and are suitable for sliding relative to the mounting frame.

6. The model test equipment according to claim 5, 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.

7. The model test equipment according to claim 2, characterized in that: The rotary spraying body comprises: A carrying platform, the carrying platform is movably arranged on the mounting frame; A drill rod, the drill rod is movably arranged on the carrying platform, and a detachable drill bit is arranged 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; A slurry delivery mechanism, the slurry delivery mechanism is communicated with the grouting channel, the slurry delivery mechanism is provided with a pressure pump, and the pressure pump is suitable for delivering slurry to the drill bit and adjusting the grouting pressure; A first motor and a second motor, wherein the first motor and the second motor are arranged on the carrying platform, the first motor is suitable for driving the drill rod away from or close to the soil model; and the second motor is suitable for driving the drill rod to rotate.

8. The model test equipment according to claim 7, characterized in that: The carrying platform comprises: A base, the base is movably disposed on the mounting frame, and a moving channel extending in a third direction is formed on the base; 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.

9. The model test equipment according to claim 8, 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.

10. The model test equipment according to claim 8, 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 a second driving gear meshing with the transmission gear is arranged at the output end of the second motor.

11. A method for using the model test equipment according to any one of claims 1 to 10, 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 of 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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