A model test device for simulating foundation pit excavation based on 3D printing transparent soil

Abstract

The present application relates to the technical fields of model test of 3D printing transparent soil, and discloses a model test device for simulating foundation pit excavation based on 3D printing transparent soil, which comprises a test base, a model groove main body, a control and analysis table, a track system, a 3D printing transparent soil preparation system, a vacuum saturation system and a simulated excavation system, the test base is a horizontally arranged rectangular base, and the upper surface of the test base is sequentially provided with the track system, the 3D printing transparent soil preparation system, the vacuum saturation system and the simulated excavation system from front to back. The model test device for simulating foundation pit excavation based on 3D printing transparent soil and the using method thereof can collect test data through the CCD camera and the laser which can freely adjust the position and the angle, compared with the traditional method for simulating foundation pit excavation by using sensors to collect data, the present application can more comprehensively and accurately reflect the response of the continuous deformation of the soil body around the foundation pit in the process of the foundation pit excavation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of 3D printed transparent soil model test, in particular to a model test device for simulating foundation pit excavation based on 3D printed transparent soil. BACKGROUND

[0002] Since the 21st century, China's economy has been booming, and the country's comprehensive national strength has been continuously enhanced. In order to meet the growing demand of urban population, China has vigorously developed infrastructure construction and urban construction. However, the problem of urban land resource supply and demand contradiction is increasingly prominent. In order to solve this problem, it is necessary to increase the development of underground space and improve the intensification degree of land use. Under this trend, deep foundation pit engineering has been widely used. However, deep foundation pit engineering also faces some new challenges, including the problems of foundation pit deformation and instability caused by foundation pit excavation.

[0003] In order to ensure the safety and stability of foundation pit and surrounding buildings, many scholars have carried out a large number of simulation tests of foundation pit excavation. In these tests, indoor soil model test is a traditional method which has been widely used in geotechnical engineering field. However, most of the traditional methods need to bury sensors in soil or install them on simulated continuous walls, which will be disturbed by factors such as sensor stiffness and size, and cannot directly observe the internal deformation of soil.

[0004] In order to reveal the internal deformation of soil, transparent soil model test technology is proposed and widely used. The basic principle of transparent soil technology is to use transparent soil material and digital image processing technology to observe the internal change process of soil. At the same time, with the progress of 3D printing technology, particle materials are no longer limited to computer simulation, but can be printed into any shape of particles through 3D printer. This makes us develop from the theoretical segment to the precise test segment in the previous study of soil particles. Therefore, 3D printed transparent soil particle material can be used to control the shape and pore distribution of soil particles.

[0005] Therefore, it is necessary to develop a device and its use method which can realize the automation, intelligence, integration and high precision of 3D printed transparent soil particle equipment, transparent soil preparation equipment and simulation foundation pit excavation equipment. SUMMARY

[0006] (I) Technical problems solved

[0007] In view of the deficiencies of the prior art, the model test device for simulating foundation pit excavation based on 3D printed transparent soil and the use method thereof have the advantages that the 3D printed transparent soil particle equipment, the transparent soil preparation equipment, the simulated foundation pit excavation equipment automation, the intelligentization, the integration and the high precision can be realized, the particle material is no longer limited to the simulation in the computer, but the particle of any shape can be printed out through the 3D printer, and the problem that the research on the soil particle is developed from the theoretical stage to the accurate test stage is solved.

[0008] (II) Technical scheme

[0009] In order to realize the above-mentioned purpose of realizing the 3D printed transparent soil particle equipment, the transparent soil preparation equipment, the simulated foundation pit excavation equipment automation, the intelligentization, the integration and the high precision, the present application provides the following technical scheme: a model test device for simulating foundation pit excavation based on 3D printed transparent soil, comprising a test base, a main model groove, a control and analysis table, a track system, a transparent soil preparation system, a vacuum saturation system and a simulated excavation system, the test base is a horizontally arranged rectangular base, and the upper surface of the test base is sequentially provided with the track system, the transparent soil preparation system, the vacuum saturation system and the simulated excavation system from front to back.

[0010] The track system comprises a model groove track and a pulley trolley.

[0011] The transparent soil preparation system comprises a first stand, a first platform, a storage box, a 3D printer, a slide, a mechanical arm and a main stirrer.

[0012] The vacuum saturation system comprises a second stand, a second platform, a first telescopic straight rod, a vacuum cover plate, a flexible pipe, a vacuum pump, an air valve and an air pressure gauge.

[0013] The simulated excavation system comprises a third stand, a rectangular frame, a horizontal longitudinal beam, a second telescopic straight rod, a spherical hinge, a grab bucket, a sliding device, a helium-neon laser and a CCD camera.

[0014] The top of the test base is fixedly provided with two model groove tracks, the top of the two model groove tracks is slidably connected with a pulley trolley, the bottom of the pulley trolley is provided with two track shafts, and the two ends of the two track shafts are rotatably connected with pulley bodies which are slidably connected with the model groove tracks, and the bottom of the main model groove is connected with the top of the pulley trolley.

[0015] The main model groove adopts transparent organic glass, the main model groove adopts the rectangular box with the upper end opening, the U-shaped clamping groove, the underground continuous wall simulation board and the square column-shaped movable panel are installed in the main model groove, the U-shaped clamping groove is arranged on the inner side of the two side walls of the main model groove, the length direction of the two side walls of the main model groove is parallel with the length direction of the model groove track, the underground continuous wall simulation board and the square column-shaped movable panel are movably connected on the U-shaped clamping groove, the square column-shaped movable panel divides the main model groove into two areas, which are a first model groove area and a second model groove area, the second model groove area is the model groove area in the moving direction of the main model groove, and the first model groove area is another area of the main model groove.

[0016] The top of the test base is fixedly installed with four first columns, the top of the four first columns is fixedly installed with a first platform, the top of the first platform is installed with a storage box, the side of the storage box is installed with a 3D printer arrangement, the 3D printer is connected with the storage box through a slide, the top of the test base and the bottom of the first platform are fixedly installed with a mechanical arm, and the end of the mechanical arm is installed with a main stirrer.

[0017] The inside of the storage box is divided into two compartments, the two compartments are a liquid compartment and a particle compartment, the bottom of the liquid compartment and the particle compartment is provided with a discharge port, the discharge port is provided with an electromagnetic valve, and the inside of the liquid compartment is provided with two small stirrers.

[0018] Preferably, the top of the test base is fixedly installed with four second columns, the top of the four second columns is fixedly installed with a second platform, the inside of the second platform is fixedly installed with a first telescopic straight rod, the bottom of the first telescopic straight rod is fixedly installed with a vacuum cover plate, the inside of the first telescopic straight rod is installed with a flexible pipe, the top of the second platform is fixedly installed with a vacuum pump, the second platform is fixedly installed with an air valve connected with the flexible pipe, the vacuum pump is connected with the air valve through the flexible pipe, and the second platform is installed with an air pressure gauge connected with the air valve.

[0019] Preferably, the top of the test base is fixedly installed with four third columns, the top of the four third columns is installed with a rectangular frame, the rectangular frame includes a first cross beam, a second cross beam, a first longitudinal beam and a second longitudinal beam, the length direction of the first cross beam and the second cross beam is parallel with the length direction of the model groove track, the length direction of the first longitudinal beam and the second longitudinal beam is perpendicular to the length direction of the model groove track, the first longitudinal beam is away from the vacuum saturation system, the second longitudinal beam is close to the vacuum saturation system, the outer surface of the first longitudinal beam is installed with a first sliding rail, the inner and outer surfaces of the first cross beam and the second cross beam are installed with second sliding rails, and a horizontal longitudinal beam is arranged between the first cross beam and the second cross beam.

[0020] Preferably, the two ends of the transverse beam are provided with first sliding devices and second sliding devices, the first sliding devices and the second sliding devices are in sliding connection with the second sliding rails on the inner sides of the first beam and the second beam, the lower surface of the transverse beam is provided with a third sliding rail, the third sliding rail on the lower surface of the transverse beam is in sliding connection with a third sliding device, the first beam and the second beam are provided with fourth sliding devices and fifth sliding devices and sixth sliding devices through the first sliding rails on the outer sides of the first beam and the second beam, the bottoms of the first sliding devices, the second sliding devices, the third sliding device, the fourth sliding devices, the fifth sliding devices and the sixth sliding devices are fixedly provided with second telescopic straight rods, the second telescopic straight rods at the bottoms of the third sliding devices are connected with a grab bucket through a ball hinge, the bottoms of the second telescopic straight rods are fixedly provided with helium-neon lasers, and the bottoms of the second telescopic straight rods on the left and right sides are fixedly provided with CCD cameras.

[0021] Preferably, the bottoms of the first column, the second column and the third column are fixed with the test base through first nuts, and the tops of the first column, the second column and the third column are connected with the first platform, the second platform and the rectangular frame through second nuts.

[0022] A use method of a model test device for simulating foundation pit excavation based on 3D printed transparent soil, comprising the following steps:

[0023] Step one: install and debug the control analysis table, the track system, the transparent soil preparation system, the vacuum saturation system and the simulation excavation system;

[0024] Step two: control the 3D printer to print particle materials through the control analysis table, add the particle materials into the particle bin through the slide, add phenyl methyl silicone oil and No. 15 white oil into the liquid bin at a mass ratio of 2:5, and uniformly stir the liquid materials through the small stirrer;

[0025] Step three: arrange the square column-shaped movable panel in the inside of the main model groove through the U-shaped clamping slot, control the main model groove to move to the right below the storage box through the control analysis table, and control the main stirrer to move to the first model groove area through the mechanical arm;

[0026] Step four: input the transparent soil material adding amount through the control analysis table, open the electromagnetic valves at the main stirrer and the discharge port, make the transparent soil material flow into the inside of the first model groove area, and uniformly stir the transparent soil material in the first model groove area through the main stirrer;

[0027] Step five: when the adding amount of the transparent soil material meets the requirement, close the electromagnetic valves and the main stirrer, control the main stirrer to leave the main model groove through the mechanical arm, and arrange the underground continuous wall simulation plate in the first model groove area through the U-shaped clamping slot;

[0028] Step six: move the main model tank to the position directly below the vacuum cover plate by operating the analysis platform, lower the vacuum cover plate and tightly seal it on the excavated main model tank, connect the vacuum pump to the air valve through the flexible pipe, turn on the vacuum pump and the air valve, and turn off the vacuum pump and the air valve after the air pressure gauge reading meets the requirements;

[0029] Step seven: move the flexible pipe away from the air valve, turn on the air valve, and move the vacuum cover plate up and separate it from the main model tank;

[0030] Step eight: move the main model tank to the designated position of the simulated excavation system by operating the analysis platform, adjust the position and angle of the helium-neon laser and CCD camera on the rectangular frame by operating the analysis platform, and turn on the CCD camera and helium-neon laser after adjusting the CCD camera and helium-neon laser.

[0031] Step nine: control the grab on the rectangular frame to grab the first square column-shaped movable panel by operating the analysis platform, and the first layer of excavated soil flows into the interior of the second model tank area, while the grab on the rectangular frame is controlled by the control analysis platform to place the first layer of excavated soil into the interior of the second model tank area.

[0032] Step ten: after the first layer of soil is excavated, the grab on the rectangular frame is controlled by the analysis platform to grab the second square column-shaped movable panel, and step nine is repeated until the specified depth is excavated.

[0033] Step eleven: the CCD camera continuously takes pictures and sends the collected information to the control analysis platform, and the control analysis platform analyzes and processes the collected information.

[0034] Step twelve: after the simulated excavation test is completed, record the test results, remove the main model tank, and remove the transparent soil material.

[0035] (Three) beneficial effects

[0036] Compared with the prior art, the present application provides a model test device for simulating foundation pit excavation based on 3D printed transparent soil, which has the following beneficial effects:

[0037] 1. The model test device for simulating foundation pit excavation based on 3D printed transparent soil collects test data through CCD cameras and lasers with adjustable position and angle, which can more comprehensively and accurately reflect the response of foundation pit stress and foundation pit deformation during foundation pit excavation compared with the traditional simulation method of using strain gauges to collect data.

[0038] 2. The model test device for simulating foundation pit excavation based on 3D printed transparent soil, which uses transparent soil material to replace traditional sand for simulating foundation pit excavation, and can more directly observe the deformation of the internal soil during the foundation pit excavation process, rather than only observing the deformation of the peripheral soil.

[0039] 3. The model test device for simulating foundation pit excavation based on 3D printed transparent soil and the use method thereof, which can remove the symmetric face retaining unit before excavating each layer of soil by using multiple square column-shaped movable panels as retaining units, and can clearly determine the excavation depth of the foundation pit by the method of unloading soil from the symmetric face of the foundation pit, and each layer of excavated soil does not affect the unexcavated soil, so that the operation is convenient, and the work load of unloading soil during the foundation pit excavation is greatly reduced.

[0040] 4. The model test device for simulating foundation pit excavation based on 3D printed transparent soil, which uses an automatic track to integrate the material stirring, vacuum saturation and simulation excavation process during the test process, improves the functionality and utilization rate of the test device, and reduces the transportation work load of the test model.

[0041] 5. The model test device for simulating foundation pit excavation based on 3D printed transparent soil, which considers the dismounting property through component design, so that it is more convenient to transport, install and maintain, and the operation is simple, and the test efficiency is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 It is a schematic diagram of the overall structure of the test device of the present application;

[0043] Figure 2 It is a top view of the transparent soil preparation system of the present application;

[0044] Figure 3 It is a schematic diagram of the vacuum saturation system of the present application;

[0045] Figure 4 It is a side view of the vacuum saturation system of the present application;

[0046] Figure 5 It is a general schematic diagram of the simulation excavation system of the present application;

[0047] Figure 6 It is a first perspective view of the main model groove and the pulley trolley of the present application;

[0048] Figure 7 It is a schematic diagram of the grab, spherical hinge, telescopic rod and sliding device of the present application;

[0049] Figure 8 It is a schematic diagram of the underground continuous wall simulation plate and the square column-shaped movable panel of the present application.

[0050] In the figure: 1, test base; 2, main model groove; 201, U-shaped clamping groove; 202, underground continuous wall simulation board; 203, square column-shaped movable panel; 204, first model groove area; 205, second model groove area; 3, control analysis table; 4, track system; 401, model groove track; 402, pulley trolley; 4021, track wheel shaft; 4022, pulley body; 5, transparent soil preparation system; 501, first stand; 502, first platform; 503, storage box; 5031, discharge port; 5032, electromagnetic valve; 5033, liquid bin; 50331, small stirrer; 5034, particle bin; 504, 3D printer; 505, slide; 506, mechanical arm; 507, main stirrer; 6, vacuum saturation system; 601, second stand; 602, second platform; 603, first telescopic straight rod; 604, vacuum cover plate; 605, flexible pipe; 606, vacuum pump; 607, air valve; 608, air pressure gauge; 7, simulated excavation system; 701, third stand; 702, rectangular frame; 7021, first cross beam; 7022, second cross beam; 7023, first longitudinal beam; 7024, second longitudinal beam; 703, transverse longitudinal beam; 704, second telescopic straight rod; 705, spherical hinge; 706, grab bucket; 7071, first sliding device; 7072, second sliding device; 7073, third sliding device; 7074, fourth sliding device; 7075, fifth sliding device; 7076, sixth sliding device; 708, helium-neon laser; 709, CCD camera. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0052] Please refer to Figures 1-8 A model test device for simulating foundation pit excavation based on 3D-printed transparent soil, comprising a test base 1, a main model groove 2, a control analysis table 3, a track system 4, a transparent soil preparation system 5, a vacuum saturation system 6, and a simulated excavation system 7. The test base 1 is a horizontally arranged rectangular base, and the upper surface of the test base 1 is sequentially provided with the track system 4, the transparent soil preparation system 5, the vacuum saturation system 6, and the simulated excavation system 7 from front to back.

[0053] The track system 4 comprises a model groove track 401 and a pulley trolley 402.

[0054] The transparent soil preparation system 5 comprises a first stand 501, a first platform 502, a storage box 503, a 3D printer 504, a slide 505, a mechanical arm 506 and a main mixer 507.

[0055] The vacuum saturation system 6 comprises a second stand 601, a second platform 602, a first telescopic straight rod 603, a vacuum cover plate 604, a flexible pipe 605, a vacuum pump 606, an air valve 607 and an air pressure gauge 608.

[0056] The simulated excavation system 7 comprises a third stand 701, a rectangular frame 702, a horizontal longitudinal beam 703, a second telescopic straight rod 704, a spherical hinge 705, a grab bucket 706, a sliding device 707, a helium-neon laser 708 and a CCD camera 709.

[0057] In the case implementation, the top of the test base 1 is fixedly provided with two model groove tracks 401, the top of the two model groove tracks 401 is slidably connected with a pulley trolley 402, the bottom of the pulley trolley 402 is provided with two track axles 4021, the two ends of the two track axles 4021 are rotatably connected with pulley bodies 4022 which are slidably connected with the model groove tracks 401, and the bottom of the main model groove 2 is connected with the top of the pulley trolley 402.

[0058] By using the automatic track, the material mixing, vacuum saturation and simulated excavation process in the test process are integrated, the functionality and utilization rate of the test device are improved, and the transportation workload of the test model is reduced.

[0059] In the case implementation, the main model groove 2 is made of transparent organic glass, the main model groove 2 is a rectangular box with an open top, the main model groove 2 is internally provided with a U-shaped clamping groove 201, an underground continuous wall simulation plate 202 and a square column-shaped movable panel 203, the U-shaped clamping groove 201 is arranged on the inner side of the two side walls of the main model groove 2, the length direction of the two side walls of the main model groove 2 is parallel to the length direction of the model groove track 401, the underground continuous wall simulation plate 202 and the square column-shaped movable panel 203 are movably connected to the U-shaped clamping groove 201, the square column-shaped movable panel 203 divides the main model groove 2 into two areas, i.e., a first model groove area 204 and a second model groove area 205, the second model groove area 205 is the model groove area in the moving direction of the main model groove 2, and the first model groove area 204 is another area of the main model groove 2.

[0060] The four side walls of the main model groove 2 are provided with scale lines, and the underground continuous wall simulation board 202 and the square column-shaped movable panel 203 are made of transparent organic glass, and the square column-shaped movable panel 203 is a plurality of square column-shaped movable panels 203, and the plurality of square column-shaped movable panels 203 are sequentially defined as the first square column-shaped movable panel 203, the second square column-shaped movable panel 203, and the like from top to bottom, the first layer of excavated soil is from the ground surface to the bottom of the first square column-shaped movable panel 203, the second layer of excavated soil is from the bottom of the first square column-shaped movable panel 203 to the bottom of the second square column-shaped movable panel 203, and the like, each excavated soil layer is defined, and the plurality of square column-shaped movable panels 203 are used as soil retaining units, so that the symmetric face soil retaining unit can be removed in advance before excavating each layer of soil, the foundation pit is excavated by the method of unloading soil to the foundation pit excavation symmetric face, compared with the traditional downward soil excavation method, the excavation depth of the foundation pit can be determined, each layer of excavated soil does not affect the unexcavated soil layer, the operation is convenient, and the work amount of unloading soil for foundation pit excavation is greatly reduced.

[0061] In the case implementation, the top of the test base 1 is fixedly installed with four first columns 501, the top of the four first columns 501 is fixedly installed with a first platform 502, the top of the first platform 502 is installed with a storage box 503, the side of the storage box 503 is installed with a 3D printer arrangement 504, the 3D printer 504 is connected with the storage box 503 through a slide 505, the top of the test base 1 and the bottom of the first platform 502 are fixedly installed with a mechanical arm 506, the end of the mechanical arm 506 is installed with a main stirrer 507, the inside of the storage box 503 is divided into two compartments, the two compartments are a liquid compartment 5033 and a particle compartment 5034, the bottom of the liquid compartment 5033 and the particle compartment 5034 is provided with a discharge port 5031, the discharge port 5031 is provided with a solenoid valve 5032, and the inside of the liquid compartment 5033 is provided with two small stirrers 50331.

[0062] The liquid compartment 5033 is close to the vacuum saturation system 6, the particle compartment 5034 is away from the vacuum saturation system 6, the 3D printer 504 is Formlabs Form2 SLA 3D, and Formlabs transparent photosensitive resin is used as raw material to print particle materials.

[0063] In the case implementation, the top of the test base 1 is fixedly installed with four second columns 601, the top of the four second columns 601 is fixedly installed with a second platform 602, the inside of the second platform 602 is fixedly installed with a first telescopic straight rod 603, the bottom of the first telescopic straight rod 603 is fixedly installed with a vacuum cover plate 604, the inside of the first telescopic straight rod 603 is installed with a flexible pipe 605, the top of the second platform 602 is fixedly installed with a vacuum pump 606, the second platform 602 is fixedly installed with an air valve 607 connected with the flexible pipe 605, the vacuum pump 606 is connected with the air valve 607 through the flexible pipe 605, the second platform 602 is installed with an air pressure gauge 608 connected with the air valve 607, and the vacuum cover plate 604 is connected with the air valve 607 on the second platform 602 through the flexible pipe 605.

[0064] When the vacuum cover plate 604 is capped on the upper port of the main model groove 2, sealing oil is coated between the vacuum cover plate 604 and the main model groove 2, a rubber ring is arranged on the inner wall of the upper end of the main model groove 2, and the vacuum cover plate 604 is capped on the main model groove 2 through the rubber ring, so that the main model groove 2 is sealed.

[0065] In the case implementation, the top of the test base 1 is fixedly installed with four third columns 701, the top of the four third columns 701 is installed with a rectangular frame 702, the rectangular frame 702 includes a first cross beam 7021, a second cross beam 7022, a first longitudinal beam 7023 and a second longitudinal beam 7024, the length direction of the first cross beam 7021 and the second cross beam 7022 is parallel to the length direction of the model groove track 401, the length direction of the first longitudinal beam 7023 and the second longitudinal beam 7024 is perpendicular to the length direction of the model groove track 401, the first longitudinal beam 7023 is away from the vacuum saturation system 6, the second longitudinal beam 7024 is close to the vacuum saturation system 6, the outer side surface of the first longitudinal beam 7023 is installed with a first sliding rail, the inner and outer side surfaces of the first cross beam 7021 and the second cross beam 7022 are installed with a second sliding rail, a cross longitudinal beam 703 is arranged between the first cross beam 7021 and the second cross beam 7022, the cross longitudinal beam 703 is installed with a first sliding device 7071 and a second sliding device 7072 at both ends, the first sliding device 7071 and the second sliding device 7072 are slidably connected with the second sliding rail on the inner side of the first cross beam 7021 and the second cross beam 7022, the lower surface of the cross longitudinal beam 703 is installed with a third sliding rail, the third sliding rail on the lower surface of the cross longitudinal beam 703 is slidably connected with a third sliding device 7073, the first longitudinal beam 7023 is slidably connected with a fourth sliding device 7074 through the first sliding rail on the outer side surface, the second sliding rail on the outer side of the first cross beam 7021 and the second cross beam 7022 is slidably connected with a fifth sliding device 7075 and a sixth sliding device 7076, the bottom of the first sliding device 7071, the second sliding device 7072, the third sliding device 7073, the fourth sliding device 7074, the fifth sliding device 7075 and the sixth sliding device 7076 is fixedly installed with a second telescopic straight rod 704, the second telescopic straight rod 704 at the bottom of the third sliding device 7073 is connected with a grab bucket 706 through a ball hinge 705, the bottom of the front side second telescopic straight rod 704 is fixedly installed with a helium-neon laser 708, the bottom of the left and right side second telescopic straight rod 704 is fixedly installed with a CCD camera 709.

[0066] The CCD camera 709 and the laser 708 can freely adjust the position and angle to collect test data, compared with the traditional analog foundation pit excavation method using strain gauges to collect data, the present application can more comprehensively and accurately reflect the response of the foundation pit stress and the foundation pit deformation in the foundation pit excavation process.

[0067] In the case implementation, the bottom of the first column 501, the second column 601 and the third column 701 is fixed with the test base 1 through the first nut, the top of the first column 501, the second column 601 and the third column 701 is connected with the first platform 502, the second platform 602 and the rectangular frame 702 through the second nut,

[0068] Through the detachable first column 501, second column 601 and third column 701, the component design takes into account the detachability, making it easier to transport, install and maintain, and the operation is simple, greatly improving the test efficiency.

[0069] In implementation, the following steps are taken:

[0070] Step one: install and debug the control analysis platform 3, track system 4, transparent soil preparation system 5, vacuum saturation system 6 and simulated excavation system 7;

[0071] Step two: control the 3D printer 504 to print granular material through the control analysis platform 3, and add the granular material to the granular bin 5034 through the chute 505, add phenylmethyl silicone oil and No. 15 white oil to the liquid bin 5033 at a mass ratio of 2:5, and uniformly stir the liquid material through the small stirrer 50331;

[0072] Step three: arrange the square column-shaped movable panel 203 inside the main model groove 2 through the U-shaped clamping slot 201, move the main model groove 2 to be directly below the storage bin 503 through the control analysis platform 3, and control the main stirrer 507 to move to the first model groove area 204 through the mechanical arm 506;

[0073] Step four: input the transparent soil material addition amount through the control analysis platform 3, open the electromagnetic valve 5032 at the main stirrer 507 and the discharge port 5031, and the transparent soil material flows into the inside of the first model groove area 204, and the main stirrer 507 uniformly stirs the transparent soil material in the first model groove area 204;

[0074] Step five: when the addition amount of transparent soil material meets the requirements, close the electromagnetic valve 5032 and the main stirrer 507, control the main stirrer 507 to leave the main model groove 2 through the mechanical arm 506, and arrange the underground continuous wall simulation plate 202 in the first model groove area 204 through the U-shaped clamping slot 201;

[0075] Step six: move the main model groove 2 to be directly below the vacuum cover plate 604 through the control analysis platform 3, and the vacuum cover plate 604 moves down and tightly covers the excavated main model groove 2, connect the vacuum pump 606 to the air valve 607 through the flexible pipe 605, open the vacuum pump 606 and the air valve 607, and close the vacuum pump 606 and the air valve 607 when the air pressure gauge 608 reading meets the requirements;

[0076] Step seven: move the flexible pipe 605 away from the air valve 607, open the air valve 607, and the vacuum cover plate 604 moves up and separates from the main model groove 2;

[0077] Step eight: control the main model tank 2 to move to the designated position of the simulated excavation system 7 by operating the analysis platform 3, adjust the positions and angles of the helium-neon lasers 708 and the CCD cameras 709 on the rectangular frame 702 by operating the analysis platform 3, and turn on the CCD cameras 709 and the helium-neon lasers 708 after the CCD cameras 709 and the helium-neon lasers 708 are adjusted;

[0078] Step nine: control the grab bucket 706 on the rectangular frame 702 to grab the first square column-shaped movable panel 203 by operating the analysis platform 3, and the first layer of excavated soil flows into the inside of the second model tank area 205, and at the same time, control the grab bucket 706 on the rectangular frame 702 to grab the first layer of excavated soil by operating the analysis platform 3 and put it into the inside of the second model tank area 205;

[0079] Step ten: after the first layer of soil is excavated, control the grab bucket 706 on the rectangular frame 702 to grab the second square column-shaped movable panel 203 by operating the analysis platform 3, and repeat step nine until the specified depth is excavated;

[0080] Step eleven: the CCD cameras 709 continuously take pictures and send the collected information to the operation and analysis platform 3, and the operation and analysis platform 3 analyzes and processes the collected information;

[0081] Step twelve: after the simulated excavation test is completed, record the test results, remove the main model tank 2, and remove the transparent soil material.

[0082] In summary, the model test device and the use method thereof based on the 3D printed transparent soil for simulating foundation pit excavation, by the CCD cameras 709 and the lasers 708 with adjustable positions and angles, can collect test data, compared with the traditional simulation method of foundation pit excavation using strain gauges to collect data, the present application can more comprehensively and accurately reflect the response of the foundation pit stress and the foundation pit deformation in the process of foundation pit excavation, and the transparent soil material is used to replace the traditional sand soil for simulating foundation pit excavation, compared with the traditional simulation method of foundation pit excavation, the present application can more directly observe the deformation of the internal soil in the process of foundation pit excavation, and is not limited to observing the deformation of the peripheral soil.

[0083] And, by adopting the plurality of square column movable panels 203 as the retaining unit, the symmetric surface retaining unit can be removed in advance before excavating each layer of soil, and the foundation pit is excavated by the method of unloading soil to the symmetric surface of the foundation pit excavation, compared with the traditional method of unloading soil by digging down, the present application can determine the depth of the foundation pit excavation, and each layer of excavated soil does not affect the unexcavated soil layer, which is convenient to operate, greatly reduces the workload of unloading soil for foundation pit excavation, adopts automatic track, integrates material mixing, vacuum saturation and simulation excavation process during the test process, improves the functionality and utilization rate of the test device, reduces the transportation workload of the test model, the component design considers the disassembly, which makes it easier to transport, install and maintain, and the operation is simple, which greatly improves the test efficiency.

[0084] It should be noted that, in this document, the terms such as first and second are used merely to distinguish one entity or operation from another, and do not necessarily require or imply that these entities or operations exist in any such actual relationship or order. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or equipment including the element.

[0085] Although the embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A model test device for simulating foundation pit excavation based on 3D printed transparent soil, comprising a test base (1), a main model groove (2), a control and analysis table (3), a track system (4), a transparent soil preparation system (5), a vacuum saturation system (6) and a simulated excavation system (7), characterized in that: The test base (1) is a horizontally arranged rectangular base, and the upper surface of the test base (1) is sequentially provided from front to back with a track system (4), a transparent soil preparation system (5), a vacuum saturation system (6) and a simulated excavation system (7); The track system (4) comprises a model groove track (401) and a pulley trolley (402); The transparent soil preparation system (5) comprises a first stand (501), a first platform (502), a storage box (503), a 3D printer (504), a slide (505), a mechanical arm (506) and a main mixer (507); The vacuum saturation system (6) comprises a second stand (601), a second platform (602), a first telescopic straight rod (603), a vacuum cover plate (604), a flexible pipe (605), a vacuum pump (606), an air valve (607) and an air pressure gauge (608); The simulated excavation system (7) comprises a third stand (701), a rectangular frame (702), a horizontal longitudinal beam (703), a second telescopic straight rod (704), a spherical hinge (705), a grab bucket (706), a sliding device (707), a helium-neon laser (708) and a CCD camera (709); The top of the test base (1) is fixedly provided with two model groove tracks (401), the top of the two model groove tracks (401) is slidably connected with a pulley trolley (402), the bottom of the pulley trolley (402) is provided with two track axles (4021), the two ends of the two track axles (4021) are rotatably connected with pulley bodies (4022) slidably connected with the model groove tracks (401), and the bottom of the main model groove (2) is connected with the top of the pulley trolley (402); The main model groove (2) is made of transparent organic glass, the main model groove (2) is a rectangular box with an open upper end, the main model groove (2) is internally provided with a U-shaped clamping groove (201), an underground continuous wall simulation plate (202) and a square column-shaped movable panel (203), the U-shaped clamping groove (201) is arranged on the inner side of the two side walls of the main model groove (2), the length direction of the two side walls of the main model groove (2) is parallel to the length direction of the model groove track (401), the underground continuous wall simulation plate (202) and the square column-shaped movable panel (203) are movably connected to the U-shaped clamping groove (201), the square column-shaped movable panel (203) divides the main model groove (2) into two areas, namely a first model groove area (204) and a second model groove area (205), the second model groove area (205) is a model groove area in the moving direction of the main model groove (2), and the first model groove area (204) is another area of the main model groove (2); The top of the test base (1) is fixedly installed with four first columns (501), the top of the four first columns (501) is fixedly installed with a first platform (502), the top of the first platform (502) is installed with a storage box (503), the side of the storage box (503) is installed with a 3D printer (504), the 3D printer (504) is connected with the storage box (503) through a slide (505), the top of the test base (1) and the bottom of the first platform (502) are fixedly installed with a mechanical arm (506), and the end of the mechanical arm (506) is installed with a main stirrer (507). The inside of the storage box (503) is divided into two compartments, two said compartments are a liquid compartment (5033) and a particle compartment (5034), the bottom of the liquid compartment (5033) and the particle compartment (5034) is provided with a discharge port (5031), the discharge port (5031) is provided with a solenoid valve (5032), and the inside of the liquid compartment (5033) is provided with two small stirrers (50331).

2. The model test device for simulating excavation of a foundation pit based on 3D printed transparent soil according to claim 1, characterized in that: The top of the test base (1) is fixedly installed with four second columns (601), the top of the four second columns (601) is fixedly installed with a second platform (602), the inside of the second platform (602) is fixedly installed with a first telescopic straight rod (603), the bottom of the first telescopic straight rod (603) is fixedly installed with a vacuum cover plate (604), the inside of the first telescopic straight rod (603) is installed with a flexible pipe (605), the top of the second platform (602) is fixedly installed with a vacuum pump (606), the second platform (602) is fixedly installed with an air valve (607) connected with the flexible pipe (605), the vacuum pump (606) is connected with the air valve (607) through the flexible pipe (605), and the second platform (602) is installed with an air pressure gauge (608) connected with the air valve (607).

3. The model test device for simulating excavation of a foundation pit based on 3D printed transparent soil according to claim 2, characterized in that: The top of the test base (1) is fixedly provided with four third columns (701), and the top of the four third columns (701) is provided with a rectangular frame (702). The rectangular frame (702) comprises a first cross beam (7021), a second cross beam (7022), a first longitudinal beam (7023) and a second longitudinal beam (7024). The length direction of the first cross beam (7021) and the second cross beam (7022) is parallel to the length direction of the model groove track (401), and the length direction of the first longitudinal beam (7023) and the second longitudinal beam (7024) is perpendicular to the length direction of the model groove track (401). The first longitudinal beam (7023) is away from the vacuum saturation system (6), and the second longitudinal beam (7024) is close to the vacuum saturation system (6). The outer side surface of the first longitudinal beam (7023) is provided with a first sliding rail, and the inner and outer side surfaces of the first cross beam (7021) and the second cross beam (7022) are provided with second sliding rails. A cross longitudinal beam (703) is arranged between the first cross beam (7021) and the second cross beam (7022).

4. The model test device for simulating excavation of a foundation pit based on 3D printed transparent soil according to claim 3, characterized in that: The two ends of the cross longitudinal beam (703) are provided with a first sliding device (7071) and a second sliding device (7072), which are in sliding connection with the second sliding rails on the inner sides of the first cross beam (7021) and the second cross beam (7022). The lower surface of the cross longitudinal beam (703) is provided with a third sliding rail, and the third sliding rail on the lower surface of the cross longitudinal beam (703) is in sliding connection with a third sliding device (7073). The outer side surface of the first longitudinal beam (7023) is in sliding connection with a fourth sliding device (7074) through the first sliding rail. The second sliding rails on the outer sides of the first cross beam (7021) and the second cross beam (7022) are in sliding connection with a fifth sliding device (7075) and a sixth sliding device (7076). The bottoms of the first sliding device (7071), the second sliding device (7072), the third sliding device (7073), the fourth sliding device (7074), the fifth sliding device (7075) and the sixth sliding device (7076) are fixedly provided with a second telescopic straight rod (704). The second telescopic straight rod (704) at the bottom of the third sliding device (7073) is connected with a grab bucket (706) through a ball hinge (705). The bottom of the front second telescopic straight rod (704) is fixedly provided with a helium-neon laser (708), and the bottoms of the left and right second telescopic straight rods (704) are fixedly provided with CCD cameras (709).

5. The model test device for simulating excavation of a foundation pit based on 3D printed transparent soil according to claim 4, characterized in that: The bottoms of the first column (501), the second column (601) and the third column (701) are fixed with the test base (1) through a first nut, and the tops of the first column (501), the second column (601) and the third column (701) are connected with the first platform (502), the second platform (602) and the rectangular frame (702) through a second nut.

6. A method of using a model test apparatus for simulating excavation of a foundation pit based on 3D-printed transparent soil, characterized in that: The steps include: Step one: install and debug the control analysis platform (3), track system (4), transparent soil preparation system (5), vacuum saturation system (6) and simulated excavation system (7); Step two: control the 3D printer (504) to print granular materials through the control analysis platform (3), the granular materials are added to the granular bin (5034) through the slide (505), the phenyl methyl silicone oil and the No. 15 white oil are added to the liquid bin (5033) at a mass ratio of 2:5, and the liquid materials are uniformly stirred through the small stirrer (50331); Step three: arrange the square column-shaped movable panel (203) in the main model groove (2) through the U-shaped clamping groove (201), move the main model groove (2) to the right below the storage box (503) through the control analysis platform (3), and move the main stirrer (507) to the first model groove area (204) through the mechanical arm (506); Step four: input the amount of transparent soil material through the control analysis platform (3), then open the electromagnetic valve (5032) at the main stirrer (507) and the discharge port (5031), the transparent soil material flows into the inside of the first model groove area (204), and the main stirrer (507) uniformly stirs the transparent soil material in the first model groove area (204); Step five: when the amount of transparent soil material meets the requirements, close the electromagnetic valve (5032) and the main stirrer (507), move the main stirrer (507) away from the main model groove (2) through the mechanical arm (506), and arrange the underground continuous wall simulation board (202) in the first model groove area (204) through the U-shaped clamping groove (201); Step six: move the main model groove (2) to the right below the vacuum cover plate (604) through the control analysis platform (3), move the vacuum cover plate (604) down and seal the excavation main model groove (2), connect the vacuum pump (606) to the air valve (607) through the flexible pipe (605), open the vacuum pump (606) and the air valve (607), and close the vacuum pump (606) and the air valve (607) when the air pressure gauge (608) reading meets the requirements; Step seven: move the flexible pipe (605) away from the air valve (607), open the air valve (607), and move the vacuum cover plate (604) up and separate from the main model groove (2); Step eight: move the main model groove (2) to the designated position of the simulated excavation system (7) through the control analysis platform (3), adjust the positions and angles of the helium-neon laser (708) and the CCD camera (709) on the rectangular frame (702) through the control analysis platform (3), and turn on the CCD camera (709) and the helium-neon laser (708) after adjusting the positions and angles of the CCD camera (709) and the helium-neon laser (708). Step nine: the first square column movable panel (203) is grabbed by the grab bucket (706) on the rectangular frame (702) controlled by the analysis console (3), the first layer of excavated soil flows into the inside of the second model groove area (205), and at the same time, the first layer of excavated soil is put into the inside of the second model groove area (205) by the grab bucket (706) on the rectangular frame (702) controlled by the analysis console (3); Step ten: after the first layer of soil is excavated, the second square column movable panel (203) is grabbed by the grab bucket (706) on the rectangular frame (702) controlled by the analysis console (3), and step nine is repeated until the specified depth is excavated; Step eleven: the CCD camera (709) continuously takes pictures and sends the collected information to the analysis console (3), and the analysis console (3) analyzes and processes the collected information; Step twelve: after the simulation excavation test is completed, the test results are recorded, the main model groove (2) is removed, and the transparent soil material is removed.

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