A temperature-controlled and variable-strength anti-sliding pile intelligent model test system and method

Abstract

The present invention relates to an intelligent model test system and method for anti-sliding piles with variable temperature control and strength. The test system includes: anti-sliding piles with variable temperature control and strength, a model box, model test materials, a deformation monitoring system, a loading system and a shock-absorbing platform. The present invention uses 3D printing technology to produce models with different filling densities, filling methods and different strengths, adopts transparent soil technology, an image acquisition system, and uses piv particle flow data analysis software to process data, thereby realizing the monitoring of the deformation of the soil before and after the anti-sliding piles. The various components of the model test system are miniaturized, which realizes the refinement and intelligent control of the model test. Various materials for the model test can be reused, reducing the amount of model test engineering.

Description

Technical Field

[0001] The present invention relates to the field of anti-slide pile model tests, and more specifically, to an intelligent model test system and method for anti-slide piles with variable temperature-controlled strength. Background Art

[0002] Model tests are one of the important means in geotechnical engineering research, aiming to obtain relevant parameters of structures or geotechnical bodies by conducting corresponding tests on scaled-down or equal-proportion models. Currently, there are mainly several problems in geotechnical engineering model tests: First, the model tests are large-scale, with the model test size generally ranging from one meter to several meters, and it takes several weeks or even months to complete a model test, which is time-consuming and laborious; Second, the test process is difficult to control and has poor repeatability; Third, the strength of the structure remains unchanged during the model test process; Fourth, when the structure interacts with the soil, it is difficult to monitor the deformation of the soil. Similar problems also exist in anti-slide pile model tests, including the difficulty in monitoring the deformation of the soil around the pile. Especially during the model test process, when the sliding force is certain, the model test fails because the strength of the anti-slide pile model material is too large and no deformation occurs, and it is time-consuming and laborious to repeat the model test.

[0003] In summary, model tests urgently need to be miniaturized, and be able to monitor test data in a refined and intelligent manner, achieve changes in the strength of the structure for special needs, and be repeatable and carried out quickly. Summary of the Invention

[0004] In view of the above problems, the present invention proposes an intelligent model test system and method for anti-slide piles with variable temperature-controlled strength, which overcomes the problems in the existing anti-slide pile model test process such as large-scale model tests, difficult test process control, difficult repeated test, difficult monitoring of the deformation of the soil around the pile, and model test failure caused by too large strength of the anti-slide pile. It can be used for aspects such as analysis of the deformation law of anti-slide piles, research on pile-soil interaction, and demonstration of geotechnical test teaching.

[0005] An intelligent model test system for anti-slide piles with variable temperature-controlled strength includes: an anti-slide pile with variable temperature-controlled strength, a model box, model test materials, a deformation monitoring system, a loading system, and a shock absorption table, where:

[0006] The anti-slide pile with variable temperature-controlled strength is composed of an anti-slide pile, electric heating wires, and a temperature control box; electric heating wires are arranged in the hollow structure of the anti-slide pile, and the heating of the electric heating wires is controlled by the power supply and current control module in the temperature control box. The anti-slide pile is made by 3D printing to obtain models with different filling densities and filling methods, and models with different strengths are obtained by using different 3D printing materials;

[0007] The model box comprises an upper part and a lower part. The upper part is where the free section of the anti-slip pile is located. A hole is drilled at the bottom for placing the anti-slip pile. The highly transparent thick-layer acrylic plate is hollowed out by cutting and cutting to facilitate the image acquisition monitoring system to collect images. The lower part is where the embedded section of the anti-slip pile is located. It is made of multiple layers of acrylic plates spliced ​​and glued together. A hole is opened in the middle of the acrylic plate for placing the anti-slip pile.

[0008] The model test material is used to simulate the soil before and after the anti-sliding pile. It uses transparent soil obtained by mixing silica particles, dodecane and white oil. It is transparent and has tiny bubbles distributed. After laser irradiation, it shows a fluorescent state, which is convenient for the image acquisition monitoring system to obtain the deformation data of the soil before and after the anti-sliding pile;

[0009] The deformation monitoring system includes a structural strain monitoring system and an image acquisition monitoring system. The structural strain monitoring system for monitoring the deformation of the anti-sliding pile includes a strain gauge, a strain data acquisition box and a strain data acquisition software. The strain gauge is pasted on the front and rear surfaces of the anti-sliding pile and maintained at a certain interval. The strain gauge is connected to the strain data acquisition box with a wire. The strain data acquisition box is connected to a computer, and strain data acquisition software is used to collect strain data; the image acquisition monitoring system for monitoring the deformation of the soil before and after the anti-sliding pile includes a laser, a camera and acquisition software. The laser is suspended on the upper side of the model box and emits laser into the inside of the model test material. After the model test material is deformed by force, its displacement is captured by the camera. The camera is set on one side of the model box to take regular pictures of the deformation image of the model test material. After the test, the image is subjected to piv particle flow data analysis;

[0010] The loading system adopts hydraulic principle to simulate the landslide thrust borne by the anti-slide piles, and is composed of a hydraulic pump, a hydraulic sensor, an oil pipe, an ultra-thin jack and a loading plate.

[0011] Furthermore, the anti-slip pile is printed with TPU material. The characteristic of TPU material is that its strength decreases as the temperature increases, so that the strength of the anti-slip pile model decreases as the temperature increases, while maintaining a certain elasticity.

[0012] Furthermore, the current control module is composed of a rotary switch and several resistors. When the rotary button is rotated to different heating levels, the circuit is connected to resistors of different sizes, thereby changing the size of the pressure borne by the heating wire and realizing the control of the heating intensity of the heating wire.

[0013] Furthermore, the opening positions and opening sizes of the upper and lower parts of the model box should be consistent.

[0014] ​Further, the shock-absorbing platform is used to minimize the influence of ground vibration on the acquisition of model test data during the test.

[0015] Further, the hydraulic sensor can be connected to a computer via Bluetooth for facilitating real-time monitoring of the changes in oil pressure data.

[0016] Further, the loading plate is cut from a steel plate with a relatively large stiffness, and holes are drilled in the loading plate to facilitate the simulation of the penetration of the transparent soil material liquid through the loading plate during the test.

[0017] An intelligent model test method for anti-slide piles with variable temperature-controlled strength includes the following steps:

[0018] 1) Determine the dimensions of the anti-slide pile according to the test plan, including: the length of the embedded section of the anti-slide pile, the length of the free section, the cross-sectional shape and size of the anti-slide pile;

[0019] 2) 3D print the anti-slide pile. First, establish the model of the anti-slide pile in the modeling software, slice it by the 3D printer, and determine the filling method and density of the printed model;

[0020] 3) Place electric heating wires in the hollow structure of the anti-slide pile. Connect the electric heating wires to the control box with wires, and adjust the heating intensity of the electric heating wires through the rotary switch;

[0021] 4) Paste strain gauges on the front and back of the anti-slide pile and connect them to the acquisition box, and then check the initial strain data;

[0022] 5) Manufacture the model box. According to the dimensions and cross-sectional shape of the anti-slide pile, determine the dimensions of the model box, the thickness of each layer of acrylic board, and the size of the holes drilled in the acrylic board. Bond each part of the manufactured model box into shape and place it on the shock-absorbing platform;

[0023] 6) Preparation of the model test materials. Prepare the transparent soil material by mixing silica particles, dodecane, and white oil in a certain proportion;

[0024] 7) Debug the loading system. Connect the hydraulic sensor to the computer via Bluetooth and check the operation of the loading system;

[0025] 8) Place the ultra-thin jack, loading plate, and anti-slide pile in the model box. Stack the prepared model test materials in the model box, and use a glass rod to tamp and remove the larger air bubbles in the model test materials;

[0026] 9) Debug the image acquisition and monitoring system. Turn on the laser and camera to ensure that the deformed images can be acquired.

[0027] 10) Start the test, collect various types of data and pictures, including hydraulic data, strain data, deformed images, and change the rotation of the rotary switch and the strength of the anti-slide pile according to the requirements of the test plan.

[0028] The present invention has the following beneficial effects:

[0029] 1. The strength of the anti-slide pile is controllable. In one test, the deformation of anti-slide piles with different strengths can be measured. The anti-slide pile is fabricated using 3D printing technology, with high model size accuracy, convenient and fast fabrication process, and high fabrication efficiency.

[0030] 2. The model test material adopts transparent soil technology, an image acquisition system, and PIV particle flow data analysis software to process data, realizing the monitoring of the deformation of the soil body before and after the anti-slide pile.

[0031] 3. Each component of the model test system is miniaturized, realizing refined and intelligent control of the model test. Various materials for the model test can be reused, reducing the workload of the model test. Description of the Drawings

[0032] Figure 1 It is a schematic diagram of the intelligent model test system for an anti-slide pile with variable temperature-controlled strength of the present invention;

[0033] Figure 2 It is a top view schematic diagram of the model test details of the above embodiment;

[0034] Figure 3 It is a cross-sectional schematic diagram of the model test details of the above embodiment;

[0035] Figure 4 It is the retaining wall board of the model box of the above embodiment;

[0036] Figure 5 It is a schematic diagram of the variable temperature-controlled strength anti-slide pile system of the above embodiment;

[0037] Figure 6 It is a filling schematic diagram of the 3D printed anti-slide pile of the above embodiment;

[0038] Figure 7 It is a schematic diagram of the structural strain monitoring system of the above embodiment;

[0039] Figure 8 It is a schematic diagram of the structure of the model box of the above embodiment;

[0040] Figure 9 It is a cross-sectional schematic diagram of the model box of the above embodiment;

[0041] Figure 10 It is a schematic diagram of the loading system of the above embodiment;

[0042] Figure 11 It is the loading plate of the loading system of the above embodiment;

[0043] Annotation of reference numerals: 1 is a computer; 2 is a shock-absorbing platform; 3 is a model box; 3-1 is the upper half of the model box; 3-2 is the No. 1 plate of the lower half of the model box; 3-3 is the No. 2 plate of the lower half of the model box; 3-4 is the No. 3 plate of the lower half of the model box; 3-5 is the No. 4 plate of the lower half of the model box; 4 is a loading system; 4-1 is a hydraulic pump; 4-2 is a hydraulic sensor; 4-3 is a hydraulic pipe; 4-4 is an ultra-thin jack; 4-5 is a loading plate; 5 is a structural strain detection system; 5-1 is a strain data acquisition box; 5-2 is a strain gauge; 6 is a camera; 7 is a control box; 7-1 is an electric heating wire; 7-2 is a knob switch; 7-3 is a resistor; 7-4 is a power supply; 7-5 is an anti-slide pile; 7-6 is the cross-section of the anti-slide pile; 8 is a laser; 9 is a model test material; 10 is a cushion block; 11 is a retaining wall plate; 12 is a bracket. Detailed implementation mode

[0044] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. It should be noted that all the materials described in this invention patent can be purchased, and the commercial software and the manufacturing equipment can also be obtained by purchasing.

[0045] Embodiment 1

[0046] As Figures 1 to 11 shown, an intelligent model test system for anti-slide piles with variable temperature-controlled strength provided by the present invention includes an anti-slide pile with variable temperature-controlled strength, a model box 3, a model test material 9, a structural strain monitoring system 5, an image acquisition monitoring system, a loading system 4 and a shock-absorbing platform 2.

[0047] The anti-slide pile with variable temperature-controlled strength includes a control box 7, an electric heating wire 7-1, and an anti-slide pile 7-5. The control box 7 includes a knob switch 7-2, a resistor 7-3, and a power supply 7-4. By rotating the switch 7-2 and connecting different resistors 7-3 respectively, the heating intensity of the electric heating wire 7-1 can be controlled.

[0048] The model box 3 includes the upper half of the model box 3-1, the No. 1 plate 3-2 of the lower half of the model box, the No. 2 plate 3-3 of the lower half of the model box, the No. 3 plate 3-4 of the lower half of the model box, and the No. 4 plate 3-5 of the lower half of the model box.

[0049] The structural strain monitoring system 5 includes a strain data acquisition box 5-1, a strain gauge 5-2, and strain data acquisition software on the computer 1.

[0050] The image acquisition monitoring system includes a camera 6, a laser 8, image acquisition software and PIV particle flow analysis software on the computer 1.

[0051] The loading system 4 includes a hydraulic pump 4-1, a hydraulic sensor 4-2, a hydraulic pipe 4-3, an ultra-thin jack 4-4, and a loading plate 4-5.

[0052] The basic test steps of the above intelligent model test system for anti-slide piles with variable temperature control intensity are as follows:

[0053] Step 1: Determine the dimensions of anti-slide pile 7-5. The length of anti-slide pile 7-5 is 20 cm, the length of the embedded section is 10 cm, the length of the free section is 10 cm, the cross-section is circular, and the diameter is 2.5 cm. In this scheme, 4 anti-slide piles 7-5 are placed in parallel, and the center distance between the piles is 5 cm.

[0054] Step 2: 3D print anti-slide pile 7-5. The model of the 3D printer is the JGAURORA A8S type, and the printing material is the TPU K7 95A type 3D printing material. First, establish a model in SolidWorks software, and slice it with JGcreat software. As Figure 6 shown, the middle of anti-slide pile cross-section 7-6 adopts a triangular filling method, the filling density is 60%, and the filling density within 5 mm of the surface is 100%.

[0055] Step 3: Anti-slide pile 7-5 has a hollow structure. As Figure 6 shown, the middle hole diameter is 5 mm, which is used to place the electric heating wire 7-1. The electric heating wire 7-1 is connected to the control box 7, and the heating intensity of the electric heating wire 7-1 is controlled by rotating the knob switch 7-2. As Figure 5 shown.

[0056] Step 4: Strain gauges 5-2 are pasted on the front and back surfaces of anti-slide pile 7-5. The interval between strain gauges 5-2 is 2 cm. The strain gauges 5-2 are connected to the strain data acquisition box 5-1 with wires, and the strain data acquisition box 5-1 is connected to the computer 1. As Figure 7 shown.

[0057] Step 5: Make the model box 3. The upper half 3-1 of the model box is made by hollowing out a whole thick acrylic board. As Figure 8 and Figure 9 shown, the size of the thick acrylic board is 50 cm in length, 22 cm in width, and 12 cm in height. The size of the hollowed-out part in the middle is 45 cm in length, 20 cm in width, and 11 cm in height. The bottom thickness is 1 cm, the front and back wall thicknesses are 2.5 cm, the left and right wall thicknesses are 1 cm, and holes are drilled at the bottom, with a hole diameter of 2.5 cm and a hole center distance of 5 cm. The holes are located in the center of the bottom of the model box. As Figure 9 shown. The dimensions of the lower half 1st plate 3-2, the lower half 2nd plate 3-3, and the lower half 3rd plate 3-4 of the model box are 50 cm in length, 22 cm in width, and 3 cm in thickness. The drilling positions are the same as those of the upper half 3-1 of the model box. The length of the lower half 4th plate 3-5 of the model box is 50 cm, the width is 22 cm, and the thickness is 1 cm, and no holes need to be drilled. Each part of the model box 3 can be bonded together with a modified acrylate adhesive. The model box 3 is placed on the shock-absorbing table 2. AsFigure 1 as shown

[0058] Step six, preparation of the model test material 9. The mass ratio of dodecane to white oil used is 4:1, and the particle size of the silica particles is 0.5 mm.

[0059] Step seven, debugging of the loading system 4. The hydraulic sensor 4-2 is connected to the computer 1, the oil pipe is connected to the ultra-thin jack 4-4, the power supply of the hydraulic pump 4-1 is turned on, and the operation of the loading system 4 is detected.

[0060] Step eight, place the anti-slide pile 7-5 into the borehole in the model box 3, place the cushion block 10 at a corner of the model box 3, place the ultra-thin jack 4-4 on the cushion block 10, place the loading plate 4-5 closely against the ultra-thin jack 4-4, pour the silica particles into the model box 3, build a slope on one side and place the retaining plate 11, pour the liquid mixture of dodecane and white oil into the model box 3 until the liquid level is level with the anti-slide pile 7-5, as Figure 2 and Figure 3 shown. Use a glass rod to tamp and remove the larger air bubbles in the model test material 9.

[0061] Step nine, debugging of the image acquisition and monitoring system. Turn on the laser 8, the laser irradiates the model box 3, the camera 6 acquires images, and observe the acquired image situation on the computer 1.

[0062] Step ten, start the test. When it is determined that each system is working properly, start the hydraulic pump 4-1. The hydraulic sensor 4-2 records and transmits the hydraulic data to the computer 1. During this period, strain data and images are acquired. When the hydraulic data reaches the predetermined landslide thrust, turn off the hydraulic pump 4-1.

[0063] End the test, reset the ultra-thin jack 4-4, turn off the power supply of each system, recycle the model test material 9 for use in the next test. Sort out each component and place it in the designated position for use in the next test.

[0064] In step two, the TPU K7 95A type 3D printing material is a flexible material, and the printed model has good elasticity. The melting point of the material is above 200 °C.

[0065] In step eight, there are multiple boreholes on the loading plate 4-5 and the retaining plate 12, through which the liquid mixture of white oil and dodecane can pass, preventing the silica particles from passing through.

[0066] In step ten, when the hydraulic pump 4-1 loads the hydraulic pressure to the predetermined landslide thrust, observe the deformation of the anti-slide pile 7-5. According to the test plan, the rotary switch 7-2 can be rotated to change the strength of the anti-slide pile 7-5. During this period, strain data and images are acquired, and analyze the deformation of the anti-slide pile 7-5 and the soil around the pile after the strength of the anti-slide pile 7-5 is reduced.

[0067] The above embodiments have been described in detail with reference to the examples of the present invention. However, the present invention is not limited to the above examples. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the gist of the present invention, and these should also be regarded as the protection scope of the present invention.

Claims

1. An intelligent model test system for anti-sliding piles with variable temperature control and strength, comprising: Temperature-controlled and variable-strength anti-slide piles, model boxes, model test materials, deformation monitoring systems, loading systems and shock-absorbing platforms, characterized in that: The temperature-controlled strength-variable anti-slip pile is composed of an anti-slip pile, an electric heating wire and a temperature control box; the electric heating wire is arranged in the hollow structure of the anti-slip pile, and the heating of the electric heating wire is controlled by a power supply and a current control module in the temperature control box; the anti-slip pile is formed by 3D printing to obtain models with different filling densities and filling methods, and models with different strengths are obtained by using different 3D printing materials; The model box comprises an upper part and a lower part of the model box. The upper part of the model box is where the free section of the anti-slip pile is located. A hole is drilled at the bottom for placing the anti-slip pile. The highly transparent thick-layer acrylic plate is hollowed out by cutting and hollowing to facilitate the image acquisition monitoring system to collect images. The lower part of the model box is where the embedded section of the anti-slip pile is located. It is formed by splicing and gluing multiple layers of acrylic plates. A hole is opened in the middle of the acrylic plate for placing the anti-slip pile. The model test material is used to simulate the soil before and after the anti-sliding pile. The transparent soil obtained by mixing silica particles, dodecane and white oil is transparent and has tiny bubbles distributed. After being irradiated by laser, it shows a fluorescent state, which is convenient for the image acquisition monitoring system to obtain the deformation data of the soil before and after the anti-sliding pile. The deformation monitoring system includes a structural strain monitoring system and an image acquisition monitoring system. The structural strain monitoring system for monitoring the deformation of the anti-sliding pile includes a strain gauge, a strain data acquisition box and a strain data acquisition software. The strain gauge is adhered to the front and rear surfaces of the anti-sliding pile and maintained at a certain interval. The strain gauge is connected to the strain data acquisition box with a wire. The strain data acquisition box is connected to a computer, and strain data acquisition software is used to collect strain data. The image acquisition monitoring system for monitoring the deformation of the soil before and after the anti-sliding pile includes a laser, a camera and an acquisition software. The laser is suspended on the upper side of the model box and emits laser light into the inside of the model test material. After the model test material is deformed by force, its displacement is captured by the camera. The camera is set on one side of the model box to take regular pictures of the deformation image of the model test material. After the test is completed, the image is subjected to piv particle flow data analysis. The loading system adopts hydraulic principle to simulate the landslide thrust borne by the anti-slide pile, and is composed of a hydraulic pump, a hydraulic sensor, an oil pipe, an ultra-thin jack and a loading plate; The anti-slip piles are printed with TPU material; The current control module is composed of a rotary switch and several resistors. When the rotary button is rotated to different heating levels, the circuit is connected to resistors of different sizes, thereby changing the size of the pressure borne by the heating wire and realizing the control of the heating intensity of the heating wire.

2. The temperature-controlled and variable-strength anti-sliding pile intelligent model test system according to claim 1 is characterized in that: The opening positions and opening sizes of the upper half of the model box and the lower half of the model box should be consistent.

3. The temperature-controlled and variable-strength anti-sliding pile intelligent model test system according to claim 2 is characterized by: The vibration-damping platform is used to reduce the influence of ground vibration on the model test data collection as much as possible during the test process.

4. The temperature-controlled and variable-strength anti-sliding pile intelligent model test system according to claim 3 is characterized by: The hydraulic sensor can be connected to a computer via Bluetooth to facilitate real-time monitoring of changes in oil pressure data.

5. The temperature-controlled and variable-strength anti-sliding pile intelligent model test system according to claim 4 is characterized by: The loading plate is cut from a steel plate with relatively high rigidity, and holes are drilled on the loading plate to facilitate transparent soil material liquid to penetrate the loading plate during the simulation test.

6. The test method of the temperature-controlled and variable-strength anti-sliding pile intelligent model test system according to any one of claims 1 to 5, characterized in that: The following steps are involved: 1) Determine the size of the anti-slide pile according to the test plan, including: the length of the embedded section of the anti-slide pile, the length of the free section, and the cross-sectional shape and size of the anti-slide pile; 2) 3D printing of anti-slip piles: First, the model of the anti-slip pile is established in the modeling software, sliced ​​by the 3D printer, and the filling method and density of the printed model are determined; 3) A heating wire is placed in the hollow structure of the anti-slip pile. The heating wire is connected to the control box with a wire, and the heating intensity of the heating wire is adjusted by rotating the switch; 4) Glue the strain gauges on the front and back of the anti-slip pile and connect them to the collection box to check the initial strain data; 5) Make a model box. According to the size and cross-sectional shape of the anti-slip piles, determine the size of the model box, the thickness of each layer of acrylic sheet, and the size of the drilling holes in the acrylic sheet. Bond the various parts of the prepared model box into shape and place it on the shock-absorbing platform. 6) Preparation of model test materials: preparing transparent soil materials according to a certain proportion of silica particles, dodecane and white oil; 7) Debugging of the loading system, connecting the hydraulic sensor to the computer via Bluetooth, and checking the operation of the loading system; 8) Place the ultra-thin jack, loading plate, and anti-slip pile in the model box, pile the configured model test materials in the model box, and use a glass rod to punch and pound to remove the larger bubbles in the model test materials; 9) Debug the image acquisition monitoring system, turn on the laser and camera to ensure that the deformed image can be acquired; 10) Start the test and collect various data and images, including hydraulic data, strain data, and deformation images. Change the strength of the rotary switch and anti-slip piles according to the requirements of the test plan.

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