EICP combined polymer reinforced soil sample preparation and performance testing device and use method thereof

Abstract

The invention belongs to the technical field of reinforced soil sample preparation and performance testing, and provides an EICP combined polymer reinforced soil sample preparation and performance testing device and a using method thereof.The EICP combined polymer reinforced soil sample preparation and performance testing device comprises a testing device body and a reinforced soil sample preparation mold, a turning cover is arranged at the top end of the testing device body, and a sealing cover is arranged at the top end of the turning cover; a 3D scanner is installed on the bottom face of the flip cover, a spraying shower head is further arranged at the top end of the testing device body, air blowers are arranged on one set of opposite side walls of the testing device body, and baking lamps are arranged on the other set of opposite side walls of the testing device body. A water tank, a water tank lifter and an electronic scale are arranged at the bottom end in the testing device body, the bottom of the water tank is connected with the water tank lifter, and the electronic scale is placed below the water tank; a soil sample lifter is arranged in the water tank, a test soil sample is placed at the top of the soil sample lifter, and the bottom of the soil sample lifter is fixedly connected with the water tank. According to the invention, the sample preparation of the reinforced soil can be carried out, and a plurality of properties of the reinforced soil can be tested.

Description

Technical Field

[0001] The invention belongs to the technical field of reinforced soil sample preparation and performance testing, and in particular, relates to an EICP combined polymer reinforced soil sample preparation and performance testing device and a use method thereof. Background Art

[0002] In recent years, the technology of soil reinforcement based on microorganisms has received extensive attention. At present, this technology mainly includes two directions: one is the direct cultivation of microbial induced calcium carbonate precipitation technology (MICP), which works by catalyzing the decomposition of urea through urease and producing CO3 through a series of chemical reactions. 2- ions, and Ca in anhydrous calcium chloride 2+ Ions bind to form CaCO3 crystals around microorganisms. Another direction is to directly use urease-induced calcium carbonate precipitation (EICP). However, due to the lack of microbial cells as templates, the calcium carbonate precipitate is not easy to aggregate in the EICP technology, so the size of the calcium carbonate crystals generated is small. Researchers have tried to introduce different polymer materials to solve this defect. The study found that combining skimmed milk powder with EICP soil reinforcement technology can improve the adhesion of precipitated carbonates and increase the strength of the treated soil; introducing hydrogel materials such as xanthan gum to assist urease in inducing calcium carbonate precipitation, it was found that hydrogels can retain moisture for a long time, prolong the reaction time, and increase the carbonate precipitation rate. There are also polymer materials such as cellulose, glutinous rice pulp, chitosan, lignin, etc., which can improve the defects of traditional EICP to varying degrees.

[0003] At present, the experimental research on EICP combined with polymer materials mainly focuses on strength. The research on the anti-erosion ability of reinforced sand, the deformation of reinforced clay and the water stability of both under dry-wet cycles has not yet been completed. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the present invention provides an EICP combined polymer reinforced soil sampling and performance testing device and a method of using the same. The device can perform reinforced soil sampling, reinforced sand anti-wind erosion test, reinforced sand anti-rain erosion test, reinforced sand water stability test, reinforced clay deformation measurement test and reinforced clay water stability test, so as to more comprehensively evaluate the performance of the reinforced soil.

[0005] The present invention adopts the following technical solution.

[0006] On the one hand, the present invention provides an EICP combined polymer reinforced soil sample preparation and performance testing device, comprising a test device body and a reinforced soil sample preparation mold, wherein a flap is provided at the top of the test device body, a 3D scanner is installed on the bottom of the flap, a spray shower is also provided at the top of the test device body, a hair dryer is provided on a group of side walls opposite to the test device body, and a baking lamp is provided on another group of side walls opposite to the test device body;

[0007] A water tank, a water tank lifter and an electronic scale are provided at the bottom of the test device body, the bottom of the water tank is connected to the water tank lifter, and the electronic scale is placed below the water tank; a soil sample lifter is provided in the water tank, a test soil sample is placed on the top of the soil sample lifter, and the bottom of the soil sample lifter is fixedly connected to the water tank; water inlets are provided on both sides of the water tank and the test device body, wherein the water inlet on one side is connected to the first water inlet pipe, and the water inlet on the other side is connected to the second water inlet pipe, one end of the first water inlet pipe is connected to the reaction liquid device, and one end of the second water inlet pipe is connected to the liquid storage tank, the reaction liquid device comprises a first reaction liquid container and a second reaction liquid container, the first reaction liquid container is filled with urease solution, the second reaction liquid container is filled with a mixed solution of a binder and a polymer material, and the liquid storage tank is filled with pure water;

[0008] The EICP combined polymer reinforced soil sample preparation and performance testing device also includes a suction sensor, a displacement sensor and a Shaw strength meter. The suction sensor is arranged at the top of the test device body and is located above the test soil sample. The displacement sensor is installed on the four side walls of the test device body, and the displacement sensors are evenly distributed around the test soil sample. The Shaw strength meter is placed on the surface of the test soil sample.

[0009] The reinforced soil sample mold comprises a detachable shell, a geotextile and a permeable stone. The inner wall of the detachable shell is paved with the geotextile. The assembled detachable shell has an opening on the top and a permeable stone on the bottom.

[0010] Furthermore, the first water inlet pipe is connected to the first reaction liquid container and the second reaction liquid container through a T-shaped three-way valve; the first water inlet pipe and the second water inlet pipe are also provided with an air pump for conveying the reaction liquid.

[0011] In the mixed solution of the binder and the polymer material, the polymer material is cellulose, the binder includes urea solution and calcium chloride solution, the binder is 1 mol / L, and the ratio of the binder to the cellulose is 1:1.

[0012] Furthermore, the EICP combined polymer reinforced soil sample preparation and performance testing device also includes an information collector and a computer. The information collector and the 3D scanner are connected to the computer. The information collector is connected to the displacement sensor, the Shaw strength meter and the suction sensor to receive the displacement information of the test soil sample, the surface strength information of the test soil sample and the surface suction information of the test soil sample, and transmit the information to the computer.

[0013] On the other hand, the present invention provides a method for using an EICP combined with a polymer reinforced soil sample preparation and performance testing device, which is applied to the above-mentioned EICP combined with a polymer reinforced soil sample preparation and performance testing device. The method for using the EICP combined with a polymer reinforced soil sample preparation and performance testing device for reinforced soil sampling comprises the following steps:

[0014] S1: Lay geotextile on the inner wall of the assembled removable shell and place permeable stone at the bottom of the removable shell;

[0015] S2: Add a certain amount of sand or clay and compact it layer by layer, and read the electronic scale reading m1;

[0016] S3: Turn on the air pump on the first water inlet pipe, and the urease solution flows into the water tank through the first water inlet pipe, and the soil sample lifter and the test soil sample thereon are controlled to descend and soak for 12 hours;

[0017] S4: The urease solution in the water tank is pumped back into the first reaction liquid container through the air pump on the first water inlet pipe, and then the air pump on the first water inlet pipe is turned on, and the mixed solution of the binder and the polymer material flows into the water tank, and the soil sample lifter and the test soil sample thereon are controlled to descend and soak for 12 hours;

[0018] S5: Control the soil sample lifter to rise, and pump the mixed solution of the binder liquid and the polymer material in the water tank back into the second reaction liquid container through the air pump on the first water inlet pipe, and weigh the weight m2;

[0019] S6: Repeat steps S3-S5 until the difference between two consecutive weighings is less than 1%, and the test soil sample is prepared. The prepared test soil sample is demoulded to obtain a weight of m3.

[0020] Furthermore, the use method of the EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced sand soil wind erosion resistance test includes:

[0021] Place the demoulding sand soil test sample on the soil sample lifter, turn on the hair dryer and set the wind force level of the hair dryer to n and the blowing time to t1. After the blowing is finished, weigh the test soil sample again to m4. Scan the surface of the test soil sample after the test with a 3D scanner to observe the surface erosion of the test soil sample. Calculate the wind erosion amount E and erosion rate V according to the mass difference before and after and the blowing time. E;

[0022] E=m3-m4

[0023]

[0024] Furthermore, the use method of the EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced sand soil anti-rain erosion test includes:

[0025] Place the demoulding sand soil test sample on the soil sample lifter, turn on the spray shower and set the water output to W, the spraying time to t2, after the spraying is over, turn on the baking lamp and set the temperature to T0, dry the test soil sample and weigh it to get the weight m5, and scan the surface of the test soil sample with a 3D scanner to observe the surface erosion of the test soil sample, and calculate the rain erosion amount D and erosion rate V according to the weight difference before and after and the raining time. D ;

[0026] D=m3-m5

[0027]

[0028] Furthermore, the use of the EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced sand water stability testing includes:

[0029] Place the demoulding sand soil test sample on the soil sample lifter, select representative points on the surface of the test soil sample, record the surface strength P1 with a Shaw strength meter, fill the water tank with pure water, immerse the test soil sample in the water through the soil sample lifter, and immerse for t3. After the immersion, raise the soil sample lifter and drain the water in the water tank, turn on the baking lamp and set the temperature to T0, dry the test soil sample, and weigh the weight of the dried test soil sample to be m6, and the surface strength to be P2; the mass loss ratio of the soil sample before and after immersion is the disintegration rate κ, and the strength loss ratio before and after immersion is the immersion strength loss rate λ;

[0030]

[0031] Furthermore, the use of the EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced clay soil deformation measurement test includes:

[0032] Place the demoulding clay soil test sample on the soil sample lifter, measure the average displacement of the test soil sample around it with a displacement sensor as L, and measure the original height of the test soil sample with a ruler as h;

[0033] Pure water is placed in the water tank, and the test soil sample enters the water through the soil sample lifter. The soaking time is t3. After the soaking is completed, the soil sample lifter is raised and the water in the water tank is drained. The baking lamp is turned on and the temperature is set to T0 to dry the test soil sample. The average deformation displacement of the test soil sample is recorded as L', and the height of the test soil sample is measured with a ruler as h'; the original volume V1 and the changed volume V2 of the test soil sample are calculated, and the free expansion rate δ is calculated;

[0034]

[0035] Furthermore, the use of the EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced clay soil water stability test includes:

[0036] Place the demoulding clay soil test sample on the soil sample lifter, and use a 3D scanner to shoot the surface of the test soil sample, and obtain the area of ​​the test soil sample as A. Fill the water tank with pure water, control the soil sample lifter to drive the test soil sample on it to immerse in water, and the immersion time is t3. After the immersion, raise the soil sample lifter and drain the water in the water tank, and record the weight of the soil sample after immersion m7. Turn on the baking lamp and set the temperature to T0, start drying the test soil sample, and record the weight of the test soil sample every 10 minutes. When the difference between two consecutive weighings does not exceed 0.1%, the weight of the test soil sample is m8. Use a suction sensor to test the suction M of the soil surface at different times c , calculate the moisture content ω according to the mass, and judge the soil and water conservation performance of the test soil sample by drawing the moisture content-suction relationship curve under the dry-wet cycle; use the 3D scanner 7 to shoot the soil surface, and use the data scanned by the 3D scanner to build a model and identify the area of ​​the soil surface without cracks as A ′ , the crack area is A″, then the cracking degree of the soil can be expressed as the crack rate μ:

[0037]

[0038] The beneficial effects of the present invention are as follows:

[0039] 1. The device provided by the present invention integrates the preparation of reinforced soil samples and the performance testing of test soil samples. Through the integrated design, the cumbersome process of traditional soil sample preparation and testing is simplified, and the work efficiency is improved.

[0040] 2. The device provided by the present invention can carry out reinforced sand anti-wind erosion test, reinforced sand anti-rain erosion test, reinforced sand water stability test, reinforced clay deformation measurement test and reinforced clay water stability test, so as to more comprehensively evaluate the stability of reinforced soil of different soil qualities under various environmental conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1It is a schematic diagram of the structure of the EICP combined polymer reinforced soil sample preparation and performance testing device provided by the present invention;

[0042] Figure 2 This is a front view of the EICP combined polymer reinforced soil sample preparation and performance testing device provided by the present invention;

[0043] Figure 3 It is a structural schematic diagram of the connection relationship between the water tank, the water tank lifter, the soil sample lifter and the electronic scale provided by the present invention;

[0044] Figure 4 It is a front view of the connection relationship between the water tank, the water tank lifter, the soil sample lifter and the electronic scale provided by the present invention;

[0045] Figure 5 It is a schematic diagram of the structure of the reinforced soil sample mold provided by the present invention.

[0046] In the figure: 1-test device body; 2-water tank; 3-soil sample lifter; 301-loading part; 302-lifting part; 303-fixing part; 4-water tank lifter; 5-electronic scale; 6-test soil sample; 7-3D scanner; 8-suction sensor; 9-spray shower; 10-heating lamp; 11-hair dryer; 12-Shaw strength meter; 13-displacement sensor; 14-reaction liquid device; 15-first reaction liquid container; 16-second reaction liquid container; 17-liquid storage tank; 18-air pump; 19-detachable shell; 20-geotextile; 21-permeable stone; 22-reinforced soil sample mold; 23-information collector; 24-computer. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only embodiments of a part of the present invention, rather than all embodiments. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0048] like Figure 1-2 As shown, the present invention provides an EICP combined polymer reinforced soil sample preparation and performance testing device, including a test device body 1 and a reinforced soil sample preparation mold 22. A flap is provided at the top of the test device body 1, and a 3D scanner 7 is installed on the bottom of the flap. The operator can reach into the test device body 1 through the flap to operate. A spray shower 9 is also provided at the top of the test device body 1. The number of spray showers 9 is 2 and they are arranged on both sides of the flap. A hair dryer 11 is provided on a set of opposite side walls of the test device body 1, and a heating lamp 10 is provided on another set of opposite side walls of the test device body 1.

[0049] A suction sensor 8, a displacement sensor 13 and a Shore strength meter 12 are also provided in the test device body 1. The suction sensor 8 is located above the test soil sample 6. There are four displacement sensors 13, which are arranged on the four side walls of the test device body 1. The displacement sensors 13 are evenly distributed around the test soil sample 6. The Shore strength meter 12 is placed on the surface of the test soil sample 6.

[0050] like Figure 3-4 As shown, a water tank 2 is installed at the bottom of the test device body 1, and a soil sample lifter 3 is arranged inside the water tank 2. A test soil sample 6 is placed on the top of the soil sample lifter 3. The bottom of the soil sample lifter 3 is fixedly connected to the water tank 2, and the connection between the soil sample lifter 3 and the water tank 2 is sealed. The soil sample lifter 3 includes a fixing part 303, a lifting part 302, and a loading part 301. The fixing part 303 is connected to the bottom of the water tank 2 and is used to fix the soil sample lifter 3 in the water tank 2. The lifting part 302 is used for lifting the soil sample lifter 3. The loading part 301 is used to place the test soil sample 6. The loading part 301, the lifting part 302, and the fixing part 303 are connected in sequence from top to bottom. In some embodiments, the fixed part 303 in the soil sample lifter 3 is a base, the lifting part 302 is a telescopic cylinder, the loading part 301 is a lifting workbench, the rear end cover of the telescopic cylinder is fixedly connected to the top surface of the fixed part 303, and the piston rod of the telescopic cylinder is fixedly connected to the bottom surface of the loading part 301. The lifting and lowering movement of the lifting part 302 is achieved by controlling the extension and retraction of the telescopic cylinder.

[0051] Four water tank lifters 4 are provided below the water tank 2. The water tank 2 is placed on the workbench of the water tank lifter 4. The water tank lifter 4 drives the water tank 2 to rise or fall, so that the water tank 2 is completely placed on the electronic scale 5 or away from the electronic scale 5. The water tank lifter 4 can use a spiral lifter, which drives the worm to rotate through a motor, and the worm drives the worm wheel to rotate at a reduced speed. The inner cavity of the worm wheel is processed into an internal thread to drive the lead screw to move up and down. In some embodiments, the water tank lifter 4 uses a hand-cranked lead screw lifter, which drives the lead screw to move up and down by manually shaking the rotating hand wheel, thereby realizing the lifting function. The water tank 2 can be lifted to different heights by the water tank lifter 4, so as to meet the requirements of different performance test experiments.

[0052] Water inlets are provided on both sides of the water tank 2 and the test device body 1, wherein the water inlet on one side is connected to the first water inlet pipe, and the water inlet on the other side is connected to the second water inlet pipe. One end of the first water inlet pipe is connected to the reaction liquid device 14, and the reaction liquid device 14 includes a first reaction liquid container 15 and a second reaction liquid container 16. The first reaction liquid container 15 is filled with urease solution, and the second reaction liquid container 16 is filled with a mixed solution of a binder and a polymer material. The first water inlet pipe is connected to the two reaction liquid containers through a T-type three-way valve. One end of the second water inlet pipe is connected to a liquid storage tank 17, and the liquid storage tank 17 is filled with pure water. An air pump 18 is provided on the first water inlet pipe and the second water inlet pipe, and the air pump 18 is used to transport liquid.

[0053] like Figure 5 As shown, the reinforced soil sample mold 22 includes a detachable shell 19, a geotextile 20 and a permeable stone 21. The inner wall of the detachable shell 19 is paved with the geotextile 20. The assembled detachable shell 19 has an opening on the top and a permeable stone 21 on the bottom.

[0054] The EICP combined polymer reinforced soil sample preparation and performance testing device also includes an information collector 23 and a computer 24. The information collector 23 and the 3D scanner 7 are connected to the computer 24. The information collector 23 is connected to the displacement sensor 13, the Shaw strength meter 12 and the suction sensor 8, and is used to receive the displacement information of the test soil sample 6, the surface strength information of the test soil sample and the surface suction information of the test soil sample, and transmit the information to the computer 24. The computer 24 receives the displacement information of the test soil sample, and calculates the free expansion rate according to the displacement information of the test soil sample and the height information of the test soil sample. The computer 24 receives the surface strength information of the test soil sample, and calculates the water immersion strength loss rate λ of the test soil sample according to the strength information. The computer 24 receives the surface suction information of the test soil sample in the water stability test, and calculates the moisture content and draws the moisture content-suction relationship curve according to the weight change and suction change of the test soil sample in the water stability test. The computer 24 receives the surface data information of the test soil sample transmitted by the 3D scanner, performs modeling and identifies the crack area on the surface of the test soil sample, and calculates the crack rate of the test soil sample.

[0055] In addition, the present invention also provides a method for using the EICP combined with polymer reinforced soil sampling and performance testing device, which can be used for reinforced soil sampling, reinforced sandy soil wind erosion resistance test, reinforced sandy soil rain erosion resistance test, reinforced sandy soil water stability test, reinforced clay soil deformation measurement test and reinforced clay soil water stability test.

[0056] When EICP is used in conjunction with polymer reinforced soil sample preparation and performance testing equipment as reinforced soil sample preparation, the method of use includes:

[0057] S1: Lay the geotextile 20 on the inner wall of the assembled detachable shell 19, and place the permeable stone 21 at the bottom of the detachable shell 19;

[0058] S2: Add a certain amount of sand or clay and compact it layer by layer, and read the reading of 5 m1 on the electronic scale;

[0059] S3: Turn on the air pump 18 on the first water inlet pipe, and the urease solution flows into the water tank through the first water inlet pipe, and the soil sample lifter 3 and the test soil sample 6 thereon are controlled to descend and soak for 12 hours;

[0060] S4: The urease solution in the water tank 2 is pumped back into the first reaction liquid container 15 through the air pump 18 on the first water inlet pipe, and then the air pump 18 on the first water inlet pipe is turned on, and the mixed solution of the binder and the polymer material flows into the water tank 2, and the soil sample lifter 3 and the test soil sample 6 thereon are controlled to descend and soak for 12 hours;

[0061] S5: Control the soil sample lifter 3 to rise, and pump the mixed solution of the binder liquid and the polymer material in the water tank 2 back into the second reaction liquid container 16 through the air pump 18 on the first water inlet pipe, and weigh the weight m2;

[0062] S6: Repeat steps S3-S5 until the difference between two consecutive weighings is less than 1%, and the test soil sample 6 is prepared. The prepared test soil sample 6 is demoulded, and the weight of the test soil sample 6 is m3.

[0063] In a preferred but non-limiting embodiment, the polymer material is cellulose, the binder includes urea solution and calcium chloride solution, the binder is 1 mol / L, and the ratio of the binder to the cellulose is 1:1. The preparation process of the binder is: 1. Dissolve 110g of calcium chloride in 500ml of pure water; 2. Dissolve 60g of urea in 500ml of pure water; 3. Mix the two solutions together.

[0064] When EICP is used in conjunction with polymer reinforced soil sample preparation and performance testing equipment for the wind erosion resistance test of reinforced sand, the usage methods include:

[0065] Place the demoulding sand soil test soil sample on the soil sample lifter 3, turn on the hair dryer 11 and set the wind force level of the hair dryer to n and the blowing time to t1. After the blowing is finished, weigh the test soil sample again to m4, and scan the surface of the test soil sample 6 after the test with the 3D scanner 7 to observe the surface erosion of the test soil sample 6. Calculate the wind erosion amount E and erosion rate V according to the mass difference before and after and the blowing time. E , record the erosion amount of soil samples at regular intervals, and determine the wind erosion resistance of the test soil samples by drawing an erosion amount-time relationship curve;

[0066] E=m3-m4

[0067]

[0068] In a preferred but non-limiting embodiment, if the wind erosion resistance of the reinforced sand is tested under mild wind erosion conditions, the wind force level n is 5-10 m / s, if the wind erosion resistance of the reinforced sand is tested under moderate wind erosion conditions, the wind force level n is 15-20 m / s, and if the wind erosion resistance of the reinforced sand is tested under extreme wind erosion conditions, the wind force level n is 25-30 m / s. In the wind erosion resistance test, the blowing time of the hair dryer is 10-20 minutes, the weight change of the soil sample is recorded every 2 minutes, and the weight change information of the soil sample is uploaded to the computer, and the computer draws the wind erosion rate-time curve under different wind erosion conditions.

[0069] When EICP is used in conjunction with polymer reinforced soil sample preparation and performance testing equipment as a test device for the rain erosion resistance of reinforced sandy soil, the method of use includes:

[0070] Place the demoulded sand soil test sample 6 on the soil sample lifter 3, turn on the spray shower 9 and set the water output to W, the spraying time to t2, after the spraying is finished, turn on the baking lamp 10 and set the temperature to T0, dry the test soil sample 6 and weigh it to obtain a weight of m5, and scan the surface of the test soil sample 6 with a 3D scanner 7 to observe the surface erosion of the test soil sample 6, and calculate the rain erosion amount D and erosion rate V according to the weight difference before and after and the raining time. D ; Record the erosion amount of the soil sample at regular intervals, and determine the rain erosion resistance of the test soil sample by drawing an erosion amount-time relationship curve;

[0071] D=m3-m5

[0072]

[0073] In a preferred but non-limiting embodiment, if the rain erosion resistance of the reinforced sand is tested under light rainfall conditions, the water output W is 10-20 liters / square meter / hour, if the rain erosion resistance of the reinforced sand is tested under moderate rainfall conditions, the water output W is 30-50 liters / square meter / hour, and if the rain erosion resistance of the reinforced sand is tested under extreme rainfall conditions, the water output W is 50 liters / square meter / hour. In the rain erosion resistance test, the spraying time of the spray shower is 10-20 minutes, and the weight change of the soil sample is recorded every 2 minutes, and the weight change information of the soil sample is uploaded to the computer, and the computer draws the rain erosion rate-time curve under different rain erosion conditions.

[0074] When EICP is used in conjunction with polymer reinforced soil sample preparation and performance testing equipment as a reinforced sand water stability test, the method of use includes:

[0075] Place the demoulding sand soil test sample 6 on the soil sample lifter 3, select representative points on the surface of the test soil sample 6, use the Shaw strength meter 12 to record the surface strength P1, fill the water tank 2 with pure water, immerse the test soil sample 6 in the water through the soil sample lifter 3, and immerse for t3. After the immersion, lift the soil sample lifter 3 and drain the water in the water tank 2, turn on the baking lamp 10 and set the temperature to T0, dry the test soil sample 6, and weigh the dried test soil sample 6 to obtain a weight of m6 and a surface strength of P2; the mass loss ratio of the soil sample before and after immersion is the disintegration rate κ, and the strength loss ratio before and after immersion is the immersion strength loss rate λ. Record the disintegration rate of the soil sample at regular intervals, and judge the water stability of the test soil sample by drawing a disintegration rate-time relationship curve;

[0076]

[0077] When EICP is used in conjunction with polymer reinforced soil sample preparation and performance testing equipment as a reinforced clay soil deformation measurement test, the usage includes:

[0078] The demoulded clay soil test sample 6 is placed on the soil sample lifter 3, and the displacement average value of the four sides of the test soil sample 6 is measured by the displacement sensor 13 as L, and the original height of the test soil sample 6 is measured by a ruler as h;

[0079] Pure water is placed in the water tank 2, and the test soil sample 6 enters the water through the soil sample lifter 3. The soaking time is t3. After the soaking is completed, the soil sample lifter 3 is raised and the water in the water tank 2 is drained. The baking lamp 10 is turned on and the temperature is set to T0 to dry the test soil sample 6. The average deformation displacement of the test soil sample 6 is recorded as L', and the height of the test soil sample is measured with a ruler as h'; the original volume V1 and the changed volume V2 of the test soil sample 6 are calculated, and the free expansion rate δ is calculated;

[0080]

[0081] When EICP is used in conjunction with polymer reinforced soil sample preparation and performance testing equipment as a reinforced clay soil water stability test, the method of use includes:

[0082] The demoulding clay soil test sample 6 is placed on the soil sample lifter 3, and the surface of the test soil sample 6 is photographed with a 3D scanner 7, and the area of ​​the test soil sample 6 is obtained as A. Pure water is filled in the water tank 2, and the soil sample lifter 3 is controlled to drive the test soil sample 6 thereon to immerse in the water. The immersion time is t3. After the immersion, the soil sample lifter 3 is raised and the water in the water tank 2 is drained, and the weight of the soil sample after immersion is recorded m7. The baking lamp 10 is turned on and the temperature is set to T0, and the test soil sample 6 is dried. The weight of the test soil sample 6 is recorded every 10 minutes. When the difference between two consecutive weighings does not exceed 0.1%, the weight of the test soil sample 6 is obtained as m8. The suction sensor 8 is used to test the suction M of the soil surface at different times.c , calculate the moisture content ω according to the mass, and judge the soil and water conservation performance of the test soil sample 6 by drawing the moisture content-suction relationship curve under the dry-wet cycle; use the 3D scanner 7 to shoot the soil surface, and use the data scanned by the 3D scanner to build a model and identify the area of ​​the soil surface without cracks as A ′ , the crack area is A″, then the cracking degree of the soil can be expressed as the crack rate μ:

[0083]

[0084] The soil and water conservation performance of the test soil sample is judged according to the moisture content-suction relationship curve. If the curve is relatively flat as a whole, it means that the suction changes relatively little within a larger moisture content range, and the soil's water holding capacity is good. Conversely, if the curve is relatively steep as a whole, it means that the suction changes significantly within a smaller moisture content range, and the soil's water holding capacity is poor.

[0085] In a preferred but non-limiting embodiment, the temperature T0 of the baking lamp is 70-90° C., and the soaking time t3 is 12-14 hours.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An EICP combined polymer reinforced soil sample preparation and performance testing device, comprising a test device body and a reinforced soil sample preparation mold, characterized in that: The top of the test device body is provided with a flap, the bottom of the flap is provided with a 3D scanner, the top of the test device body is also provided with a spray shower, a set of side walls opposite to the test device body is provided with a hair dryer, and another set of side walls opposite to the test device body is provided with a baking lamp; A water tank, a water tank lifter and an electronic scale are provided at the bottom of the test device body, the bottom of the water tank is connected to the water tank lifter, and the electronic scale is placed below the water tank; a soil sample lifter is provided in the water tank, a test soil sample is placed on the top of the soil sample lifter, and the bottom of the soil sample lifter is fixedly connected to the water tank; water inlets are provided on both sides of the water tank and the test device body, wherein the water inlet on one side is connected to the first water inlet pipe, and the water inlet on the other side is connected to the second water inlet pipe, one end of the first water inlet pipe is connected to the reaction liquid device, and one end of the second water inlet pipe is connected to the liquid storage tank, the reaction liquid device comprises a first reaction liquid container and a second reaction liquid container, the first reaction liquid container is filled with urease solution, the second reaction liquid container is filled with a mixed solution of a binder and a polymer material, and the liquid storage tank is filled with pure water; The EICP combined polymer reinforced soil sample preparation and performance testing device also includes a suction sensor, a displacement sensor and a Shaw strength meter. The suction sensor is arranged at the top of the test device body and is located above the test soil sample. The displacement sensor is installed on the four side walls of the test device body, and the displacement sensors are evenly distributed around the test soil sample. The Shaw strength meter is placed on the surface of the test soil sample. The reinforced soil sample mold comprises a detachable shell, a geotextile and a permeable stone. The inner wall of the detachable shell is paved with the geotextile. The assembled detachable shell has an opening on the top and a permeable stone on the bottom.

2. The EICP combined polymer reinforced soil sample preparation and performance testing device according to claim 1, characterized in that: The first water inlet pipe is connected to the first reaction liquid container and the second reaction liquid container through a T-shaped three-way valve; the first water inlet pipe and the second water inlet pipe are also provided with an air pump for conveying the reaction liquid.

3. The EICP combined polymer reinforced soil sample preparation and performance testing device according to claim 2, characterized in that: In the mixed solution of the binder and the polymer material, the polymer material is cellulose, the binder includes a urea solution and a calcium chloride solution, the binder is 1 mol / L, and the ratio of the binder to the cellulose is 1:

1.

4. The EICP combined polymer reinforced soil sample preparation and performance testing device according to claim 3, characterized in that: The EICP combined polymer reinforced soil sample preparation and performance testing device also includes an information collector and a computer. The information collector and the 3D scanner are connected to the computer. The information collector is connected to the displacement sensor, the Shaw strength meter and the suction sensor to receive the displacement information of the test soil sample, the surface strength information of the test soil sample and the surface suction information of the test soil sample, and transmit the information to the computer.

5. A method for using an EICP combined with polymer reinforced soil sample preparation and performance testing device, applied to an EICP combined with polymer reinforced soil sample preparation and performance testing device as claimed in any one of claims 1 to 4, characterized in that: The method for using the EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced soil sample preparation comprises the following steps: S1: Lay geotextile on the inner wall of the assembled removable shell and place permeable stone at the bottom of the removable shell; S2: Add a certain amount of sand or clay and compact it layer by layer, and read the electronic scale reading m1; S3: Turn on the air pump on the first water inlet pipe, and the urease solution flows into the water tank through the first water inlet pipe, and the soil sample lifter and the test soil sample thereon are controlled to descend and soak for 12 hours; S4: The urease solution in the water tank is pumped back into the first reaction liquid container through the air pump on the first water inlet pipe, and then the air pump on the first water inlet pipe is turned on, and the mixed solution of the binder and the polymer material flows into the water tank, and the soil sample lifter and the test soil sample thereon are controlled to descend and soak for 12 hours; S5: Control the soil sample lifter to rise, and pump the mixed solution of the binder liquid and the polymer material in the water tank back into the second reaction liquid container through the air pump on the first water inlet pipe, and weigh the weight m2; S6: Repeat steps S3-S5 until the difference between two consecutive weighings is less than 1%, and the test soil sample is prepared. The prepared test soil sample is demoulded to obtain a weight of m3.

6. The method for using the EICP combined with polymer reinforced soil sample preparation and performance testing device according to claim 5, characterized in that: The use of EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced sand anti-wind erosion test includes: Place the demoulding sand soil test sample on the soil sample lifter, turn on the hair dryer and set the wind force level of the hair dryer to n and the blowing time to t1. After the blowing is finished, weigh the test soil sample again to m4. Scan the surface of the test soil sample after the test with a 3D scanner to observe the surface erosion of the test soil sample. Calculate the wind erosion amount E and erosion rate V according to the mass difference before and after and the blowing time. E ; Record the erosion amount of the soil sample at regular intervals, and determine the wind erosion resistance of the test soil sample by drawing an erosion amount-time relationship curve; E=m3-m4 7. The method for using the EICP combined with polymer reinforced soil sample preparation and performance testing device according to claim 6, characterized in that: The use of EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced sand soil anti-rain erosion test includes: Place the demoulding sand soil test sample on the soil sample lifter, turn on the spray shower and set the water output to W, the spraying time to t2, after the spraying is over, turn on the baking lamp and set the temperature to T0, dry the test soil sample and weigh it to get the weight m5, and scan the surface of the test soil sample with a 3D scanner to observe the surface erosion of the test soil sample, and calculate the rain erosion amount D and erosion rate V according to the mass difference before and after and the raining time. D ; Record the erosion amount of the soil sample at regular intervals, and determine the rain erosion resistance of the test soil sample by drawing an erosion amount-time relationship curve; D=m3-m5 8. The method for using the EICP combined with polymer reinforced soil sample preparation and performance testing device according to claim 7, characterized in that: The use of EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced sand water stability test includes: Place the demoulding sand soil test sample on the soil sample lifter, select representative points on the surface of the test soil sample, record the surface strength P1 with a Shaw strength meter, fill the water tank with pure water, immerse the test soil sample in the water through the soil sample lifter, and immerse for t3. After the immersion, raise the soil sample lifter and drain the water in the water tank, turn on the baking lamp and set the temperature to T0, dry the test soil sample, and weigh the dried test soil sample to have a weight of m6 and a surface strength of P2; the mass loss ratio of the soil sample before and after immersion is the disintegration rate κ, and the strength loss ratio before and after immersion is the immersion strength loss rate λ; record the disintegration rate of the soil sample at regular intervals, and judge the water stability of the test soil sample by drawing a disintegration rate-time relationship curve; 9. The method for using the EICP combined with polymer reinforced soil sample preparation and performance testing device according to claim 5, characterized in that: The use of EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced clay soil deformation measurement test includes: Place the demoulding clay soil test sample on the soil sample lifter, measure the average displacement of the test soil sample around it with a displacement sensor as L, and measure the original height of the test soil sample with a ruler as h; Pure water is placed in the water tank, and the test soil sample enters the water through the soil sample lifter. The soaking time is t3. After the soaking is completed, the soil sample lifter is raised and the water in the water tank is drained. The baking lamp is turned on and the temperature is set to T0 to dry the test soil sample. The average deformation displacement of the test soil sample is recorded as L', and the height of the test soil sample is measured with a ruler as h'; the original volume V1 and the changed volume V2 of the test soil sample are calculated, and the free expansion rate δ is calculated; 10. The method for using the EICP combined with polymer reinforced soil sample preparation and performance testing device according to claim 5, characterized in that: The use of EICP combined with polymer reinforced soil sample preparation and performance testing device for reinforced clay soil water stability test includes: Place the demoulding clay soil test sample on the soil sample lifter, and use a 3D scanner to shoot the surface of the test soil sample, and obtain the area of ​​the test soil sample as A. Fill the water tank with pure water, control the soil sample lifter to drive the test soil sample on it to immerse in water, and the immersion time is t3. After the immersion, raise the soil sample lifter and drain the water in the water tank, and record the weight of the soil sample after immersion m7. Turn on the baking lamp and set the temperature to T0, start drying the test soil sample, and record the weight of the test soil sample every 10 minutes. When the difference between two consecutive weighings does not exceed 0.1%, the weight of the test soil sample is m8. Use a suction sensor to test the suction M of the soil surface at different times c , calculate the moisture content ω according to the mass, and judge the soil and water conservation performance of the test soil sample by drawing the moisture content-suction relationship curve under the dry-wet cycle; use the 3D scanner 7 to shoot the soil surface, and use the data scanned by the 3D scanner to build a model and identify the area of ​​the soil surface without cracks as A ′ , the crack area is A″, then the cracking degree of the soil can be expressed as the crack rate μ:

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