Polymer composite ant cave material and preparation method thereof

Abstract

The invention relates to the field of ant cave simulation materials, and particularly discloses a polymer composite ant cave material and a preparation method thereof. The polymer composite ant cave material comprises the following raw materials: yellow clay, a curing agent and water, the use amount of the curing agent is 4-5wt% of the mass of the yellow clay, and the curing agent comprises cellulose, rubber powder and pregelatinized starch in a mass ratio of 1: (1-2): (2-3); the preparation method comprises the following steps: mixing the cellulose, the rubber powder and the pre-gelatinized starch, and uniformly stirring to obtain the curing agent; and adding water into the curing agent, uniformly stirring, mixing with the yellow clay, stirring for 120-150s, and curing at 20-25 DEG C for 7d. The ant cave simulation material is used for simulating a natural ant cave, truly reproduces complex behaviors of the ant cave in seepage, deformation and even dam break processes, and determines a reliable simulation material for an ant cave model.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ant nest simulation materials, and more particularly to a polymeric composite ant nest material and a preparation method thereof. BACKGROUND

[0002] There are many embankments of rivers and lakes in China, most of which are of homogeneous structure. The earth-rock dam provides an ideal living environment for termites due to its tall soil structure, suitable temperature and humidity, and sufficient food source. In addition to design and construction factors, animal nests such as termites are an important cause of abnormal seepage of dam body. The main and auxiliary nests and from horizontal ant paths built by termites in the dam can seriously damage the integrity of the dam structure, and can cause piping, scattered immersion, landslide, seepage and other hazards. However, due to the loose and porous nature of real ant nests and the difficulty of implementing operations, model tests are difficult to carry out.

[0003] In order to fundamentally prevent and control the damage of ant nests to the structural behavior and seepage stability of the dam, it is necessary to systematically study the mechanism of the damage. At present, the main research methods are machine learning, numerical simulation and model test. Although numerical simulation method has made significant progress in the study of the damage of ant nest system to water conservancy projects, it has a series of inherent limitations, which affect the accuracy and reliability of the simulation results. The main manifestations are as follows: distortion of constitutive relation and parameters; simulation of ant nest damage requires setting the constitutive relation of soil, but numerical simulation is difficult to truly describe the structural damage, particle loss, softening and mutation of soil caused by ant nests, and the input ant nest geometric parameters are often based on simplified assumptions; simulation of key processes is disabled; it is difficult to accurately reproduce the dynamic and random process of soil particles being started, transported and accumulated in the ant nest channel, as well as the positive feedback effect of the channel expanding caused thereby; and the lack of "anchor point" for comparison with physical model test, and the output results are not intuitive, the reliability of the cloud map and data output must be verified and calibrated by physical test data. The strength of numerical simulation lies in extrapolation and prediction, but the reliability of its foundation depends heavily on the verification and foundation of physical model test.

[0004] Therefore, to establish a universal causal law, model test is a test method that can be carried out under strict control of boundary conditions, and the scientific selection of ant nest system simulation material is the core link to ensure the scientificity and reliability of the test. The selected material must have high similarity in key physical parameters and properties with natural ant nests and surrounding fill, so as to truly reproduce the complex behavior of ant nests in the process of seepage, deformation and even dam failure. Due to the hidden structure and complex morphology of ant nests, it is difficult for traditional surveying and numerical simulation methods to truly reproduce the seepage failure mechanism of ant nests, so it is necessary to determine a scientific and reliable simulation material for physical model test of ant nest system. SUMMARY

[0005] In order to build the ant nest material of the ant nest model test, provide effective help for the subsequent model test, further reveal the disaster-causing mechanism of the ant nest system to the dam structure, so as to provide key theoretical basis and material basis for evaluating the ant hazard risk, developing ecological release repair technology and engineering prevention and control strategy, the application provides a kind of multi-composite ant nest material and preparation method thereof.

[0006] In the first aspect, the application provides a kind of multi-composite ant nest material, adopts the following technical scheme: A kind of multi-composite ant nest material, the raw material of the multi-composite ant nest material includes yellow clay, curing agent and water, the amount of the curing agent is 4-5wt% of the mass of yellow clay, and the mass ratio of the curing agent is 1:1-2:2-3 including cellulose, glue powder and pre-gelatinized starch.

[0007] By adopting the above technical scheme, cellulose, pre-gelatinized starch and glue powder contain calcium oxide, silicon dioxide and aluminum oxide, which can be slowly hydrated under the excitation of alkaline substance calcium oxide in glue powder, and react with active silicon dioxide and aluminum oxide therein to generate C-S-H and C-A-H etc. Gel material, the reaction formula is as follows: CaO+H2O+SiO2→C-S-H, CaO+H2O+Al2O3→C-A-H, these gel materials can bond clay particles, thereby improving the strength of the cured soil;And pre-gelatinized starch contains SO3, which provides Promote the generation of needle bar-like substance AFt (high-sulfur type hydrated calcium sulphoaluminate), the reaction formula is as follows: Needle bar-like AFt interlap to form high-strength skeleton structure, which can connect C-S-H cemented clay particles and form a whole, further improve its strength and skeleton stability.

[0008] After the yellow clay is cured, it is hydrolyzed when it is softened by water, that is, the reverse dissociation of the cementing system under the erosion of water, and the decomposition process reaction formula is as follows: C-A-H+H2O→Ca 2+ +[Al(OH)4] - 、 AFt+H2O→2Cl - +Al(OH)3, the network structure of C-S-H and C-A-H gel is destroyed, and a large amount of Ca 2+ 、 and [Al(OH)4] - ion is released;At the same time, the soluble by-products generated after dissolution produce Cl - and Ions not only increase porosity due to their own loss, but also raise the ion concentration in pore water, further catalyzing and intensifying the hydrolysis reaction of the main gel, ultimately leading to the rapid disintegration and softening of the solidified soil structure. Clay particles typically carry an electrical charge on their surface, attracting ions. In the early stages of hydrolysis, the ions adsorbed on the clay surface and hydrogen ions in the water disrupt the charge balance and structural stability of the clay particles, initiating the hydrolysis reaction. Clay contains minerals such as aluminosilicates, which begin to hydrolyze under the influence of water. The silicon-oxygen and aluminum-oxygen bonds in aluminosilicates gradually break under the attack of water molecules. [Al(OH)4] - It is released from clay minerals and enters the solution. AFt also hydrolyzes to Ca in the presence of water. 2+ The presence of cementing Al(OH)3 explains why the solidified soil exhibits certain cementing properties during hydrolysis. The action of water causes the material to lose its binding force, leading to the softening and disintegration of the soil, thus realistically reproducing the process of soil and water loss caused by the ant nest system in the dam body.

[0009] Preferably, the mass ratio of cellulose, adhesive powder and pregelatinized starch in the curing agent is 1:1:2.

[0010] By adopting the above technical solution, specific amounts of cellulose, adhesive powder, and pregelatinized starch can achieve the best curing effect, giving the yellow clay ant nest simulation material both sufficient strength and a certain degree of toughness. It can also simulate the characteristics of natural soil, such as softening upon contact with water and biodegradation. A composite organic bonding network is constructed using these three raw materials in specific amounts. Among them, the pregelatinized starch dissolves and gelatinizes rapidly upon contact with water, producing extremely high viscosity and providing high early strength during the drying process. Cellulose dissolves in water to form a colloidal substance, which can efficiently retain water and greatly delay water evaporation, providing sufficient time and environment for the curing of yellow clay, reducing the risk of cracking during the curing of the ant nest simulation material, and providing it with a certain degree of toughness and bending resistance. The adhesive powder can improve the impact resistance and toughness of the cured yellow clay, enhance internal bonding force, and enhance the mechanical strength of the simulation material. Therefore, using a specific ratio of cellulose, adhesive powder, and pregelatinized starch can better simulate the strength of the nest after the ant secretions have solidified, and it softens and disintegrates rapidly upon contact with water, exhibiting high permeability.

[0011] Preferably, the amount of curing agent used is 4 wt% of the mass of yellow clay.

[0012] By adopting the technical scheme, the curing agent is mixed into the yellow clay in a low amount, the appearance of the prepared simulation material is still very close to the original clay, the color is not obviously changed due to the addition of a large amount of organic matter, the density is small, the simulation material is closer to the true soil bulk density, the yellow clay particles can form effective bonding, the loose powder is changed into a solid block with sufficient strength, the solid block can be picked up and transported without falling apart, can bear its own weight and even certain external pressure, the stability of the simulation ant nest structure is simulated, and the water reversibility is retained, the simulation material is soaked in water, the material is gradually softened and disintegrated, and finally becomes mud again, so that the seepage process in nature is simulated.

[0013] Preferably, the water content of the polymeric composite ant nest material is 20-20.5%.

[0014] By adopting the technical scheme, the polymeric composite ant nest material provides a good environment for the dissolution, migration and reaction of ions when the water content is 20-20.5%, the aluminate ions, silicate ions and sulfate ions can be better dissolved and diffused, the collision opportunities of the ions with other reactant ions such as calcium ions are increased, and sufficient and stable reactant sources are provided for the generation of C-A-H, C-S-H and AFt; a higher water content can promote the cementation reaction, but more water and slower drainage can change the compactness of the colloid after forming, and the viscosity of the mixture increases, so that the material sample edge is damaged due to adhesion during demolding, structural defects are caused, the interface structure and splitting strength are affected, and the water content is too low, so that the reaction between the curing agent and the yellow clay is incomplete, internal gaps are formed, the material structure is loose, and the mechanical properties are adversely affected.

[0015] Preferably, the water content of the yellow clay is 16-20%, the dry density is 1.5-1.75 g / cm 3 , the liquid limit is 40-45%, the plastic limit is 15-18%, and the plasticity index is 23-27.

[0016] By adopting the technical scheme, the water content, dry density and other parameters of the yellow clay can make the ant nest material have good plasticity, high strength after drying and not easy to crack, so that the ant nest material meets the research requirements.

[0017] Preferably, the content of SiO2 in the yellow clay is 60.22%, the content of Al2O3 is 14.47%, the content of CaO is 10.9%, the content of Na2O is 1.42%, and the content of SO3 is 0.08%.

[0018] Preferably, the content of SiO2 in the cellulose is 1.3%, the content of Al2O3 is 0.10%, and the content of CaO is 1.33%. The SiO2 content in the glue powder is 10.4%, the Al2O3 content is 0.15%, and the CaO content is 60.8%; The SiO2 content in the pregelatinized starch is 11.5%, the Al2O3 content is 3.95%, the CaO content is 5.29%, and the SO3 content is 30.7%.

[0019] By adopting the above technical solution, the component content of each raw material is excited by the alkaline substance calcium oxide, the active aluminum can react with the calcium source to generate C-S-H and C-A-H gel materials, providing core strength and rigidity, and the cellulose and glue powder can also provide toughness and crack resistance through water retention, film formation and fiber lapping.

[0020] In the second aspect, the application provides a preparation method of a polymeric composite anthill material, which adopts the following technical solution: A preparation method of a polymeric composite anthill material, comprising the following steps: Mixing cellulose, glue powder and pregelatinized starch, stirring uniformly to prepare a curing agent; Mixing the curing agent and yellow clay uniformly, adding water, stirring for 120-150s to prepare a polymeric composite anthill material.

[0021] By adopting the above technical solution, the cellulose, glue powder and pregelatinized starch are used as the curing agent to bond the yellow clay, and C-S-H, C-A-H gel materials and needle bar-shaped AFt are generated by hydration reaction, which cement the clay particles, fill the pores to form a high-strength skeleton, thereby improving the strength and anti-deformation ability of the soil body; the hydrolysis of the C-A-H and C-A-H gel materials formed in the excess water is like decomposition, losing the core cementing ability, at the same time, the gypsum and ettringite are dissolved, and the clay is expanded and damaged by water, destroying the porous structure, resulting in the softening and disintegration of the soil body, and the anthill simulation material prepared therefrom is closer to the anthill properties.

[0022] Preferably, the method for preparing the simulation anthill from the polymeric anthill composite material is as follows: The polymeric composite anthill material is prepared into a hollow tubular matrix; The hollow tubular matrix is cured at 20-25℃ for 7d to prepare a hollow tubular skeleton; Potassium formate is filled into the hollow tubular skeleton.

[0023] By adopting the technical scheme, when the simulated ant nest encounters water, because the yellow clay and the curing agent are both hydrophilic materials, water is rapidly absorbed into the pipe wall material through capillary action, almost simultaneously, water enters through the micropores existing in the pipe wall or from the openings at both ends of the pipeline, and contacts the potassium formate filled inside, the potassium formate has extremely high water solubility, starts to dissolve instantaneously, forms a high-concentration salt solution, the dissolved potassium formate solution flows out from the openings of the pipeline and the micropores of the pipe wall, pre-scours out tiny channels on the pipe wall, increases the permeability of the pipe wall, and the potassium formate simulates the loose soil body in the real ant nest that has not been solidified by the secretion, which is washed away first when encountering water, leading to structural instability, as water gradually penetrates, the hollow tubular skeleton gradually softens and expands, the structural strength and cohesion rapidly decrease, thereby losing sufficient strength and being unable to maintain its own geometric shape, overall collapse or local burst occurs, and finally completely dissolves in dispersion.

[0024] The real ant nest is composed of nest wall solidified by ant saliva and secretion and internal loose backfill soil, the nest wall is simulated by the polymeric composite ant nest material, the loose and easily soluble soil body in the ant nest structure is simulated by potassium formate, and the internal loose soil body becomes heavy and increases in flowability after absorbing water, generates lateral pressure on the nest wall, so that the nest gradually produces acid partial channel collapse, and finally leads to the failure of the whole structure, therefore, the application can simulate the destruction process of the real ant nest in the dam body by using the polymeric ant nest material and potassium formate, quantitatively reveal the mechanism of how the ant nest induces and accelerates the instability and destruction of water-based engineering infrastructure through a controllable, visible and repeatable physical model, and provide scientific basis and key technical support for disaster prevention and reduction.

[0025] Preferably, the curing and forming temperature is 20 DEG C.

[0026] By adopting the technical scheme, the solubility of the minerals containing aluminum, silicon and sulfur participating in the reaction is in a relatively ideal state at this temperature, and aluminum ions, silicon ions and sulfate ions can be continuously and stably released, so that the appropriate curing temperature can make the internal structure of the material relatively stable, the stress decay is relatively flat, and high compressive strength is embodied, and if the curing temperature is too high, the rapid change of water due to high-temperature acceleration of water migration and evaporation destroys the uniformity of the original structure, the intergranular force and the stability of the cementing structure in the material are weakened, and the material is more likely to suddenly lose stability and be destroyed under stress, and more obvious brittle change is presented.

[0027] In summary, the application has the following beneficial effects: 1. The application uses cellulose, glue powder and pregelatinized starch as curing agent in a specific ratio, adds the curing agent to the yellow clay in a certain amount, and generates C-S-H and C-A-H gel materials and needle-like AFt substances through pozzolanic reaction and hydration reaction. The gel materials can fill and cement the fine yellow clay particles into a whole, and the needle-like AFt substances can further connect these cemented blocks to form a high-strength skeleton structure, thus obtaining an ant nest material with good strength and permeability, which is similar to the clay component in nature, has high strength, good water solubility and good permeability, and meets the selection requirements of the ant nest material in model tests, thus truly reproducing the process of soil and water loss caused by the ant nest system.

[0028] 2. The unconfined compressive strength and splitting tensile strength of the ant nest material prepared by mixing the yellow clay with 4wt% of the curing agent and controlling the water content of the raw material to 20% and curing at 20°C are optimal, and the unconfined compressive strength is 3.53 times that of the yellow clay, and the splitting strength is 3.14 times that of the yellow clay. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 Figure 4 is a graph of the unconfined axial stress-strain relationship of the ant nest material with a water content of 20% after curing at 20°C. Figure 1 In the figure, G-A20% is Example 1, G-B20% is Comparative Example 1, G-C20% is Comparative Example 2, G-D20% is Comparative Example 3, G-E20% is Comparative Example 4, and G-F20% is Comparative Example 5.

[0030] Figure 2 Figure 5 is a graph of the unconfined axial stress-strain relationship of the ant nest material with a water content of 20% after curing at 50°C. Figure 1 In the figure, G-A20% is Example 1, G-B20% is Comparative Example 1, G-C20% is Comparative Example 2, G-D20% is Comparative Example 3, G-E20% is Comparative Example 4, and G-F20% is Comparative Example 5.

[0031] Figure 3 Figure 6 is a graph of the splitting stress-strain relationship of the ant nest material with a water content of 20% after curing at 20°C. Figure 1 In the figure, C-A20% is Example 1, C-B20% is Comparative Example 1, C-C20% is Comparative Example 2, C-D20% is Comparative Example 3, C-E20% is Comparative Example 4, and C-F20% is Comparative Example 5.

[0032] Figure 4 Figure 7 is a graph of the splitting stress-strain relationship of the ant nest material with a water content of 20% after curing at 50°C. Figure 1(G-A 20% is Example 1, G-B 20% is Comparative Example 1, G-C 20% is Comparative Example 2, G-D 20% is Comparative Example 3, G-E 20% is Comparative Example 4, G-F 20% is Comparative Example 5).

[0033] Figure 5 XRD diffraction patterns of ant nest materials at different curing temperatures and moisture contents when the curing agent content is 4wt%.

[0034] Figure 6 SEM images of ant nest materials at different curing temperatures and moisture contents when the curing agent content is 4wt%.

[0035] Figure 7 This is a simulation diagram of the permeation effect of materials used to simulate ant nests. Detailed Implementation

[0036] The present application will be further described in detail below with reference to the embodiments. Example

[0037] The raw materials selected in the following examples are as follows: Yellow clay was selected from the Loess Plain of Yuncheng, Shanxi Province, with a sampling depth of 2-3m. The optimal moisture content of this yellow clay is 18.6%, and the maximum dry density is 1.73g / cm³. 3 The liquid limit was 43.2%, the plastic limit was 17.6%, and the plasticity index was 25.6. The cellulose was a slightly yellow powder, the gum powder and pregelatinized starch were white powders, and the water was tap water. The oxide composition of yellow clay and cellulose, gum powder and pregelatinized starch is shown in Table 1.

[0038] Table 1. Mass percentage of each oxide component in yellow clay and curing agent raw materials. Example 1: A polymeric composite ant nest material containing 100g of yellow clay, a curing agent and water. The amount of curing agent is 4wt% of the mass of yellow clay, and the amount of water added makes the moisture content of the polymeric composite ant nest material 20%. The curing agent contains cellulose, adhesive powder and pregelatinized starch in a mass ratio of 1:1:2.

[0039] The preparation method of the above-mentioned polymer composite ant hole material includes the following steps: A curing agent is prepared by mixing cellulose, adhesive powder and pregelatinized starch and stirring evenly. Mix the curing agent and yellow clay evenly, add water, and stir for 120 seconds to prepare a polymer composite ant nest material.

[0040] Examples 2-3: A polymeric composite ant nest material, differing from Example 1 in that the amount of curing agent used is 4.5 wt% of the mass of yellow clay.

[0041] Example 3: A poly composite anthill material, which is different from example 1 in that the amount of curing agent is 5wt% of the mass of the yellow clay.

[0042] Example 4: A poly composite anthill material, which is different from example 1 in that the mass ratio of cellulose, glue powder and pre-gelatinized starch in the curing agent is 1:1:3.

[0043] Example 5: A poly composite anthill material, which is different from example 1 in that the mass ratio of cellulose, glue powder and pre-gelatinized starch in the curing agent is 1:2:3.

[0044] Example 6: A poly composite anthill material, which is different from example 1 in that the mass ratio of cellulose, glue powder and pre-gelatinized starch in the curing agent is 1:2:2.

[0045] Comparative example Comparative example 1: A poly composite anthill material, which is different from example 1 in that the amount of curing agent is 6wt% of the mass of the yellow clay.

[0046] Comparative example 2: A poly composite anthill material, which is different from example 1 in that the amount of curing agent is 7wt% of the mass of the yellow clay.

[0047] Comparative example 3: A poly composite anthill material, which is different from example 1 in that the amount of curing agent is 8wt% of the mass of the yellow clay.

[0048] Comparative example 4: A poly composite anthill material, which is different from example 1 in that the amount of curing agent is 10wt% of the mass of the yellow clay.

[0049] Comparative example 5: A poly composite anthill material, which is different from example 1 in that no curing agent is added, only yellow clay.

[0050] Comparative example 6: A poly composite anthill material, which is different from example 1 in that the water content of the poly composite anthill material is 21%.

[0051] Comparative example 7: A poly composite anthill material, which is different from example 1 in that the amount of curing agent is 6wt%, and the water content of the poly composite anthill material is 21%.

[0052] Comparative example 8: A poly composite anthill material, which is different from example 1 in that the amount of curing agent is 7wt%, and the water content of the poly composite anthill material is 21%.

[0053] Comparative example 9: A poly composite anthill material, which is different from example 1 in that the amount of curing agent is 8wt%, and the water content of the poly composite anthill material is 21%.

[0054] Comparative Example 10: A poly-composite anthill material, which is different from Example 1 in that the content of the curing agent is 10 wt%, and the water content of the poly-composite anthill material is 21%.

[0055] Comparative Example 11: A poly-composite anthill material, which is different from Example 1 in that the content of the curing agent is 0, and the water content of the poly-composite anthill material is 21%.

[0056] Comparative Example 12: A poly-composite anthill material, which is different from Example 1 in that the water content of the poly-composite anthill material is 21%.

[0057] Comparative Example 13: A poly-composite anthill material, which is different from Example 1 in that the content of the curing agent is 6 wt%, and the water content of the poly-composite anthill material is 21%.

[0058] Comparative Example 14: A poly-composite anthill material, which is different from Example 1 in that the content of the curing agent is 7 wt%, and the water content of the poly-composite anthill material is 21%.

[0059] Comparative Example 15: A poly-composite anthill material, which is different from Example 1 in that the content of the curing agent is 8 wt%, and the water content of the poly-composite anthill material is 21%.

[0060] Comparative Example 16: A poly-composite anthill material, which is different from Example 1 in that the content of the curing agent is 10 wt%, and the water content of the poly-composite anthill material is 21%.

[0061] Comparative Example 17: A poly-composite anthill material, which is different from Example 1 in that the content of the curing agent is 0, and the water content of the poly-composite anthill material is 21%.

[0062] Performance detection test In the hydraulic simulation test, the anthill damage mainly has three modes: seepage damage, water seepage along the anthill to wash away the particles; tensile failure, thin-walled cracking and collapse due to insufficient tensile resistance under confining pressure and water pressure; local crushing. The unconfined compression test provides shear strength and quality control reference, and the splitting test gives tensile strength, which respectively corresponds to crushing and tensile cracking, and the method is simple, reliable and economical.

[0063] I. Unconfined compressive strength detection: The poly-composite anthill material is prepared according to the method in Examples 1-3 and Comparative Examples 1-5, and is cured at 20℃ for 7d; the curing temperature is adjusted to 50℃, and cured for 7d as a control; the unconfined compressive strength of the poly-composite anthill material prepared under the curing conditions of 20℃ and 50℃ is detected, the detection method is as follows, and the detection results are recorded in Table 2, the unconfined axial stress-strain process after 20℃ curing is as follows: Figure 1As shown, the unconfined axial stress-strain process after 50 °C curing is completed as shown in FIG. 2. Figure 2 As shown in FIG. 1.

[0064] The electronic universal testing machine of Guangdong Aiseli Instrument Technology Co., Ltd. is used, the speed of 1 mm / min is added, the maximum pressure P of the unconfined sample failure is recorded, and the unconfined compressive strength of the sample is calculated according to the following formula: UCS = P / A, wherein UCS is the unconfined compressive strength of the sample, MPa; P is the pressure when the sample is destroyed, N; and A is the cross-sectional area of the sample, mm 2 .

[0065] Table 2 Unconfined compressive strength test It can be seen from the detection data in Table 2 that when the water content is 20%, the unconfined compressive strength of the comparative example 5 without adding a curing agent and only adding a simple yellow clay is 2.47 MPa and 1.08 MPa when cured at 20 °C and 50 °C, respectively. In comparative examples 2-4, the unconfined compressive strength is significantly improved after adding different amounts of curing agents. Among them, the unconfined compressive strength is the highest after adding 4 wt% of the curing agent, which is 8.72 MPa and 5.03 MPa, respectively, and is increased by 253% and 366% compared with comparative example 5, respectively. This shows that the polymeric composite ant nest material can improve the curing strength when the water content is 20%.

[0066] It is shown in comparative examples 6-11 that when the water content of the polymeric composite ant nest material is 21%, the unconfined compressive strength reaches the maximum value in comparative example 6 when the curing agent content is 4%, and the unconfined compressive strength is 7.88 MPa and 6.43 MPa when cured at 20 °C and 50 °C, respectively. When the curing agent content is increased to 10 wt% in comparative example 10, the unconfined compressive strength of the polymeric composite ant nest material after curing at 20 °C and 50 °C is reduced to 6.11 MPa and 3.83 MPa, respectively. Compared with comparative example 11 without adding a curing agent, the unconfined compressive strength after curing at 20 °C is increased by 85%, and the unconfined compressive strength after curing at 50 °C is increased by 3%.

[0067] In Comparative Examples 12-17, when the moisture content of the polymeric composite anthill material was 22% and the curing agent dosage was 4wt%, the unconfined compressive strength reached its maximum value, reaching 7.64MPa and 9.06MPa after curing at 20℃ and 50℃ for 7 days. When the curing agent dosage increased from 4wt% in Comparative Example 12 to 10wt% in Comparative Example 16, the unconfined compressive strength of the polymeric composite anthill material after curing at 20℃ and 50℃ decreased to 4.71MPa and 5.77MPa, respectively. Compared with Comparative Example 17 without curing agent, it was still improved by 31.2% and 184%, respectively. However, the unconfined compressive strength of Comparative Example 16 cured at 50℃ was significantly higher than that cured at 20℃.

[0068] With a curing agent dosage of 4 wt% and cured at 20°C, the unconfined compressive strengths after curing at moisture contents of 20%, 21%, and 22% were 8.72 MPa for Example 1, 7.88 MPa for Comparative Example 6, and 7.64 MPa for Comparative Example 12, respectively. These strengths represent increases of 253%, 139%, and 113% compared to 2.47 MPa in Comparative Example 5, 3.3 MPa in Comparative Example 11, and 3.59 MPa in Comparative Example 17, respectively. At 50°C and with a curing agent content of 4 wt%, the unconfined compressive strengths of Examples 1, 6, and 12 were 7.08 MPa, 6.43 MPa, and 9.06 MPa, respectively, when the moisture contents were 20%, 21%, and 22 wt%. These values ​​represented increases of 555%, 72.8%, and 346% compared to 1.08 MPa in Comparative Example 5, 3.72 MPa in Comparative Example 11, and 2.03 MPa in Comparative Example 17.

[0069] It can be seen that under the condition that the water content of the polymer composite ant hole material is 22%, high temperature can accelerate gelation and molecular diffusion, promote the formation of a more uniform micro gel system, and early drainage reduces pore water pressure, so that the load is borne more by the particle skeleton and cementation structure, thus showing the phenomenon of increased strength.

[0070] Depend on Figure 1 As can be seen from the unconfined stress-strain relationship diagram, when curing yellow clay with a curing agent containing cellulose, adhesive powder and pregelatinized starch, the axial stress-strain process is divided into three stages: the compaction stage, in which the stress rises slowly with the increase of axial strain, the reaction pores are compressed, the interparticle gaps are reduced and the volume shrinks; the elastic stage, in which the stress and strain are approximately linear, the soil skeleton bears the external load and responds elastically; and the failure stage, in which the stress reaches its peak and then drops sharply with the strain, the surface structure becomes unstable and loses strength.

[0071] Figure 1The results show that the different curing agent addition amount of the ant nest material, the water content is 20%, and the curing is carried out at 20 DEG C, the peak stress of the comparative example 5 without adding curing agent is 2.47 MPa, the failure strain is 0.92%, the strength of example 1 is greater than that of other comparative examples, and is 3.53 times of that of comparative example 5. It can be seen that the internal structure is relatively stable at 20 DEG C, the water content of the ant nest material is 20%, the water and the adjacent interaction is in an optimal state, the stress attenuation is relatively flat, and the better compressive strength is embodied.

[0072] Figure 2 The axial stress-strain curves of the different curing agent addition amount at 50 DEG C and the water content of 20% are similar to the strength change of the curing at 20 DEG C, and all have higher stress values when the curing agent addition amount is 4wt%, and the peak stress of each addition amount curve at 50 DEG C is obviously lower than that at 20 DEG C.

[0073] It can be seen that the high temperature accelerates the migration and evaporation of water, the rapid change of water destroys the uniformity of the original structure, the interaction between the particles in the material and the stability of the cementing structure are weakened, the material is more prone to sudden instability and damage under stress, and the more obvious brittleness change is shown. The unconfined axial stress-strain change rule of the cured yellow clay with 20% water content at high and low temperatures is also applicable to the curing conditions of 21% water content and 22% water content, 20 DEG C and 50 DEG C, and similar trends are shown.

[0074] II. Splitting strength detection: the polymeric composite ant nest material prepared according to the methods in examples 1-3 and comparative examples 1-5 is cured at 20 DEG C for 7d; the curing temperature is adjusted to 50 DEG C, and the curing is carried out for 7d, as a control, the splitting strength of the polymeric composite ant nest material prepared under the curing conditions of 20 DEG C and 50 DEG C is detected, the detection method is as follows, and the detection results are recorded in table 3, the splitting stress-strain process after the curing at 20 DEG C is as shown in Figure 3 , and the splitting stress-strain process after the curing at 50 DEG C is as shown in Figure 4 .

[0075] The loading process is carried out according to 'Highway Engineering Inorganic Binder Stabilized Material Test Regulations' (JTGE51-2009), an electronic universal testing machine of Guangdong Aiseli Instrument Science and Technology Co., Ltd. is used, the loading speed is 0.8mm / min, the failure strength f of the splitting sample is recorded, and the splitting tensile strength is calculated according to the following formula: f = 2p / πld, in the formula, f is the splitting strength of the sample, MPa; p is the load acting on the cylindrical sample, kN; l is the height of the cylindrical sample, m; and d is the diameter of the cylindrical sample, m.

[0076] Table 3 Splitting strength test As can be seen from the data in Table 3, when the water content of the polymeric composite ant nest material is 20%, the splitting strength of the comparative example 5 without the addition of the curing agent is 0.09 MPa and 0.49 MPa respectively when cured at 20°C and 50°C, the splitting strength of the polymeric composite ant nest material reaches the maximum value when the content of the curing agent is 4wt%, and the splitting strength is 0.49 MPa and 0.88 MPa respectively after curing at 20°C and 50°C, when the content of the curing agent reaches 10wt% in the comparative example 4, the splitting strength of the polymeric composite ant nest material after curing at 20°C and 50°C is reduced to 0.12 MPa and 0.51 MPa respectively, compared with the comparative example 5 without the addition of the curing agent, the splitting strength at 20°C and 50°C in the comparative example 4 is still increased by 33% and 4.1%, which shows that the diffusion and reaction of the curing agent is slow at low temperature, the strength increases slowly and the upper limit is low, the activity of the curing agent is increased at high temperature, the diffusion and moisture migration are accelerated, the interface interaction of the hydrogen bond and the van der Waals force is promoted, the density is increased, and then the splitting strength is increased.

[0077] The water content of the polymeric composite ant nest material in the comparative examples 6-11 is 21%, the splitting strength of the polymeric composite ant nest material reaches the maximum value when the content of the curing agent is 4wt%, and the splitting strength is 0.37 MPa and 1.14 MPa respectively after curing at 20°C and 50°C, when the content of the curing agent reaches 10wt% in the comparative example 10, the splitting strength is reduced to 0.13 MPa and 0.48 MPa respectively after curing at 20°C and 50°C, compared with the comparative example 11 without the addition of the curing agent, the comparative example 10 is still increased by 1.5% and 153%. When the moisture is increased at 50°C, the migration and reaction are more complex, the cementing effect of the curing agent is greatly affected by the drainage rate, the pre-gelatinized starch is more fully gelatinized when the water content is 21%, but the moisture is slightly slower, the density of the colloid after molding is different from that when the water content is 20%, and then the splitting strength is affected, when the water content is 20%, the thicker interface water film increases the difficulty of the combination of the curing agent and the matrix clay, and the strength increase is limited.

[0078] The splitting strength of the material with the water content of 22% in the comparative examples 12-17 is detected, the splitting strength is 0.44 MPa and 0.81 MPa respectively after curing at 20°C and 50°C when the content of the curing agent is 4wt%, compared with the comparative example 17 without the addition of the curing agent, the splitting strength is increased by 214.3% and 145.5% respectively.

[0079] When the curing agent addition amount is 4wt%, the curing temperature is 20℃, and the water content is 20%, 21% and 22%, the splitting strength of the ant nest material after curing is 0.49MPa for Example 1, 0.37MPa for Comparative Example 6, and 0.44MPa for Comparative Example 12, which is increased by 444%, 185% and 224% respectively compared with Comparative Examples 5, 11 and 17; when the curing temperature is 50℃ and the curing agent addition amount is 4wt%, the splitting strength of Example 1 is 0.88MPa, the splitting strength of Comparative Example 6 is 1.14MPa, and the splitting strength of Comparative Example 12 is 0.81MPa, which is increased by 80%, 500% and 145% respectively compared with Comparative Examples 5, 11 and 17. When the curing temperature is 50℃, the splitting strength is better due to the temperature promoting the formation of microstructure inside the material. However, considering the mechanical properties of the material and the performance requirements of most engineering materials, the performance of the material cured at 20℃ can meet the engineering requirements, and considering environmental protection and resource utilization, the curing temperature of 20℃ is better.

[0080] Therefore, higher water content can promote cementation reaction, but more water and slower drainage can change the compactness of the colloidal form, thereby affecting the interface structure and splitting strength. The difference in water migration rate at different water contents can change the reaction process of the curing agent and the interface formation. Therefore, considering economic benefits and actual engineering conditions, the ant nest material prepared by curing at 20℃, with a curing agent addition amount of 4wt% and a water content of 20% can meet the demand for ant nest simulation materials.

[0081] Figure 3 and Figure 4 The middle curve shows four stages of compaction, elasticity, yield and post-peak failure, which are respectively represented by the initial crack compaction curve, the linear growth of elasticity, the yield with microcrack expansion, and the stress drop after the peak and no strain softening.

[0082] Figure 3 When the water content is 20% and the curing temperature is 20℃, the peak stress of Comparative Example 5 without adding curing agent is 0.14MPa, and the failure strain is 0.32%. The peak splitting strength of Example 1 is 0.44MPa, which is 3.14 times that of Comparative Example 5. The strength of Example 1 is greater than that of other comparative examples, indicating that at a water content of 20%, a curing agent with a dosage of 4% can improve the failure strain and deformation resistance of the ant nest material and increase the tensile strength. When cured at 20℃, the splitting stress-strain curves of different dosages differ significantly. Some curves rapidly decrease after reaching high stress at small strain, showing brittleness, and some curves rise and fall relatively gently.

[0083] Figure 4The peak stress of Comparative Example 5 is 0.33 MPa, and the failure strain is 1.51%, the splitting strength of Example 1 is 0.81 MPa, which is 2.45 times of Comparative Example 5, and it has similar strength change with the test of curing at 20℃, and it shows that when the curing agent content is 4wt%, it has a higher stress value, the peak stress of curing at 50℃ is more obvious than that of curing at 20℃, and the brittleness changes obviously, when curing at 50℃, the overall change of stress curve is gentle and concentrated, the peak strain of some test pieces increases, the peak value and the slope of the falling slope are different from those of curing at 20℃, which shows that the temperature rise significantly affects the splitting mechanical properties, the ductility of the material improves at high temperature, and the stress-strain development is more gentle. Under the conditions of 20% moisture content and high and low temperature curing, the stress-strain change rule of the splitting strength of the cured clay with the curing agent is also applicable to the conditions of 21% and 22% moisture content, 20℃ and 50℃ curing, and shows similar trends.

[0084] III. XRD test and SEM analysis: The polymeric composite anthill material was prepared according to the method in Example 1 and Comparative Examples 1-5, as a control, the curing temperature was adjusted to 50℃, and cured for 7d. The polymeric composite anthill material prepared under the conditions of curing at 20℃ and 50℃ was detected by Rigaku / SmartLab, with a scanning speed of 5° / min and a scanning angle of 10-80°, and a scanning electron microscope (China-Guojishili Quantum-SEM5000X) was used to detect SEM. The XRD test results are shown in Figure 5 The SEM images are shown in Figure 6 .

[0085] As can be seen from Figure 5 , in addition to the diffraction peaks of SiO2, Al2O3 and CaO, there is a diffraction peak of FAt at 2θ = 22.3°; there are weak diffraction peaks of C-A-H gel between 2θ = 25-30°, and weak diffraction peaks of C-S-H gel between 2θ = 35-40°.

[0086] As can be seen from the above, the curing agent containing cellulose, glue powder and pre-gelatinized starch can cure the yellow clay, and the structure of the cured soil formed is mainly mixed with crystals and gels. During the reaction of the curing agent, crystal precipitates are produced, at the same time, the soluble substances in the system graft Ca 2+ exchange and charge balance, respectively, to form C-S-H and C-A-H. In addition, the gel formed by the reaction can also fill the pores in the polymer network, thereby constructing a more compact polymer matrix, and Figure 1The C-A-H, C-S-H and AFt diffraction peak enhancement effect of the multi-polymer composite ant nest material is more obvious than other materials when the water content is 20%, the curing temperature is 20°C, and the curing agent content is 4%. Because at 20°C, the solubility of the minerals containing aluminum, silicon and sulfur participating in the reaction is in a relatively ideal state, and the aluminum ions, silicon ions and sulfate ions can be continuously and stably released, the water content of 20% is a suitable water environment, which provides a good environment for the dissolution, migration and reaction of ions, so that the aluminate ions, silicate ions and sulfate ions can be better dissolved and diffused, and the collision opportunities of other reactant ions such as calcium ions are increased, so as to provide sufficient and stable reactant sources for the generation of C-A-H, C-S-H and AFt. Therefore, when the water content of the multi-polymer composite ant nest material is 20%, the curing agent content is 4wt%, and the curing temperature is 20°C, the diffraction peak intensity is more obvious than other groups.

[0087] From Figure 6 (a) and Figure 6 (b), it can be seen that under the water content of 20%, when the curing temperature is 20°C and 50°C, a large amount of flocculent C-A-H, C-S-H and needle-like AFt appear on the surface of the cured yellow clay; from Figure 6 (c) and Figure 6 (d), it can be seen that under the water content of 21%, when the curing temperature is 20°C and 50°C, the flocculent C-A-H, C-S-H and needle-like AFt appearing on the surface of the cured yellow clay are reduced compared with the cured yellow clay with water content of 20%, and the soil particle amount increases; from Figure 6 (e) and Figure 6 (f), it can be seen that under the water content of 22%, when the curing temperature is 20°C, the flocculent C-A-H, C-S-H and needle-like AFt appearing on the surface of the cured yellow clay are reduced compared with the water content of 20% and 21%, and the unreacted soil particle volume increases, and when the curing temperature is 50°C, a large amount of aggregated needle-like AFt appears on the surface of the cured clay, and the flocculent C-A-H and C-S-H are contained in the internal and external gaps.

[0088] It can be seen that when the curing agent content is 4wt%, the curing agent has good bonding effect with soil particles under suitable moisture conditions, so that the strength is higher. When the curing agent content is 4wt% and the curing is carried out at 50℃, a large amount of AFt and flocculent gel are generated at 22% moisture content, and the soil particles are less. This is because high temperature can increase the kinetic energy of reactant molecules, accelerate molecular motion, increase collision frequency, and sufficient water can ensure the sufficient dissolution and migration of reactant ions, promote the growth and aggregation of AFt crystals, and at the same time affect the local environment of the reaction system, which is beneficial to the formation of flocculent material. Therefore, when the curing agent content is 4wt% and the curing is carried out at 20℃, the overall compactness of the cured yellow clay and the generated product are better at 20% moisture content.

[0089] III. Seepage effect monitoring: Take the swelling material (French fries), PAA material with a concentration of 80%, PVA water-soluble film + potassium formate, and the cured yellow clay prepared in Example 1 to carry out soil permeability test. The test method is as follows: place the experimental soil (ordinary soil with a moisture content of 12%) in the model box, bury the four different ant nest simulation materials on both sides of the model box, fill the soil and compact after the ant nest simulation materials are placed, and then store water. The placement method of the swelling material sample is: stack the French fries neatly. The placement method of the PVA water-soluble film and potassium formate sample is: lay the PVA water-soluble film on one side of the experimental soil, and then place a layer of potassium formate on the PVA film. The method for preparing the simulation ant nest as a sample in Example 1 of the application is as follows: prepare a hollow tubular base body (the diameter and wall thickness of the hollow tubular base body are not specifically limited, and are designed and adjusted according to the scale of the target ant nest, the biological characteristics of the ant species, or the actual working condition of the simulated dam body), cure the hollow tubular base body at 20℃ for 7 days to obtain a hollow tubular skeleton, fill the hollow tubular skeleton with potassium formate, and then place it on one side of the compacted experimental soil. Observe the permeability of each material continuously, and the seepage effect of the ant nest simulation material is as shown in Figure 7

[0090] Figure 7 ​As shown in the figure, the ant-hill material prepared in Embodiment 1 of the present application has the most remarkable permeation effect, rapidly dissolves and forms a permeation channel after meeting water, the permeation performance of the PVA water-soluble film composite potassium formate material is the second, the permeation time is delayed by about 5 minutes compared with Embodiment 1, the swelling material and the PAA material have poor permeation effect, and only weak permeation phenomenon is observed after 3-5 days of water storage, the reason is that the surface of the swelling material is brittle, easy to block the seepage channel after swelling, and the swelling material is easy to break and has low strength during compaction, the PAA is a superabsorbent resin, expands into a continuous gel network to block the pores, the PVA film + potassium formate has good permeability after dissolving, but is easy to deform during compaction; the cellulose, glue powder and pre-gelatinized starch prepared in the present application are used to fill and cement the soil particles, the formed product is stable, the potassium formate is dissolved to form a stable permeation channel after meeting water, and the solidified soil is loose and soft after soaking, and the ant-hill model material can better fit the actual ant-hill.

[0091] The specific embodiments are only an explanation of the present application, and are not a limitation of the present application, and those skilled in the art can make modifications to the embodiments without creative contribution according to the needs after reading the present specification, and the modifications are protected by the patent law as long as in the scope of the claims of the present application.

Claims

1. A polymeric composite anthill material, characterized in that, The raw materials of the polymer composite ant nest material include yellow clay, curing agent and water. The amount of curing agent is 4-5 wt% of the mass of yellow clay. The curing agent mass ratio is 1:1-2:2-3 and includes cellulose, gum powder and pregelatinized starch.

2. The polymeric composite anthill material according to claim 1, characterized in that: The mass ratio of cellulose, gum powder and pregelatinized starch in the curing agent is 1:1:

2.

3. The polymeric composite anthill material according to claim 1, characterized in that: The amount of curing agent used is 4 wt% of the mass of yellow clay.

4. The polymeric composite anthill material according to claim 1, characterized in that: The moisture content of the polymer composite ant nest material is 20-20.5%.

5. The polymeric composite anthill material according to claim 1, characterized in that: The yellow clay has a moisture content of 16-20% and a dry density of 1.5-1.75 g / cm³. 3 The liquid limit is 40-45%, the plastic limit is 15-18%, and the plasticity index is 23-27.

6. The polymeric composite anthill material according to claim 1, characterized in that: The yellow clay contains 60.22% SiO2, 14.47% Al2O3, 10.9% CaO, 1.42% Na2O, and 0.08% SO3.

7. The polymeric composite anthill material according to claim 1, characterized in that: The cellulose contains 1.3% SiO2, 0.10% Al2O3, and 1.33% CaO. The adhesive powder contains 10.4% SiO2, 0.15% Al2O3, and 60.8% CaO. The pregelatinized starch contains 11.5% SiO2, 3.95% Al2O3, 5.29% CaO, and 30.7% SO3.

8. The method for preparing the polymeric composite anthill material according to claims 1-7, characterized in that: Includes the following steps: A curing agent is prepared by mixing cellulose, adhesive powder and pregelatinized starch and stirring evenly. Mix the curing agent and yellow clay evenly, add water, and stir for 120-150 seconds to prepare a polymer composite ant nest material.

9. The method for preparing the polymeric composite anthill material according to claim 8, characterized in that: The method for preparing simulated ant nests using the polymeric ant nest material is as follows: The polymeric ant hole material is made into a hollow tubular matrix; A hollow tubular matrix was cured at 20-25℃ for 7 days to obtain a hollow tubular skeleton. Potassium formate was filled into the hollow tubular framework.

10. The method for preparing the polymeric composite anthill material according to claim 9, characterized in that: The curing and molding temperature is 20℃.

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