Simulation material and method for water abundance heterogeneity of unconsolidated rock aquifer

Abstract

This invention pertains to mine hydrogeology, specifically disclosing a simulation material and method for the heterogeneity of water-bearing capacity in loose rock aquifers. The simulation material introduces filling materials to optimize the pore structure of the low-permeability background layer, improves the continuous permeability variation capability of the medium-permeability transition zone by optimizing particle size distribution, and enhances the structural stability and pore connectivity of the high-permeability water-bearing zone by adding cementing materials and multi-scale coarse particles. This allows the three types of materials to form a stable spatial permeability difference while maintaining their respective permeability characteristics. The aquifer physical model constructed using the above materials can more realistically simulate the heterogeneous distribution characteristics of the coexistence of low-permeability background zones, medium-permeability transition zones, and high-permeability water-bearing zones in natural aquifers, and can realize the dynamic evolution of dominant seepage channels in experiments, thereby significantly improving the realism of physical simulation experiments.

Description

Technical Field

[0001] This invention belongs to the field of mining hydrogeology technology, specifically relating to a simulation material and method for the heterogeneity of water-bearing capacity in loose rock aquifers. Background Technology

[0002] The water-bearing capacity of loose rock aquifers usually exhibits obvious spatial heterogeneity. Affected by factors such as sedimentary environment, particle size distribution, degree of cementation, and local pore morphology, there are both locally strong water-bearing areas and weak water-bearing areas in the aquifer. The groundwater seepage process shows significant spatial differences in runoff intensity.

[0003] In existing indoor physical simulation tests, the materials used to simulate loose rock aquifers are usually composed of sand-gypsum or sand-cement materials with the same overall proportions. Their permeability is spatially consistent, making it difficult to accurately reflect the local differences in water-bearing capacity and the non-uniform seepage diffusion characteristics within natural loose rock aquifers. Because of the use of homogeneous materials with the same overall proportions, it is impossible to simulate the rapid propagation of groundwater in localized high-permeability areas and the concentration of dominant seepage, resulting in significant differences between the seepage test results and the actual seepage behavior of underground aquifers.

[0004] While some studies have attempted to simulate permeability differences by altering particle size, these approaches remain at the level of simple stratification or overall gradation changes, lacking the ability to simulate the random distribution of water-rich and non-water-rich zones within the spatial structure of loose rock aquifers. Therefore, there is an urgent need to develop a physical simulation material and method capable of simulating the non-uniform distribution of water-richness in the spatial structure of loose rock aquifers. Summary of the Invention

[0005] In order to solve at least one of the above-mentioned technical problems in the prior art, the present invention provides a simulation material and simulation method for the heterogeneity of water-bearing properties of loose rock aquifers.

[0006] This invention is achieved using the following technical solution: a simulation material for the heterogeneity of water-bearing capacity in loose rock aquifers, comprising: Low-permeability background materials, medium-permeability transition materials, and high-permeability water-rich materials; among them, Low-permeability background materials include fine-particle materials and cementing materials, with fine-particle materials accounting for 60% to 90% of the total mass of low-permeability background materials and cementing materials accounting for 10% to 40% of the total mass of low-permeability background materials; Medium-permeability transition materials include medium-sized particles and cementing materials, with medium-sized particles accounting for 70% to 90% of the total mass of medium-permeability transition materials and cementing materials accounting for 10% to 30% of the total mass of medium-permeability transition materials; High-permeability water-rich materials include coarse-particle materials and soluble particles, with coarse-particle materials accounting for 60% to 90% of the total mass of high-permeability water-rich materials and soluble particles accounting for 10% to 40% of the total mass of high-permeability water-rich materials.

[0007] Preferably, the fine-particle material in the low-permeability background material is one or two of fine sand and silt, and the cementing material in the low-permeability background material is one or two of gypsum and cement.

[0008] Preferably, the low-permeability background material further includes a filler material; the filler material is one or two of bentonite and kaolin, and the amount of the filler material accounts for 10 to 15% of the total mass of the low-permeability background material composed of fine-particle material and cementing material.

[0009] Preferably, the medium-permeability transition material contains medium-sized and coarse sand.

[0010] Preferably, the coarse particles in the high-permeability water-rich material are one or more of coarse sand, ceramsite, gravel, and coal gangue particles; the soluble particles in the high-permeability water-rich material are one or more of salt particles, sucrose particles, glucose particles, and starch particles.

[0011] Preferably, the high-permeability water-rich material also includes a cementing material, the amount of which accounts for 15-20% of the total mass of the high-permeability water-rich material composed of coarse particles and soluble particles.

[0012] Preferably, the low-permeability background material comprises, by mass percentage: 60% silt, 20% gypsum, 10% cement, and 10% bentonite, for constructing a weakly water-rich area; The components of the medium-permeability transition material, by mass percentage, include: 50% fine sand, 20% medium sand, 20% gypsum, and 10% cement, for constructing medium-water-rich areas; The components of the highly permeable water-rich material, by mass percentage, include: 40% coarse sand, 20% ceramsite, 10% salt, 10% sugar granules, 10% gypsum, and 10% cement. These are mixed with water to form irregularly shaped water-rich masses with a particle size of 5–10 cm.

[0013] This invention is achieved using the following technical solution: a method for simulating the heterogeneity of water-bearing capacity in loose rock aquifers, employing simulation materials for the heterogeneity of water-bearing capacity in loose rock aquifers as described in the aforementioned technical solution, comprising: Establish a horizontal aquifer model; According to the preset water-bearing distribution, water-bearing regions are divided for the horizontal aquifer model; among them, the types of water-bearing regions include weak water-bearing regions, moderate water-bearing regions, and strong water-bearing regions. The low-permeability background material, medium-permeability transition material, and high-permeability water-rich material in the simulation material of the heterogeneity of water-bearing capacity of loose rock aquifers are laid alternately in the model box of the flat aquifer model to form a heterogeneous material distribution. After the aquifer is laid, water is continuously injected from one side of the flat aquifer model and water is discharged from the other side. After the flat aquifer model is injected with water, the soluble particles in the high-permeability water-rich material dissolve, the porosity and connectivity of the high-permeability area are improved, and thus a dynamically enhanced water-rich area and dominant seepage channels are formed, realizing the dynamic change simulation of the non-uniform structure of the aquifer's water-richness.

[0014] Preferably, the low-permeability background material, medium-permeability transition material, and high-permeability water-rich material from the simulation material for the heterogeneity of water-bearing capacity in loose rock aquifers are alternately laid in the model box of the flat aquifer model to form a heterogeneous material distribution, including: After the highly permeable water-rich material is mixed evenly, it is prepared into an irregular agglomerated water-rich agglomerated structure, and the particle size of a single water-rich agglomerated ... During the laying of low-permeability background material and medium-permeability transition material, high-permeability water-rich clusters are buried in a random spatial distribution pattern. The spacing between the water-rich clusters is 5 to 20 cm, and the total volume of the water-rich clusters accounts for 20% of the total volume of the flat aquifer model. During the burial process, adjacent water-rich clusters do not come into direct contact with each other to ensure that a discrete spatial non-uniform structure is formed inside the flat aquifer model. After the water-rich mass is buried, low-permeability background material and medium-permeability transition material are laid and lightly compacted to enclose the water-rich mass inside the low-permeability background material, thus forming a spatially heterogeneous aquifer structure in which strong water-rich areas, medium water-rich areas and weak water-rich areas coexist. After the model is laid, it is hammered to compact it and then dried for 48 hours.

[0015] Compared with the prior art, the beneficial effects of the present invention are: This invention provides a simulation material and method for the heterogeneity of water-bearing capacity in loose rock aquifers. The simulation material introduces a filling material to optimize the pore structure of the low-permeability background layer, improves the continuous permeability variation capability of the medium-permeability transition zone by optimizing particle size distribution, and enhances the structural stability and pore connectivity of the high-permeability water-bearing zone by adding cementing materials and multi-scale coarse particles. This allows the three types of materials to form a stable spatial permeability difference while maintaining their respective permeability characteristics. The aquifer physical model constructed using the above materials can more realistically simulate the heterogeneous distribution characteristics of the coexistence of low-permeability background zones, medium-permeability transition zones, and high-permeability water-bearing zones in natural aquifers, and can realize the dynamic evolution of dominant seepage channels in experiments, thereby significantly improving the realism of the physical simulation experiment. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of a simulated material for the water-bearing heterogeneity of loose rock aquifers provided by the present invention.

[0018] Figure 2 This is a flowchart illustrating a method for simulating the heterogeneity of water-bearing capacity in loose rock aquifers provided by the present invention.

[0019] In the figure: 1-High-permeability water-rich material; 2-Medium-permeability transition material; 3-Low-permeability background material. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationships, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should fall within the scope of the technical content disclosed in the present invention. It should be noted that in this specification, relational terms such as "first" and "second" are only used to distinguish one entity from several other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0022] This invention provides an embodiment: such as Figure 1 As shown, the present invention provides a simulation material for the heterogeneity of water-bearing capacity in loose rock aquifers, comprising: a low-permeability background material, a medium-permeability transition material, and a high-permeability water-bearing material; Figure 1 In the text, 1 represents a high-permeability water-rich material, 2 represents a medium-permeability transitional material, and 3 represents a low-permeability background material.

[0023] Low-permeability background materials include fine-particle materials and cementing materials, with fine-particle materials accounting for 60% to 90% of the total mass of low-permeability background materials and cementing materials accounting for 10% to 40% of the total mass of low-permeability background materials.

[0024] Among them, the fine-particle material in the low-permeability background material is preferably one or two of fine sand and silt, and the cementing material is preferably one or two of gypsum and cement; furthermore, a filler material that reduces permeability can also be added, which is one or two of bentonite and kaolin, and its dosage accounts for 10 to 15% of the total mass of the material.

[0025] In embodiments of the present invention, the low-permeability background material is composed of fine particulate material and cementing material, wherein the fine particulate material constitutes the main skeleton of the aquifer simulation material, and the cementing material is used to improve the overall stability and molding performance of the material. This scheme can realize the construction of a low-permeability background layer and meet the basic requirements of physical simulation test.

[0026] The low-permeability background layer constructed using only fine-particle materials and cementing materials has a pore structure mainly controlled by particle size distribution, resulting in relatively poor uniformity of pore distribution and the presence of large interconnected pores in some areas. This leads to a large dispersion in material permeability, which is not conducive to stably simulating the hydraulic characteristics of natural low-permeability aquifers.

[0027] This invention incorporates bentonite and kaolin as filler materials into a low-permeability background material. The fine particles of these materials fill the pores between the coarse particles, further reducing the connectivity of the material pores and improving the uniformity of the overall pore structure. This results in a more stable permeability performance of the low-permeability background layer, thereby improving the simulation effect of the model.

[0028] Medium-permeability transition materials include medium-sized particles and cementing materials, with medium-sized particles accounting for 70% to 90% of the total mass of medium-permeability transition materials and cementing materials accounting for 10% to 30% of the total mass of medium-permeability transition materials.

[0029] In embodiments of the present invention, the medium-permeability transition material is composed of medium-sized particles and cementing materials. By controlling the particle size and degree of cementation, permeability performance between the low-permeability background zone and the high-permeability water-rich zone is achieved.

[0030] However, when only a single-graded particle is used, the internal pore structure of the material is relatively simple, making it difficult to simulate the continuous change in particle gradation and gradual change in permeability in the transition zone of a natural aquifer.

[0031] The medium-permeability transition material in this invention uses a combination of medium and coarse sand gradation, and adjusts the ratio of the two to form a more reasonable pore structure inside the material, so as to achieve a continuous transition of permeability and improve the ability of the transition region to simulate the non-uniform permeability characteristics of natural aquifers.

[0032] High-permeability water-rich materials include coarse-particle materials and soluble particles, with coarse-particle materials accounting for 60% to 90% of the total mass of high-permeability water-rich materials and soluble particles accounting for 10% to 40% of the total mass of high-permeability water-rich materials.

[0033] In embodiments of the present invention, the highly permeable water-rich material is composed of coarse particles and soluble particles. The coarse particles form a large pore space, and the soluble particles gradually dissolve during water injection to form new interconnected pores, thereby simulating local water-rich areas and dominant seepage channels.

[0034] However, when only coarse-grained materials and soluble particles are used to form the water-rich zone, the overall stability of the material is poor. After the soluble particles dissolve, local collapse or particle rearrangement is likely to occur, affecting the stability of the spatial structure of the water-rich zone during the experiment.

[0035] This invention adds an appropriate amount of cementing material to a highly permeable water-rich material to improve the bonding strength between coarse particles, ensuring that soluble particles form water-conducting pores while maintaining overall structural stability. In other embodiments of this invention, materials of different particle sizes, such as ceramsite and coal gangue particles, can be added to the coarse-particle material to form a multi-scale pore structure, so that the water-rich area has both high porosity, strong connectivity and good structural stability, which is closer to the spatial structure characteristics of natural water-rich aquifers.

[0036] The following is a specific embodiment of the present invention: A simulation material for the heterogeneity of water-bearing capacity in loose rock aquifers includes: Low-permeability background materials, medium-permeability transition materials, and high-permeability water-rich materials; among them, The low-permeability background material consists of the following components by mass percentage: 60% silt, 20% gypsum, 10% cement, and 10% bentonite, used to construct a weakly water-rich area. The components of the medium-permeability transition material, by mass percentage, include: 50% fine sand, 20% medium sand, 20% gypsum, and 10% cement, for constructing medium-water-rich areas; The components of the highly permeable water-rich material, by mass percentage, include: 40% coarse sand, 20% ceramsite, 10% salt, 10% sugar granules, 10% gypsum, and 10% cement. These are mixed with water to form irregularly shaped water-rich masses with a particle size of 5–10 cm.

[0037] The simulation material for the heterogeneity of water-bearing capacity in loose rock aquifers, as described in this invention, can simulate the spatial heterogeneity of water-bearing capacity in such aquifers, allowing for the coexistence of locally strong and weak water-bearing zones. It can also simulate dominant seepage channels to reflect strong groundwater runoff and the dynamic changes in aquifer permeability. The materials used are widely available, low in cost, and simple to prepare, making it suitable for indoor physical simulation studies of seepage in heterogeneous aquifers.

[0038] This invention optimizes the pore structure of the low-permeability background layer by introducing filling materials, improves the continuous permeability variation capability of the medium-permeability transition zone by optimizing particle size distribution, and enhances the structural stability and pore connectivity of the high-permeability water-rich zone by adding cementing materials and multi-scale coarse particles. This allows the three types of materials to form a stable spatial permeability difference while maintaining their respective permeability characteristics. The aquifer physical model constructed using these materials can more realistically simulate the non-uniform distribution characteristics of the coexistence of low-permeability background, medium-permeability transition, and high-permeability water-rich zones in natural aquifers, and can realize the dynamic evolution of dominant seepage channels in experiments, thereby significantly improving the realism of physical simulation experiments.

[0039] like Figure 2 As shown, the present invention also provides a method for simulating the heterogeneity of water-bearing capacity in loose rock aquifers, using the simulation material for the heterogeneity of water-bearing capacity in loose rock aquifers as described in the aforementioned technical solution, including: S210: Establish a horizontal aquifer model.

[0040] S220: Divide the water-bearing regions for the flat aquifer model according to the preset water-bearing distribution; among them, the types of water-bearing regions include weak water-bearing regions, medium water-bearing regions and strong water-bearing regions.

[0041] S230: Low-permeability background material, medium-permeability transition material, and high-permeability water-rich material from the simulation material of the heterogeneity of water-bearing capacity of loose rock aquifers are laid alternately in the model box of the flat aquifer model to form a heterogeneous material distribution.

[0042] S240: After the aquifer is laid, water is continuously injected from one side of the flat aquifer model and water is discharged from the other side. After the flat aquifer model is injected with water, the soluble particles in the high-permeability water-rich material dissolve, the porosity and connectivity of the high-permeability area are improved, and thus a dynamically enhanced water-rich area and dominant seepage channels are formed, realizing the dynamic change simulation of the non-uniform structure of the aquifer's water-richness.

[0043] Furthermore, low-permeability background materials, medium-permeability transitional materials, and high-permeability water-rich materials from the simulation materials for the heterogeneous water-bearing capacity of loose rock aquifers are interleaved within the model box of the flat aquifer model to form a heterogeneous material distribution, including: After the highly permeable water-rich material is mixed evenly, it is prepared into an irregular agglomerated water-rich agglomerated structure, and the particle size of a single water-rich agglomerated ... During the laying of low-permeability background material and medium-permeability transition material, high-permeability water-rich clusters are buried in a random spatial distribution pattern. The spacing between the water-rich clusters is 5 to 20 cm, and the total volume of the water-rich clusters accounts for 20% of the total volume of the flat aquifer model. During the burial process, adjacent water-rich clusters do not come into direct contact with each other to ensure that a discrete spatial non-uniform structure is formed inside the flat aquifer model. After the water-rich mass is buried, low-permeability background material and medium-permeability transition material are laid and lightly compacted to enclose the water-rich mass inside the low-permeability background material, thus forming a spatially heterogeneous aquifer structure in which strong water-rich areas, medium water-rich areas and weak water-rich areas coexist. After the model is laid, it is hammered to compact it and then dried for 48 hours.

[0044] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A material for simulating the heterogeneity of water-bearing capacity in loose rock aquifers, characterized in that, include: Low-permeability background materials, medium-permeability transition materials, and high-permeability water-rich materials; among them, The low-permeability background material comprises fine particulate material and cementing material, wherein the fine particulate material accounts for 60% to 90% of the total mass of the low-permeability background material, and the cementing material accounts for 10% to 40% of the total mass of the low-permeability background material. The medium-permeability transition material includes medium-sized particles and cementing materials, wherein the medium-sized particles account for 70% to 90% of the total mass of the medium-permeability transition material, and the cementing materials account for 10% to 30% of the total mass of the medium-permeability transition material. The highly permeable water-rich material includes coarse particles and soluble particles, wherein the coarse particles account for 60% to 90% of the total mass of the highly permeable water-rich material, and the soluble particles account for 10% to 40% of the total mass of the highly permeable water-rich material.

2. The simulation material for the heterogeneity of water-bearing capacity of loose rock aquifers according to claim 1, characterized in that, The fine-particle material in the low-permeability background material is one or both of fine sand and silt, and the cementing material in the low-permeability background material is one or both of gypsum and cement.

3. The simulation material for the heterogeneity of water-bearing capacity of loose rock aquifers according to claim 1, characterized in that, The low-permeability background material also includes a filler material; the filler material is one or both of bentonite and kaolin, and the amount of the filler material accounts for 10 to 15% of the total mass of the low-permeability background material composed of fine-particle materials and cementing materials.

4. The simulation material for the heterogeneity of water-bearing capacity of loose rock aquifers according to claim 1, characterized in that, The medium-permeability transition material contains medium-grained materials, namely medium sand and coarse sand.

5. The simulation material for the heterogeneity of water-bearing capacity of loose rock aquifers according to claim 1, characterized in that, The coarse particles in the highly permeable water-rich material are one or more of coarse sand, ceramsite, gravel, and coal gangue particles; the soluble particles in the highly permeable water-rich material are one or more of salt particles, sucrose particles, glucose particles, and starch particles.

6. The simulation material for the heterogeneity of water-bearing capacity of loose rock aquifers according to claim 1, characterized in that, The high-permeability water-rich material also includes a cementing material, the amount of which accounts for 15-20% of the total mass of the high-permeability water-rich material composed of coarse particles and soluble particles.

7. The simulation material for the heterogeneity of water-bearing capacity of loose rock aquifers according to claim 1, characterized in that, The low-permeability background material comprises, by mass percentage: 60% silt, 20% gypsum, 10% cement, and 10% bentonite, and is used to construct a weakly water-rich area. The components of the medium-permeability transition material, by mass percentage, include: 50% fine sand, 20% medium sand, 20% gypsum, and 10% cement, for constructing a medium-water-rich area; The components of the highly permeable water-rich material, by mass percentage, include: 40% coarse sand, 20% ceramsite, 10% salt, 10% sugar granules, 10% gypsum, and 10% cement. These are mixed with water to form irregularly shaped water-rich clusters with a particle size of 5–10 cm.

8. A method for simulating the heterogeneity of water-bearing capacity in loose rock aquifers, comprising using the simulation material for the heterogeneity of water-bearing capacity in loose rock aquifers as described in any one of claims 1-7, characterized in that, include: Establish a horizontal aquifer model; According to the preset water-bearing distribution, the horizontal aquifer model is divided into water-bearing regions; wherein, the types of water-bearing regions include weak water-bearing regions, moderate water-bearing regions, and strong water-bearing regions; The low-permeability background material, medium-permeability transition material, and high-permeability water-rich material in the simulation material of the heterogeneity of water-bearing capacity of loose rock aquifers are laid alternately in the model box of the flat aquifer model to form a heterogeneous material distribution. After the aquifer is laid, water is continuously injected from one side of the flat aquifer model and water exits from the other side. After the flat aquifer model is injected with water, the soluble particles in the high-permeability water-rich material dissolve, the porosity and connectivity of the high-permeability area are improved, and a dynamically enhanced water-rich area and dominant seepage channels are formed, thereby realizing the dynamic change simulation of the non-uniform structure of the aquifer's water-richness.

9. The method for simulating the heterogeneity of water-bearing capacity in loose rock aquifers according to claim 8, characterized in that, The low-permeability background material, medium-permeability transition material, and high-permeability water-rich material from the simulation material for the heterogeneous water-bearing capacity of loose rock aquifers are alternately laid in the model box of the flat aquifer model to form a heterogeneous material distribution, including: After the highly permeable water-rich material is mixed evenly, it is prepared into an irregular agglomerated water-rich agglomerated structure, and the particle size of a single water-rich agglomerated ... During the laying of low-permeability background material and medium-permeability transition material, high-permeability water-rich clusters are buried in a random spatial distribution pattern. The spacing between the water-rich clusters is 5 to 20 cm, and the total volume of the water-rich clusters accounts for 20% of the total volume of the flat aquifer model. During the burial process, adjacent water-rich clusters do not come into direct contact to ensure that a discrete spatial non-uniform structure is formed inside the flat aquifer model. After the water-rich mass is buried, low-permeability background material and medium-permeability transition material are laid and lightly compacted to enclose the water-rich mass inside the low-permeability background material, thus forming a spatially heterogeneous aquifer structure in which strong water-rich areas, medium water-rich areas and weak water-rich areas coexist. After the model is laid, it is hammered to compact it and then dried for 48 hours.

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