CN114492226A - Evaluation method for aquifer mining permeation damage - Google Patents
Evaluation method for aquifer mining permeation damage Download PDFInfo
- Publication number
- CN114492226A CN114492226A CN202111635399.7A CN202111635399A CN114492226A CN 114492226 A CN114492226 A CN 114492226A CN 202111635399 A CN202111635399 A CN 202111635399A CN 114492226 A CN114492226 A CN 114492226A
- Authority
- CN
- China
- Prior art keywords
- mining
- aquifer
- fluid
- seepage
- setting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/28—Design optimisation, verification or simulation using fluid dynamics, e.g. using Navier-Stokes equations or computational fluid dynamics [CFD]
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2111/00—Details relating to CAD techniques
- G06F2111/10—Numerical modelling
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2113/00—Details relating to the application field
- G06F2113/08—Fluids
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
- G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Mathematical Physics (AREA)
- Fluid Mechanics (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Computing Systems (AREA)
- Pure & Applied Mathematics (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Geometry (AREA)
- General Engineering & Computer Science (AREA)
- Algebra (AREA)
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
Abstract
The invention relates to the technical field of osmotic damage evaluation, in particular to an evaluation method of aquifer mining osmotic damage, which comprises the steps of making certain assumption and simplification on original geological conditions; determining that the main body range of the model is positioned in the top plate overlying strata and comprises a part of the bottom plate strata; setting a seepage boundary: regarding the middle and above new boundary loose layers as impervious layers, regarding the lower content as a regional supply confined aquifer, setting the two sides of the model as permeable boundaries, and setting the top and bottom as impermeable boundaries; the numerical simulation mainly adopts a fluid and solid coupling method to research the motion law of the overburden and the fracture zone development height in the fully-mechanized caving mining. The method solves the problems of distribution of aquifer mining hydraulic gradient and modeling of osmotic damage rule in the existing simulation software; by determining a simulated main body and setting boundary conditions under certain assumed and simplified conditions, and further utilizing a fluid and solid coupling method, the movement law of the overburden rock and the development height of a fractured zone in fully-mechanized caving mining are researched through numerical simulation, and the precision of seepage field distribution and seepage damage simulation can be obviously improved.
Description
Technical Field
The invention relates to the technical field of osmotic damage evaluation, in particular to an evaluation method of aquifer mining osmotic damage.
Background
The research on the damage law of overlying strata is the key to reasonably reserving a waterproof coal rock pillar during water body underground coal mining, and is an essential important step for releasing the underground coal pressing reserve of the water body and ensuring the safe production of a mine. For decades, people adopt research methods of combining indoor tests and field actual measurements, combining theoretical analysis and model experiments, and mutually supplementing and verifying, so that the theory of coal seam mining overburden rock damage and engineering application make great progress. Particularly, in the last two decades, the rapid development of electronic computers makes the research on the damage of the coal seam mining overburden rock enter a new stage, and a numerical calculation method becomes one of important means for solving the problem of the damage of the coal seam mining overburden rock.
At present, a relevant model and an analysis method for determining the distribution rule of the aquifer mining hydraulic gradient based on numerical analysis and further judging the osmotic damage are lacked.
Disclosure of Invention
In order to solve the problem of the lack of the model and the analysis method, the invention establishes the aquifer mining fluid-solid coupling numerical calculation model, and obtains the hydraulic gradient distribution rule when water burst and sand break through numerical simulation.
The invention provides an evaluation method of aquifer mining penetration damage, which comprises the following steps:
making certain assumptions and simplifications on original geological conditions;
determining that the main body range of the model is positioned in the top plate overlying strata and comprises a part of the bottom plate strata;
setting a seepage boundary: regarding the middle and above new boundary loose layers as impervious layers, regarding the lower content as a regional supply confined aquifer, setting the two sides of the model as permeable boundaries, and setting the top and bottom as impermeable boundaries;
the numerical simulation mainly adopts a fluid and solid coupling method to research the motion law of the overburden and the fracture zone development height in the fully-mechanized caving mining.
Preferably, the numerical model is established under the following assumptions and simplifications:
(1) the rock mass is a porous continuous medium;
(2) through theoretical analysis and field actual measurement, the original ground stress field of the mining area adopts a self-weight stress field as the original ground stress field,
(3) the fluid conforms to Darcy's law in the pore medium and simultaneously satisfies the Biot equation; the fluid constitutive model employs an isotropic flow criterion of saturated steady flow.
Preferably, in the numerical simulation process, the simulation is firstly carried out to a stable state, the advancing direction is set to 20m each time in the coal mining layer, the calculation is circulated until the rock stratum is stable, the calculation result is stored, the circulation is continued in the next step of excavation, the calculation is sequentially carried out downwards until the advancing of the working face is finished, and the calculation process is finished.
Preferably, modeling and numerical simulation can be performed using the software FLAC 3D.
Preferably, in the calculation process, the fluid module in the FLAC3D is closed, the mining response of the model in the single mechanical field is calculated, then the fluid part is opened, the seepage field change under the current excavation step is calculated by using fluid-solid coupling, the seepage is calculated for 1-2 days, and then the next step of mining is carried out.
The invention has the following technical effects:
1. the method for evaluating the aquifer mining osmotic damage solves the problems of distribution of aquifer mining hydraulic gradient and modeling of osmotic damage rule in the conventional simulation software;
2. the method is characterized in that a simulated main body is determined and boundary conditions are set under certain assumed and simplified conditions, and then a fluid and solid coupling method is utilized, the motion law of the overburden stratum and the development height of a fracture zone in the fully-mechanized caving mining are researched through numerical simulation, so that the precision of seepage field distribution and seepage damage simulation can be obviously improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments will be briefly introduced below, it is obvious that the drawings in the following description are only some examples of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive labor.
FIG. 1 is a method for evaluating aquifer mining penetration damage;
FIG. 2 is a section of the seepage 48 hours trend and course in a simulation example;
FIG. 3 is a cross section of a bottom-containing section of a simulated example showing 48-hour percolation;
FIG. 4 is a perspective sectional view showing a distribution of seepage pressure in a simulation example.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.
Example 1:
as shown in fig. 1, a method for evaluating aquifer mining infiltration damage includes:
making certain assumptions and simplifications on original geological conditions;
determining that the main body range of the model is positioned in the top plate overlying strata and comprises a part of the bottom plate strata;
setting a seepage boundary: regarding the middle and above new boundary loose layers as impervious layers, regarding the lower content as a regional supply confined aquifer, setting the two sides of the model as permeable boundaries, and setting the top and bottom as impermeable boundaries;
the numerical simulation mainly adopts a fluid and solid coupling method to research the motion law of the overburden and the fracture zone development height in the fully-mechanized caving mining.
Example 2:
modeling and numerical simulation can be carried out by adopting software FLAC3D, a water-bearing stratum mining fluid-solid coupling numerical calculation model is established based on FLAC3D numerical software, and a hydraulic gradient distribution rule during water inrush and sand bursting is simulated. Under the condition of reflecting the original geological condition as much as possible, certain assumptions and simplifications are made on the original geological condition so as to be beneficial to mathematical calculation.
The numerical model is built under the following assumptions and simplifications:
(1) the rock mass is a porous continuous medium;
(2) through theoretical analysis and field actual measurement, the original ground stress field of the mining area adopts a self-weight stress field as the original ground stress field,
(3) the fluid conforms to Darcy's law in the pore medium and simultaneously satisfies the Biot equation; the fluid constitutive model employs an isotropic flow criterion of saturated steady flow.
Generally, the movement of the roof overburden is far greater than that of the bottom plate after mining, and the simulation focuses on the deformation and damage of the roof overburden during mining and the hydraulic change condition when four water contents are communicated, so that the main body range of the model is located in the roof overburden. In order to take into account the coordination of the deformation among the roof, the coal seam and the floor, the determination of the entire geometric model also includes a portion of the floor strata.
The seepage boundary is set as a good water-resisting layer because the thickness of the middle partition in the mining area is large and the distribution is stable. Due to the existence of the septum, the hydraulic connection between the aquifers above the septum and the aquifers below the aquifers loses, and the loose layers of the septum and the new boundaries can be regarded as impervious layers during modeling according to the hydrogeological conditions, so that the calculation result of the model is not influenced. The lower content has large thickness, different lithology and larger water-rich difference. And during modeling, the lower water content is taken as a region supply confined aquifer, the two sides of the model are set as permeable boundaries, and the top and the bottom are impermeable boundaries.
The numerical simulation is mainly used for researching the motion law of the overburden stratum and the development height of the fracture zone in the fully-mechanized caving mining. Firstly, the operation is simulated to a stable state, the advancing direction is set to be 20m each time in the mining coal bed, the calculation is circulated until the rock stratum is stable, the calculation result is stored, the circulation is continued in the next step of excavation and is sequentially carried out downwards until the advancing of the working face is finished, and the calculation process is finished. In the calculation process, a fluid module in the FLAC3D is closed, the mining response of the model in a single mechanical field is calculated, then a fluid part is opened, the seepage field change under the current excavation step is calculated by fluid-solid coupling, the seepage is calculated for 1-2 days, and then the next step of mining is carried out.
The simulation of the mining of the sand-prevention coal pillar reserved on a certain working face is actually explained, and the related results are shown in figures 2-4.
(1) When the working face is pushed to 100m, the fracture zone communicates with the four-component to form a seepage channel, the four-component water seeps to the goaf along the seepage channel, and the internal pore water pressure of the four-component water is lowest at a seepage outlet and is divergently distributed and increased to the periphery. In 1-6 hours after the four-contained water is communicated, the pressure of the pore water at the bottom of the four-contained water is sharply reduced, at the moment, the static reserve is consumed, and the water pressure gradually rises along with the supply of a lateral water source; during 6-24 hours after the four-contained communication, the pore water pressure distribution of the four-contained bottom gradually tends to be balanced; nearly reach seepage balance 24 hours after four contain of communication, pore water pressure no longer changes along with seepage time after 36 hours, completely reach stability, and the minimum of the stabilized four contain bottom pore water pressure is 1.94 MPa. When the pressure of the four-contained water is reduced to 2.2MPa, the pressure of the four-contained inner hole can be reduced to 1.02MPa at the lowest when the seepage is stable.
(2) Before the four-component dredging (the water pressure is 3.7 MPa), the top plate fractured zone is communicated with the four components, when the seepage is stable, the x-direction waterhead gradient dangerous areas at the bottom of the four components are mainly concentrated at the left side and the right side of the range of the water flowing fractured zone, and the influence range is 40-50 m; the y-direction waterhead gradient dangerous area is mainly concentrated on the front side and the rear side of the range of the water flowing fractured zone, and the influence range is 40-50 m; after the four-component drainage and drainage (the water pressure is 2.2 MPa), the hydraulic gradients in the x direction and the y direction are reduced to be below 1.01. In addition, simulation shows that the gradient value of the seepage damage dangerous water head in the middle of the four-component water tank is lower than that of the four-component water tank, and the distribution range is small. In addition, the penetration damage threat area of the weathering zone before dredging water pressure is mainly at the periphery of the plastic zone, the horizontal influence range is 3-6m, and the right penetration damage danger area is widely distributed, because the right side of the goaf is closer to the four-component, the penetration speed is higher. The penetration damage in the weathering zone area after the water pressure is dredged and reduced has little threat and is totally reduced to below the safe hydraulic gradient. The analysis shows that the hydrophobic depressurization can effectively prevent the osmotic damage in the tetrasodium and strong weathering zone and effectively judge the water inrush and sand bursting risks.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (5)
1. A method for evaluating aquifer mining penetration damage, comprising:
making certain assumptions and simplifications on original geological conditions;
determining that the main body range of the model is positioned in the top plate overlying strata and comprises a part of the bottom plate strata;
setting a seepage boundary: regarding the middle and above new boundary loose layers as impervious layers, regarding the lower content as a regional supply confined aquifer, setting the two sides of the model as permeable boundaries, and setting the top and bottom as impermeable boundaries;
the numerical simulation mainly adopts a fluid and solid coupling method to research the motion law of the overburden and the fracture zone development height in the fully-mechanized caving mining.
2. The method of claim 1, wherein the assuming and simplifying comprises:
(1) the rock mass is a porous continuous medium;
(2) through theoretical analysis and field actual measurement, the original ground stress field of the mining area adopts a self-weight stress field as the original ground stress field,
(3) the fluid conforms to Darcy's law in the pore medium and simultaneously satisfies the Biot equation; the fluid constitutive model employs an isotropic flow criterion of saturated steady flow.
3. The method for evaluating aquifer mining infiltration destruction according to claim 1, wherein in the numerical simulation process, the simulation is firstly operated to a stable state, the advancing direction is set to be 20m for each excavation in the mined coal seam, the calculation is circulated until the rock stratum is stable, the calculation result is stored, the circulation is continued in the next excavation step and is sequentially performed downwards until the advancing of the working face is finished, and the calculation process is finished.
4. The method for evaluating aquifer mining permeability damage according to claim 1, wherein the modeling and numerical simulation can be carried out by using software FLAC 3D.
5. The method for evaluating aquifer mining infiltration damage according to claim 1 or 4, wherein in the calculation process, a fluid module in the FLAC3D is closed, the mining response of the model in a single mechanical field is calculated, then a fluid part is opened, the seepage field change under the current excavation step is calculated by using fluid-solid coupling, the seepage is calculated for 1-2 days, and then the next step of mining is carried out.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111635399.7A CN114492226A (en) | 2021-12-29 | 2021-12-29 | Evaluation method for aquifer mining permeation damage |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111635399.7A CN114492226A (en) | 2021-12-29 | 2021-12-29 | Evaluation method for aquifer mining permeation damage |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114492226A true CN114492226A (en) | 2022-05-13 |
Family
ID=81509000
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111635399.7A Pending CN114492226A (en) | 2021-12-29 | 2021-12-29 | Evaluation method for aquifer mining permeation damage |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114492226A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115290528A (en) * | 2022-07-04 | 2022-11-04 | 中国矿业大学 | Characterization method for water-rich rock stratum fracture structure-seepage characteristic interaction |
| CN117151348A (en) * | 2023-10-31 | 2023-12-01 | 山东科技大学 | Method for distinguishing mining overburden high-level separation layer water burst type |
-
2021
- 2021-12-29 CN CN202111635399.7A patent/CN114492226A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115290528A (en) * | 2022-07-04 | 2022-11-04 | 中国矿业大学 | Characterization method for water-rich rock stratum fracture structure-seepage characteristic interaction |
| CN117151348A (en) * | 2023-10-31 | 2023-12-01 | 山东科技大学 | Method for distinguishing mining overburden high-level separation layer water burst type |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU2013252230B2 (en) | Method for distributed storage and use of underground water in mine | |
| CN101403314B (en) | Coal mine down-hole drilling hydraulic fracturing anti-reflection mash gas extraction technique | |
| CN110761814A (en) | Roof water control method based on presplitting and grouting modification | |
| CN103967507B (en) | A kind of curtain-grouting technique being suitable for rich water mine down-hole exploitation water blockoff | |
| CN114492226A (en) | Evaluation method for aquifer mining permeation damage | |
| CN100560937C (en) | A kind of thin basic rock shallow buried coal seam longwall face water retaining exploitation method | |
| CN105134129B (en) | Based on radially strength expansion gas pumping method for sealing | |
| CN106050234A (en) | Construction technique for protecting underground water in coal mining process | |
| CN109236297A (en) | Split the coal-mining method filled and leave coal seam in conjunction with the residual exploiting field of uplink second mining tool post | |
| CN105648988A (en) | Stage construction method for perpendicular anti-seepage structure of toe boards of concrete faced rockfill dam | |
| CN111379562B (en) | Water-controlled coal mining method and device under composite water body | |
| CN103758519A (en) | Thick and large mineral deposit stage subsequent filling method mining piecewise optimization design and implementation method | |
| Xuan et al. | Experimental study of slurry flow in mining-induced fractures during longwall overburden grout injection | |
| CN110567854A (en) | Water inflow prediction and calculation method based on hydrogeological model of adjacent mine after mine closing | |
| Morteza et al. | Leakage paths at the Lar Dam site, northern Iran | |
| CN110749533B (en) | Water-retention coal mining discrimination method based on equivalent water-resisting layer thickness | |
| CN111535863B (en) | Method for designing goaf gas storage cavern by combining curtain and water curtain | |
| CN103967506B (en) | A kind of ore body roof Karst Fissures is grown and the curtain-grouting method in strong Fu Shui mineral deposit | |
| CN208057104U (en) | The well pattern structure of deep layer bulk fractured reservoir is developed for gas drive | |
| CN115263304A (en) | Active intelligent regulation and control method for water level of mineral-bearing aquifer in coal-uranium coordinated mining area | |
| CN114444266A (en) | Feasibility evaluation method for improving recovery upper limit safety mining of coal seam under near unconsolidated formation | |
| CN115126506A (en) | Grouting transformation method for protecting coal pillar of fourth aquifer of liberation shallow part | |
| CN112664259A (en) | Trinity comprehensive outburst prevention method for high outburst coal seam | |
| Zhang et al. | Ground subsidence mechanism analysis of Longgui salt rock mining area: case study | |
| CN112943194B (en) | Method for preventing side underwater invasion in SAGD development process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |