CN114969910A - Waste rock filling reclamation method - Google Patents
Waste rock filling reclamation method Download PDFInfo
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- 238000011049 filling Methods 0.000 title claims abstract description 88
- 239000010878 waste rock Substances 0.000 title claims abstract description 70
- 238000000034 method Methods 0.000 title claims abstract description 37
- 239000004567 concrete Substances 0.000 claims abstract description 51
- 239000004570 mortar (masonry) Substances 0.000 claims abstract description 48
- 239000002689 soil Substances 0.000 claims abstract description 28
- 238000005096 rolling process Methods 0.000 claims abstract description 26
- 238000005507 spraying Methods 0.000 claims abstract description 10
- 239000002699 waste material Substances 0.000 claims abstract description 7
- 239000004568 cement Substances 0.000 claims abstract description 5
- 239000004576 sand Substances 0.000 claims abstract description 5
- 238000013461 design Methods 0.000 claims description 32
- 238000009412 basement excavation Methods 0.000 claims description 28
- 238000004364 calculation method Methods 0.000 claims description 18
- 238000007569 slipcasting Methods 0.000 claims description 11
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- 238000000926 separation method Methods 0.000 abstract 1
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
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- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
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- 229910001385 heavy metal Inorganic materials 0.000 description 3
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- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/13—Architectural design, e.g. computer-aided architectural design [CAAD] related to design of buildings, bridges, landscapes, production plants or roads
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- 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
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
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- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
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Abstract
The invention relates to a waste rock filling and reclamation method, which is characterized in that a waste rock-concrete mortar-loess composite structure is adopted to bury a ditch region, so that oxidation heating of waste rock and separation of harmful elements can be prevented, and negative effects brought by ditch landform are eliminated while the problem of land occupation of the waste rock is solved. The method comprises the following steps: determining the filling thickness proportion of a loess layer and a waste rock layer according to thermophysical parameters of the waste rock and the loess; determining a first thickness corresponding to a loess layer and a second thickness corresponding to a gangue layer according to the filling thickness proportion; filling waste rock with a first thickness in the bottommost layer of the gully area, and rolling and flattening to form a first waste rock layer 1; spraying concrete mortar on the surface of the first gangue layer 1 to form a first concrete mortar layer 2, wherein the concrete mortar comprises gangue, cement and medium sand; covering loess with a second thickness above the first concrete mortar layer 2 and rolling and flattening to form a first loess layer 3; covering surface soil above the first loess layer 3 and rolling and flattening to form a surface soil layer 4.
Description
Technical Field
The disclosure relates to the technical field of reclamation, in particular to a waste rock filling reclamation method.
Background
Gangue is a solid waste discharged in the coal mining and washing processing processes, and the accumulated stockpiling of coal gangue in China is more than 50 hundred million tons, and the coal gangue is continuously increased at the speed of 3.0-3.5 hundred million tons per year. The large amount of stockpiling of the coal gangue wastes land resources, and can generate conditions of spontaneous combustion, rain, argillization and the like, thereby causing serious harm to the environment, and the filling, reclamation and land preparation of the gangue and reclamation and forestation of the gangue become important tasks for the utilization of the coal gangue.
Disclosure of Invention
The invention aims to provide a waste rock filling and reclamation method, which aims to solve the problem of waste rock land occupation and eliminate negative effects brought by gully landform.
In order to achieve the above object, the present disclosure provides a waste rock filling reclamation method, including:
determining the filling thickness proportion of a loess layer and a waste rock layer according to thermophysical parameters of the waste rock and the loess;
determining a first thickness corresponding to the loess layer and a second thickness corresponding to the gangue layer according to the filling thickness proportion;
filling waste rock with the first thickness at the bottommost layer in the gully area, and rolling and flattening to form a first waste rock layer;
spraying concrete mortar on the surface of the first gangue layer to form a first concrete mortar layer, wherein the concrete mortar comprises gangue, cement and medium sand;
covering loess with the second thickness above the first concrete mortar layer, and rolling and flattening to form a first loess layer;
covering surface soil above the first loess layer, and rolling and flattening to form a surface soil layer.
Optionally, the method further comprises:
reserving a multipurpose hole during filling so as to carry out grouting through the multipurpose hole;
the multipurpose holes are arranged according to a preset interval, and the preset interval is determined according to the diffusion radius of the grouting liquid.
Optionally, the slip casting liquid diffusion radius is determined by the following calculation formula:
wherein, R represents slip casting liquid diffusion radius, and P represents the porosity of waste rock in the waste rock layer, and K represents the permeability coefficient of waste rock layer, and a represents and predetermines the slip casting section length, and delta P represents slip casting pressure, and R represents the radius of the intraformational multi-purpose hole of waste rock, and q represents the pump capacity of grouting pump, and t represents and reaches the used slip casting time of slip casting pressure.
Optionally, the covering and rolling of topsoil above the first loess layer to form a topsoil layer comprises:
covering waste rock with the first thickness above the first loess layer, and rolling and flattening to form a second waste rock layer;
spraying concrete mortar on the surface of the second gangue layer to form a second concrete mortar layer;
covering loess with the second thickness above the second concrete mortar layer, and rolling and flattening to form a second loess layer;
covering surface soil above the second loess layer and rolling and flattening to form the surface soil layer.
Optionally, according to the thermophysical parameters of the gangue and the loess, determining the filling thickness proportion of the loess layer and the gangue layer, includes:
according to the heat transfer process of waste rock under the different filling thickness proportion of waste rock and loess, confirm through numerical simulation software whether can to under the different filling thickness proportion the heat transfer is carried out to the center of waste rock layer, in order to confirm the filling thickness proportion.
Optionally, the determining a second thickness corresponding to the gangue layer according to the filling thickness ratio includes:
determining the initial thickness of the gangue layer according to the filling thickness proportion and the accumulation amount of the gangue;
determining a first porosity before the gangue is compacted and a second porosity after the gangue is compacted;
calculating the height difference before and after the gangue is compacted according to the first porosity and the second porosity;
and determining a second thickness corresponding to the gangue layer according to the initial thickness and the height difference.
Optionally, the determination is made by the following calculation:
wherein Δ h represents the height difference, p 1 Represents said first porosity, p 2 Representing the second porosity, h representing the initial thickness of the gangue layer.
Optionally, before the bottom layer in the gully area is filled with gangue with the first thickness and rolled and leveled, the method further comprises the following steps:
and spraying concrete mortar on the inner surface of the gully area.
Optionally, before the bottommost layer in the gully area is filled with gangue with the first thickness and rolled and leveled, the method further comprises the following steps:
and determining a target design elevation, a target total excavation amount and a target total filling amount according to the filling thickness proportion and the topographic characteristics of the gully area.
Optionally, the determining a target design elevation, a target total excavation amount and a target total filling amount according to the filling thickness proportion and the topographic characteristics of the gully area includes:
measuring ground elevation scattered point data of the gully area;
editing a topographic map of the gully area according to the ground elevation scattered point data, and extracting a characteristic line;
establishing a digital elevation model according to the topographic map and the characteristic line;
determining an initial design elevation under the condition of excavation and filling balance based on the digital elevation model;
adjusting the initial design elevation makes the ratio of total excavation volume and total fill volume equal to the loess layer thickness with the gangue layer the ratio of loess layer gross thickness to design elevation determination this moment is the target design elevation, total excavation volume determination this moment is the target total excavation volume, total fill volume determination this moment is the target total fill volume.
Through the technical scheme, the ditch flushing area is filled by adopting a three-layer composite structure of the waste rock, the concrete mortar and the loess, so that the waste rock can be prevented from being oxidized and heated and harmful elements can be prevented from being separated out, the negative influence caused by the ditch flushing terrain is eliminated while the land occupation problem of the waste rock is solved, and the land utilization value of the reclamation area is improved.
Additional features and advantages of the disclosure will be set forth in the detailed description which follows.
Drawings
The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:
FIG. 1 is a landfill schematic illustrating a spoil fill reclamation method according to an exemplary embodiment.
FIG. 2 is a flow diagram illustrating a method of waste fill reclamation according to an exemplary embodiment.
FIG. 3 is a flow diagram illustrating a digital elevation model mesh method calculation according to an exemplary embodiment.
FIG. 4 is a schematic diagram illustrating a multi-use aperture in accordance with an exemplary embodiment.
FIG. 5 is a schematic view of a multi-use aperture shown in accordance with another exemplary embodiment.
Fig. 6 is a graph of mean temperature monitoring data for a fill reclamation area, according to an example embodiment.
Description of the reference numerals
1-first gangue layer 2-first concrete mortar layer
3-first loess layer 4-topsoil layer
5-multipurpose hole 6-second gangue layer
7-second concrete mortar layer 8-second loess layer
Detailed Description
The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.
The gully is a groove formed by scouring the ground surface by discontinuous running water, is the largest scale in the erosion gully, and has the length of several kilometers or tens of kilometers, and the depth of several meters or tens of meters, sometimes more than one hundred meters. The gully is one of the largest erosion gullies, is the main landform characteristic of western regions in China, causes the potential safety hazard of natural disasters to be not neglected, and simultaneously, when the gully is mined under a sloping body, the mine pressure of an underground working face is obvious due to the terrain particularity of the gully area, thereby causing a series of adverse effects on underground production.
The inventor researches and discovers that although certain achievements are achieved by the existing waste filling reclamation technology, the following defects still exist: topographic factors such as gully and the like are not considered, local materials are not obtained according to local conditions, and a large amount of manpower and material resources are consumed; the problem that harmful elements are separated out when gangue meets water to pollute surrounding soil is not considered; the problem that the heating of the gangue is caused because the oxygen flow channel is not completely isolated is not considered.
In view of this, according to the characteristics that loess resources in a coal mine area at the northwest of Shanxi loess plateau are rich, vegetation is rare, and gully flushing development is realized, and the area combines the characteristics that mining intensity in the coal mine area is high, coal seams generally contain multiple layers of clamped gangue, and a large amount of gangue is accumulated due to mining activities.
Fig. 1 is a filling schematic diagram illustrating a waste fill reclamation according to an exemplary embodiment, and fig. 2 is a flow chart illustrating a waste fill reclamation method according to an exemplary embodiment. Referring to fig. 1 and 2, the waste rock filling reclamation method includes the following steps:
and S11, determining the filling thickness ratio of the loess layer and the waste rock layer according to the thermophysical parameters of the waste rock and the loess.
And S12, determining a first thickness corresponding to the loess layer and a second thickness corresponding to the gangue layer according to the filling thickness proportion.
And S13, filling gangue with the first thickness at the bottommost layer in the gully area, and rolling and flattening to form a first gangue layer 1.
And S14, spraying concrete mortar on the surface of the first gangue layer 1 to form a first concrete mortar layer 2, wherein the concrete mortar comprises gangue, cement and medium sand.
And S15, covering loess with a second thickness above the first concrete mortar layer 2 and rolling and flattening to form a first loess layer 3.
And S16, covering topsoil on the first loess layer 3 and rolling and flattening to form a topsoil layer 4.
It should be understood that the gangue filled in the lowest layer of the gully can be gangue meeting filling requirements after heavy metal element tests. Firstly, measuring the pH value of the gangue, then comparing and analyzing the agricultural land soil pollution risk screening value under the pH value, and determining whether the content of heavy metal elements is lower than the risk screening value according to the edible safety quality standard of crops so as to determine whether the safety quality standard is met.
Illustratively, if the PH value of the gangue is determined to be 7.56, the agricultural land soil pollution risk screening value under the PH value is analyzed in a comparative way, and according to the edible safety quality standard of crops, the contents of heavy metal elements are determined to be shown in table 1, and are all lower than the risk screening value and meet the safety quality standard, so that the gangue can be used for filling the bottommost layer in the gully area and rolling and flattening to form a first gangue layer 1.
TABLE 1
Because the chemical components in the gangue are contacted with oxygen to generate slow oxidation reaction, the oxidation process can generate heat and continuously accumulate the heat, and when the heat is accumulated to a certain temperature, coal and combustible substances in the gangue are combusted, so that the gangue is spontaneously combusted.
It should be understood that the concrete mortar layer is used for sealing the gangue layer, so that water stored in the loess layer cannot enter the gangue layer, the soil has the characteristic of not being filled with air after meeting water, and the loess layer can effectively isolate oxygen to avoid spontaneous combustion of the gangue due to heating. Therefore, harmful elements in the gangue layer are prevented from being separated out, and the gangue can be prevented from being oxidized and heated to influence the plant growth in the reclamation area. The average thickness of the concrete mortar layer may be 75 mm, and certainly, the thickness of the concrete mortar layer may also be adjusted according to actual conditions, which is not limited in the embodiment of the present disclosure.
It should also be understood that covering topsoil on the land after landfill can adjust soil quality, provide nutrients in soil necessary for plant growth, and provide good survival conditions for plant cultivation, the thickness of topsoil layer 4 may be 70 cm, and of course, the thickness of topsoil layer 4 may also be adjusted according to actual conditions, which is not limited by the embodiment of the present disclosure.
In addition, a loader can be adopted to lay the soil and the gangue layer by layer, a bulldozer is adopted to push the covering layer flat and compact, and the embodiment of the disclosure does not limit the laying and compacting process.
Through the technical scheme, the ditch flushing area is filled by adopting a three-layer composite structure of the waste rock, the concrete mortar and the loess, so that the waste rock can be prevented from being oxidized and heated and harmful elements can be prevented from being separated out, the negative influence caused by the ditch flushing terrain is eliminated while the land occupation problem of the waste rock is solved, and the land utilization value of the reclamation area is improved.
Because the gully area is originally a loose soil layer and is formed by intermittent flowing water washing, the stability of the soil on the inner surface of the gully area is poor, and therefore, according to a possible implementation mode of the gully area, before the bottommost layer of the gully area is filled with the gangue with the first thickness and is rolled and leveled, concrete mortar can be sprayed on the inner surface of the gully area.
Illustratively, the concrete mortar can be prepared by 780-790 parts of gangue, 510 parts of cement 490, 890 parts of medium sand 880 and 170 parts of water in parts by weight. The concrete mortar can also be prepared according to the weight part ratio and other materials, which are not limited in the embodiment of the disclosure. The used waste rock is low in weathering degree and high in hardness, meets the hardness standard for manufacturing gravel aggregate, can be firstly crushed into small pieces of waste rock by using a jaw crusher, then crushed into waste rock particles with the block diameter of 5-25 mm by using a counterattack crusher, and then prepared into concrete mortar by using the waste rock particles. The embodiment of the disclosure does not limit the method for crushing the gangue and the block diameter of the gangue particles. When the concrete mortar is sprayed, a GYP-90 hydraulic shotcrete machine can be adopted to spray the concrete mortar on the bank and the bottom of the ditch of the to-be-reclaimed gully area, the thickness is 50 mm-100 mm, and the concrete mortar is maintained after 8 hours of shotcrete construction, wherein the maintenance time is 7 days. The method for spraying the concrete mortar, the thickness of the concrete mortar layer and the method for maintaining the concrete mortar layer are not limited in the embodiment of the disclosure, and can be adaptively adjusted according to actual conditions in application.
Through the mode, the concrete mortar sprayed on the inner surface of the gully area can reinforce the inside of the gully, reduce the lateral deformation of rock mass, further increase the bearing capacity of the gully area soil after reclamation, and simultaneously prevent the leaching effect of water in the gully soil layer on the gangue from causing environmental pollution.
In a possible mode, before filling gangue with the first thickness at the bottommost layer in the gully area and rolling and leveling, the target design elevation, the target total excavation amount and the target total filling amount can be determined according to the filling thickness proportion and the topographic characteristics of the gully area.
It should be understood that the calculation of the target design elevation, the target total excavation amount and the target total filling amount is an important step of the engineering construction, and the engineering design stage must carry out budget calculation on the design elevation, the target total excavation amount and the target total filling amount, which is directly related to the cost approximate calculation and scheme optimization of the engineering. The embodiment of the present disclosure does not limit the manner of calculating the target design elevation, the target total excavation amount, and the target total filling amount.
In a possible mode, according to the filling thickness proportion and the topographic characteristics of a gully area, determining a target design elevation, a target total excavation amount and a target total filling amount, wherein the method comprises the steps of firstly measuring ground elevation scatter data of the gully area, then editing a topographic map of the gully area according to the ground elevation scatter data, extracting a characteristic line, then establishing a digital elevation model according to the topographic map and the characteristic line, then determining an initial design elevation under the condition of filling balance based on the digital elevation model, finally adjusting the initial design elevation to enable the ratio of the total excavation amount to the total filling amount to be equal to the ratio of the thickness of loess layer to the total thickness of gangue layer and loess layer, determining the design elevation at the moment as the target design, determining the total excavation amount at the moment as the target total excavation amount, and determining the total filling amount at the moment as the target total filling amount.
Exemplarily, the flow of calculating the target design elevation and the target total excavation and filling amount through the digital elevation model is as shown in fig. 3, referring to fig. 3, firstly editing a topographic map of a gully area according to measured ground elevation scatter data, extracting characteristic lines, then establishing the digital elevation model according to the topographic map and the characteristic lines, then determining an initial design elevation under the excavation and filling balance condition based on the digital elevation model, then adjusting the initial design elevation, calculating the total excavation amount and the total filling amount according to the adjusted design elevation, judging whether the ratio of the total excavation amount and the total filling amount is equal to the ratio of the loess layer thickness to the total thickness of the gangue layer and the loess layer, and when the ratio of the total excavation amount and the total filling amount is equal to the ratio of the loess layer thickness to the total thickness of the gangue layer and the loess layer, determining the design elevation and the total excavation and filling amount at the moment as the target design elevation and the target total excavation and filling amount, And (5) filling amount.
For example, the ground elevation scatter data for the gully area may include topographical point spacing, maximum east-west distance, maximum north-south distance, minimum elevation, maximum elevation, and the like. Then, earth calculation software such as EPS and CASS can be used for extracting various topographic and geomorphic elements influencing the calculation accuracy, editing and generating a simple topographic map, and extracting characteristic lines such as a slope top line, a slope bottom line, a ridge top line, a ridge bottom line and a boundary line of a terrain with uniform or flat elevation changes. And importing the simple topographic map and the characteristic lines into earthwork calculation software to generate a regular grid Digital Elevation Model (DEM), wherein the grid size can be set to be 1 m. It is worth explaining that any edge in the constructed DEM cannot be intersected with the characteristic line.
For example, the initial design elevation for the cut-fill balance case may be calculated by the following calculation:
H d ＝(∑H co +2∑H ed +3∑H tu +4∑H ce )
wherein H d Representing the initial design elevation under the condition of excavation and filling balance, n representing the total number of grid points, H co Elevation value H representing angular point ed Height, H, representing edge points tu Elevation value, H, representing an inflection point ce The elevation of the midpoint is shown.
For example, the elevation difference between each grid point and the initial design elevation may be calculated by the following calculation:
dH(i,j)＝H(i,j)-H d
h (i, j) represents the height value of the grid point with the abscissa of i and the ordinate of j, and dH (i, j) represents the height difference between the grid point with the abscissa of i and the ordinate of j and the initial design height.
For example, the earth volume of each grid point may be calculated by the following calculation:
wherein l represents the spacing of the grid points, V co (i, j) represents the earth volume of the corner point with abscissa i and ordinate j, V ed (i, j) represents the amount of earth at the edge point with the abscissa i and the ordinate j, V tu (i, j) represents the amount of earth at the inflection point with i on the abscissa and j on the ordinate, V ce (i, j) represents the amount of earth at the midpoint of the abscissa i and the ordinate j.
For example, the total excavation amount and the total filling amount in the case of the excavation and filling balance can be calculated by the following calculation formula:
wherein V (i, j) represents the earth volume of the grid point with the abscissa of i and the ordinate of j, V Digging machine Indicating the total excavation volume, V, in the case of fill balance Filling-in Indicating the total fill in the case of fill balance.
In a possible mode, the filling thickness proportion of the loess layer and the waste rock layer is determined according to thermophysical parameters of the waste rock and the loess, the heat transfer process of the waste rock can be performed according to different filling thickness proportions of the waste rock and the loess, and whether heat transfer can be performed to the center of the waste rock layer or not is determined through numerical simulation software according to different filling thickness proportions so as to determine the filling thickness proportion.
It should be understood that because the gangue has good heat storage conditions, when the heat in the gangue layer cannot be released to the outside in time, the temperature accumulation can cause the continuous rise in the gangue layer, and the temperature fed back to the ground surface is correspondingly higher, which is not beneficial to the survival and growth of plants. Therefore, the embodiment of the disclosure provides a thermal property parameter based on the difference of the waste rock and the loess, and determines whether the temperature in the waste rock layer can continuously rise or not and whether the high-temperature area can diffuse to the central area or not according to the heat transfer process of the loess and the waste rock under different thickness ratios, thereby determining the filling thickness ratio of the loess layer and the waste rock layer. Wherein, the thermal physical property parameters of the loess and the gangue are shown in the table 2.
TABLE 2
Illustratively, Abaqus numerical simulation software can be adopted to establish a quadrangular frustum pyramid model, a heat source is added on the outer surface of the model, loess and waste rock with different thickness proportions are used as materials in the quadrangular frustum pyramid model, the heat transfer problem of the waste rock is only considered on the premise of ensuring the simulation accuracy and precision, the quadrangular frustum pyramid model is divided into 11000 heat transfer units, then the initial temperature fields of the loess, the waste rock and the external environment are set to be 25 ℃, 372 ℃ spontaneous combustion temperature fields are respectively applied to two sides of the model, and the temperature simulation result when the temperature transfer in the model reaches a steady state is obtained by combining thermophysical parameters of the loess and the waste rock shown in table 1 under different filling thickness proportions of the waste rock and the loess.
For example, the different thickness ratios of the loess to the gangue can be set to be 1:4, 1:6, 1:8, 1:10 and 1: 12. Under the condition that the ratio of the loess to the gangue is 1:8, 1:10 and 1:12, the high-temperature area in the model diffuses to the central area, the internal temperature is generally higher, and under the condition that the ratio of the loess to the gangue is 1:4 and 1:6, the high-temperature area in the model does not diffuse to the central area and is in differential distribution. That is, when it is determined that the thickness ratio of the loess to the gangue is 1:6 or more, the high-temperature region inside the model does not diffuse toward the central region. Therefore, the thickness ratio of the loess to the gangue can be determined to be 1:6, and certainly, the thickness ratio of the loess to the gangue can be determined to be 1:5 or 1:4, and the adjustment can be specifically carried out according to the actual accumulation amount and the economic effect of the gangue, which is not limited by the embodiment of the disclosure.
In a possible mode, determining second thickness corresponding to the gangue layer according to the filling thickness proportion, determining initial thickness of the gangue layer according to the filling thickness proportion and the stacking amount of the gangue, then determining first porosity before gangue compaction and second porosity after gangue compaction, then calculating height difference before and after gangue compaction according to the first porosity and the second porosity, and finally determining second thickness corresponding to the gangue layer according to the initial thickness and the height difference.
It will be appreciated that because of the volume of void space between the spoil layers, there will be a difference in height in the layer of spoil after filling and roller compaction with spoil. The height difference before and after the gangue is compacted can be calculated according to the porosity before and after the gangue is compacted, and then the second thickness corresponding to the gangue layer is determined according to the initial height and the height difference.
For example, the corresponding second thickness of the gangue layer may be calculated by the following calculation:
h 2 ＝h+Δh
wherein h is 2 And h represents the corresponding second thickness of the gangue layer, h represents the initial thickness of the gangue layer, and deltah represents the height difference before and after the gangue is compacted.
In one possible form, the height difference before and after the gangue compaction is determined by the following calculation formula:
wherein Δ h represents a height difference, p 1 Denotes a first porosity, p 2 Representing the second porosity and h representing the initial thickness of the gangue layer.
For example, if the thickness of loess and gangue is determinedThe ratio is 1:6, and the thicknesses of the loess layer and the gangue layer are respectively determined to be 50 cm and 300 cm according to the actual accumulation amount and the economic effect of the gangue, namely the initial thickness h of the gangue layer is 300 cm. Then, calculating by the above calculation formula to obtain that delta h is 0.3658h, and the corresponding second thickness of the gangue layer is as follows: h is 2 H + Δ h is 300+0.3658 × 300 is 409.74 cm. Of course, the first thickness corresponding to the loess layer can be determined according to the height difference before and after the loess is compacted and the initial thickness of the loess layer determined according to the thickness ratio of the loess to the waste rock, and the embodiment of the disclosure does not limit the first thickness.
In a possible manner, the multipurpose holes 5 may be prepared during filling so as to perform grouting through the multipurpose holes 5, and the multipurpose holes 5 may be arranged at a predetermined interval, which may be determined according to a diffusion radius of the grouting liquid.
It should be understood that since the inside of the gully area is reclaimed by gangue, loess and concrete mortar filling, the structure of the internal soil is complicated compared to the non-reclaimed area, and the stability of the reclaimed area filled with gangue is low compared to the non-reclaimed area due to the structure of gangue and its chemical properties. Thus, a multipurpose hole can be reserved in filling. As shown in fig. 4, a temperature sensor may be disposed in the multipurpose hole 5 in the gangue layer, when the internal temperature of the gully is monitored to be abnormal, the multipurpose hole 5 may be used as a grouting hole, and the gangue layer is subjected to temperature-controlled grouting through the multipurpose hole 5 to adjust the internal temperature of the gangue layer. Also can consolidate the slip casting through this multiple-purpose hole 5 to the waste rock layer, improve the bearing capacity on waste rock layer, can also carry out water shutoff to the concrete mortar layer and consolidate the slip casting, further prevent the flow direction waste rock layer such as water in the gully soil horizon, this disclosed embodiment does not do all the injectures to the concrete usage of multiple-purpose hole 5 and the slip casting material that uses during the slip casting.
In a possible way, the slip-slurry diffusion radius is determined by the following calculation:
wherein R represents the diffusion radius of grouting liquid, P represents the porosity of gangue in the gangue layer, K represents the permeability coefficient of the gangue layer, a represents the length of the preset grouting section, delta P represents the grouting pressure, R represents the radius of the multipurpose hole 5 in the gangue layer, q represents the pump capacity of a grouting pump, and t represents the grouting time for achieving the grouting pressure.
Illustratively, fig. 3 is a schematic view of a multiple-use aperture 5 configuration shown in accordance with another exemplary embodiment. As shown in fig. 3, the preset grouting section length a may be determined according to the second thickness corresponding to the gangue layer. If the second thickness corresponding to the waste rock layer is 300 cm, the length a of the preset grouting section can be determined to be 300 cm, and the multipurpose hole 5 in the waste rock layer is arranged in the middle of the waste rock layer, so that the grouting liquid can be more fully diffused into the waste rock layer. If the thickness of the gangue layer is large, as shown in fig. 5, a plurality of multipurpose holes 5 may be provided in the gangue layer, which is not limited in the embodiment of the present disclosure. If the slurry diffusion radius r is 318 cm calculated through the calculation formula, it may be determined that the preset distance between the multipurpose holes 5 is 600 cm (the preset distance may be less than or equal to 2r), and the preset distance between the multipurpose holes 5 may also be set to 500 cm, so that grouting may also be more quickly diffused into a gangue layer, which is not limited in the embodiment of the present disclosure.
In a possible mode, covering surface soil above the first loess layer 3 and rolling and flattening to form a surface soil layer 4, covering gangue with a first thickness above the first loess layer 3 and rolling and flattening to form a second gangue layer 6, spraying concrete mortar on the surface of the second gangue layer 6 to form a second concrete mortar layer 7, covering loess with a second thickness above the second concrete mortar layer 7 and rolling and flattening to form a second loess layer 8, and covering surface soil above the second loess layer 8 and rolling and flattening to form the surface soil layer 4.
It should be understood that, as shown in fig. 4, the gangue layer, the concrete mortar layer and the loess layer may be defined as a composite layer, then the trench area is filled with a plurality of composite layers according to the depth and topographic features of the trench, and finally the top loess layer is covered with surface soil and rolled to form the surface soil layer 4. The number of layers of the composite layer is not limited in the embodiment of the disclosure, and can be adjusted according to the topographic characteristics of the specifically filled gully.
Through the technical scheme, the ditch flushing area is alternatively buried by adopting a three-layer composite structure of gangue-concrete mortar-loess, so that the gangue can be prevented from being oxidized and heated and harmful elements can be prevented from being separated out, the negative influence caused by the ditch flushing terrain is eliminated while the land occupation problem of the gangue is solved, and the land utilization value of the reclamation area is improved. And meanwhile, a multipurpose hole is reserved during filling, and temperature control grouting is carried out on the gangue layer through the multipurpose hole so as to adjust the internal temperature of the gangue layer in real time, thereby being beneficial to survival of the plants in the reclamation area.
Figure 6 is a graph of average temperature monitoring data for a fill reclamation area shown according to an exemplary embodiment. The maximum monitoring temperature of the gangue layer is 22.4 ℃, the minimum monitoring temperature is 20.5 ℃, the maximum monitoring temperature of the surface soil layer is 20.7 ℃, and the minimum monitoring temperature is 20.0 ℃. Therefore, the gangue filling and reclamation method can effectively inhibit low-temperature oxidation of the gangue and provide proper temperature for the growth of vegetation.
The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.
It should be noted that, in the above embodiments, the various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various possible combinations will not be further described in the present disclosure.
In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.
Claims (10)
1. A waste filling reclamation method is characterized by comprising the following steps:
determining the filling thickness proportion of a loess layer and a waste rock layer according to thermophysical parameters of the waste rock and the loess;
determining a first thickness corresponding to the loess layer and a second thickness corresponding to the gangue layer according to the filling thickness proportion;
filling waste rock with the first thickness at the bottommost layer in the gully area, and rolling and flattening to form a first waste rock layer;
spraying concrete mortar on the surface of the first gangue layer to form a first concrete mortar layer, wherein the concrete mortar comprises gangue, cement and medium sand;
covering loess with the second thickness above the first concrete mortar layer, and rolling and flattening to form a first loess layer;
covering surface soil above the first loess layer, and rolling and flattening to form a surface soil layer.
2. The method of claim 1, further comprising:
reserving a multipurpose hole during filling so as to carry out grouting through the multipurpose hole;
the multipurpose holes are arranged according to a preset interval, and the preset interval is determined according to the diffusion radius of the grouting liquid.
3. The method of claim 2, wherein the slip casting dispersion radius is determined by the following calculation:
wherein R represents the diffusion radius of the grouting liquid, P represents the porosity of gangue in the gangue layer, K represents the permeability coefficient of the gangue layer, a represents the length of a preset grouting section, delta P represents the grouting pressure, R represents the radius of a multipurpose hole in the gangue layer, q represents the pump capacity of the grouting pump, and t represents the grouting time for achieving the grouting pressure.
4. The method of claim 1, wherein said covering topsoil over said first loess layer and rolling it flat to form a topsoil layer comprises:
covering waste rock with the first thickness above the first loess layer, and rolling and flattening to form a second waste rock layer;
spraying concrete mortar on the surface of the second gangue layer to form a second concrete mortar layer;
covering loess with the second thickness above the second concrete mortar layer, and rolling and flattening to form a second loess layer;
covering surface soil above the second loess layer and rolling and flattening to form the surface soil layer.
5. The method of claim 1, wherein the determining the filling thickness ratio of the loess layer to the loess layer according to the thermophysical parameters of the gangue and the loess comprises:
according to the heat transfer process of waste rock under the different filling thickness proportion of waste rock and loess, confirm through numerical simulation software whether can to under the different filling thickness proportion the heat transfer is carried out to the center of waste rock layer, in order to confirm the filling thickness proportion.
6. The method according to claim 1, wherein the determining a second thickness corresponding to the gangue layer according to the filling thickness proportion comprises:
determining the initial thickness of the gangue layer according to the filling thickness proportion and the accumulation amount of the gangue;
determining a first porosity before the gangue is compacted and a second porosity after the gangue is compacted;
calculating the height difference before and after the gangue is compacted according to the first porosity and the second porosity;
and determining a second thickness corresponding to the gangue layer according to the initial thickness and the height difference.
7. The method of claim 6, wherein the determination is made by the following calculation:
wherein Δ h represents the height difference, p 1 Represents said first porosity, p 2 Representing the second porosity, h representing the initial thickness of the gangue layer.
8. The method of claim 1, further comprising, before the filling and crushing the bottom most layer of the gully area with spoil of the first thickness,:
and spraying concrete mortar on the inner surface of the gully area.
9. The method of claim 1, further comprising, prior to the bottommost layer in the gully area being filled with mine spoil of the first thickness and rolled flat:
and determining a target design elevation, a target total excavation amount and a target total filling amount according to the filling thickness proportion and the topographic characteristics of the gully area.
10. The method of claim 9, wherein determining a target design elevation and a target total excavation and fill based on the fill thickness fraction and the topographical features of the gully area comprises:
measuring ground elevation scattered point data of the gully area;
editing a topographic map of the gully area according to the ground elevation scattered point data, and extracting a characteristic line;
establishing a digital elevation model according to the topographic map and the characteristic line;
determining an initial design elevation under the condition of excavation and filling balance based on the digital elevation model;
adjusting the initial design elevation makes the ratio of total volume of digging and total volume of filling equal the loess layer thickness with the cash layer the ratio of loess layer gross thickness to design elevation determination this moment does target design elevation determines the total volume of digging this moment does the total volume of target, the total volume of filling this moment is determined to be the total volume of filling of target.
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Inventor after: Zhang Yunfeng Inventor after: Hao Xiangying Inventor after: Shi Huajun Inventor after: Wang Xufeng Inventor after: Gao Junqian Inventor after: Han Jincheng Inventor after: Bai Haijun Inventor after: Wu Jinxiong Inventor before: Zhang Yunfeng Inventor before: Hao Xiangying Inventor before: Shi Huajun Inventor before: Wang Xufeng Inventor before: Gao Junqian Inventor before: Han Jincheng Inventor before: Bai Haijun Inventor before: Wu Jinxiong |