Seepage-preventing and water-retaining structure for ecological restoration of drought mining area in Yellow River basin and construction method of seepage-preventing and water-retaining structure

Abstract

The invention provides a seepage-preventing and water-retaining structure for ecological restoration of an arid mining area in the Yellow River basin and a construction method. The seepage-preventing and water-retaining structure comprises a seepage-preventing layer, a water-retaining layer and an evaporation-preventing layer. The seepage prevention layer is composed of Yellow River silt, bentonite, a base material aggregate agent and an organic material and is laid on the surface of the mine slope; the water retention layer is composed of Yellow River silt, coal gangue, an organic material, an organic fertilizer, a plant growth regulator and a base material composite water retention agent, and is laid on the surface of the permeation prevention layer; the anti-evaporation layer is composed of Yellow River silt, wood fibers, a base material adhesive, a base material composite water-retaining agent and plant seeds and is laid on the surface of the water-retaining layer. The seepage-preventing and water-retaining structure designed by the invention effectively combines three key functions: the seepage-preventing layer effectively prevents water from infiltrating too fast, the water-retaining layer has excellent water-storing and moisture-retaining capabilities, and the evaporation-preventing layer remarkably inhibits water evaporation.

Description

Technical Field

[0001] The invention relates to the field of slope ecological protection, and in particular to a seepage-blocking and water-retaining structure and a construction method for ecological restoration of arid mining areas in the Yellow River basin. Background Art

[0002] The upper reaches of the Yellow River are in an arid and semi-arid region. The region is rich in coal resources, but the large-scale development of coal mines has brought serious ecological problems, and the mining area ecology needs to be restored urgently. Mining area restoration requires a lot of soil, but soil resources are often scarce around arid mining areas. According to investigations, many arid mining areas in the Yellow River Basin are close to the Yellow River. If the Yellow River sediment is used for mining area ecological restoration, the problem of lack of soil in mining area ecological restoration can be solved.

[0003] However, the ecological environment in arid areas is poor, the area is short of water resources and has strong sunshine. During the process of ecological restoration of mines, it is often difficult to replenish sufficient water in the ecological restoration substrate, and the water in the substrate is easily evaporated and lost. On the other hand, the Yellow River sediment belongs to sandy soil, and the permeability coefficient of sandy soil is too large, so water is easily lost through seepage. Therefore, how to reduce the excessive permeability of the Yellow River sediment and design an ecological restoration structure suitable for arid mining areas is a problem that technicians in this field urgently need to solve. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a seepage-proof and water-retaining structure and a construction method for ecological restoration of arid mining areas in the Yellow River Basin, to provide a seepage-proof and water-retaining substrate for water-deficient mining areas in arid areas, and to solve the problem of too large permeability coefficient of Yellow River sediment and poor water retention capacity.

[0005] In order to achieve the above-mentioned technical features, the purpose of the present invention is achieved as follows: a seepage-proof and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin, including a mine slope, the slope surface of the mine slope is provided with a seepage-proof layer, the upper layer of the seepage-proof layer is paved with a steel mesh, the upper layer of the steel mesh is provided with a water-retaining layer, and the upper layer of the water-retaining layer is provided with an anti-evaporation layer; anchor rods are arranged through the interior of the water-retaining layer, the steel mesh and the seepage-proof layer, and the anchor rods extend to a certain depth inside the mine slope.

[0006] A construction method for a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin, comprising the following steps: Step 1, slope surface finishing: Remove loose soil, loose stones and weeds from the mine slope surface, fill in sunken and protruding parts to keep the slope flat, and take slope cutting measures if necessary to improve the smoothness of the slope surface; Step 2, gutter setting: Set up intercepting ditches above the slope, and set up transverse intercepting ditches and longitudinal drainage ditches on the slope according to local conditions to drain the surface water outside the slope; Step 3, preparing the barrier substrate A: Yellow River silt, bentonite, base material granulating agent and organic material are mixed to prepare seepage-blocking base material A, wherein the weight ratio of each material is 100:6-8:4-8:4-6; Step 4, prepare water-retaining substrate B: Yellow River silt, coal gangue, organic materials, organic fertilizers, plant growth regulators and composite water-retaining agents for substrates are mixed to prepare water-retaining substrate B, wherein the weight ratio of each material is: 100:2-4:4-6:1-3:10-14:0.06-0.1; Step 5, preparing the anti-evaporation substrate C: The Yellow River sediment, wood fiber, substrate adhesive, substrate composite water retaining agent and plant seeds are mixed to prepare an anti-evaporation substrate C, wherein the weight ratio of each material is: 100: 0.04-0.06: 2-3: 0.06-0.1: 0.006-0.008; Step 6: Lay the barrier layer: Put the seepage-blocking mixture A into a mixer, add water and mix evenly, and spray it evenly on the slope surface with a spraying machine, with a spraying thickness of 2-3cm; Step 7, maintenance of the barrier layer: Sprinkle water on the seepage-blocking layer for 2-3 days to make it reach the expected strength; Step 8, set up the reinforcement system: Lay the steel mesh on the surface of the seepage barrier layer, and then install the anchor rods. Drive the anchor rods into the slope to a depth of more than one meter to ensure that they are firmly fixed. Finally, use iron wire to fix the steel mesh to the anchor rods. Step 9: Lay the water-retaining layer: Put the water-retaining mixture B into a mixer, add water and mix evenly, and use a sprayer to spray evenly on the surface of the barrier layer, with a spraying thickness of 8-10cm; Step 10: Lay the anti-evaporation layer: Put the anti-evaporation mixture C into a mixer, add water and stir evenly, and use a sprayer to spray evenly on the surface of the water retention layer, with a spraying thickness of 3-4cm; Step 11, substrate maintenance: Cover the slope with straw mats and install irrigation devices to maintain the base material.

[0007] In step 3, the weight ratio of the Yellow River silt, bentonite, base material granulating agent and organic material is 100:7:6:5.

[0008] In step 4, the weight ratio of Yellow River silt, coal gangue, organic materials, organic fertilizers, plant growth regulators and base material composite water retaining agent is: 100:3:5:2:12:0.08.

[0009] In step 5, the weight ratio of Yellow River silt, wood fiber, substrate adhesive, substrate composite water-retaining agent and plant seeds is 100:0.05:2.5:0.08:0.007.

[0010] The Yellow River silt in step 3, step 4 and step 5 is the silt sediment in the Yellow River, which is stored on both sides of the Yellow River after dredging, and is naturally dried to have a water content of no more than 5%, and passes through a 5 mm aperture sieve; The organic material in step 3 and step 4 is a mixture of one or more of crushed wheat straw, crushed corn straw and sawdust.

[0011] The bentonite described in step 3 is a rock mineral with montmorillonite as the main component, which is processed from bentonite ore. The bentonite ore is first dried and then ground into powder using a grinding machine.

[0012] The substrate granule agent in step 3 is obtained by mixing polyacrylic acid, chitin, silicon fertilizer, and biological bacterial agent in a weight ratio of 2:1:0.5:0.5. The biological bacterial agent is selected from one or more of actinomycetes, Bacillus subtilis, rhizobia, and nitrogen-fixing photosynthetic bacteria.

[0013] The coal gangue described in step 4 is a rock with a dry ash content greater than 50% produced during the construction of coal mines, development and excavation, and coal mining. It is crushed by a crusher, and then Bacillus subtilis and Stenotrophomonas maltophilia are added. After stirring evenly, it is moved into a cement pool, covered with a black plastic sheet, kept warm at 30-32°C, stirred once every two days, and fermented for one week.

[0014] The organic fertilizer in step 4 is obtained by aerobic fermentation of a large amount of animal and plant residues, excrement and biological waste by adding ecologically beneficial spore bacteria, yeast, actinomycetes and Trichoderma among fungi; The plant growth regulator in step 4 is prepared by mixing potassium dihydrogen sulfate, glucose, sucrose, methyl cellulose, naphthylacetic acid, and water in a weight ratio of 4-6:8-10:10-15:40-60:5-10:1-2; The base material composite water-retaining agent in step 4 and step 5 is composed of sodium polyacrylate monomer and kaolin in a mass ratio of 1:1. The kaolin particles are 1-5 μm and embedded in the polymer resin, and the water absorption rate is more than 400 times.

[0015] The wood fiber in step 5 is pine fiber with a length of 10 mm; The substrate adhesive in step 5 is composed of xanthan gum, silicate cement and lignin in a mass ratio of 2:1:1. The lignin is obtained by grinding wood and extracting it with a 5% alkaline aqueous solution at 80° C. for 1-2 hours by stirring. Hydrochloric acid is added to the lignin alkaline solution to adjust the pH to 2.0, standing for stratification and filtering. The plant seeds described in step 5 should preferably be local drought-tolerant native species, 4 to 6 grass seeds, 1 to 3 shrub seeds, and a total of 6 to 8 grass and shrub seeds.

[0016] The present invention has the following beneficial effects: 1. The present invention proposes a seepage-blocking and water-retaining structure and a construction method for ecological restoration of arid mining areas in the Yellow River Basin. The seepage-blocking and water-retaining structure can effectively realize the water retention and storage functions by constructing a three-layer composite structure including a seepage-blocking layer, a water-retaining layer and an anti-evaporation layer, which is beneficial to the growth of plants in arid mining areas.

[0017] 2. In the present invention, bentonite, substrate agglomerating agent and organic material are added to the permeability barrier layer. Bentonite has a large permeability coefficient, the substrate agglomerating agent can promote the formation of agglomerates in the substrate, and the organic material can retain moisture, thereby inhibiting the infiltration of moisture in the structure.

[0018] 3. In the present invention, the water-retaining layer material is added with coal gangue, organic materials, plant growth regulators and base material composite water-retaining agent. The coal gangue can have a moisturizing effect, and the plant growth regulator can promote the growth of plant roots, thereby improving the water holding capacity of the base material.

[0019] 4. The composite water-retaining agent for the substrate in the present invention can absorb water, thus improving the water-retaining capacity of the structure; the anti-evaporation layer material is added with wood fiber, substrate adhesive and composite water-retaining agent for the substrate, the substrate adhesive can increase the integrity of the substrate surface, and the wood fiber can inhibit the formation of cracks on the substrate surface, thus reducing the evaporation rate of water on the surface of the structure. When rain falls on the surface of the structure, it penetrates from the anti-evaporation layer to the water-retaining layer, the water-retaining layer can absorb and store water to the greatest extent, the seepage-blocking layer can prevent the water in the water-retaining layer from seeping and losing, and the anti-evaporation layer can inhibit the evaporation and loss of water in the water-retaining layer. The present invention effectively improves the water-retaining capacity of the structure and can form a long-term and stable ecological restoration system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0021] Figure 1 Schematic diagram of the slope surface.

[0022] Figure 2 It is a flow chart for the construction of vegetation substrate.

[0023] In the figure: mine slope 1, seepage barrier layer 2, steel mesh 3, anchor rods 4, water retention layer 5, anti-evaporation layer 6. DETAILED DESCRIPTION

[0024] The embodiments of the present invention are further described below in conjunction with the accompanying drawings.

[0025] Embodiment 1: See also Figure 1, a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin, comprising a mine slope 1, a seepage-blocking layer 2 is arranged on the slope surface of the mine slope 1, a steel mesh 3 is laid on the upper layer of the seepage-blocking layer 2, a water-retaining layer 5 is laid on the upper layer of the steel mesh 3, and an anti-evaporation layer 6 is laid on the upper layer of the water-retaining layer 5; anchor rods 4 are arranged through the interior of the water-retaining layer 5, the steel mesh 3 and the seepage-blocking layer 2, and the anchor rods 4 extend to a certain depth inside the mine slope 1. By adopting the above-mentioned seepage-blocking and water-retaining structure, the seepage-blocking and water-retaining structure designed by the present invention effectively combines three key functions: the seepage-blocking layer effectively prevents water from infiltrating too quickly, the water-retaining layer has excellent water storage and moisture retention capabilities, and the anti-evaporation layer significantly inhibits water evaporation. The combination of the seepage-blocking layer, the water-retaining layer and the anti-evaporation layer ultimately exhibits good seepage-blocking and water-retaining performance, and can maintain long-term stable adaptation of ecological effects in the water-deficient and strong sunshine ecological environment of the arid mining area.

[0026] Among them, further, the seepage-blocking layer is composed of Yellow River silt, bentonite, base material granulating agent and organic material, and is laid on the surface of the mine slope with a laying thickness of 2-3cm; the water-retaining layer is composed of Yellow River silt, coal gangue, organic material, organic fertilizer, plant growth regulator and base material composite water-retaining agent, and is laid on the surface of the seepage-blocking layer with a laying thickness of 8-10cm; the anti-evaporation layer is composed of Yellow River silt, wood fiber, base material adhesive, base material composite water-retaining agent and plant seeds, and is laid on the surface of the water-retaining layer with a laying thickness of 3-4cm.

[0027] Embodiment 2: See also Figure 2 The present invention provides a construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin, comprising the following steps: Step 1: Slope surface finishing: remove loose materials such as loose soil, loose stones and weeds from the mine slope surface, fill in recessed and protruding parts to keep the slope flat, and take slope cutting measures if necessary to improve the smoothness of the slope surface.

[0028] Step 2, drainage ditch setting: Set up intercepting ditches above the slope, and set up horizontal intercepting ditches and longitudinal drainage ditches on the slope according to local conditions to effectively drain the surface water outside the slope.

[0029] Step 3, preparing the seepage-blocking substrate A: mixing Yellow River silt, bentonite, substrate granulating agent and organic material to prepare the seepage-blocking substrate A, wherein the weight ratio of each material is 100:6-8:4-8:4-6.

[0030] Step 4, preparing water-retaining substrate B: mixing Yellow River silt, coal gangue, organic materials, organic fertilizers, plant growth regulators and substrate composite water-retaining agent to prepare water-retaining substrate B, wherein the weight ratio of each material is: 100:2-4:4-6:1-3:10-14:0.06-0.1.

[0031] Step 5, preparing anti-evaporation substrate C: mixing Yellow River silt, wood fiber, substrate adhesive, substrate composite water-retaining agent and plant seeds to prepare anti-evaporation substrate C, wherein the weight ratio of each material is: 100: 0.04-0.06: 2-3: 0.06-0.1: 0.006-0.008.

[0032] Step 6, laying the seepage-proof layer: put the seepage-proof mixture A into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the slope surface with a spraying thickness of 2-3 cm.

[0033] Step 7, curing of the seepage-proof layer: sprinkle water on the seepage-proof layer for 2-3 days to allow the seepage-proof layer to reach the expected strength.

[0034] Step 8, set up the reinforcement system: lay a steel mesh on the surface of the barrier layer, then install anchor rods, drive the anchor rods into the slope to a depth of more than one meter to ensure that they are firmly fixed, and finally use wire to fix the steel mesh to the anchor rods.

[0035] Step 9, laying the water-retaining layer: put the water-retaining mixture B into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the surface of the seepage-proof layer. The spraying thickness is 8-10cm.

[0036] Step 10, laying the anti-evaporation layer: put the anti-evaporation mixture C into a mixer, add water and stir evenly, and use a sprayer to evenly spray it on the surface of the water-retaining layer. The spraying thickness is 3-4 cm.

[0037] Step 11, base material maintenance: Cover the slope with straw mats and install irrigation equipment to maintain the base material.

[0038] Preferably, in step 3, the weight ratio of Yellow River silt, bentonite, base material granulating agent and organic material is 100:7:6:5.

[0039] Preferably, in step 4, the weight ratio of Yellow River silt, coal gangue, organic material, organic fertilizer, plant growth regulator and base material composite water-retaining agent is: 100:3:5:2:12:0.08.

[0040] Preferably, in step 5, the weight ratio of Yellow River silt, wood fiber, substrate adhesive, substrate composite water-retaining agent and plant seeds is: 100:0.05:2.5:0.08:0.007.

[0041] Preferably, the Yellow River silt in step 3, step 4 and step 5 is silt sediment in the Yellow River, which is stored on both sides of the Yellow River after dredging, and is naturally dried to have a moisture content of no more than 5%, and passes through a 5 mm aperture sieve.

[0042] Preferably, the organic material in step 3 and step 4 is a mixture of one or more of crushed wheat straw, crushed corn straw and sawdust.

[0043] Preferably, the bentonite in step 3 is a rock mineral with montmorillonite as the main component, which is processed from bentonite ore. The bentonite ore is first dried and then ground into powder using a grinding machine.

[0044] Preferably, the substrate granulating agent in step 3 is obtained by mixing polyacrylic acid, chitin, silicon fertilizer, and biological bacterial agent in a weight ratio of 2:1:0.5:0.5, and the biological bacterial agent is selected from one or more of actinomycetes, Bacillus subtilis, rhizobia, and nitrogen-fixing photosynthetic bacteria.

[0045] Preferably, the coal gangue described in step 4 is a rock with a dry ash content greater than 50% produced during the construction of coal mines, development and excavation, and coal mining. It is crushed by a crusher, and then Bacillus subtilis and Stenotrophomonas maltophilia are added. After stirring evenly, it is moved into a cement pool, covered with a black plastic sheet, kept warm at 30-32°C, stirred once every two days, and fermented for one week.

[0046] Preferably, the organic fertilizer in step 4 is purchased from Nanjing Woyou Biofertilizer Co., Ltd., and is produced by aerobic fermentation of a large amount of animal and plant residues, excrement and biological waste by adding ecologically beneficial spore-forming bacteria, yeast, actinomycetes, Trichoderma and the like among fungi.

[0047] Preferably, the plant growth regulator in step 4 is prepared by mixing potassium dihydrogen sulfate, glucose, sucrose, methyl cellulose, naphthylacetic acid and water in a weight ratio of 4-6:8-10:10-15:40-60:5-10:1-2.

[0048] Preferably, the substrate composite water-retaining agent in step 4 and step 5 is composed of sodium polyacrylate monomer and kaolin in a mass ratio of 1:1, the kaolin particles are 1-5 μm, embedded in the polymer resin, and the water absorption rate can reach more than 400 times.

[0049] Preferably, the wood fiber in step 5 is pine fiber with a length of 10 mm.

[0050] Preferably, the substrate adhesive in step 5 is composed of xanthan gum, silicate cement and lignin in a mass ratio of 2:1:1. The lignin is obtained by crushing the wood and extracting it with a 5% alkaline aqueous solution at 80°C with stirring for 1-2h. Hydrochloric acid is added to the lignin alkaline solution to adjust the pH to 2.0, standing for stratification and filtering.

[0051] Preferably, the plant seeds in step 5 are preferably selected from local drought-tolerant native species, 4-6 grass seeds can be selected, 1-3 shrub seeds can be selected, and the total number of grass and shrub seeds is 6-8.

[0052] Embodiment 3: Huangbaici Mine Area Dumping Site in Wuhai City, Inner Mongolia, with a slope of 50 degrees: Slope surface finishing: remove loose materials such as loose soil, loose stones and weeds from the mine slope surface, fill in the depressions and protrusions to keep the slope flat, and take slope cutting measures when necessary to improve the smoothness of the slope surface.

[0053] Drainage ditch setting: Set up intercepting ditches above the slope, and set up horizontal intercepting ditches and longitudinal drainage ditches on the slope according to local conditions to effectively drain the surface water outside the slope.

[0054] Preparation of seepage-blocking substrate A: Yellow River silt, bentonite, substrate granulating agent and organic material are mixed to prepare seepage-blocking substrate A, wherein the weight ratio of each material is 100:6:4:4.

[0055] Preparation of water-retaining substrate B: Yellow River silt, coal gangue, organic materials, organic fertilizers, plant growth regulators and substrate composite water-retaining agents are mixed to prepare water-retaining substrate B, wherein the weight ratio of each material is: 100:2:4:1:10:0.06.

[0056] Preparation of anti-evaporation substrate C: Yellow River silt, wood fiber, substrate adhesive, substrate composite water-retaining agent and plant seeds are mixed to prepare anti-evaporation substrate C, wherein the weight ratio of each material is 100:0.04:2:0.06:0.006.

[0057] Laying the anti-seepage layer: put the anti-seepage mixture A into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the slope surface with a spraying thickness of 2-3cm.

[0058] Maintenance of the seepage-proof layer: Sprinkle water on the seepage-proof layer for 2-3 days to allow the seepage-proof layer to reach the expected strength.

[0059] Set up the reinforcement system: lay the steel mesh on the surface of the barrier layer, and then install the anchor rods. Drive the anchor rods into the slope to a depth of more than one meter to ensure that they are firmly fixed. Finally, use wire to fix the steel mesh to the anchor rods.

[0060] Laying the water-retaining layer: put the water-retaining mixture B into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the surface of the seepage-proof layer. The spraying thickness is 8-10cm.

[0061] Laying the anti-evaporation layer: put the anti-evaporation mixture C into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the surface of the water-retaining layer. The spraying thickness is 3-4cm.

[0062] Substrate maintenance: Cover the slope with straw mats and install irrigation devices to maintain the substrate.

[0063] Embodiment 4: Huangbaici Mine Area Dumping Site in Wuhai City, Inner Mongolia, with a slope of 45 degrees: Slope surface finishing: remove loose materials such as loose soil, loose stones and weeds from the mine slope surface, fill in the depressions and protrusions to keep the slope flat, and take slope cutting measures when necessary to improve the smoothness of the slope surface.

[0064] Drainage ditch setting: Set up intercepting ditches above the slope, and set up horizontal intercepting ditches and longitudinal drainage ditches on the slope according to local conditions to effectively drain the surface water outside the slope.

[0065] Preparation of seepage-blocking substrate A: Yellow River silt, bentonite, substrate granulating agent and organic material are mixed to prepare seepage-blocking substrate A, wherein the weight ratio of each material is 100:7:6:5.

[0066] Preparation of water-retaining substrate B: Yellow River silt, coal gangue, organic materials, organic fertilizers, plant growth regulators and substrate composite water-retaining agents are mixed to prepare water-retaining substrate B, wherein the weight ratio of each material is: 100:3:5:2:12:0.08.

[0067] Preparation of anti-evaporation substrate C: Yellow River silt, wood fiber, substrate adhesive, substrate composite water-retaining agent and plant seeds are mixed to prepare anti-evaporation substrate C, wherein the weight ratio of each material is: 100:0.05:2.5:0.08:0.007.

[0068] Laying the anti-seepage layer: put the anti-seepage mixture A into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the slope surface with a spraying thickness of 2-3cm.

[0069] Maintenance of the seepage-proof layer: Sprinkle water on the seepage-proof layer for 2-3 days to allow the seepage-proof layer to reach the expected strength.

[0070] Set up the reinforcement system: lay the steel mesh on the surface of the barrier layer, and then install the anchor rods. Drive the anchor rods into the slope to a depth of more than one meter to ensure that they are firmly fixed. Finally, use wire to fix the steel mesh to the anchor rods.

[0071] Laying the water-retaining layer: put the water-retaining mixture B into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the surface of the seepage-proof layer. The spraying thickness is 8-10cm.

[0072] Laying the anti-evaporation layer: put the anti-evaporation mixture C into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the surface of the water-retaining layer. The spraying thickness is 3-4cm.

[0073] Substrate maintenance: Cover the slope with straw mats and install irrigation devices to maintain the substrate.

[0074] Embodiment 5: The dumping ground of Suhaitu Mine Area in Wuhai City, Inner Mongolia, has a slope of 60 degrees: Slope surface finishing: remove loose materials such as loose soil, loose stones and weeds from the mine slope surface, fill in the depressions and protrusions to keep the slope flat, and take slope cutting measures when necessary to improve the smoothness of the slope surface.

[0075] Drainage ditch setting: Set up intercepting ditches above the slope, and set up horizontal intercepting ditches and longitudinal drainage ditches on the slope according to local conditions to effectively drain the surface water outside the slope.

[0076] Preparation of seepage-blocking substrate A: Yellow River silt, bentonite, substrate granulating agent and organic material are mixed to prepare seepage-blocking substrate A, wherein the weight ratio of each material is 100:8:8:6.

[0077] Preparation of water-retaining substrate B: Yellow River silt, coal gangue, organic materials, organic fertilizers, plant growth regulators and substrate composite water-retaining agents are mixed to prepare water-retaining substrate B, wherein the weight ratio of each material is: 100:4:6:3:14:0.1.

[0078] Preparation of anti-evaporation substrate C: Yellow River silt, wood fiber, substrate adhesive, substrate composite water-retaining agent and plant seeds are mixed to prepare anti-evaporation substrate C, wherein the weight ratio of each material is 100:0.06:3:0.1:0.008.

[0079] Laying the anti-seepage layer: put the anti-seepage mixture A into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the slope surface with a spraying thickness of 2-3cm.

[0080] Maintenance of the seepage-proof layer: Sprinkle water on the seepage-proof layer for 2-3 days to allow the seepage-proof layer to reach the expected strength.

[0081] Set up the reinforcement system: lay the steel mesh on the surface of the barrier layer, and then install the anchor rods. Drive the anchor rods into the slope to a depth of more than one meter to ensure that they are firmly fixed. Finally, use wire to fix the steel mesh to the anchor rods.

[0082] Laying the water-retaining layer: put the water-retaining mixture B into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the surface of the seepage-proof layer. The spraying thickness is 8-10cm.

[0083] Laying the anti-evaporation layer: put the anti-evaporation mixture C into a mixer, add water and mix evenly, and use a sprayer to evenly spray it on the surface of the water-retaining layer. The spraying thickness is 3-4cm.

[0084] Substrate maintenance: Cover the slope with straw mats and install irrigation devices to maintain the substrate.

[0085] The Yellow River sediment-based vegetation substrate obtained in the above embodiment was tested for its bulk density, total porosity, field water holding capacity, permeability coefficient, cohesion and internal friction angle after covering and curing for 7 days and 30 days. The results are as follows: Table 1 7d indicator monitoring results Example 3 Example 4 Example 5 <![CDATA[Bulk density (g / cm 3 ).]]> 1.42 1.38 1.35 Total porosity (%) 48.94 52.36 54.27 Water content (%) 14.15 11.56 12.96 Saturated water content (%) 38.15 36.42 37.21 Field water capacity (%) 19.86 20.43 18.46 Cumulative water loss at 40℃ for 7 days (%) 67.66 72.01 70.61 <![CDATA[Coefficient of permeability (10 -5 )]]> 6.1 6.5 5.9 Cohesion c (kPa) 30.08 29.98 29.35 Internal friction angle φ (°) 32.4 31.4 33.3 Table 2 30d indicator monitoring results Example 3 Example 4 Example 5 <![CDATA[Bulk density (g / cm 3 ).]]> 1.37 1.31 1.32 Total porosity (%) 52.67 53.76 55.48 Water content (%) 16.87 12.94 14.37 Saturated water content (%) 40.32 37.53 39.76 Field water capacity (%) 20.57 22.08 19.83 Cumulative water loss at 40℃ for 7 days (%) 62.30 66.21 65.43 <![CDATA[Coefficient of permeability (10 -5 )]]> 8.2 8.4 7.3 Cohesion c (kPa) 32.14 34.32 32.27 Internal friction angle φ (°) 34.2 35.8 34.7

Claims

1. A seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin, characterized in that: The invention comprises a mine slope (1), wherein the slope surface of the mine slope (1) is provided with a seepage barrier layer (2), a steel mesh (3) is laid on the upper layer of the seepage barrier layer (2), a water-retaining layer (5) is laid on the upper layer of the steel mesh (3), and an anti-evaporation layer (6) is laid on the upper layer of the water-retaining layer (5); anchor rods (4) are arranged through the water-retaining layer (5), the steel mesh (3) and the seepage barrier layer (2), and the anchor rods (4) extend into the mine slope (1) to a certain depth.

2. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin as claimed in claim 1, characterized in that: The following steps are involved: Step 1, slope surface finishing: Remove loose soil, loose stones and weeds from the mine slope surface, fill in sunken and protruding parts to keep the slope flat, and take slope cutting measures if necessary to improve the smoothness of the slope surface; Step 2, gutter setting: Set up intercepting ditches above the slope, and set up transverse intercepting ditches and longitudinal drainage ditches on the slope according to local conditions to drain the surface water outside the slope; Step 3, preparing the barrier substrate A: Yellow River silt, bentonite, base material granulating agent and organic material are mixed to prepare seepage-blocking base material A, wherein the weight ratio of each material is 100:6-8:4-8:4-6; Step 4, prepare water-retaining substrate B: Yellow River silt, coal gangue, organic materials, organic fertilizers, plant growth regulators and composite water-retaining agents for substrates are mixed to prepare water-retaining substrate B, wherein the weight ratio of each material is: 100:2-4:4-6:1-3:10-14:0.06-0.1; Step 5, preparing the anti-evaporation substrate C: The Yellow River sediment, wood fiber, substrate adhesive, substrate composite water retaining agent and plant seeds are mixed to prepare an anti-evaporation substrate C, wherein the weight ratio of each material is: 100: 0.04-0.06: 2-3: 0.06-0.1: 0.006-0.008; Step 6: Lay the barrier layer: Put the seepage-blocking mixture A into a mixer, add water and mix evenly, and spray it evenly on the slope surface with a spraying machine, with a spraying thickness of 2-3cm; Step 7, maintenance of the barrier layer: Sprinkle water on the seepage-blocking layer for 2-3 days to make it reach the expected strength; Step 8, set up the reinforcement system: Lay the steel mesh on the surface of the seepage barrier layer, and then install the anchor rods. Drive the anchor rods into the slope to a depth of more than one meter to ensure that they are firmly fixed. Finally, use iron wire to fix the steel mesh to the anchor rods. Step 9: Lay the water-retaining layer: Put the water-retaining mixture B into a mixer, add water and mix evenly, and use a sprayer to spray evenly on the surface of the barrier layer, with a spraying thickness of 8-10cm; Step 10: Lay the anti-evaporation layer: Put the anti-evaporation mixture C into a mixer, add water and stir evenly, and use a sprayer to spray evenly on the surface of the water retention layer, with a spraying thickness of 3-4cm; Step 11, substrate maintenance: Cover the slope with straw mats and install irrigation devices to maintain the base material.

3. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin according to claim 2 is characterized in that: In step 3, the weight ratio of the Yellow River silt, bentonite, base material granulating agent and organic material is 100:7:6:

5.

4. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin according to claim 2 is characterized in that: In step 4, the weight ratio of Yellow River silt, coal gangue, organic materials, organic fertilizers, plant growth regulators and base material composite water retaining agent is: 100:3:5:2:12:0.

08.

5. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin according to claim 2 is characterized in that: In step 5, the weight ratio of Yellow River silt, wood fiber, substrate adhesive, substrate composite water-retaining agent and plant seeds is 100:0.05:2.5:0.08:0.

007.

6. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin according to claim 2, characterized in that: The Yellow River silt in step 3, step 4 and step 5 is the silt sediment in the Yellow River, which is stored on both sides of the Yellow River after dredging, and is naturally dried to have a water content of no more than 5%, and passes through a 5 mm aperture sieve; The organic material in step 3 and step 4 is a mixture of one or more of crushed wheat straw, crushed corn straw and sawdust. The bentonite described in step 3 is a rock mineral with montmorillonite as the main component, which is processed from bentonite ore. The bentonite ore is first dried and then ground into powder using a grinding machine.

7. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin according to claim 2, characterized in that: The substrate granule agent in step 3 is obtained by mixing polyacrylic acid, chitin, silicon fertilizer, and biological bacterial agent in a weight ratio of 2:1:0.5:0.

5. The biological bacterial agent is selected from one or more of actinomycetes, Bacillus subtilis, rhizobia, and nitrogen-fixing photosynthetic bacteria.

8. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin according to claim 2, characterized in that: The coal gangue described in step 4 is a rock with a dry ash content greater than 50% produced during the construction of coal mines, development and excavation, and coal mining. It is crushed by a crusher, and then Bacillus subtilis and Stenotrophomonas maltophilia are added. After stirring evenly, it is moved into a cement pool, covered with a black plastic sheet, kept warm at 30-32°C, stirred once every two days, and fermented for one week.

9. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin according to claim 2, characterized in that: The organic fertilizer in step 4 is obtained by aerobic fermentation of a large amount of animal and plant residues, excrement and biological waste by adding ecologically beneficial spore bacteria, yeast, actinomycetes and Trichoderma among fungi; The plant growth regulator in step 4 is prepared by mixing potassium dihydrogen sulfate, glucose, sucrose, methyl cellulose, naphthylacetic acid, and water in a weight ratio of 4-6:8-10:10-15:40-60:5-10:1-2; The base material composite water-retaining agent in step 4 and step 5 is composed of sodium polyacrylate monomer and kaolin in a mass ratio of 1:

1. The kaolin particles are 1-5 μm and embedded in the polymer resin, and the water absorption rate is more than 400 times.

10. The construction method of a seepage-blocking and water-retaining structure for ecological restoration of arid mining areas in the Yellow River Basin according to claim 2, characterized in that: The wood fiber in step 5 is pine fiber with a length of 10 mm; The substrate adhesive in step 5 is composed of xanthan gum, silicate cement and lignin in a mass ratio of 2:1:

1. The lignin is obtained by grinding wood and extracting it with a 5% alkaline aqueous solution at 80° C. for 1-2 hours by stirring. Hydrochloric acid is added to the lignin alkaline solution to adjust the pH to 2.0, standing for stratification and filtering. The plant seeds described in step 5 should preferably be local drought-tolerant native species, 4 to 6 grass seeds, 1 to 3 shrub seeds, and a total of 6 to 8 grass and shrub seeds.

Images