A self-repairable mine road material and its preparation method and application

Abstract

The present invention discloses a self-repairable mine road material and its preparation method and application. The self-repairable mine road material includes a main material, a solid modifier and a binder; the main material includes blast pile slag and neutralized slag; the solid modifier is composed of industrial active magnesium oxide and copper smelting slag powder in a mass ratio of 1:4 to 1:3, and the amount of the solid modifier is 5 to 10% of the total mass of the main material; the effective components of the binder are polyvinyl alcohol and polyacrylamide, and the amount of polyvinyl alcohol is 0.2 to 0.5% relative to the total mass of the main material, and the amount of polyacrylamide is 0.02 to 0.05%. The self-repairable mine road material has high bending strength, good integrity, the characteristics of a flexible pavement, high early strength, and certain self-repairing performance. After absorbing water, small cracks can be closed by rolling, reducing dust, and showing extremely strong anti-cracking and durability.

Description

Technical Field

[0001] The invention belongs to the field of rapid construction and maintenance of open-pit mine roads, and in particular relates to a self-repairing mine road material and a preparation method and application thereof. Background Art

[0002] Compared with ordinary roads, open-pit mine transportation roads have the characteristics of extremely large load capacity and low traffic frequency. At the same time, due to the production characteristics of the mining industry, their geographical location is relatively remote, the natural conditions are relatively harsh, and the road construction time is relatively short. At present, there is no unified standard for open-pit mine road construction. Domestic mining companies often use nearby materials and use soil and stone around the mining site to build simple roads. However, after repeated heavy loading, it is easy to cause the following problems: (1) The bonding strength of simple soil and stone roads is lower than 0.5MPa, which is easy to cause road damage and cracking after repeated heavy loading; (2) Simple soil and stone roads or cracked concrete roads have large unevenness, which is very easy to cause tire wear and vehicle speed reduction, resulting in increased production costs; (3) After the road surface is damaged, mud and dust problems occur. Some mines have tried to build concrete roads on the main sections of the road, but the maintenance time is long and the cost is high. At the same time, the bending strength of ordinary concrete roads is low, and it is difficult to withstand heavy vehicle transportation of more than 100 tons. The road royal jelly or Louis enzyme products promoted abroad cannot be widely promoted in China due to cost reasons and raw material limitations. Therefore, there is an urgent need to develop a road material that can be quickly built, easily maintained, not prone to dust, and can be used on a large scale.

[0003] Using silicate components contained in solid wastes such as slag as a substitute for cement can greatly improve its early strength, and using the iron ions in slag to give it certain adsorption properties is a new way to recycle solid waste from mines. However, a single curing reaction only improves the compressive strength of the material, and cannot make it resistant to bending, so it is necessary to add organic polymer materials to it to improve its bending resistance and integrity. In addition, polymer materials such as polyacrylamide have obvious water absorption, which can effectively prevent cracks while absorbing soil particles. Therefore, double modification of existing waste soil and stone in mines by adding polymer organic materials and industrial solid waste is an effective way to simultaneously improve the bonding strength and flexural strength of soil-stone pavements.

[0004] In line with the needs of rapid construction and maintenance of open-pit mine transportation roads, existing waste soil and stone, solid waste and organic polymer materials are used to build a rapid road surface with compression resistance, wear resistance and bending strength. At the same time, it is given certain crack self-repairing properties, which can achieve the purpose of reducing open-pit mine production costs, increasing transportation speeds and extending the service life of the road surface. Summary of the invention

[0005] In view of the shortcomings of the current simple earth-stone roads in open-pit mines, the purpose of the present invention is to provide a self-repairing mine road material and its preparation method and application. The mine road material includes a main material, a modifier and a binder; the main material and the modifier are taken from mine solid waste, which is convenient to obtain. The binder can react with the modifier and the main material to produce alkali excitation, and does not produce organic substances. It is green and economical, and improves the early strength, water resistance and bending resistance of the open-pit mine transportation road, thereby increasing its service life. At the same time, the present invention uses polyacrylamide and polyvinyl alcohol as the main materials of the binder, which can absorb water repeatedly, so that the road surface has certain crack self-repairing properties, and adsorbs soil particles to form a film, greatly reducing the possibility of road dust.

[0006] In order to solve the problems of the prior art, the present invention provides the following technical solutions:

[0007] The self-repairable mine road material provided by the present invention comprises a main material, a solid modifier and a binder; the main material comprises blast pile slag and neutralized slag; the solid modifier is added in an amount of 5 to 10% of the total mass of the main material; the binder is a composite solution, the effective ingredients of which are polyvinyl alcohol and polyacrylamide, the mass ratio of the polyacrylamide to the polyvinyl alcohol is 1:10; the polyvinyl alcohol is added in an amount of 0.2 to 0.5% of the total mass of the main material; the polyacrylamide is added in an amount of 0.02 to 0.05% of the total mass of the main material.

[0008] Preferably, in the main material, the blasting slag is a low-grade waste ore produced by mining blasting activities, which may contain components such as copper, iron, sulfide, etc., but its unconfined compressive strength should be greater than 20MPa; the neutralized slag is the waste slag produced by neutralizing copper-acid wastewater with quicklime after drying for more than 7 days, which contains 5-10% calcium oxide, pH is 7-8, and the natural moisture content before use is less than 1%, is in powder form, has a solid mass fraction of 8-9%, a wet slag specific gravity of 1.01-1.05, a plastic limit of 21-25%, and a liquid limit of 60-65%; in the main material, the mass ratio of the blasting slag to the neutralized slag is 8:2-7:3.

[0009] Preferably, the solid modifier is composed of industrial active magnesium oxide and copper smelting slag powder in a mass ratio of 1:4 to 1:3; the industrial active magnesium oxide and copper smelting slag powder have different particle shapes, namely granular and powdery, and the particle sizes are both less than 120 meshes; the main component of the copper smelting slag powder is aluminosilicate, with an activity index of 90 to 105% and a plastic limit of 10 to 15%; the content of effective ingredients in the industrial active magnesium oxide is greater than 97%.

[0010] Preferably, the polyvinyl alcohol is powdered cationic polyvinyl alcohol, with a mesh size of not less than 120, a degree of polymerization of not less than 2400, a degree of alcoholysis of 88%, an active ingredient content of more than 98%, rapid dissolution by stirring at room temperature, and a viscosity of 50 to 60 mPa·s; the polyacrylamide is a zwitterionic type, with a mesh size of not less than 100, a molecular weight of more than 1000w, and an active ingredient content of not less than 99%.

[0011] The preparation method of the self-repairable mine road material is a pre-hydrolysis wet mixing method.

[0012] Preferably, the self-repairable mine road material is prepared by a pre-hydrolysis wet mixing method, comprising the following steps:

[0013] 1) Preparation of binder:

[0014] 1-1) Powdered polyvinyl alcohol is added to water above 4°C, and then modified polyether silicon is added as a defoamer, and stirred to prepare a polyvinyl alcohol solution with a mass concentration of w≤5%, and allowed to stand to allow the polyvinyl alcohol to fully swell;

[0015] 1-2) adding polyacrylamide to the swollen polyvinyl alcohol solution according to a set ratio, stirring, and obtaining a binder;

[0016] 2) The neutralized slag powder after drying and crushing is sieved, and the optimal moisture content w of the neutralized slag is obtained through compaction test. op , used for calculating the amount of water added in step 4); mixing the neutralized slag and the blasting slag according to a set ratio, stirring, and obtaining the main material;

[0017] 3) mixing industrial active magnesium oxide and copper smelting slag powder uniformly according to a set mass ratio to obtain a solid modifier;

[0018] 4) Add the solid modifier to the main material according to the given dosage and stir. During the stirring process, gradually add the binder and water. The amount of water added is m w =(w op ±2%)·m 渣 -w 粘 ·m 渣 / w, where m 渣 is the mass of the main material, w 粘 is the mass fraction of the given polyvinyl alcohol in the main material, w is the mass concentration of the prepared polyvinyl alcohol solution, and the mixture is mixed evenly to obtain a mixed pavement material;

[0019] 5) Use the compaction sampling method to compact the mixed pavement materials layer by layer, requiring the compaction degree to be ≥98% to obtain a compacted sample;

[0020] 6) Place the compacted sample in a constant temperature and humidity curing box, set the curing temperature to 22±1°C, the humidity to greater than 90%, and the curing time to 3 days. After the curing is completed, a self-repairable mine road material is obtained.

[0021] Preferably, in step 1-1), the mass of the modified polyether silicon is 0.05-0.1% of the mass of the polyvinyl alcohol powder; the stirring speed is 30-60 r / min, the stirring time is 6-12 h; and the standing time is 24-48 h.

[0022] Preferably, in step 1-2), the stirring speed is 30-60 r / min and the stirring time is 10 min.

[0023] Preferably, in the step 2), the neutralized slag powder after drying and crushing is passed through a 100-mesh standard sieve; the stirring speed is 60-120 r / min, and the stirring time is 5-10 min.

[0024] Preferably, in step 4), the stirring speed is 60 to 120 r / min, and the stirring time is 10 to 15 min.

[0025] The above-mentioned self-repairing mine road material is used in the flat road surface, steep slope section surface layer and surface layer repair of open-pit mine transportation roads.

[0026] Preferably, when the self-repairable mine road material is used as the pavement of the flat section of the open-pit mine transportation road, the total thickness of the pavement is set to 20 to 40 cm, including the following steps:

[0027] Step 1: According to the results of the preliminary survey report, determine the total thickness of the road surface, which should not be less than 20cm;

[0028] Step 2: Level the roadbed, fill in the pits on the roadbed, remove the bumps and debris on the roadbed surface, and check that the unevenness of the roadbed should be less than 50mm. Sprinkle a small amount of water on the roadbed surface to moisten it;

[0029] Step 3: using a factory mixing method and mechanical mixing, uniformly mixing the blasting slag and the neutralization slag according to a given ratio to obtain the main material;

[0030] Step 4: Use the factory mixing method to add solid modifier according to the given dosage, mechanically mix, add appropriate amount of binder and water during the mixing process to obtain the mixed pavement material, where the amount of water added is m w =(w op ±2%)·m 渣 -w 粘 ·m 渣 / w, where m 渣 is the mass of the main material, w 粘is the mass fraction of the given polyvinyl alcohol in the main material, and w is the mass concentration of the prepared polyvinyl alcohol solution;

[0031] Step 5: Roll in three layers, evenly lay the mixed pavement material on the roadbed, level it with a road grader, the loose laying thickness of a single layer is no more than 15 cm, the loose laying coefficient of each layer is 1.33, and let it stand for 3 to 6 hours;

[0032] Step 6: Compact with a 50t roller using a vibration compaction method. The roller travels at a speed of 1 to 2 km / h and compacts from low to high. During the travel process, ensure that the wheel tracks overlap by 1 / 4 to 1 / 3. The total number of compaction passes for each layer is not less than 3. Brush the surface with adhesive after compaction.

[0033] Step 7: Repeat steps 5 to 6 until the entire road surface is compacted;

[0034] Step 8: Do not open to traffic within 24 hours. During normal use, water should be sprinkled every 48 hours to keep the road surface moist so that small cracks can close.

[0035] Preferably, when the self-repairable mine road material is used as the surface layer of the steep slope section of the open-pit mine transportation road, the surface layer thickness is 5 to 10 cm, comprising the following steps:

[0036] Step 1: Lay the gravel base or inorganic mixture base, and determine the surface layer thickness according to the unevenness of the base, which should be more than 5cm higher than the highest point of the base surface;

[0037] Step 2: Brush adhesive on the surface of the base layer;

[0038] Step 3: using a factory mixing method and mechanical mixing, uniformly mixing the blasting slag and the neutralization slag according to a given ratio to obtain the main material;

[0039] Step 4: Use the factory mixing method to add solid modifier according to the given dosage, mechanically mix, add appropriate amount of binder and water during the mixing process, where the amount of water added is m w =(w op ±2%)·m 渣 -w 粘 ·m 渣 / w, where m 渣 is the mass of the main material, w 粘 is the mass fraction of the given polyvinyl alcohol in the main material, and w is the mass concentration of the prepared polyvinyl alcohol solution;

[0040] Step 5: Evenly spread the mixed pavement material on the roadbed and level it with a road grader. The loose paving thickness is not more than 15 cm, and the loose paving coefficient of each layer is 1.33. After standing for 3 to 6 hours, it is vibrated and compacted by a 50t roller for multiple times. The roller travels at a speed of 1 to 2 km / h and compacts from low to high. During the driving process, ensure that the wheel tracks overlap by 1 / 4 to 1 / 3, and the total number of compaction times is not less than 3 times;

[0041] Step 6: After the surface layer is compacted, seal it for 24 hours to obtain a self-repairing surface layer. During normal use, water should be sprinkled to keep the road surface moist so that small cracks can close.

[0042] Preferably, when the self-repairable mine road material is used as a surface repair material for an open-pit mine transport road, the unevenness of the damaged surface layer should be greater than 5 cm and not greater than 10 cm. The specific steps are as follows:

[0043] Step 1: Clear the unstable area around the damaged part of the repairable surface layer. The clearance boundary should be more than 1 cm larger than the unstable area.

[0044] Step 2: Apply adhesive on the surface;

[0045] Step 3: Evenly spread the mixed repairable road material on the damaged area, the height of which should be slightly higher than the road surface, and use a tamping rammer to perform vibration compaction. After the initial compaction, the surface should be slightly lower than the original road surface.

[0046] Step 4: Repeat steps 2 to 3 until the compacted surface is slightly higher than the original road surface by 0.5 to 1 cm;

[0047] Step 5: After the repair is completed, the area will be partially closed for 24 hours and then traffic will resume as normal.

[0048] The self-repairing mining road material has high bending strength, good integrity, and the characteristics of a flexible road surface; the self-repairing road material has high early strength and can be put into use after being closed for 24 hours under normal temperature conditions without special maintenance. It also has certain self-repairing properties, and small cracks can be closed after absorbing water and rolling, which reduces dust to a certain extent, reflecting extremely strong resistance to cracking and durability.

[0049] Compared with the prior art, the present invention has the following advantages:

[0050] 1) The present invention uses active magnesium oxide to provide an alkaline environment, and the copper smelting slag powder and polyvinyl alcohol undergo an alkali-induced reaction in an alkaline environment, thereby modifying the blast slag and the neutralized slag, improving the bonding strength and water stability of the consolidated body, and preventing the road surface from being muddy or dusty due to heavy rain erosion or wind erosion during service. At the same time, polyvinyl alcohol is used to adsorb soil particles on the road surface to form a water-resistant membrane structure, which prevents water from infiltrating the lower structure and maintains the overall strength of the road surface.

[0051] 2) Compared with ordinary solidified or cement materials, the present invention uses a binder to strengthen the bonding between particles while amplifying its flexibility, increasing the bending strength of the road surface, and ensuring that it can withstand high temperature-rainy-low temperature-dry cycles without damage, greatly improving its service life.

[0052] 3) The present invention forms a mutually non-repellent unified whole with cationic polyvinyl alcohol, zwitterionic polyacrylamide and soil. The good film-forming property of polyvinyl alcohol can prevent cracks from forming, while polyacrylamide can absorb water repeatedly, so that the small cracks that have been produced can close automatically under the action of pressure, thus actually forming a high-performance pavement material with crack self-repairing properties.

[0053] 4) The main material and solid modifier of the present invention are both mine solid wastes. After preparation, they form a unified whole, which can prevent harmful components such as sulfur and arsenic from dissolving and flowing into the soil or groundwater, and is an effective treatment and reuse of mine pollutants. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 This is a diagram showing the mechanism of action and application effect of a self-repairing mine road material, where 1-repairable road surface in flat sections, 2-repairable surface layer in steep slope sections, 3-gravel base layer, 4-surface layer repair, 5-heavy-duty ore truck, 6-blasting slag, 7-neutralized slag, 8-polyacrylamide, and 9-film-like polyvinyl alcohol;

[0055] Figure 2 A self-repairing mine road material is used in the construction flow chart of the flat section of the open-pit mine transportation road;

[0056] Figure 3 A self-repairing mine road material is used for the construction flow chart of the steep slope section of the open-pit mine transportation road surface;

[0057] Figure 4 The present invention is a construction flow chart of a self-repairing mine road material as a surface repair material. DETAILED DESCRIPTION

[0058] The present invention will be further described below in conjunction with specific embodiments.

[0059] In the following examples, the solid modifier used is composed of copper smelting slag powder and industrial active magnesium oxide powder in a mass ratio of 3:1, wherein: ① the copper smelting slag powder used is taken from a copper smelting enterprise in Longyan, Fujian, and its activity index is 99, the plastic limit is 12.1%, and it passes through a 120-mesh standard sieve; ② the industrial active magnesium oxide used is taken from an industrial enterprise in Zhenjiang, Jiangsu, and its effective ingredient content is 99%, and it passes through a 120-mesh standard sieve. The ingredients of the binder used include polyvinyl alcohol, polyacrylamide, and modified polyether silicone, among which: ① powdered cationic polyvinyl alcohol, with a mesh size of 120, a degree of polymerization of 2400, a degree of alcoholysis of 88%, an effective ingredient of 99%, which can be quickly dissolved by stirring at room temperature and has a viscosity of 51.6 mPa·s; ② zwitterionic polyacrylamide, produced by an enterprise in Zhengzhou, Henan, with a mesh size of 120, a molecular weight of 1200w, and an effective ingredient content of 99%; ③ ordinary modified polyether silicone, produced by a chemical enterprise in Zhangzhou, Fujian, with a dosage of 0.05% of the mass of polyvinyl alcohol. The main materials used include blasting slag and neutralized slag, and the mass ratio of each component is blasting slag: neutralized slag = 7:3, wherein: ① the blasting slag is taken from an open-pit mine in Shanghang, Fujian, contains copper, iron, sulfur and other components, and has an unconfined compressive strength of 36.7MPa; ② the neutralized slag is taken from a copper hydroprocessing plant of a mining enterprise in Shanghang, Fujian. After 10 days of drying, the natural moisture content before use is 0.5%, of which the calcium oxide content is 6.99%, the pH is 7.7, it is in powder form, the solid mass fraction is 8.37%, the wet slag specific gravity is 1.02, the plastic limit is 21.0%, and the liquid limit is 63.5%.

[0060] Example 1

[0061] A self-repairable mine road material comprises a main material, a solid modifier and a binder, wherein the main material is composed of blast pile slag and neutralized slag, and the mass ratio of blast pile slag: neutralized slag is 7:3; the solid modifier is composed of industrial active magnesium oxide powder and copper smelting slag powder, and the mass ratio is industrial active magnesium oxide: copper smelting slag powder = 1:3; the solid modifier is added in an amount of 5% of the total mass of the main material; the binder is prepared from polyvinyl alcohol, polyacrylamide, and modified polyether silicon, wherein the amount of polyvinyl alcohol is 0.3% of the total mass of the main material, the amount of polyacrylamide is 0.03% of the total mass of the main material, and the amount of modified polyether silicon is 0.05% of the mass of polyvinyl alcohol, and is prepared by a pre-hydrolysis wet mixing method, comprising the following steps:

[0062] 1) Powdered polyvinyl alcohol is added to water above 4°C, modified polyether silicon (the mass is 0.05% of the mass of polyvinyl alcohol powder) is added as a defoamer, and the mechanical stirrer is set to a stirring speed of 30r / min, stirred for 6 hours, and a 3% polyvinyl alcohol solution is prepared, and allowed to stand for 24 hours to allow the polyvinyl alcohol to fully swell;

[0063] 2) adding a certain amount of polyacrylamide to the polyvinyl alcohol solution, wherein the mass ratio of polyacrylamide to polyvinyl alcohol is 1:10, and setting the stirring speed of the mechanical stirrer to 30 r / min, and stirring for 10 minutes to obtain a concentrated binder;

[0064] 3) After drying and crushing, the neutralized slag powder is passed through a 100-mesh standard sieve, and the optimal moisture content w of the neutralized slag is obtained through a compaction test. op The neutralized slag and the blast pile slag are mixed in a mass ratio of blast pile slag: neutralized slag = 7:3, and stirred with a small drum mixer at a speed of 60r / min for 10min to obtain the main material;

[0065] 4) Prepare a solid modifier according to the mass ratio of industrial active magnesium oxide: copper smelting slag = 1:3, and mix the two evenly;

[0066] 5) Add 5% solid modifier to the main material and stir it with a small drum mixer. Set the speed to 120r / min. Add binder and a certain amount of water gradually during the stirring process. Stir for 15 minutes. Add water m w =(w op ±2%)*m 渣 -w 粘 *m 渣 / 3%, where m 渣 is the mass of the main material obtained in step 3), w 粘 The mass fraction of polyvinyl alcohol in the main material is given to be 0.3% in this embodiment, and the mixture is mixed evenly.

[0067] 6) The sample was compacted in three layers using the compaction method, with a compaction degree of 98%.

[0068] 7) The compacted sample is placed in a constant temperature and humidity curing box, the curing temperature is set to 22° C., the humidity is set to 91%, and the curing time is set to 3 days. After the curing is completed, a self-repairable mine road material is obtained.

[0069] Example 2

[0070] This embodiment is basically the same as the embodiment 1, except that the dosage of the solid modifier is 7.5% of the total mass of the main material, and the other conditions remain unchanged.

[0071] Example 3

[0072] This embodiment is basically the same as the embodiment 1, except that the amount of the solid modifier added is 10% of the total mass of the main material, and the other conditions remain unchanged.

[0073] Example 4

[0074] This embodiment is basically the same as the embodiment 1, except that the mass ratio of industrial active magnesium oxide: copper smelting slag powder is 1:4, the mass ratio of blasting slag: neutralization slag is 8:2, the dosage of the solid modifier is 7.5% of the total mass of the main material, and the other conditions remain unchanged.

[0075] Example 5

[0076] This embodiment is basically the same as embodiment 1, except that the amount of polyvinyl alcohol added is 0.2% of the total mass of the main material, the amount of polyacrylamide added is 0.02% of the total mass of the main material, the amount of solid modifier added is 7.5% of the total mass of the main material, and the other conditions remain unchanged.

[0077] Example 6

[0078] This embodiment is basically the same as embodiment 1, except that the amount of polyvinyl alcohol added is 0.5% of the total mass of the main material, the amount of polyacrylamide added is 0.05% of the total mass of the main material, the amount of solid modifier added is 7.5% of the total mass of the main material, and the other conditions remain unchanged.

[0079] Application Example 1

[0080] The self-repairable mine road pavement material of Example 2 was used for the flat section pavement of an open-pit mine transportation road in Shanghang, Fujian. The specific construction steps are as follows:

[0081] 1) According to the results of the preliminary investigation report, the total thickness of the pavement is determined to be 30cm;

[0082] 2) Level the roadbed, fill in the pits on the roadbed, remove the bumps and debris on the roadbed surface, detect the maximum unevenness of the roadbed to be 45mm, and sprinkle a small amount of water on the roadbed surface to moisten it;

[0083] 3) Using the factory mixing method and mechanical mixing, the blasting slag and the neutralization slag are evenly mixed in a mass ratio of 7:3 to obtain the main material;

[0084] 4) Use the factory mixing method, add solid modifier at a dosage of 7.5%, mix mechanically, add appropriate amount of binder and water during the mixing process, and the amount of water added is m w =(w op ±2%)*m 渣 -w 粘 *m 渣 / 3%, where m 渣 is the mass of the main material obtained in step 3), w 粘 is the mass fraction of the given polyvinyl alcohol in the main material;

[0085] 5) Roll the mixed pavement material evenly on the roadbed in three layers, level it with a road grader, the single layer loose paving thickness is 15cm, the loose paving coefficient of each layer is 1.33, and let it stand for 6 hours;

[0086] 6) Compacted by a 50t roller using the vibration compaction method, with the roller traveling at a speed of 1.5km / h, from low to high, with the wheel tracks overlapping by 1 / 4 to 1 / 3 during driving, with each layer compacted 3 times in total, and the surface brushed with adhesive after compaction;

[0087] 7) Repeat steps 5 to 6 until the entire road surface is compacted;

[0088] 8) Traffic will not be allowed for 24 hours. During normal use, water should be sprinkled every 48 hours to keep the road surface moist so that small cracks can close.

[0089] Application Example 2

[0090] The self-repairable mine road material of Example 2 is used for the surface layer of the steep slope section of an open-pit mine transportation road in Shanghang, Fujian. The specific construction steps are as follows:

[0091] 1) Lay a gravel base layer with a thickness of 30 cm and a surface layer with a thickness of 7 cm, which is 5 cm higher than the highest point of the base surface;

[0092] 2) Brush adhesive on the surface of the base layer;

[0093] 3) Using the factory mixing method and mechanical mixing, the blasting slag and the neutralization slag are evenly mixed in a mass ratio of 7:3 to obtain the main material;

[0094] 4) Use the factory mixing method, add solid modifier at a dosage of 7.5%, mix mechanically, add appropriate amount of binder and water during the mixing process, and the amount of water added is m w =(w op ±2%)*m 渣 -w 粘 *m 渣 / 3%, where m 渣 is the mass of the main material obtained in step 3), w 粘 is the mass fraction of the given polyvinyl alcohol in the main material;

[0095] 5) Evenly spread the mixed pavement material on the roadbed and level it with a road grader. The loose paving thickness is 10 cm and the loose paving coefficient of each layer is 1.33. After standing for 3 hours, use a 50t roller to vibrate and compact it 3 times. The roller travels at a speed of 1.5 km / h and compacts from low to high. During the driving process, ensure that the wheel tracks overlap by 1 / 4 to 1 / 3;

[0096] 6) After the surface layer is compacted, it should be sealed for 24 hours to obtain a self-repairing surface layer. During normal use, water should be sprinkled to keep the road surface moist so that small cracks can close.

[0097] Application Example 3

[0098] The self-repairable mine road material of Example 2 is used as a repair material for pits or defects generated during the surface layer construction process, and the steps are as follows:

[0099] 1) Clear the unstable area around the damaged part of the repairable surface layer, and the clearance boundary should be 3cm larger than the unstable area;

[0100] 2) Apply adhesive on the surface;

[0101] 3) Evenly lay the prepared repairable road material on the damaged area, its height should be slightly higher than the road surface, and use a tamping rammer to perform vibration compaction. After the initial compaction, the surface should be 3cm lower than the original road surface;

[0102] 4) Repeat steps 2 to 3 until the compacted surface is slightly higher than the original road surface by 1 cm;

[0103] 5) After the repair is completed, the area will be partially closed for 24 hours before it can be reopened to traffic.

[0104] Comparison Example

[0105] In order to compare the road performance indicators of unmodified simple mine soil and stone road, ordinary cement concrete road and the self-repairable mine road material of the present invention, and highlight the advantages of the present invention, unmodified simple mine soil and stone road and ordinary cement concrete road are set as control examples, named as control example T and control example C. The soil and stone used in control example T are neutralized slag and blast pile slag, and their performance parameters are the same as those in the embodiment and application example. They are unmodified and rolled by a 50t roller roller for 3 times. The soil and stone used in control example C are neutralized slag and blast pile slag, and their performance parameters are the same as those in the embodiment and application example. Ordinary silicate cement with a label of 42.5 is used for cementation, and the mass ratio of neutralized slag: blast pile slag: cement: water = 1:4:1:0.5, and the concrete pavement maintenance time is 7d.

[0106] Performance Testing

[0107] The self-repairable mine road materials in Examples 1-3, Control Example C, and Control Example T were compared by the following indoor tests:

[0108] 1) Unconfined compression test, the test standard refers to the "Standard for Geotechnical Test Methods" (GB / T2050123-2019) and "Highway Geotechnical Test Code" (JTGE 40-2007);

[0109] 2) Improved vacuum saturated Marshall test, the test standard refers to "Asphalt Mixture Marshall Stability Test" T0709-2000 and "Geotechnical Test Method Standard" (GB / T 2050123-2019);

[0110] 3) Flexible wall test, the test standards refer to ASTM D5887 and ASTM D5084;

[0111] 4) Flexural strength test, the test standard refers to "Test Code for Cement and Cement Concrete in Highway Engineering" (JTG3420-2020);

[0112] 5) Dry-wet cycle test, the test standard refers to ASTM D4843;

[0113] 6) Mercury intrusion test. The test standard refers to "Mercury Intrusion Intrusion and Gas Adsorption Method for Determination of Pore Size Distribution and Porosity of Solid Materials" (GB T 21650.1-2008).

[0114] The results are shown in Table 1.

[0115] Table 1 Indoor test results

[0116]

[0117] The effects of the self-repairable mine road materials in Examples 1 and 2, and Control Examples C and T were compared through the following field penetration tests:

[0118] Penetration test, the test standard refers to the "Technical Code for Testing the Compressive Strength of Masonry Mortar by Penetration Method (JGJT136-2001)"; the results are shown in Table 2.

[0119] Table 2 Field test results

[0120]

[0121] The above test results show that, compared with the unmodified simple earth-stone road, the self-repairable mine road material of the present invention has a higher water stability index, unconfined compressive strength and limit dry-wet cycle number, and at the same time, its porosity and permeability coefficient are significantly reduced. Compared with ordinary concrete roads, the present invention has higher early strength, and its water resistance and bending resistance are significantly better, and its 3d bending strength can be increased by 32 to 107%. At the same time, the field application test results show that after the modification of the present invention, the bonding strength between soil particles is significantly improved, and its 3d penetration strength can be increased by more than 30 times relative to the earth-stone road, and can also be increased by more than 30% relative to the ordinary concrete road. In summary, the self-repairable mine road material of the present invention has improved compressive strength, water stability, impermeability and durability relative to the unmodified simple earth-stone road, and improved bending resistance and early strength relative to the general concrete road, showing good road performance and service effect suitable for heavy loads in mines.

[0122] The above description is only a more preferred specific implementation manner of the present invention, and the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make several improvements and modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A self-repairable mine road material, characterized in that: The self-repairable mine road material is composed of a main material, a solid modifier and a binder; the main material includes blasting slag and neutralization slag; the blasting slag is a low-grade waste ore produced by mining blasting activities, with a particle size of 1-2 cm and an unconfined compressive strength greater than 20 MPa; the neutralization slag is a waste slag produced by neutralizing copper acid wastewater with quicklime after drying for more than 7 days, and contains 5-10% calcium oxide; in the main material, the mass ratio of blasting slag to neutralization slag is 8:2-7:3 ; The solid modifier is composed of industrial active magnesium oxide and copper smelting slag powder in a mass ratio of 1:4~1:3; the components of the copper smelting slag powder include aluminosilicate; the dosage of the solid modifier is 5~10% of the total mass of the main material; the binder is a composite solution, and the effective ingredients are polyvinyl alcohol and polyacrylamide; the dosage of the polyvinyl alcohol is 0.2~0.5% of the total mass of the main material; the dosage of the polyacrylamide is 0.02~0.05% of the total mass of the main material.

2. The self-repairable mine road material according to claim 1, characterized in that: The pH of the neutralized slag is 7-8, the natural moisture content before use is less than 1%, the slag is in powder form, the solid mass fraction is 8-9%, the wet slag specific gravity is 1.01-1.05, the plastic limit is 21-25%, and the liquid limit is 60-65%.

3. The self-repairable mine road material according to claim 1, characterized in that: The particle sizes of the industrial active magnesium oxide and copper smelting slag powder are both less than 120 meshes; the copper smelting slag powder comprises aluminum silicate, with an activity index of 90-105% and a plastic limit of 10-15%; the effective ingredient content of the industrial active magnesium oxide is greater than 97%.

4. The self-repairable mine road material according to claim 1, characterized in that: The polyvinyl alcohol is powdered cationic polyvinyl alcohol, with a mesh size of not less than 120, a degree of polymerization of not less than 2400, a degree of alcoholysis of 88%, an effective component content of more than 98%, rapid dissolution by stirring at room temperature, and a viscosity of 50-60 mPa·s; the polyacrylamide is a zwitterionic type, with a mesh size of not less than 100, a molecular weight of more than 1000w, and an effective component content of more than 99%.

5. A method for preparing the self-repairable mine road material according to any one of claims 1 to 4 is a pre-hydrolysis wet mixing method, which specifically comprises the following steps: 1) Preparation of binder: 1-1) Add powdered polyvinyl alcohol to water above 4°C, then add modified polyether silicone as defoamer, stir, and prepare to a mass concentration of w ≤5% polyvinyl alcohol solution, let it stand to allow the polyvinyl alcohol to fully swell; 1-2) Adding polyacrylamide to the swollen polyvinyl alcohol solution according to a set ratio, stirring, and obtaining a binder; 2) After drying and crushing, the neutralized slag powder is sieved and the optimal moisture content of the neutralized slag is obtained through compaction test. w op , used for calculating the amount of water added in step 4); mixing the neutralized slag and the blasting slag according to a set ratio, stirring, and obtaining the main material; 3) mixing industrial active magnesium oxide and copper smelting slag powder evenly according to a set mass ratio to obtain a solid modifier; 4) Add the solid modifier to the main material according to the given dosage, stir, and gradually add the binder and water during the stirring process. m w =( w op ±2%) m 渣 - w 粘 · m 渣 / w ,in m 渣 The quality of the main material, w 粘 is the mass fraction of the given polyvinyl alcohol in the main material, w The mass concentration of the prepared polyvinyl alcohol solution is set, and the mixture is mixed evenly to obtain a mixed pavement material; 5) Use the compaction sampling method to compact the mixed pavement materials in three layers, with a compaction degree of ≥98% to obtain a compacted sample; 6) Place the compacted sample in a constant temperature and humidity curing box, set the curing temperature to 22±1℃, the humidity to greater than 90%, and the curing time to 3 days. After the curing is completed, a self-repairing mine road material is obtained.

6. The preparation method according to claim 5, characterized in that: In the step 1-1), the mass of the modified polyether silicon is 0.05-0.1% of the mass of the polyvinyl alcohol powder; the stirring speed is 30-60 r / min, the stirring time is 6-12 h; and the standing time is 24-48 h.

7. Use of the self-repairable mine road material prepared according to the preparation method of claim 5 or 6 in the flat section pavement, steep slope section surface layer and surface layer repair of open-pit mine transportation roads.

8. The use according to claim 7, when the self-repairable mine road material is used as the pavement of the flat section of the open-pit mine transportation road, the total thickness of the pavement is set to 20-40 cm, comprising the following steps: Step 1: According to the results of the preliminary survey report, determine the total thickness of the road surface, which should not be less than 20cm; Step 2: Level the roadbed, fill in the pits on the roadbed, remove the bumps and debris on the roadbed surface, and check that the unevenness of the roadbed should be less than 50mm. Sprinkle a small amount of water on the roadbed surface to moisten it; Step 3: using a factory mixing method and mechanical mixing, uniformly mixing the blasting slag and the neutralization slag according to a given ratio to obtain the main material; Step 4: Use the factory mixing method to add solid modifier according to the given dosage, mechanically mix, add appropriate amount of binder and water during the mixing process to obtain the mixed pavement material, where the amount of water added is m w =( w op ±2%) m 渣 - w 粘 · m 渣 / w ,in m 渣 The quality of the main material, w 粘 is the mass fraction of the given polyvinyl alcohol in the main material, w is the mass concentration of the prepared polyvinyl alcohol solution; Step 5: Roll in three layers, evenly lay the mixed pavement material on the roadbed, level it with a road grader, the loose laying thickness of a single layer is no more than 15 cm, the loose laying coefficient of each layer is 1.33, and let it stand for 3 to 6 hours; Step 6: Compact with a 50t roller using a vibration compaction method. The roller travels at a speed of 1-2 km / h and compacts from low to high. During the travel process, ensure that the wheel tracks overlap by 1 / 4-1 / 3. The total number of compaction passes for each layer is not less than 3 times. After compaction, apply adhesive to the surface. Step 7: Repeat steps 5 and 6 until the entire road surface is compacted; Step 8: Do not open to traffic within 24 hours. During normal use, water should be sprinkled every 48 hours to keep the road surface moist so that small cracks can close.

9. The use according to claim 7, when the self-repairable mine road material is used as the surface layer of the steep slope section of the open-pit mine transportation road, the surface layer thickness is 5-10 cm, comprising the following steps: Step 1: Lay the gravel base or inorganic mixture base, and determine the surface layer thickness according to the unevenness of the base, which should be more than 5cm higher than the highest point of the base surface; Step 2: Brush adhesive on the surface of the base layer; Step 3: using a factory mixing method and mechanical mixing, uniformly mixing the blasting slag and the neutralization slag according to a given ratio to obtain the main material; Step 4: Use the factory mixing method to add solid modifier according to the given dosage, mechanically mix, add appropriate amount of binder and water during the mixing process, where the amount of water added is m w =( w op ±2%) m 渣 - w 粘 · m 渣 / w ,in m 渣 The quality of the main material, w 粘 is the mass fraction of the given polyvinyl alcohol in the main material, w is the mass concentration of the prepared polyvinyl alcohol solution; Step 5: Evenly lay the mixed pavement material on the roadbed and level it with a road grader. The loose paving thickness is not more than 15 cm, and the loose paving coefficient of each layer is 1.

33. After standing for 3 to 6 hours, use a 50t roller to vibrate and compact it multiple times. The roller travels at a speed of 1 to 2 km / h and compacts from low to high. During the driving process, ensure that the wheel tracks overlap by 1 / 4 to 1 / 3, and the total number of compaction times is not less than 3 times; Step 6: After the surface layer is compacted, seal it for 24 hours to obtain a self-repairing surface layer. During normal use, water should be sprinkled to keep the road surface moist so that small cracks can close.

10. The use according to claim 7, when the self-repairable mine road material is used as a surface repair material for open-pit mine transportation roads, the unevenness of the damaged surface layer should be greater than 5 cm and not greater than 10 cm, specifically comprising the following steps: Step 1: Clear the unstable area around the damaged part of the repairable surface layer. The clearance boundary should be more than 1 cm larger than the unstable area. Step 2: Apply adhesive on the surface; Step 3: Evenly spread the mixed repairable road material on the damaged area, the height of which should be slightly higher than the road surface, and use a tamping rammer to perform vibration compaction. After the initial compaction, the surface should be slightly lower than the original road surface. Step 4: Repeat steps 2 and 3 until the compacted surface is slightly higher than the original road surface by 0.5 to 1 cm; Step 5: After the repair is completed, the area will be partially closed for 24 hours and then traffic will resume as normal.

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