Construction method of permeable interlocking piles for improving the stability of tailings ponds

Abstract

The invention provides a construction method of permeable interlocking piles for improving the stability of a tailings pond, comprising the following steps: S1: constructing the main body of the permeable piles; S2: heating and curing the permeable piles obtained in S1; S3: reheating the permeable piles obtained in S2 to form a permeable structure; S4: continuously repeating the permeable pile construction, permeable pile heating and curing, and permeable pile reheating processes to obtain a permeable interlocking pile wall. The invention solves the problem that the existing tailings pond reinforcement method reduces the permeability of the tailings and is too costly and slow.

Description

Technical Field

[0001] The invention belongs to the technical field of geotechnical engineering, and in particular relates to a construction method of permeable interlocking piles for improving the stability of a tailings pond. Background Art

[0002] Tailings ponds are artificial structures used to store tailings, waste rock and wastewater generated during the mining process. Tailings ponds usually have high potential energy, and the waste in the tailings ponds has a certain fluidity, which is easily affected by external factors such as rain and earthquakes, resulting in the stability of the tailings pond being threatened. Once it loses stability, it will cause devastating damage to human life, property and the ecological environment in a large area downstream.

[0003] At present, there are two main methods to improve the stability of tailings ponds: one is to use slope reinforcement technology, such as setting up retaining walls, slope protection and other structures, grouting reinforcement, anchor reinforcement, etc. to improve slope stability; the other is to use pile technology in the reservoir. However, the existing slope reinforcement technology has a serious impact on the permeability of the tailings pond, which can easily lead to a decrease in overall permeability and an increase in the infiltration line, which poses a secondary threat to the stability of the dam body; the piles in the tailings pond generally use gravel piles or concrete piles. The gravel pile construction requires a large amount of sand and gravel to be transported outside, which is costly and slow to construct. The tailings in the reservoir cannot be used, and the construction process of concrete piles also has a great impact on the permeability of the tailings. Summary of the invention

[0004] The object of the present invention is to provide a construction method of permeable interlocking piles for improving the stability of a tailings pond, so as to solve the problems that the existing tailings pond reinforcement method reduces the permeability of the tailings pond and is too costly and slow.

[0005] The technical solution adopted by the present invention is:

[0006] The construction method of permeable interlocking piles for improving the stability of tailings ponds comprises the following steps:

[0007] S1: Carry out the main construction of permeable piles;

[0008] S2: heating and curing the permeable pile obtained in S1;

[0009] S3: reheating the permeable pile obtained in S2 to form a permeable structure;

[0010] S4: Continuously repeat the process of permeable pile construction, permeable pile heating and curing, and permeable pile secondary heating to obtain a permeable interlocking pile wall.

[0011] Further, the S1 includes:

[0012] S11: Construction preparation: Install the pressure sensor on the drill pipe; a mixing head is fixedly installed at one end of the drill pipe, and the probe of the pressure sensor is fixedly installed inside the mixing head; the other end of the drill pipe is fixedly connected to the ground drive device and the control console; a channel is set inside the drill pipe, the channel passes through the mixing head, the end of the channel is a grouting hole, the first end of the channel is fixedly connected to the pumping device, the pumping device is connected to the slurry barrel through a pipeline, and the slurry barrel is respectively connected to the aggregate barrel and the liquid collection barrel through pipelines; the control console is respectively connected to the aggregate barrel, the liquid collection barrel, the pumping device, and the mixing head; cement, tailings, and high molecular polymer particles are placed in the aggregate barrel, and water is placed in the liquid collection barrel;

[0013] S12: Before construction, calculate the contents of cement, water, polymer particles, and tailings and obtain polymer particles;

[0014] S13: Start construction, in the accumulation dam containing tailings, according to the setting position of the permeable pile, rotate the mixing head into the tailings;

[0015] S14: The control console adjusts the rotation speed of the mixing head, the power output of the ground driving device, and the descent rate of the drill pipe according to the descending resistance of the mixing head fed back by the pressure sensor;

[0016] S15: During the construction process, when the mixing head is screwed into the tailings to a predetermined depth, the control console controls the switches of the aggregate bucket and the liquid collection bucket, and adjusts the contents of cement, water, polymer particles, and tailings according to the screw-in depth and the volume content ratio of cement, water, polymer particles, and tailings calculated in S12; cement and water form a slurry; cement, water, polymer particles, and tailings form a mixture;

[0017] S16: Start the pumping device, which pumps the mixture into the mixing device and starts grouting through the grouting holes at the bottom of the mixing head. At the same time, the mixing head starts stirring and slowly rises;

[0018] S17: The mixing head is gradually lifted until it leaves the tailings surface, completing the construction of the main body of the permeable pile.

[0019] Furthermore, in said S12,

[0020] According to the screw-in depth and the tailings particle size, the contents of cement, water, polymer particles and tailings are calculated; the polymer is made into a foam plastic sheet by a foam plastic thermoforming method, and then the polymer particles having the same particle size range as the tailings particle size range are obtained by cutting and particle size screening operations;

[0021] Furthermore, in said S12,

[0022] When the screwing depth of the mixing head is 0~20m, the particle size of the polymer particles is 2.0~10.0mm, and the volume content of the polymer particles is 6~8%. At this time, the volume content of cement is 18~20%, the volume content of water is 18~22%, and the volume content of tailings is 50~58%;

[0023] When the screw-in depth is 20-40m, the particle size of the polymer particles is 1.0-5.0mm, and the volume content of the polymer particles is 5-7%. At this time, the volume content of cement is 14-16%, the volume content of water is 14-18%, and the volume content of tailings is 59-67%.

[0024] When the penetration depth is 40~60m, the particle size of the polymer particles is 0.5~2.0mm, and the volume content of the polymer particles is 3~5%. At this time, the volume content of cement is 9~11%, the volume content of water is 9~13%, and the volume content of tailings is 71~79%.

[0025] Furthermore, in S16,

[0026] The control console controls the pumping pressure of the pumping device according to the descending resistance of the stirring head fed back by the pressure sensor.

[0027] Further, the S2 includes:

[0028] S21: burying the electromagnetic cage at a position centered on the central axis of the permeable pile, and pressing the electromagnetic cage as a whole into the permeable pile;

[0029] S22: Install a temperature probe on the heating tube and press the heating tube into the center of the permeable pile. The electromagnetic cage is energized to increase the temperature of the heating tube and accelerate the solidification of the pile body.

[0030] Furthermore, in S21,

[0031] The electromagnetic cage is buried by vibration.

[0032] Furthermore, in S22, the curing temperature, i.e., the heating temperature of the heating tube, is monitored, and the curing temperature is controlled to be 10-40° C. by adjusting the current passing through the electromagnetic cage.

[0033] Further, the S3 includes:

[0034] S31: raising the heating temperature of the heating tube to a temperature higher than the thermal decomposition temperature of the polymer particles for secondary heating;

[0035] Calculate the heating time t required for the entire permeable pile body to reach the thermal decomposition temperature. The calculation formula is:

[0036]

[0037] in, is the thermal conductivity of the permeable pile, is the heat capacity of the material, is the ambient temperature, is the radius of the permeable pile, is the target temperature, is the initial temperature of the pile;

[0038] S32: The time required for the secondary heating process is (t+30)~(t+35)min;

[0039] S33: After the time required for the secondary heating process is reached, the structure of the polymer particles is destroyed and collapsed to form water-permeable pores;

[0040] S34: Pull out the heating tube to complete the secondary heating of the permeable pile.

[0041] Further, the S4 includes:

[0042] S41: According to the preset pile wall direction, the construction of the main body of the permeable pile is continuously completed; adjacent permeable piles are engaged with each other to form a pile wall;

[0043] S42: After completing the main body construction of the second permeable pile, heat and solidify the first permeable pile and perform secondary heating; after completing the main body construction of the third permeable pile, heat and solidify the second permeable pile and perform secondary heating, and repeat this sequence until all the permeable piles are heated, solidified and heated again.

[0044] The beneficial effects of the present invention are:

[0045] 1. In the present invention, prefabricated high molecular polymer particles, tailings and slurry are fully mixed by a stirring head, inserted into an annular electromagnetic cage by an oscillation method, and then a heating tube is inserted into the middle of the pile body to accelerate the pile formation by heating and curing, and then a new pile is completed at a predetermined adjacent position, with a certain overlap area between the two piles. This process is repeated to form a permeable interlocking pile, which can effectively improve the overall shear strength and stability of the tailings pond and reduce the risk of dam break of the tailings pond.

[0046] 2. In the present invention, after solidifying into a pile, the high molecular polymer is collapsed by secondary heating to form a permeable channel, thus forming a water-permeable interlocking pile, which improves the stability and enhances the permeability of the pile body.

[0047] 3. Compared with traditional reinforcement materials, the permeable interlocking piles of the present invention can effectively utilize tailings sand and save costs; high molecular polymers have the advantages of low cost and non-toxicity.

[0048] 4. In the process of heating and curing, the electromagnetic cage is buried in the permeable pile, the heating tube is pressed into the permeable pile, and the curing is accelerated by thermal radiation, thereby significantly shortening the curing time and improving the pile-forming efficiency. Compared with the existing pile-forming technology, the construction period can be greatly shortened.

[0049] 5. In the existing pile-making technology, the general method for reinforcing the pile body is to consider adding various auxiliary materials to increase the overall strength, which will greatly reduce the permeability or even make it impermeable. However, for most tailings ponds, the waterproof reinforcement will cause the infiltration line in the tailings pond to rise rapidly, causing an extremely adverse negative impact on the stability of the tailings pond. Therefore, the present invention is to heat the pile body after solidification, so that the added material undergoes thermal decomposition and collapse to form local small cavities, thereby enhancing the permeability of the pile body. However, the strength of the pile body will be weakened in this process, which is exactly the opposite of the method usually required by people in this field to ensure the completion and strength of the pile.

[0050] 6. The method of the present invention is simple, convenient, environmentally friendly, and will not cause secondary pollution to the ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0052] Figure 1 It is a schematic diagram of pile formation of the tailings pond of the present invention.

[0053] Figure 2 It is a diagram of a permeable pile construction equipment of the present invention.

[0054] Figure 3 Schematic diagram of the mixture of the present invention, wherein A is a schematic diagram of the mixture before heating and curing, and B is a schematic diagram of the mixture after heating and curing.

[0055] Figure 4 It is a structural diagram of a drill rod of the present invention.

[0056] Figure 5 This is a construction effect diagram after the electromagnetic cage of the present invention is buried in a permeable pile.

[0057] Figure 6 It is a schematic diagram of secondary curing of the permeable pile of the present invention.

[0058] Figure 7 It is a structural diagram of an electromagnetic cage of the present invention.

[0059] Figure 8It is a pile wall construction effect diagram of the present invention.

[0060] In the figure, 1, mixing head, 2, grouting hole, 3, pressure sensor, 4, permeable pile, 5, control console, 6, pumping device, 7, slurry barrel, 8, aggregate barrel, 9, liquid collecting barrel, 10, heating pipe, 11, tailings, 12, electromagnetic cage, 13, slurry, 14, high molecular polymer particles. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] The complete steps of the method of the present invention are as follows:

[0063] S1: Construction of the main body of the permeable pile. The specific steps are as follows:

[0064] See also Figure 1-Figure 8 The main construction equipment of the permeable pile includes a mixing head 1, a pressure sensor 3, a control console 5, a slurry barrel 7, a pumping device 6, a collection barrel 8, and a liquid collection barrel 9.

[0065] S11: Construction preparation. The pressure sensor 3 is installed on the drill rod, and the drill rod can transmit the propulsion force; the mixing head 1 is fixedly installed at one end of the drill rod, and the probe of the pressure sensor 3 is fixedly installed inside the mixing head 1; the other end of the drill rod is fixedly connected to the ground drive device and the control console 5. A channel is set inside the drill rod, and the channel passes through the mixing head 1. The end of the channel is a grouting hole 2. The head end of the channel is fixedly connected to the pumping device 6, and the pumping device 6 is connected to the slurry barrel 7 through a pipeline. The slurry barrel 7 is respectively connected to the aggregate barrel 8 and the liquid collecting barrel 9 through pipelines; the control console 5 is respectively connected to the aggregate barrel 8, the liquid collecting barrel 9, the pumping device 6, and the mixing head 1; cement, tailings, and high molecular polymer particles are placed in the aggregate barrel 8, and water is placed in the liquid collecting barrel 9, and cement and water form a slurry 13; the control console 5 is connected to the aggregate barrel 8 and the liquid collecting barrel 9 to control the switches of the aggregate barrel 8 and the liquid collecting barrel 9.

[0066] S12: Before pile making, the contents of cement, water and polymer particles 14 are calculated according to the screw-in depth and the particle size of the tailings 11. In this embodiment, polycarbonate is selected to prepare the polymer particles 14. The preparation method is: first, the polymer polycarbonate is made into a foam plastic sheet by a foam plastic thermoforming method, and then the desired polymer particles 14 of different particle sizes are obtained by cutting and particle size screening operations.

[0067] Specifically, before making piles, it is necessary to analyze the particle size of tailings at different depths. In order to improve permeability, the polymer needs to match the grading of the tailings sand and occupy a relatively large volume in the grading, thereby forming a relatively large support structure. The polymer grading generally needs to account for 3% to 8% of the total volume of the tailings.

[0068] When the screwing depth of the mixing head 1 is 0-20m, the particle size of the polymer particles 14 is 2.0-10.0mm, and the volume content of the polymer particles 14 is 6-8%. At this time, the volume content of cement is 18-20%, the volume content of water is 18-22%, and the volume content of tailings is 50-58%.

[0069] When the screwing depth is 20-40 m, the particle size of the polymer particles 14 is 1.0-5.0 mm, and the volume content of the polymer particles 14 is 5-7%. At this time, the volume content of cement is 14-16%, the volume content of water is 14-18%, and the volume content of tailings is 59-67%.

[0070] When the screwing depth is 40-60m, the particle size of the polymer particles 14 is 0.5-2.0mm, and the volume content of the polymer particles 14 is 3-5%. At this time, the volume content of cement is 9-11%, the volume content of water is 9-13%, and the volume content of tailings is 71-79%.

[0071] S13: Start construction: In the accumulation dam containing tailings 11 , according to the set position of the permeable pile 4 , the mixing head 1 is screwed into the tailings 11 .

[0072] S14: The control console 5 adjusts the rotation speed of the mixing head 1 , the power output of the ground drive device, and the descent rate of the drill pipe according to the descending resistance of the mixing head 1 fed back by the pressure sensor 3 , to ensure that the mixing head 1 can be smoothly rotated into the tailings 11 .

[0073] S15: During the construction process, when the mixing head 1 is screwed into the tailings 11 to a predetermined depth, the control console 5 controls the switches of the aggregate barrel 8 and the liquid collecting barrel 9, and adjusts the contents of cement, water, high molecular polymer particles 14 and tailings 11 in the mixture in the slurry barrel 7 according to the screwing depth and the volume content ratio of cement, water, high molecular polymer particles 14 and tailings 11 calculated in S12; cement and water form a slurry 13;

[0074] S16: Start the pumping device, the pumping device 6 pumps the mixture, and starts grouting through the grouting hole 2 at the bottom of the mixing head 1. At the same time, the mixing head 1 starts to stir and slowly rises. The control console 5 controls the pressurization or decompression of the pumping device 6 according to the resistance feedback from the pressure sensor 3, and adjusts the pumping pressure; the greater the resistance, the greater the required pumping pressure, otherwise the mixture cannot be pumped in.

[0075] S17: The mixing head 1 is gradually lifted until it leaves the surface of the tailings 11, and the construction of the main body of the permeable pile 4 is completed.

[0076] S2: Heating and curing. The specific steps are as follows:

[0077] S21: See Figure 5-7 The electromagnetic cage 12 is buried at a position centered on the central axis of the permeable pile 4 by vibration, and the electromagnetic cage 12 is pressed into the permeable pile 4 as a whole to become a part of the permeable pile 4, which can increase the strength of the permeable pile 4.

[0078] S22: Install a temperature probe on the heating tube 10 and press the heating tube 10 into the center of the main body of the permeable pile 4. After the electromagnetic cage 12 is powered on, the generated alternating magnetic field will increase the temperature of the heating tube 10 through electromagnetic induction, and accelerate the curing of the pile body through the heat radiation of the heating tube 10. Monitor the curing temperature, that is, the displayed temperature of the temperature probe on the heating tube 10, and control the curing temperature to 10~40℃ by adjusting the current passing through the electromagnetic cage 12. Too low temperature will delay the curing time; temperature above 40℃ will affect the strength of the cured structure.

[0079] S3: Secondary heating to form a water-permeable structure. The specific steps are as follows:

[0080] S31: See Figure 3 , wherein A is a schematic diagram of the mixture before heating and curing, and B is a schematic diagram of the mixture after heating and curing. After completing S2 heating and curing, the heating temperature is increased. The temperature needs to exceed the temperature at which the polymer undergoes thermal decomposition. Different types of polymers have different thermal decomposition temperatures. In this embodiment, when the temperature exceeds the heat resistance limit of polycarbonate, 300°C, that is, the target temperature is 300°C, the polycarbonate will undergo thermal decomposition.

[0081] At the same time, the transfer of heat requires a medium and time. In order to thermally decompose all the polymer particles 14 in the permeable pile 4, the heat needs to be fully transferred. The time for the pile body to reach the target temperature is t, and the calculation formula is as follows:

[0082] The formula for the heating time t required for the pile body to reach the pyrolysis temperature is:

[0083] ,

[0084] Among them, the thermal conductivity of the permeable pile is , the heat capacity of the material is , the ambient temperature is , The radius of the permeable pile is In this embodiment, the pile radius is 0.5-0.8 m; the target temperature is , The initial temperature of the pile is ;

[0085] S32: According to the test results, it takes 30 to 35 minutes to fully pyrolyze the pile body after reaching the pyrolysis temperature. That is, the overall time required for the secondary heating process is (t+30) to (t+35) min, ensuring that the pile body can be fully pyrolyzed.

[0086] S33: After the pile body is fully pyrolyzed as a whole, the structure of the polymer particles 14 is destroyed and collapsed, and water-permeable holes are formed. This is because heating can accelerate the solidification of the slurry 13, the tailings 11, and the polymer particles 14 to form a whole, but the polymer particles 14 have a pyrolysis temperature. After exceeding the pyrolysis temperature, the molecular structure of the polymer particles 14 will be destroyed and collapse into a ball. For a pile body that has been cured, increasing the temperature has limited effect on the strength of the pile body. Taking slag silicate cement as an example, its heat resistance limit is 800°C, which is far higher than the temperature at which general polymers pyrolyze, so secondary heating has little effect on other substances.

[0087] S34: Pull out the heating tube 10 to complete the secondary heating of the permeable pile 4.

[0088] Carry out strength testing, and the pile body strength after pile formation must be greater than 0.5MPa to meet the stability requirements of the tailings pond.

[0089] S4: Pile wall construction.

[0090] S41: See Figure 8 According to the preset pile wall direction, the construction of the main body of the permeable pile 4 is completed continuously, and it is necessary to ensure that there is a certain overlap area between adjacent permeable piles 4; the permeable piles 4 are interlocked with each other to form a pile wall.

[0091] S42: After the main body construction of the second permeable pile 4 is completed, the first permeable pile 4 is heated and cured; after the main body construction of the third permeable pile 4 is completed, the second permeable pile 4 is heated and cured, and this sequence is repeated until all the permeable piles 4 are heated and cured. The purpose of this is to sequentially cure and reduce consumption time.

[0092] Example 1

[0093] S1: Construction of main body of permeable piles.

[0094] S11: Construction preparation: The pressure sensor 3 is installed on the drill pipe, and the permeable pile 4 is selected and set in the accumulation dam.

[0095] S12: Before making piles, the particle size analysis of tailings at different depths is required. In order to improve the permeability, the polymer needs to match the grading of the tailings sand;

[0096] When the screwing depth is 0-20m, the particle size of the polymer particles 14 is 6mm, the volume content of the polymer particles 14 is 7%, the volume content of cement is 19%, the volume content of water is 19%, and the volume content of the tailings 11 is 55%;

[0097] When the screwing depth is 20-40 m, the particle size of the polymer particles 14 is 3 mm, the volume content of the polymer particles 14 is 6%, the volume content of the cement is 15%, the volume content of the water is 15%, and the volume content of the tailings 11 is 64%;

[0098] When the penetration depth is 40-60 m, the particle size of the high molecular polymer particles 14 is 1 mm, the volume content of the high molecular polymer particles 14 is 4%, the volume content of cement is 10%, the volume content of water is 10%, and the volume content of tailings 11 is 76%.

[0099] S13: Start construction: In the accumulation dam containing tailings 11 , according to the set position of the permeable pile 4 , the mixing head 1 is screwed into the tailings 11 .

[0100] S14: The control console 5 adjusts the rotation speed of the mixing head 1 , the power output of the ground drive device, and the descent rate of the drill pipe according to the descending resistance of the mixing head 1 fed back by the pressure sensor 3 , to ensure that the mixing head 1 can be smoothly rotated into the tailings 11 .

[0101] S15: During the construction process, when the mixing head 1 is screwed into the tailings 11 to a predetermined depth, the control console 5 controls the switches of the aggregate barrel 8 and the liquid collecting barrel 9, and adjusts the contents of cement, water, polymer particles 14 and tailings 11 in the mixture in the slurry barrel 7 according to the screw-in depth and the volume content ratio of cement, water, polymer particles 14 and tailings 11 calculated in S12.

[0102] S16: Start the pumping device, the pumping device 6 pumps the mixture, and starts grouting through the grouting hole 2 at the bottom of the mixing head 1. At the same time, the mixing head 1 starts to stir and slowly rises. The control console 5 controls the pressurization or decompression of the pumping device 6 according to the resistance feedback from the pressure sensor 3 to adjust the pumping pressure.

[0103] S17: The mixing head 1 is gradually lifted until it leaves the surface of the tailings 11, and the construction of the main body of the permeable pile 4 is completed.

[0104] S2: Heating and curing. The specific steps are as follows:

[0105] S21: The electromagnetic cage 12 is buried at a position centered on the central axis of the permeable pile by vibration, and the electromagnetic cage 12 is pressed into the permeable pile 4 as a whole to become a part of the permeable pile 4, thereby increasing the strength of the permeable pile 4.

[0106] S22: Install a temperature probe on the heating tube 10 and press the heating tube 10 into the center of the main body of the permeable pile 4. After the electromagnetic cage 12 is powered on, the generated alternating magnetic field will increase the temperature of the heating tube 10 through electromagnetic induction, and accelerate the curing of the pile body through the heat radiation of the heating tube 10. Monitor the curing temperature, that is, the temperature displayed by the temperature probe on the heating tube 10, and control the curing temperature to 25°C by adjusting the current passing through the electromagnetic cage 12.

[0107] S3: Secondary heating to form a water-permeable structure.

[0108] S31: Calculate the time t for the pile body to reach the target temperature.

[0109] S32: After reaching the pyrolysis temperature, the secondary heating process needs to be maintained for (t+32) min to ensure that the pile body can be fully pyrolyzed.

[0110] S33: After the pile body is fully pyrolyzed, the structure of the polymer particles 14 is destroyed and collapsed to form water-permeable holes. This is because heating can accelerate the solidification of the slurry 13, the tailings 11, and the polymer particles 14 to form a whole, but the polymer particles 14 have a pyrolysis temperature. When the pyrolysis temperature is exceeded, the molecular structure of the polymer particles 14 will be destroyed and collapse into a ball.

[0111] S34: Pull out the heating tube 10 to complete the curing of the permeable pile 4.

[0112] After solidification was completed, testing was carried out and the pile strength was 1.0MPa, which met the stability requirements of the tailings pond.

[0113] S4: Pile wall construction.

[0114] S41: According to the preset pile wall direction, the construction of the main body of the permeable piles 4 is completed continuously, and a certain overlap area must be ensured between adjacent permeable piles 4; the permeable piles 4 are engaged with each other to form a pile wall.

[0115] S42: After the main body construction of the second permeable pile 4 is completed, the first permeable pile 4 is heated and cured; after the main body construction of the third permeable pile 4 is completed, the second permeable pile 4 is heated and cured, and this sequence is repeated until all the permeable piles 4 are heated and cured.

[0116] Example 2

[0117] The difference from Example 1 is:

[0118] In S12, when the screw-in depth is 0-20 m, the particle size of the polymer particles 14 is 2 mm, the volume content of the polymer particles 14 is 6%, the volume content of the cement is 18%, the volume content of the water is 18%, and the volume content of the tailings 11 is 58%;

[0119] When the screwing depth is 20-40 m, the particle size of the polymer particles 14 is 1 mm, the volume content of the polymer particles 14 is 5%, the volume content of cement is 14%, the volume content of water is 14%, and the volume content of tailings 11 is 67%;

[0120] When the penetration depth is 40-60 m, the particle size of the high molecular polymer particles 14 is 0.5 mm, the volume content of the high molecular polymer particles 14 is 3%, the volume content of cement is 9%, the volume content of water is 9%, and the volume content of tailings 11 is 79%.

[0121] In S22, the curing temperature is 10°C.

[0122] In S32, after reaching the pyrolysis temperature, the temperature is maintained for (t+30) minutes.

[0123] In Example 2, the pile body strength after pile formation is 1.2 MPa.

[0124] Example 3

[0125] The difference from Example 1 is:

[0126] In S12, when the screwing depth is 0-20m, the particle size of the polymer particles 14 is 10mm, the volume content of the polymer particles 14 is 8%, the volume content of cement is 20%, the volume content of water is 22%, and the volume content of tailings 11 is 50%;

[0127] When the screwing depth is 20-40m, the particle size of the polymer particles 14 is 5mm, the volume content of the polymer particles 14 is 7%, the volume content of cement is 16%, the volume content of water is 18%, and the volume content of tailings 11 is 59%;

[0128] When the penetration depth is 40-60 m, the particle size of the high molecular polymer particles 14 is 2 mm, the volume content of the high molecular polymer particles 14 is 5%, the volume content of cement is 11%, the volume content of water is 13%, and the volume content of tailings 11 is 71%.

[0129] In S22, the curing temperature is 40°C.

[0130] In S32, after reaching the pyrolysis temperature, the temperature is maintained for (t+35) minutes.

[0131] In Example 3, the pile body strength after pile formation is 1.4 MPa.

[0132] Comparative Example 1

[0133] The difference from Example 1 is:

[0134] In S12, when the rotation depth is 0-20 m, the particle size of the polymer particles 14 is 0.5 mm, the volume content of the polymer particles 14 is 4%, the volume content of cement is 10%, the volume content of water is 10%, and the volume content of tailings 11 is 76%.

[0135] The particle size of the shallow polymer particles 14 is too small and the proportion is too low. The pore volume formed after the pile is formed is small, and it is not easy to form a continuous infiltration channel, which will lead to a low permeability of the pile body, and then increase the infiltration line of the tailings dam, affecting the stability of the dam body; the water and cement content is too low, the fluidity is weak, and it is not easy to fully bond the various component materials, resulting in a serious lack of pile strength.

[0136] Comparative Example 2

[0137] The difference from Example 1 is:

[0138] In S12, when the rotation depth is 20-40 m, the particle size of the polymer particles 14 is 0.2 mm, the volume content of the polymer particles 14 is 3%, the volume content of cement is 11%, the volume content of water is 11%, and the volume content of tailings is 75%.

[0139] The particle size of the middle polymer particles 14 is too small and the proportion is too low. After the pile is formed, the pore volume is small, and it is not easy to form a continuous infiltration channel, which will lead to a low permeability of the pile body, and then increase the infiltration line of the tailings dam, affecting the stability of the dam body; the water and cement content is too low, the fluidity is weak, and it is not easy to fully bond the various component materials, resulting in a serious lack of pile strength.

[0140] Comparative Example 3

[0141] The difference from Example 1 is:

[0142] In S12, when the rotation depth is 40-60 m, the particle size of the polymer particles 14 is 0.1 mm, the volume content of the polymer particles 14 is 1%, the volume content of cement is 6%, the volume content of water is 6%, and the volume content of tailings 11 is 87%.

[0143] The particle size of the deep polymer particles 14 is too small and the proportion is too low. The pore volume formed after the pile is formed is small, and it is not easy to form a continuous infiltration channel, which will lead to a low permeability of the pile body, and then increase the infiltration line of the tailings dam, affecting the stability of the dam body; the water and cement content is too low, the fluidity is weak, and it is not easy to fully bond the various component materials, resulting in a serious lack of pile strength.

[0144] Comparative Example 4

[0145] The difference from Example 1 is:

[0146] In S12, when the penetration depth is 0-20 m, the particle size of the polymer particles 14 is 13 mm, the volume content of the polymer particles 14 is 11%, the volume content of cement is 23%, the volume content of water is 25%, and the volume content of tailings 11 is 41%.

[0147] The particle size of the shallow polymer particles 14 is too large, and the pore volume formed after the pile is formed is large, and the continuity of the pile body is poor, which will cause the strength of the pile body to decrease significantly; if the water and cement content is too high, the pile forming time will be prolonged and the permeability of the nearby area will be reduced. In severe cases, it will cause the tailings dam infiltration line to rise, affecting the stability of the dam body.

[0148] Comparative Example 5

[0149] The difference from Example 1 is:

[0150] In S12, when the rotation depth is 20-40m, the particle size of the polymer particles 14 is 8mm, and the volume content of the polymer particles 14 is 10%. At this time, the volume content of cement is 19%, the volume content of water is 21%, and the volume content of tailings 11 is 50%.

[0151] The particle size of the middle polymer particles 14 is too large, and the pore volume formed after pile formation is large, and the continuity of the pile body is poor, which will cause the strength of the pile body to decrease significantly; if the water and cement content is too high, the pile formation time will be prolonged and the permeability of the nearby area will be reduced. In severe cases, it will cause the tailings dam infiltration line to rise, affecting the stability of the dam body.

[0152] Comparative Example 6

[0153] The difference from Example 1 is:

[0154] In S12, when the rotation depth is 40-60m, the particle size of the polymer particles 14 is preferably 5mm, and the volume content of the polymer particles 14 is 8%. At this time, the volume content of cement is 14%, the volume content of water is 16%, and the volume content of tailings 11 is 62%.

[0155] The particle size of the deep polymer particles 14 is too large, and the pore volume formed after pile formation is large, and the continuity of the pile body is poor, which will cause the strength of the pile body to decrease significantly; the water and cement content is high, which will extend the pile formation time and reduce the permeability of the nearby area. In severe cases, it will cause the tailings dam infiltration line to rise, affecting the stability of the dam body.

[0156] Comparative Example 7

[0157] The difference from Example 1 is:

[0158] In S22, the curing temperature is 5°C.

[0159] When the curing temperature is low, the hydration process of cement will slow down, affecting the early strength development of the permeable pile, thereby affecting the construction progress and the stability of the pile body.

[0160] Comparative Example 8

[0161] The difference from Example 1 is:

[0162] In S22, the curing temperature is 60°C.

[0163] When the curing temperature is high, the high temperature will accelerate the hydration process of the cement, causing the early strength of the permeable pile to develop too quickly, which will have an adverse effect on the stability of the pile body; high temperature in the early stage of curing will also lead to an increase in shrinkage cracks in the permeable pile, thereby affecting its durability and overall stability.

[0164] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0165] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A construction method for permeable interlocking piles for improving the stability of tailings ponds, characterized in that: The following steps are involved: S1: Carry out the main construction of the permeable pile (4); S2: heating and curing the permeable pile (4) obtained in S1; S3: reheating the water-permeable pile (4) obtained in S2 to form a water-permeable structure; S4: Continuously repeating the process of permeable pile (4) construction, permeable pile (4) heating and curing, and permeable pile (4) secondary heating to obtain a permeable interlocking pile wall; The S1 includes: S11: Construction preparation: a pressure sensor (3) is mounted on a drill pipe; a mixing head (1) is fixedly mounted on one end of the drill pipe, and a probe of the pressure sensor (3) is fixedly mounted inside the mixing head (1); the other end of the drill pipe is fixedly connected to a ground drive device and a control console (5); a channel is arranged inside the drill pipe, the channel passes through the mixing head (1), the end of the channel is a grouting hole (2), the head end of the channel is fixedly connected to a pumping device (6), the pumping device (6) is connected to a slurry barrel (7) through a pipeline, and the slurry barrel (7) is respectively connected to a collection barrel (8) and a liquid collection barrel (9) through pipelines; the control console (5) is respectively connected to the collection barrel (8), the liquid collection barrel (9), the pumping device (6), and the mixing head (1); cement, tailings (11), and high molecular polymer particles (14) are placed in the collection barrel (8), and water is placed in the liquid collection barrel (9); S12: before construction, calculating the contents of cement, water, high molecular polymer particles (14), and tailings (11) and obtaining high molecular polymer particles (14); S13: Construction begins. In the accumulation dam containing the tailings (11), the mixing head (1) is screwed into the tailings (11) according to the set position of the permeable pile (4); S14: the control console (5) adjusts the rotation speed of the mixing head (1), the power output of the ground driving device, and the descent rate of the drill pipe according to the descending resistance of the mixing head (1) fed back by the pressure sensor (3); S15: During the construction process, when the mixing head (1) is screwed into the tailings (11) to a predetermined depth, the control console (5) controls the switches of the aggregate bucket (8) and the liquid collection bucket (9), and adjusts the contents of cement, water, high molecular polymer particles (14), and tailings (11) according to the screwing depth and the volume content ratio of cement, water, high molecular polymer particles (14), and tailings (11) calculated in S12; cement and water form a slurry (13); cement, water, high molecular polymer particles (14), and tailings (11) form a mixture; S16: starting the pumping device (6), the pumping device (6) pumps the mixture into the grouting hole (2) at the bottom of the mixing head (1), and starts grouting. At the same time, the mixing head (1) starts stirring and slowly rises; S17: The mixing head (1) is gradually lifted until it leaves the surface of the tailings (11), completing the construction of the main body of the permeable pile (4).

2. The construction method of permeable interlocking piles for improving the stability of tailings pond according to claim 1, characterized in that: In the S12, The contents of cement, water, high molecular polymer particles (14) and tailings (11) are calculated according to the screw-in depth and the particle size of the tailings (11); the high molecular polymer is formed into a foam plastic sheet by a foam plastic thermoforming method, and then the high molecular polymer particles (14) having a particle size range identical to that of the tailings are obtained by cutting and particle size screening operations.

3. The construction method of permeable interlocking piles for improving the stability of tailings pond according to claim 1, characterized in that: In the S12, When the screwing depth of the stirring head (1) is 0 to 20 m, the particle size of the high molecular polymer particles (14) is: 2.0-10.0 mm, the volume content of the high molecular polymer particles (14) is 6-8%, at this time, the volume content of cement is: 18-20%, the volume content of water is: 18-22%, and the volume content of the tailings (11) is 50-58%; When the screw-in depth is 20 to 40 m, the particle size of the polymer particles (14) is: 1.0-5.0 mm, the volume content of the high molecular polymer particles (14) is 5-7%, at this time, the volume content of cement is: 14-16%, the volume content of water is: 14-18%, and the volume content of tailings (11) is 59-67%; When the screw-in depth is 40 to 60 m, the particle size of the polymer particles (14) is: 0.5-2.0 mm, the volume content of the high molecular polymer particles (14) is 3-5%, at this time, the volume content of cement is: 9-11%, the volume content of water is: 9-13%, and the volume content of tailings (11) is 71-79%.

4. The construction method of permeable interlocking piles for improving the stability of tailings pond according to claim 1, characterized in that: In the S16, The control console (5) controls the pumping pressure of the pumping device (6) according to the descending resistance of the stirring head (1) fed back by the pressure sensor (3).

5. The construction method of permeable interlocking piles for improving the stability of tailings pond according to claim 1, characterized in that: The S2 includes: S21: burying the electromagnetic cage (12) at a position centered on the central axis of the water-permeable pile (4), and pressing the electromagnetic cage (12) as a whole into the water-permeable pile (4); S22: A temperature probe is installed on the heating tube (10) and the heating tube (10) is pressed into the center of the permeable pile (4). The electromagnetic cage (12) is energized to increase the temperature of the heating tube (10) and accelerate the solidification of the pile body.

6. The construction method of permeable interlocking piles for improving the stability of tailings pond according to claim 5, characterized in that: In S21, The electromagnetic cage (12) is buried by vibration.

7. The construction method of permeable interlocking piles for improving the stability of tailings pond according to claim 5, characterized in that: In the step S22, the curing temperature, i.e. the heating temperature of the heating tube (10), is monitored, and the curing temperature is controlled to be 10-40°C by adjusting the current passing through the electromagnetic cage (12).

8. The construction method of permeable interlocking piles for improving the stability of tailings pond according to claim 1, characterized in that: The S3 includes: S31: raising the heating temperature of the heating tube (10) to a temperature higher than the thermal decomposition temperature of the high molecular weight polymer particles (14) to perform secondary heating; The heating time t required for the entire permeable pile (4) to reach the thermal decomposition temperature is calculated using the following formula: Among them, a is the thermal conductivity of the permeable pile, b is the heat capacity of the material, c is the ambient temperature, d is the radius of the permeable pile, e is the target temperature, and f is the initial temperature of the pile body; S32: The time required for the secondary heating process is (t+30) to (t+35) min; S33: After the time required for the secondary heating process is reached, the structure of the polymer particles (14) is destroyed and collapsed to form water-permeable pores; S34: Pull out the heating tube (10) to complete the secondary heating of the permeable pile (4).

9. The construction method of permeable interlocking piles for improving the stability of tailings pond according to claim 1, characterized in that: The S4 includes: S41: According to the preset pile wall direction, the construction of the main body of the permeable pile (4) is continuously completed; adjacent permeable piles (4) are interlocked with each other to form a pile wall; S42: After the main construction of the second permeable pile (4) is completed, the first permeable pile (4) is heated, solidified and reheated; after the main construction of the third permeable pile (4) is completed, the second permeable pile (4) is heated, solidified and reheated, and this sequence is repeated continuously until the heating, solidification and reheating of all the permeable piles (4) are completed.

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