Self-anchored anchor rod for reinforcing dangerous rock in hydro-fluctuation belt and rapid construction method

Abstract

The invention discloses a self-anchored anchor rod for reinforcing dangerous rock in a hydro-fluctuation belt and a rapid construction method, and relates to the technical field of rapid reinforcement of dangerous rock in the hydro-fluctuation belt in a reservoir area. The screw type anchor rod comprises a reusable anchor head, a screw type rod body and a fixed anchor head. According to the self-anchored anchor rod and the rapid construction method, self-locking anchoring and stress self-adaption are achieved by optimizing the structure of the anchor rod, and the anchoring reliability is remarkably improved; meanwhile, the rapid construction process is integrated with modular installation and a grouting-free technology, the construction period can be greatly shortened, and disturbance to the ecological environment of the hydro-fluctuation belt is reduced; the method not only solves the problems of low efficiency and poor durability of the traditional technology, but also provides an efficient and sustainable solution for dangerous rock reinforcement in a reservoir area high and steep bank slope and a dynamic water environment, and has important significance for improving the overall safety and ecological restoration capability of a reservoir.

Description

Technical Field

[0001] The invention relates to the technical field of rapid reinforcement of dangerous rock masses in a drawdown zone of a reservoir area, and in particular to a self-anchored anchor rod and a rapid construction method for reinforcing dangerous rocks in a drawdown zone. Background Art

[0002] As the water level in the reservoir area continues to change, the dangerous rocks in the drawdown zone of the reservoir area are exposed to the natural environment for a long time, and are subject to weathering, rain erosion and water scouring. They are prone to dangerous situations such as rock loosening, landslides or collapses, which seriously threaten the safety of the surrounding areas of the reservoir. As a transitional area for reservoir water level fluctuations, the stability of the rock mass in the drawdown zone is crucial to the safe operation of the reservoir area. Especially during the flood season or when the reservoir water level changes dramatically, if the dangerous rock reinforcement measures are not in place, it may lead to landslides, rock collapses, and even cause serious secondary disasters. Therefore, the reinforcement and protection of dangerous rocks in the drawdown zone is not only an important means to ensure the safety of life and property of the people in the reservoir area and the surrounding areas, but also a necessary measure to maintain the ecological environment of the reservoir area and reduce disaster risks.

[0003] Traditional reinforcement methods such as shotcrete and rock nail anchoring usually require a long construction period, especially under complex geological conditions, and the construction progress is often restricted by factors such as weather and terrain. This not only prolongs the overall construction time of the project, but may also increase the safety risks during the construction process, especially during the flood season or inclement weather conditions, where long construction periods may cause the project to stagnate and affect the reinforcement effect. At the same time, traditional reinforcement methods usually require a large amount of manpower and mechanical equipment, and the construction process is cumbersome and expensive. Especially for larger reservoir areas, long construction periods and high resource consumption make traditional reinforcement methods less economical. Therefore, when using traditional reinforcement methods, it is often necessary to invest a large amount of funds and materials, but the returns are not as expected, and the best cost-effectiveness cannot be achieved.

[0004] In general, traditional technologies have problems of low efficiency and poor durability;

[0005] In contrast, self-anchored anchor rods embed the ends of the anchor rods into the rock mass and achieve the transmission of anchoring force and reinforcement effect through self-anchored structural design, which has stronger adaptability and durability. Self-anchored anchor rods can effectively enhance the overall stability of the rock mass and reduce the impact caused by water level changes. In addition, combined with rapid construction methods, reinforcement work can be completed in a short time, which is especially suitable for the reinforcement of dangerous rocks in the drawdown zone of large-scale reservoirs. Rapid construction methods not only improve engineering efficiency, but also effectively reduce safety hazards caused by long construction periods. Therefore, the use of self-anchored anchor rods and their rapid construction methods can significantly improve the reinforcement effect of dangerous rocks in the drawdown zone of the reservoir area and ensure the safety of the reservoir area, which has important practical significance.

[0006] However, the existing self-anchoring anchor rods still need to be improved during use.

[0007] Therefore, a new solution to the above problems needs to be proposed. Summary of the invention

[0008] The purpose of the present invention is to provide a self-anchored anchor rod and a rapid construction method for reinforcing dangerous rocks in a drawdown zone, so as to solve the shortcomings of the current dangerous rock reinforcement method in a drawdown zone in a reservoir area and conventional self-anchored anchor rods, especially to solve the significant defects of the current dangerous rock reinforcement method in a drawdown zone in a reservoir area in terms of construction efficiency, terrain adaptability and long-term stability.

[0009] To achieve the above-mentioned object, the present invention provides the following technical solutions: a self-anchoring anchor rod for reinforcing dangerous rocks in a fall zone, comprising a reusable anchor head, an anchor rod and a fixed anchor head;

[0010] One end of the anchor rod is equipped with a reusable anchor head or a fixed anchor head according to the use requirements, and the other end of the anchor rod is fixedly connected with a drill bit;

[0011] Water outlets are provided on both sides of the drill bit, a guide tube body is arranged on the inner side of the anchor rod, the guide tube body is Y-shaped, the guide tube body is connected to the water outlet, a plurality of inlet holes are provided on the peripheral side of the guide tube body, a receiving groove is provided on both sides of the anchor rod, an anchor baffle is fixedly connected to the bottom end of the receiving groove, and an anchor tube body is fixedly connected to the inner side of the receiving groove.

[0012] Further, the reusable anchor head comprises a first anchor head shell, a water injection pipe, a control adjustment switch, an anchor filling control switch, an integrated box, a power output platform, an electric push rod, a piston, a sawtooth and a hydraulic booster;

[0013] A control and adjustment switch is provided on one side of the first anchor head shell away from one end of the anchor rod, an anchor filling control switch is provided on the other side of the first anchor head shell away from one end of the anchor rod, an integrated box is fixedly connected to one side of the outside of the first anchor head shell, a power output platform is fixedly connected to the inside of the first anchor head shell, a water injection pipe is fixedly connected to the center of the power output platform, one end of the water injection pipe is connected to a hydraulic booster, electric push rods are fixedly connected to both sides of the power output platform close to one end of the guide pipe body, a piston is fixedly connected to the other end of the electric push rod, a serration is provided at one end of the piston away from the electric push rod, and the piston is slidably connected to the inner side of the accommodating groove.

[0014] Furthermore, the wall thickness of the first anchor head shell is 0.5 cm, the material of the first anchor head shell is high-strength steel, and both sides of the first anchor head shell are designed to be raised, and the function of the raised parts on both sides is to facilitate the combination of the reusable anchor head with the drilling rig.

[0015] Furthermore, buckles are provided at the mounting position of the first anchor head shell, the mounting position of the water injection pipe, the mounting position of the guide pipe body and the mounting position of the anchor rod, and the connection between the first anchor head shell and the anchor rod and the connection between the water injection pipe and the guide pipe body are all assembled through buckles.

[0016] Furthermore, the integrated box includes a rechargeable battery, a water injection control integrated circuit and an anchor filling control integrated circuit. The control adjustment switch, the water injection control integrated circuit and the hydraulic booster are electrically connected. The anchor filling control switch, the anchor filling control integrated circuit and the electric push rod are electrically connected. The rechargeable battery is used to supply power to the remaining components.

[0017] Furthermore, the fixed anchor head comprises a second anchor head shell, a fastening bolt, an anchor replenishing bag, an anchor filling port and an anchor head isolation baffle. The end of the second anchor head shell away from the anchor rod is connected with the fastening bolt by a thread, the inner side of the second anchor head shell is provided with an anchor replenishing bag, the second anchor head shell is provided with second anchor head shells on both sides of the second anchor head shell close to one end of the anchor rod, the end of the second anchor head shell close to the anchor rod is fixedly connected with the anchor head isolation baffle, the anchor head isolation baffle is used to close the second anchor head shell, the end of the second anchor head shell close to the anchor rod is also provided with a buckle, the connection between the second anchor head shell and the anchor rod is assembled by the buckle, the end of the fastening bolt is also provided with serrations, and the serrations at the fastening bolt are used to pierce the anchor replenishing bag.

[0018] Furthermore, the inner sides of the anchor replenishing bag and the anchor tube are filled with a new water-resistant resin anchor, which is a mixture of an accelerator, montmorillonite and resin, and the accelerator includes but is not limited to NN dimethyl para-toluidine.

[0019] Furthermore, a wide thread is arranged around the outer side of the anchor rod, the width of the wide thread is 10 cm, and the thickness is 2 cm. The wide thread is used to reduce the resistance when drilling the anchor rod hole, thereby effectively shortening the reinforcement construction time.

[0020] Furthermore, the drill bit is a PDC drill bit.

[0021] A rapid construction method for a self-anchored anchor rod for reinforcing dangerous rocks in a falling zone comprises at least the following steps:

[0022] S1: First, connect the reusable anchor head to the anchor rod and the guide tube through the buckle, then connect the drilling rig to the protrusions on both sides of the reusable anchor head, and connect the water source at the water injection port. The preliminary work preparation is completed;

[0023] S2: Align the drill bit to the position that needs to be reinforced, start the drilling rig, and transmit the torque to the anchor rod through the reusable anchor head. The drill bit rotates at high speed under the action of the drilling rig. In order to avoid the drill bit temperature from being too high and reducing the drilling efficiency, start the control adjustment switch. Under the action of the hydraulic booster, the water source at the water injection port is collected to the hydraulic booster, and is pressurized inside the hydraulic booster to flow through the guide pipe and the water outlet and transmitted to the drill bit to cool the drill bit, and can reduce the friction between the drill bit and the rock mass to improve the drilling efficiency. Water injection is continuously performed during the entire drilling process;

[0024] S3: After reaching the drilling depth, shut down the drilling rig and separate it from the reusable anchor head, and cut off the water source at the water injection port. At this time, press the control adjustment switch again to control the hydraulic booster to generate suction in the opposite direction to the previous direction, so as to suck out the water in the borehole, the water in the diversion pipe, and the water that penetrates into the holding tank through the inlet hole, and discharge it through the water injection port. After the drainage is completed, press the control adjustment switch again to stop the hydraulic booster from working, so as to prepare for the next anchor filling;

[0025] S4: Anchor filling and reinforcement is performed. The anchor filling control switch is pressed, and the electric push rod gradually extends and pushes the piston to move toward the anchor pipe body. Gradually, the serrations on the piston pierce the anchor pipe body. Under the continuous compression of the piston driven by the electric push rod, the anchor pipe body flows into the guide pipe through the inlet hole. At this time, the control adjustment switch is pressed, and the hydraulic booster inhales air through the water injection port. The pressurized air pushes the new water-resistant resin anchor in the guide pipe into the water outlet until the borehole is filled. When the piston is pushed to the anchor baffle, it means that the new water-resistant resin anchor has been completely squeezed out. At this time, the anchor filling control switch is pressed again, and the electric push rod begins to retract until it reaches the starting state.

[0026] S5: After the anchoring agent is filled, in order to ensure that the new water-resistant resin anchoring agent can exert its water resistance and high strength to the greatest extent, the drilling rig is connected to the reusable anchor head again, and the anchor rod is rotated to stir the new water-resistant resin anchoring agent;

[0027] S6: After completing S, separate the reusable anchor head, separate the buckle between the reusable anchor head and the anchor rod, extract the reusable anchor head, and then install the fixed anchor head. After aligning the buckle on the fixed anchor head with the buckle on the rod body, the assembly is completed;

[0028] S7: Replenish the new water-resistant resin anchoring agent. In the process of extracting the reusable anchor head, it is inevitable that a small amount of the new water-resistant resin anchoring agent will be carried out. In order to avoid the problem of insufficient filling of the new water-resistant resin anchoring agent, which will lead to reduced overall waterproofness and strength, an anchoring agent replenishing bag is also provided inside the fixed anchor head. The anchoring agent replenishing bag is punctured under the push of the fastening bolt, and the new water-resistant resin anchoring agent in the anchoring agent replenishing bag flows out through the anchoring agent filling port and fills the drill hole to achieve maximum airtightness and waterproofness.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. Fast construction speed and time saving: The present invention adopts self-anchored anchor rods and fast construction methods, which can greatly shorten the construction period. Compared with traditional reinforcement methods, the reinforcement method using self-anchored anchor rods can complete the installation and reinforcement work more quickly, reduce the time waste in the construction process, and improve the overall efficiency of the project. It is particularly suitable for areas with high requirements for construction period such as the drawdown zone of the reservoir area;

[0031] 2. Long-lasting reinforcement effect and high reliability: The anchoring structure of the proposed self-anchored anchor rod can penetrate deep into the rock mass and stabilize the anchoring force through the rotating rising wide thread. Under the protection of the new waterproof anchoring agent, it will not be affected by water erosion or weathering, and can maintain stability and reinforcement effect for a long time, avoiding the gradual degradation problem that may occur in traditional methods;

[0032] 3. Improve safety and reduce construction risks: The construction process of self-anchored anchors is relatively simple and efficient, and does not require excessive manual operation and complex equipment configuration, thus reducing risks and safety hazards at the construction site. Especially in high-risk areas, rapid construction can reduce the time that personnel stay on site, thereby reducing the chance of accidents;

[0033] 4. Environmentally friendly and reduces pollution: Compared with traditional reinforcement methods, the self-anchored anchor rod and rapid construction method of the present invention have less impact on the environment during construction. Traditional methods often require a large amount of concrete spraying and mechanical operation, which may cause dust pollution. However, during the construction of the self-anchored anchor rod, a large amount of waste is not generated, and the construction process is more environmentally friendly, which helps to reduce the negative impact on the ecological environment;

[0034] 5. Superior economical efficiency: Compared with traditional reinforcement methods, the cost of self-anchored anchor rods and rapid construction methods is more economical. Due to the shortened construction period, reduced labor and equipment investment, the total cost of the entire reinforcement process is relatively low, with a high cost-effectiveness, which can save a lot of money for the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0036] Figure 1 It is a cross-sectional schematic diagram of the self-anchoring anchor rod of the present invention;

[0037] Figure 2 It is a schematic diagram of the reusable anchor head of the present invention;

[0038] Figure 3 It is a schematic diagram of the anchor rod of the present invention;

[0039] Figure 4 This is a schematic diagram of the self-anchoring anchor rod after the fixed anchor head is replaced according to the present invention.

[0040] In the figure: 101, water injection pipe; 102, control adjustment switch; 103, anchor filling control switch; 104, integrated box; 105, power output platform; 106, electric push rod; 107, piston; 108, sawtooth; 109, hydraulic booster; 110, buckle; 201, guide tube; 202, anchor pipe body; 203, wide thread; 204, anchor baffle; 205, water outlet; 206, drill bit; 301, fastening bolt; 302, anchor replenishing bag; 303, anchor filling port; 304, anchor head isolation baffle. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0042] Embodiment 1:

[0043] A self-anchored anchor rod for reinforcing dangerous rocks in a fall zone, comprising a reusable anchor head, an anchor rod and a fixed anchor head;

[0044] See also Figure 3 One end of the anchor rod is equipped with a reusable anchor head or a fixed anchor head according to the use requirements, and the other end of the anchor rod is fixedly connected with a drill bit 206;

[0045] Water outlets 205 are provided on both sides of the drill bit 206, and a guide tube body 201 is arranged on the inner side of the anchor rod. The guide tube body 201 is Y-shaped and connected to the water outlet 205. A plurality of inlet holes are provided on the peripheral side of the guide tube body 201. Receiving grooves are provided on both sides of the anchor rod, and an anchor baffle 204 is fixedly connected to the bottom end of the receiving groove, and an anchor tube body 202 is fixedly connected to the inner side of the receiving groove.

[0046] See also Figure 1 The reusable anchor head includes a first anchor head shell, a water injection pipe 101, a control adjustment switch 102, an anchor filling control switch 103, an integrated box 104, a power output platform 105, an electric push rod 106, a piston 107, a sawtooth 108 and a hydraulic booster 109;

[0047] See also Figure 2 A control and adjustment switch 102 is provided on one side of the first anchor head shell away from one end of the anchor rod, and an anchor filling control switch 103 is provided on the other side of the first anchor head shell away from one end of the anchor rod. An integrated box 104 is fixedly connected to one side of the outside of the first anchor head shell, and a power output platform 105 is fixedly connected to the inside of the first anchor head shell. A water injection pipe 101 is fixedly connected to the center of the power output platform 105, and a hydraulic booster 109 is connected to one end of the water injection pipe 101. Electric push rods 106 are fixedly connected to both sides of the power output platform 105 near one end of the guide pipe body 201, and a piston 107 is fixedly connected to the other end of the electric push rod 106. A sawtooth 108 is provided at the end of the piston 107 away from the electric push rod 106, and the piston 107 is slidably connected to the inner side of the accommodating groove.

[0048] The wall thickness of the first anchor head shell is 0.5 cm, in order to increase the stability and durability of the anchor head under the strong torque of the drilling rig. The material of the first anchor head shell is high-strength steel. The two sides of the first anchor head shell are designed with bulges. The function of the bulges on both sides is to facilitate the combination of the reusable anchor head and the drilling rig. The reusable anchor head is connected to the drilling rig, and the rotating drilling rig enables the reusable anchor head to drive the anchor rod to rotate at high speed, thereby realizing the excavation of the borehole. Since the reusable anchor head is directly connected to the drilling rig, the anchor head itself will bear a large torque. In order to increase the safety, stability and durability of the anchor head, the outer wall of the reusable anchor head proposed in the present invention is made of thickened high-strength steel.

[0049] Buckles 110 are provided at the mounting positions of the first anchor head shell, the water injection pipe 101 , the flow guide pipe body 201 and the anchor rod. The connection between the first anchor head shell and the anchor rod and the connection between the water injection pipe 101 and the flow guide pipe body 201 are all assembled through the buckles 110 .

[0050] The integrated box 104 includes a rechargeable battery, a water injection control integrated circuit and an anchor filling control integrated circuit. The control adjustment switch 102, the water injection control integrated circuit and the hydraulic booster 109 are electrically connected. The anchor filling control switch 103, the anchor filling control integrated circuit and the electric push rod 106 are electrically connected. The rechargeable battery is used to supply power to the remaining components.

[0051] See also Figure 4 The fixed anchor head includes a second anchor head shell, a fastening bolt 301, an anchor replenishing bag 302, an anchor filling port 303 and an anchor head isolation baffle 304. The end of the second anchor head shell away from the anchor rod is connected with the fastening bolt 301 by a thread, the inner side of the second anchor head shell is provided with an anchor replenishing bag 302, and the second anchor head shell is provided on both sides of the second anchor head shell close to the anchor rod. The end of the second anchor head shell close to the anchor rod is fixedly connected with the anchor head isolation baffle 304, and the anchor head isolation baffle 304 is used to close the second anchor head shell. The end of the second anchor head shell close to the anchor rod is also provided with a buckle 110, and the connection between the second anchor head shell and the anchor rod is assembled through the buckle 110. The end of the fastening bolt 301 is also provided with a serration 108, and the serration 108 at the fastening bolt 301 is used to pierce the anchor replenishing bag 302.

[0052] The buckle 110 in different embodiments may be electrically controlled. When the buckle 110 is electrically controlled, it is moved, connected and separated by power control. When the buckle 110 is electrically controlled, a corresponding control integrated circuit needs to be added to the integrated box 104, and it needs to be connected to a rechargeable battery.

[0053] In different embodiments, a normal toggle buckle may also be selected;

[0054] The four buckles 110 of the reusable anchor head are respectively connected to the anchor rod and the guide tube 201. Before replacing the fixed anchor head, the buckles 110 at the connection between the reusable anchor head and the anchor rod and the buckles 110 at the connection between the reusable anchor head and the guide tube 201 are separated, and the buckles 110 on the reusable anchor head and the rod body are separated.

[0055] Then, the connection between the fixed anchor head and the anchor rod can be carried out. When the buckle 110 of the fixed anchor head and the buckle 110 of the anchor rod are in contact and buckled together, the fixed anchor head and the anchor rod are assembled and fixed.

[0056] The inner sides of the anchor replenishing bag 302 and the anchor tube body 202 are filled with a new water-resistant resin anchor. The new water-resistant resin anchor is an anchor mixed with an accelerator, montmorillonite and resin. The accelerator includes but is not limited to NN dimethyl paratoluidine. Compared with the traditional resin anchor, its stability, mechanical properties and water resistance are significantly improved. The setting time of the improved resin anchor is shortened by 55.8%, the uniaxial compressive strength is increased by 28.5%, the tensile strength is increased by 25.4%, and the water resistance is increased by 14.8%. The curing agent reacts with the accelerator and the resin oil to generate more three-dimensional network structures. The addition of montmorillonite powder improves the density and water resistance of the material. The anchor has a large tensile strength, strong water resistance, and less damage during pulling. In addition, the new water-resistant anchor has strong water resistance and still has a good curing effect in a water-rich environment. The mechanical properties of water-resistant anchoring agents are relatively stable. In a water-rich environment, the anchoring force will not be seriously reduced due to moisture and can maintain its effectiveness for a long time, ensuring long-term stability and safety after construction. In terms of durability, due to its excellent water resistance and mechanical properties, it has significant long-term use effects in harsh environments;

[0057] After the anchor filling is completed, the reusable anchor head is replaced with a fixed anchor head with a lower cost. After the anchor head is replaced, the anchor filling at the hole opening of the drill hole is insufficient, so an anchor supplement bag 302 is provided inside the fixed anchor head to achieve sufficient filling of the entire drill hole. Saw teeth are provided at the front end of the fastening bolt. When the fastening bolt is rotated to tighten the anchor rod, the front end serrations 108 pierce the anchor, and the anchor flows out from the anchor filling port 303 in the fixed anchor head to achieve filling at the hole opening. An anchor head isolation baffle 304 is provided in the fixed anchor head to prevent the anchor from flowing into the anchor rod, resulting in insufficient anchor filling.

[0058] The reusable anchor head can be connected and separated from the anchor rod. The reusable anchor head with a higher cost can be reused. After the drilling reinforcement is completed, the reusable anchor head is separated from the anchor rod, and the conventional anchor head is used to connect the anchor rod, and the fixed anchor head is tightened by tightening bolts to achieve the purpose of plugging the drilling hole.

[0059] The outer side of the anchor rod is surrounded by a wide thread 203, which is 10 cm wide and 2 cm thick. The wide thread 203 is used to reduce the resistance when drilling the anchor rod hole, effectively shortening the reinforcement construction time; when the anchor rod is rotated, the wide thread 203 can effectively clean the loose materials on the anchor hole wall, ensuring better contact and friction between the anchor rod and the hole wall. This helps to enhance the anchoring effect, improve the transmission efficiency of the anchoring force, and effectively reduce the anchoring failure caused by impurities. At the same time, the longer thread design increases the contact area between the anchor rod and the rock mass. The friction and adhesion between the anchor rod and the rock mass are stronger, thereby improving the anchoring effect. The larger contact area can disperse external forces, reduce stress concentration, and enable the anchor rod to provide more stable support in the entire reinforcement system. The spiral rising thread design can roll out rock cuttings and soil from the borehole while drilling with the anchor rod, which greatly saves the time of cleaning the anchor rod hole and provides a good service environment for subsequent anchor reinforcement. The rotation of the thread can fully stir the anchor tube 202 to maximize its strength.

[0060] Drill bit 206 is a PDC drill bit, Polycrystalline Diamond Compact. Compared with traditional metal or alloy drill bits, PDC drill bits have the advantages of good wear resistance and high hardness. They can maintain sharp cutting ability for a longer time, reduce frequent replacement due to wear, and improve drilling efficiency.

[0061] Embodiment 2:

[0062] Based on the first embodiment, this embodiment proposes a rapid construction method of a self-anchored anchor rod for reinforcing dangerous rocks in a fall zone, which at least includes the following steps:

[0063] S1: First, the reusable anchor head is connected to the anchor rod and the guide tube 201 respectively through the buckle 110, and then the drilling rig is connected to the protrusions on both sides of the reusable anchor head, and the water source is connected at the water injection port 101. The preliminary work preparation is completed;

[0064] S2: Align the drill bit 206 to the position that needs to be reinforced, start the drilling rig, and transmit the torque to the anchor rod through the reusable anchor head. The drill bit 206 rotates at a high speed under the action of the drilling rig. In order to prevent the drill bit 206 from overheating and reducing the drilling efficiency, start the control adjustment switch 102. Under the action of the hydraulic booster 109, the water source at the water injection port 101 is collected to the hydraulic booster 109, and is pressurized inside the hydraulic booster 109 to flow through the guide pipe 201 and the water outlet 205 to be transmitted to the drill bit 206, thereby cooling the drill bit 206, and reducing the friction between the drill bit 206 and the rock mass to improve the drilling efficiency. Water injection is continuously performed during the entire drilling process;

[0065] In order to improve the drilling efficiency of the drill bit 206, the optimal parameters are calculated according to the following formula. The mechanical calculation formula of the PDC drill bit 206 is as follows. The geometric relationship between the PDC drill bit 206 and the elastic half-space body of the rock at the bottom of the hole can be used to calculate two stresses p1 and p2 respectively. Then p1 and p2 are:

[0066]

[0067] Wherein, v is the Poisson's ratio of the rock at the bottom of the hole; a is the contact area between the drill bit 206 and the rock; E is the elastic modulus of the rock at the bottom of the hole; and R is the radius of the PDC.

[0068] According to the definition of contact stiffness, the simplified contact pressure F of PDC drill bit 206 can be obtained: N2 The calculation formula is:

[0069]

[0070] Wherein, β is a constant, which is determined by the shape of the contact surface, and the circular cross section is 0.5; A is the contact area of ​​the cylinder; d' is the average depth of the front end surface of the drill bit 206, d'=l / 2; c is the contact stiffness of the cylindrical surface;

[0071] Similarly, according to the analysis results of the cylindrical flat bottom contact theory, the contact stress P of the contact surface can be obtained after simplified calculation: N for:

[0072]

[0073] Friction force F between the bottom of the PDC cutter and the rock s for:

[0074] F s =f·F N

[0075] According to the force balance principle, the tangential force F t for:

[0076]

[0077] Where S is the horizontal tangential displacement; f is the rock sliding friction coefficient.

[0078] During the drilling process, the spiral rising wide thread 203 design on the outside of the rod body can promptly roll out the rock debris and soil in the borehole. At the same time, the spiral design can also effectively clean the loose materials on the anchor hole wall, which not only greatly saves the time for cleaning the borehole, but also makes the friction and adhesion between the anchor rod and the rock stronger, thereby improving the anchoring effect.

[0079] S3: After reaching the drilling depth, the drilling rig is turned off and separated from the reusable anchor head, and the water source at the water injection port 101 is cut off. At this time, the control adjustment switch 102 is pressed again to control the hydraulic booster 109 to generate suction in the opposite direction to the previous direction, so as to suck out the water in the borehole, the water in the guide pipe 201, and the water that penetrates into the receiving tank through the inlet hole, and discharge it through the water injection port 101. After the drainage is completed, the control adjustment switch 102 is pressed again to stop the hydraulic booster 109 from working, so as to prepare for the subsequent anchor filling;

[0080] S4: Anchor filling and reinforcement is performed. The anchor filling control switch 103 is pressed, and the electric push rod 106 gradually extends and pushes the piston 107 to move toward the anchor tube 202. Gradually, the serrations 108 on the piston 107 pierce the anchor tube 202. Under the continuous compression of the piston 107 driven by the electric push rod 106, the anchor tube 202 flows into the guide tube 201 through the inlet hole. At this time, the control adjustment switch 102 is pressed, and the hydraulic booster 109 inhales air through the water injection port 101. The pressurized air pushes the new water-resistant resin anchor in the guide tube 201 to flow into the water outlet 205 until the borehole is filled. When the piston 107 is pushed to the anchor baffle 204, it means that the new water-resistant resin anchor has been completely squeezed out. At this time, the anchor filling control switch 103 is pressed again, and the electric push rod 106 begins to recover until it reaches the starting state.

[0081] S5: After the anchoring agent is filled, in order to ensure that the new water-resistant resin anchoring agent can exert its water resistance and high strength to the greatest extent, the drilling rig is connected to the reusable anchor head again, and the anchor rod is rotated to stir the new water-resistant resin anchoring agent;

[0082] The torsion and thrust of the drilling rig can be calculated by the following formula. According to the principle of force balance between the anchor rod and the anchoring agent, the force of the anchor rod during the initial stirring of the anchoring agent can be obtained:

[0083] F1=F b cos(γ+λ)+F b sin(γ+λ)

[0084] F2=F b sin(γ+λ)-F b cos(γ+λ)

[0085] Where, F1 is the torsional force of the drilling rig; F2 is the thrust of the drilling rig; F b is the positive pressure on the stirring end surface; γ is the cutting angle of the stirring end; λ is the angle between the plane perpendicular to the cutting surface of the anchor stirring end and the horizontal direction.

[0086] When the spatial parameters of the bolt stirring end and the properties of the anchoring agent are determined, the relationship between F1 and F2 is finally established by combining the expressions of F1 and F2:

[0087]

[0088] Wherein, δ = arctan(n, n is a parameter related to the properties of the anchoring agent.

[0089] S6: After completing S5, separate the reusable anchor head, separate the buckle 110 between the reusable anchor head and the anchor rod, extract the reusable anchor head, and then install the fixed anchor head. Align the buckle 110 on the fixed anchor head with the buckle 110 on the rod body to complete the assembly;

[0090] S7: Replenish the new water-resistant resin anchoring agent. In the process of extracting the reusable anchor head, a small amount of the new water-resistant resin anchoring agent will inevitably be carried out. In order to avoid the problem of insufficient filling of the new water-resistant resin anchoring agent resulting in reduced overall waterproofness and strength, an anchoring agent replenishing bag 302 is also provided inside the fixed anchor head. When the fastening bolt 301 pushes, the solid agent replenishing bag 302 is punctured, and the new water-resistant resin anchoring agent in the solid agent replenishing bag 302 flows out through the anchoring agent filling port 303 to fill the drill hole to achieve maximum airtightness and waterproofness.

[0091] In summary:

[0092] The self-anchoring anchor rod and rapid construction method of the present invention realize self-locking anchoring and stress adaptation by optimizing the anchor rod structure, thereby significantly improving the anchoring reliability; at the same time, the rapid construction process integrates modular installation and grouting-free technology, which can greatly shorten the construction period and reduce the disturbance to the ecological environment of the drawdown zone; this method not only solves the problems of low efficiency and poor durability of traditional technologies, but also provides an efficient and sustainable solution for the reinforcement of dangerous rocks under high and steep slopes and dynamic water environments in reservoir areas, which is of great significance to improving the overall safety of reservoirs and the ecological restoration capacity, that is, it can achieve efficient, economical, environmentally friendly and reliable reinforcement effects for dangerous rocks in the drawdown zone, overcomes the shortcomings of traditional reinforcement methods under periodic changes in reservoir water levels, and has significant technical advantages and practical application value.

[0093] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A self-anchored anchor rod for reinforcing dangerous rocks in a falling zone, characterized in that: Including reusable anchor heads, anchor rods and fixed anchor heads; One end of the anchor rod is equipped with a reusable anchor head or a fixed anchor head according to usage requirements, and the other end of the anchor rod is fixedly connected to a drill bit (206); Water outlets (205) are provided on both sides of the drill bit (206); a flow guide pipe body (201) is provided on the inner side of the anchor rod; the flow guide pipe body (201) is Y-shaped and connected to the water outlet (205); a plurality of inlet holes are provided on the peripheral side of the flow guide pipe body (201); a receiving groove is provided on both sides of the anchor rod; an anchor baffle (204) is fixedly connected to the bottom end of the receiving groove; and an anchor pipe body (202) is fixedly connected to the inner side of the receiving groove.

2. The self-anchored anchor rod for reinforcing dangerous rocks in a falling zone according to claim 1, characterized in that: The reusable anchor head comprises a first anchor head shell, a water injection pipe (101), a control adjustment switch (102), an anchor filling control switch (103), an integrated box (104), a power output platform (105), an electric push rod (106), a piston (107), a sawtooth (108) and a hydraulic booster (109); A control and adjustment switch (102) is provided on one side of the first anchor head shell away from one end of the anchor rod, and an anchor filling control switch (103) is provided on the other side of the first anchor head shell away from one end of the anchor rod. An integrated box (104) is fixedly connected to one side of the outside of the first anchor head shell, and a power output platform (105) is fixedly connected to the inside of the first anchor head shell. A water injection pipe (101) is fixedly connected to the center of the power output platform (105), and one end of the water injection pipe (101) is connected to a hydraulic booster (109). Both sides of the power output platform (105) close to one end of the guide pipe body (201) are fixedly connected to electric push rods (106), and the other end of the electric push rod (106) is fixedly connected to a piston (107). A sawtooth (108) is provided at one end of the piston (107) away from the electric push rod (106), and the piston (107) is slidably connected to the inner side of the accommodating groove.

3. The self-anchored anchor rod for reinforcing dangerous rocks in a falling zone according to claim 2 is characterized in that: The wall thickness of the first anchor head shell is 0.5 cm. The material of the first anchor head shell is high-strength steel. Both sides of the first anchor head shell are designed with protrusions. The function of the protrusions on both sides is to facilitate the combination of the reusable anchor head with the drilling rig.

4. The self-anchored anchor rod for reinforcing dangerous rocks in a falling zone according to claim 2, characterized in that: Buckles (110) are provided at the mounting position of the first anchor head shell, the mounting position of the water injection pipe (101), the mounting position of the flow guide pipe body (201) and the mounting position of the anchor rod. The connection between the first anchor head shell and the anchor rod and the connection between the water injection pipe (101) and the flow guide pipe body (201) are all assembled via the buckles (110).

5. The self-anchored anchor rod for reinforcing dangerous rocks in a falling zone according to claim 2, characterized in that: The integrated box (104) comprises a rechargeable battery, a water injection control integrated circuit and an anchor filling control integrated circuit; the control adjustment switch (102), the water injection control integrated circuit and the hydraulic booster (109) are electrically connected; the anchor filling control switch (103), the anchor filling control integrated circuit and the electric push rod (106) are electrically connected.

6. The self-anchored anchor rod for reinforcing dangerous rocks in a falling zone according to claim 4, characterized in that: The fixed anchor head comprises a second anchor head shell, a fastening bolt (301), an anchor replenishing bag (302), an anchor filling port (303) and an anchor head isolation baffle (304); the end of the second anchor head shell away from the anchor rod is connected to the fastening bolt (301) by threading; the inner side of the second anchor head shell is provided with an anchor replenishing bag (302); the second anchor head shell is provided on both sides of the second anchor head shell close to the anchor rod; the end of the second anchor head shell close to the anchor rod is fixedly connected to the anchor head isolation baffle (304); the anchor head isolation baffle (304) is used to close the second anchor head shell; the end of the second anchor head shell close to the anchor rod is also provided with a buckle (110); the connection between the second anchor head shell and the anchor rod is assembled by the buckle (110); the end of the fastening bolt (301) is also provided with a serration (108); the serration (108) at the fastening bolt (301) is used to pierce the anchor replenishing bag (302).

7. The self-anchored anchor rod for reinforcing dangerous rocks in a falling zone according to claim 6, characterized in that: The inner sides of the anchor replenishing bag (302) and the anchor tube (202) are filled with a new water-resistant resin anchor, which is a mixture of an accelerator, montmorillonite and resin. The accelerator includes but is not limited to NN dimethyl paratoluidine.

8. The self-anchored anchor rod for reinforcing dangerous rocks in a falling zone according to claim 1, characterized in that: A wide thread (203) is arranged around the outer side of the anchor rod. The wide thread (203) has a width of 10 cm and a thickness of 2 cm. The wide thread (203) is used to reduce the resistance when drilling the anchor rod hole, effectively shortening the reinforcement construction time.

9. The self-anchored anchor rod for reinforcing dangerous rocks in a falling zone according to claim 1, characterized in that: The drill bit (206) is a PDC drill bit.

10. A rapid construction method for a self-anchored anchor rod for reinforcing dangerous rocks in a drawdown zone, used for a self-anchored anchor rod for reinforcing dangerous rocks in a drawdown zone as claimed in any one of claims 1 to 9, characterized in that: At least the following steps are included: S1: First, the reusable anchor head is connected to the anchor rod and the guide tube (201) respectively through the buckle (110), then the drilling rig is connected to the protrusions on both sides of the reusable anchor head, and the water source is connected at the water injection port (101), and the preliminary work preparation is completed; S2: Align the drill bit (206) with the position to be reinforced, start the drilling rig, and transmit the torque to the anchor rod through the reusable anchor head. The drill bit (206) rotates at a high speed under the action of the drilling rig. In order to prevent the drill bit (206) from overheating and reducing the drilling efficiency, the control adjustment switch (102) is started. Under the action of the hydraulic booster (109), the water source at the water injection port (101) is collected to the hydraulic booster (109), and is pressurized inside the hydraulic booster (109) and flows through the guide pipe (201) and the water outlet (205) to be transmitted to the drill bit (206), thereby achieving cooling of the drill bit (206), and reducing the friction between the drill bit (206) and the rock mass to improve the drilling efficiency. Water injection is continuously performed during the entire drilling process; S3: After reaching the drilling depth, the drilling machine is turned off and separated from the reusable anchor head, and the water source at the water injection port (101) is cut off. At this time, the control adjustment switch (102) is pressed again to control the hydraulic booster (109) to generate suction in the opposite direction to the previous direction, so as to suck out the water in the borehole, the water in the guide pipe (201), and the water that penetrates into the receiving tank through the inlet hole, and discharge it through the water injection port (101). After the drainage is completed, the control adjustment switch (102) is pressed again to stop the hydraulic booster (109) from working, so as to prepare for the subsequent anchor filling; S4: Anchor filling and reinforcement is performed. The anchor filling control switch (103) is pressed, and the electric push rod (106) gradually extends and pushes the piston (107) to move toward the anchor tube (202). Gradually, the saw teeth (108) on the piston (107) pierce the anchor tube (202). Under the continuous compression of the piston (107) driven by the electric push rod (106), the anchor tube (202) flows into the guide tube (201) through the inlet hole. At this time, the control adjustment switch is pressed. The hydraulic booster (109) of the switch (102) sucks air through the water injection port (101), and the pressurized air pushes the new water-resistant resin anchoring agent in the guide tube (201) to flow into the water outlet (205) until the borehole is filled. When the piston (107) is pushed to the anchoring agent baffle (204), it means that the new water-resistant resin anchoring agent has been completely squeezed out. At this time, the anchoring agent filling control switch (103) is pressed again, and the electric push rod (106) starts to recover until the starting state; S5: After the anchoring agent is filled, in order to ensure that the new water-resistant resin anchoring agent can exert its water resistance and high strength to the greatest extent, the drilling rig is connected to the reusable anchor head again, and the anchor rod is rotated to stir the new water-resistant resin anchoring agent; S6: After completing S5, the reusable anchor head is separated, the buckle (110) between the reusable anchor head and the anchor rod is separated, the reusable anchor head is extracted, and then the fixed anchor head is installed, and the buckle (110) on the fixed anchor head is aligned with the buckle (110) on the rod body to complete the assembly; S7: Replenishing the new water-resistant resin anchoring agent. In the process of extracting the reusable anchor head, a small amount of the new water-resistant resin anchoring agent will inevitably be carried out. In order to avoid the problem of insufficient filling of the new water-resistant resin anchoring agent leading to reduced overall waterproofness and strength, an anchoring agent replenishing bag (302) is also provided inside the fixed anchor head. When the fastening bolt (301) pushes forward, the solidifying agent replenishing bag (302) is punctured, and the new water-resistant resin anchoring agent in the solidifying agent replenishing bag (302) flows out through the anchoring agent filling port (303) and fills the drill hole to achieve maximum airtightness and waterproofness.

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