A device for removing steel from a diaphragm wall and a method of implementing the same

Abstract

The application provides a type steel removing device for underground continuous wall and an implementation method, wherein the device comprises a drilling assembly, a hydraulic circulating drilling machine system and a mud circulating system; the drilling assembly comprises a drill bit, an inner cutting edge pipe and an outer cutting edge pipe which are sequentially nested outside the drill bit and can rotate synchronously with the drill bit, and the drill rod has an inner cavity for supplying mud to the drill bit; a cavity for mud backflow is formed between the drill bit and the outer cutting edge pipe by axially separating the inner cutting edge pipe from the outer cutting edge pipe; an electromagnetic pipe is fixedly sleeved outside the drill rod, and the electromagnetic pipe is magnetized by power supply to form a gradient magnetic field in the cavity to adsorb the type steel debris carried in the backflow mud. The device of the application integrates the construction steps of drilling, hole cleaning, wall protection and type steel removing into one by virtue of the composite design of the electromagnetic pipe, thereby greatly reducing the steps of frequently replacing mechanical equipment in the construction process.

Description

Technical Field

[0001] This invention relates to the field of urban underground space research technology, specifically to a steel section removal device and implementation method for underground continuous walls. Background Technology

[0002] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art.

[0003] With rapid urban development and the continuous utilization of underground space, adding new subway lines to existing subway tunnels has become a common solution to alleviate increasing urban traffic pressure. This frequently leads to intersections between existing subway tunnels and newly constructed subway lines, creating construction challenges related to the diaphragm walls where new lines pass under existing stations. The strength of the diaphragm wall mainly consists of two parts: the reinforced concrete wall and the embedded steel joints. Common methods for clearing diaphragm walls include manual clearing, mechanical clearing, or direct cutting with a tunnel boring machine. Regardless of the method used, the steel joints embedded in the diaphragm wall have a higher hardness than the surrounding structure, making them a key and difficult part of the clearing process.

[0004] Based on this, the design background of the present invention adopts the approach of first removing the internal steel of the diaphragm wall, and then removing the remaining part of the diaphragm wall.

[0005] Traditionally, steel section removal equipment at construction sites primarily uses rotary drilling rigs, which directly excavate from the ground until the entire steel section is ground away. However, using conventional rotary drilling rigs can lead to several problems, such as cumbersome construction procedures (requiring drilling and cleaning the ground before changing the drill bit for diaphragm wall removal), slow construction efficiency, and the fact that metal shavings generated during steel cutting tend to adhere to the drill bit, greatly increasing drill bit wear, reducing cutting efficiency, and being difficult to remove.

[0006] Therefore, this invention proposes a steel section removal device and implementation method for diaphragm walls. The main objective is to improve the efficiency of obstacle removal while simplifying the construction steps, enabling a single device to complete the entire steel section removal process for diaphragm walls. Summary of the Invention

[0007] This invention aims to solve a series of problems caused by the removal of steel sections inside the diaphragm wall of existing stations. Based on achieving the most efficient removal of steel sections in the diaphragm wall and reducing construction steps, this invention proposes a steel section removal device and implementation method for underground diaphragm walls.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows: a steel section removal device for underground continuous wall, comprising a drilling assembly, the drilling assembly comprising a drill bit, an inner cutting edge tube and an outer cutting edge tube that can rotate synchronously with the drill bit are nested in sequence on the outside of the drill bit, and a drill rod that drives the drill bit to rotate is provided on the top of the drill bit. The drill pipe has an internal cavity for conveying mud to the drill bit; By axially pulling the inner cutter tube away from the outer cutter tube, a cavity is formed between the drill bit and the outer cutter tube for mud return. An electromagnetic tube is fixedly fitted on the outside of the drill pipe. When energized, the electromagnetic tube is magnetized to form a gradient magnetic field in the cavity, which adsorbs steel debris carried in the return mud. The steel section removal device also includes a hydraulic circulating drilling system and a mud circulation system; The hydraulic circulating drilling system is used to pull the drilling rig components from the ground to the corresponding diaphragm wall steel. The mud circulation system is used to deliver mud to the drill pipe cavity and to pump and recover the mud in the cavity to form a mud circulation.

[0009] Furthermore, the front end of the outer cutting edge tube protrudes beyond the front end of the inner cutting edge tube, and the front end of the inner cutting edge tube protrudes beyond the front end of the drill bit. Both the front ends of the outer and inner cutting edge tubes have annular serrated structures.

[0010] Furthermore, the outer peripheral sidewall of the outer cutting edge tube has a corrugated tube structure, which is used to support the outer cutting edge tube in the drill hole.

[0011] Furthermore, both the inner side of the outer blade tube and the outer side of the drill bit are provided with axially extending connecting blocks, and both the outer and inner sides of the inner blade tube are provided with axially extending connecting grooves that are inserted and matched with the corresponding connecting blocks. The drill bit, inner cutting edge tube, and outer cutting edge tube are kept rotating synchronously through corresponding connecting blocks and connecting grooves.

[0012] Furthermore, the hydraulic circulating drilling system includes a rotary drilling rig, which has a sliding hydraulic swivel rod capable of adjusting the drilling position. The output end of the sliding hydraulic swivel rod has a rotary drilling joint for connecting and driving the drill rod to rotate. The rotary drilling rig also has a clamping arm for limiting and straightening the drilling assembly.

[0013] Furthermore, the hydraulic circulating drilling rig system also includes a monitoring module, which is used to monitor mud parameters online, including but not limited to mud specific gravity and viscosity.

[0014] Furthermore, the mud circulation system includes a sedimentation zone and a mud storage zone that are laid out on the ground and interconnected. Both the sedimentation zone and the mud storage zone are equipped with mud pumps. The mud pump in the sedimentation zone is connected to the cavity through a mud pumping pipe, and the mud pump in the mud storage zone is connected to the inner cavity of the drill pipe through a mud supply pipe.

[0015] Furthermore, the steel section removal device also includes an electromagnetic control system, which controls the electromagnetic tube to be energized.

[0016] Furthermore, the electromagnetic tube includes multiple sleeves connected end to end, which are fitted and fixed to the outside of the drill pipe. The electromagnetic tube is made of soft magnetic material, including but not limited to silicon steel.

[0017] The present invention also provides a construction method for removing steel sections of a diaphragm wall, which is applied to any of the steel section removal devices described above, and includes the following steps: S1. Survey and set out the location of the steel section, level the construction ground and install the rotary drilling rig; S2. Arrange the mud circulation system, prepare circulating mud, install the mud circulation system, install circulation channels in the sedimentation zone and the mud storage zone, and install mud concentration detectors in the sedimentation zone and the mud storage zone respectively. S3. Arrange the hydraulic circulation drilling rig system, connect the mud circulation system and the hydraulic circulation drilling rig system, install the electromagnetic tube on the outside of the drill rod and match it with the electromagnetic control system, install the drill bit at the bottom of the drill rod, and install the inner cutter tube and the outer cutter tube in sequence on the outside of the drill bit. S4. Positioning drilling: After positioning is completed, drilling begins, and grout is injected into the drill pipe for mud circulation. S5. Drilling switch: Drill to the upper part of the diaphragm wall steel according to the measured depth, stop drilling, fix the outer cutter tube, and pull out the inner cutter tube to form a cavity between the drill bit and the outer cutter tube to provide a mud circulation environment. At the same time, the outer cutter tube wall isolates the surrounding soil and plays a mechanical protective role to prevent hole collapse. S6. Drilling steel section: The drill bit begins to cut the steel section inside the diaphragm wall. At the same time, the mud concentration in the borehole is monitored to ensure that the mud can lubricate and cool the drill bit. Simultaneously, the electromagnetic control system is activated to make the electromagnetic tube electromagnetically adsorb iron filings in the returning mud. S7. Regular cleaning and maintenance: Set corresponding working hours according to the needs of on-site obstacle removal, regularly pull up the drill bit to check the wear and replace the drill bit in time, and de-energize the solenoid tube to remove iron filings. S8. Repeat the construction until the steel inside the diaphragm wall is fully cut and removed. After the construction inspection is passed, clean the hole and remove the mud. S9. Construction is completed by removing the outer blade of the support pipe, backfilling with concrete, and clearing away all equipment and supporting systems from the site.

[0018] The beneficial effects of this invention are reflected in: 1. The diaphragm wall steel removal device of the present invention, with its composite design of electromagnetic tubes, integrates drilling, hole cleaning, wall protection, and steel obstacle removal into one unit, greatly reducing the need for frequent changes of mechanical equipment during construction. Furthermore, each part of the device can be replaced with components that meet site requirements, such as drill rod length, cutting edge thickness and material, and borehole size, thus possessing wide applicability.

[0019] 2. The core improvement of the diaphragm wall steel removal device of this invention lies in the adsorption treatment of iron filings generated during the steel cutting process using a silicon steel sleeve with an electromagnetic control system. This primarily addresses a problem inevitably encountered during underground steel cutting: the difficulty in removing iron filings from the borehole by circulating mud, which significantly impacts the efficiency of obstacle removal and drill bit wear. Furthermore, the demagnetizing property of the electrical silicon steel sleeve, being a soft magnetic material, facilitates the subsequent removal of adsorbed iron filings, truly achieving maximum construction convenience and efficiency.

[0020] 3. The inner and outer cutter tube design of the steel section removal device for diaphragm walls in this invention significantly improves the efficiency of the mud circulation system. The additional cavity formed after the inner cutter tube is removed allows the mud to fully contact the central drill bit, providing lubrication and cooling. Simultaneously, it allows iron filings generated during drill cutting to flow with the mud, creating suitable conditions for the electromagnetic control system to be energized and for the electromagnetic tube to fully adsorb the iron filings. Furthermore, with the outer cutter tube fixed, its specially designed corrugated outer wall provides a support effect equivalent to the strength of C20 concrete, effectively maintaining borehole wall stability even in environments such as gravel strata.

[0021] 4. The construction method for removing steel sections from underground diaphragm walls of the present invention can achieve rapid removal of steel sections inside underground diaphragm walls in actual working conditions, thereby maximizing construction clearance efficiency, reducing cumbersome construction steps, and minimizing equipment wear. It provides a new improved equipment reference for mechanical clearance of steel sections inside existing underground diaphragm walls and is worthy of promotion and use. Attached Figure Description

[0022] In the attached diagram: Figure 1 This is a schematic diagram of the overall structure of the device provided in Embodiment 1 of the present invention; Figure 2 for Figure 1 Schematic diagram of a medium-pressure circulating drilling rig system; Figure 3 for Figure 1 Schematic diagram of the medium mud circulation system; Figure 4 for Figure 1 A bottom view of the drilling assembly; Figure 5 for Figure 1 Schematic diagram of the drilling assembly and electromagnetic control system; Figure 6 This is a flowchart illustrating the construction method provided in Embodiment 2 of the present invention.

[0023] Explanation of reference numerals in the attached figures: 1. Hydraulic circulating drilling rig system; 101. Rotary drilling rig; 102. Sliding hydraulic rotary rod; 103. Rotary drilling joint; 104. Clamping arm; 2. Mud circulation system; 201. Pumping pipe; 202. Supply pipe; 203. Sedimentation zone; 204. Storage zone; 3. Drilling components; 301. Drill bit; 302. Inner cutting edge tube; 303. Outer cutting edge tube; 304. Drill rod; 4. Electromagnetic control system; 401. Electromagnetic tube. Detailed Implementation

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the invention, and not all of them. Unless otherwise specified, the embodiments and features described in this application can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0025] Example 1 Please combine Figures 1 to 5 A steel section removal device for diaphragm walls is designed for steel section joints within diaphragm walls with a diameter of less than one meter in the clearing hole. The device includes a drilling assembly 3, which comprises a drill bit 301. An inner cutting edge tube 302 and an outer cutting edge tube 303, which rotate synchronously with the drill bit 301, are nested sequentially on the outside of the drill bit 301. A drill rod 304, which drives the rotation of the drill bit 301, is located at the top of the drill bit 301. The drill pipe 304 has an inner cavity for conveying mud to the drill bit 301; By axially pulling the inner cutting edge tube 302 away from the outer cutting edge tube 303, a cavity for mud return is formed between the drill bit 301 and the outer cutting edge tube 303, and the drill bit 301 continues to advance to cut the steel in the continuous wall. An electromagnetic tube 401 is fixedly sleeved on the outside of the drill pipe 304. When energized, the electromagnetic tube 401 is magnetized to form a gradient magnetic field in the cavity, which adsorbs the steel debris carried in the return mud.

[0026] In this embodiment, the outer cutting edge tube 303 can be made of 42CrMo alloy steel and vacuum quenched to a hardness of HRC58-62. The inner cutting edge tube 302 (outer diameter Φ900mm) is made of the same material as the outer cutting edge tube 303 but uses a different heat treatment process. The drill bit 301 can be a tapered tungsten carbide drill bit with a tapered angle of approximately 135°.

[0027] In one embodiment, the front end of the outer cutting edge tube 303 protrudes beyond the front end of the inner cutting edge tube 302, and the front end of the inner cutting edge tube 302 protrudes beyond the front end of the drill bit 301. The front ends of both the outer cutting edge tube 303 and the inner cutting edge tube 302 have annular serrated structures.

[0028] Thus, the serrated structure at the front end of the outer blade tube 303 can first contact the ground and cut into the soil layer, and the serrated structure at the front end of the inner blade tube 302 will then perform secondary crushing of the cut soil. Finally, the drill bit 301 is responsible for guiding the crushing of the core area rock and soil.

[0029] In one embodiment, the outer peripheral sidewall of the outer knife-edge tube 303 has a corrugated tube structure to support the outer knife-edge tube 303 in the borehole. In this way, the specially designed corrugated tube outer wall of the outer knife-edge tube 303 can provide a support effect equivalent to the strength of C20 concrete, and can effectively maintain the stability of the borehole wall in environments such as sand and gravel strata.

[0030] It should be noted that the wall thickness of the outer knife-edge pipe 303 in this embodiment is 5cm, and its outer wall has an annular corrugated structure, which greatly enhances the ring stiffness of the outer knife-edge pipe 303, thereby enhancing the resistance of the outer knife-edge pipe 303 to soil load and achieving the effect equivalent to concrete wall support.

[0031] In one embodiment, an axially extending connecting block is provided on the inner side of the outer cutting edge tube 303 and the outer side of the drill bit 301, and a connecting groove is axially opened on the outer and inner sides of the inner cutting edge tube 302 to engage with the corresponding connecting block. The drill bit 301, the inner cutting edge tube 302, and the outer cutting edge tube 303 are kept rotating synchronously through corresponding connecting blocks and connecting grooves.

[0032] In this way, the drill bit 301, the inner cutting edge tube 302, and the outer cutting edge tube 303 maintain synchronous rotation through corresponding connecting blocks and connecting grooves to complete the drilling operation from the ground to the continuous wall. At the same time, it is convenient for the inner cutting edge tube 302 to be axially pulled out from the outer cutting edge tube 303, so that a cavity for mud return is formed between the drill bit 301 and the outer cutting edge tube 303.

[0033] In a specific implementation of the drilling assembly in this embodiment: When drilling begins, the serrated alloy cutter head at the front end of the outer cutter tube 303 first cuts into the soil layer. The spiral cutting edge at the front end of the inner cutter tube 302 then performs secondary crushing. The central drill bit 301 guides the crushing of the core soil and rock mass. When drilling reaches the location of the underground continuous wall steel section, the hydraulic locking device (which is existing technology, specifically located at the rotary drill joint 103, its main function being to fix the position of the outer cutter tube 303, a common drilling rig function) of the hydraulic circulating drilling rig system 1 will fix the outer cutter tube 303. Simultaneously, the servo motor (existing technology, located in the clamping arm of the hydraulic circulating drilling rig 1 for holding the outer cutter tube 303, with the servo motor output connected to...) will also be activated. On the inner cutter tube 302, the inner cutter tube 302 is driven to retract relative to the outer cutter tube 303 and the drill bit 301 to axially pull away the outer cutter tube 303, so that an annular cavity is formed between the outer cutter tube 303 and the drill bit 301 to serve as a return channel for mud circulation. The outer cutter tube 303 can provide a support effect equivalent to the strength of C20 concrete through its specially designed corrugated outer wall, and can still effectively maintain the stability of the borehole wall in environments such as sand and gravel strata.

[0034] The steel section removal device in this embodiment also includes a hydraulic circulating drilling system 1 and a mud circulation system 2; The hydraulic circulating drilling system 1 is used to pull the drilling assembly 3 to cut holes in the ground to the corresponding diaphragm wall steel.

[0035] The hydraulic circulating drilling system 1 of this embodiment includes a rotary drilling rig 101. The rotary drilling rig 101 has a sliding hydraulic swivel 102 that can adjust the drilling position. The output end of the sliding hydraulic swivel 102 has a rotary drilling joint 103 for connecting and driving the drill rod 304 to rotate. The rotary drilling rig 101 also has a clamping arm 104 for limiting and straightening the drilling assembly 3.

[0036] In addition, the hydraulic circulating drilling rig system 1 also includes a monitoring module, which is used to monitor mud parameters online, including but not limited to mud specific gravity and viscosity.

[0037] It should be noted that the hydraulic circulating drilling rig system 1 is the core equipment of the drilling project. It adopts a modular design of electric motor-hydraulic rod composite drive structure, in which the electric motor provides the power source and converts mechanical energy into hydraulic energy through a variable piston pump to drive the hydraulic cylinder to achieve precise feed control.

[0038] Preferably, the hydraulic circulation drilling system 1 of this application can be a pre-selected XR2600F rotary drilling rig. This model is equipped with an intelligent power matching system, with a maximum output torque of 260kN·m. Combined with a JS930-4×28 telescopic drill rod, it can efficiently complete underground continuous wall clearing operations up to a depth of 100m. The hydraulic circulation drilling system 1 provides a dual-mode switching function for forward and reverse circulation: in forward circulation mode, the mud flows downward through the inner cavity of the drill rod 304 and is ejected from the nozzle (not shown) on the drill bit 301, carrying drill cuttings upward along the annular gap of the borehole wall, suitable for working environments with soft soil and low groundwater levels; in reverse circulation mode, the mud rises rapidly along the inside of the drill rod 304, particularly suitable for construction environments with hard soil, rock formations, or high groundwater levels.

[0039] The mud circulation system 2 is used to transport mud to the inner cavity of the drill pipe 304 and to pump and recover mud from the cavity to form a mud circulation.

[0040] The mud circulation system 2 in this embodiment includes a sedimentation zone 203 and a mud storage zone 204 that are laid on the ground surface and are interconnected. Both the sedimentation zone 203 and the mud storage zone 204 are equipped with mud pumps. The mud pump in the sedimentation zone 203 is connected to the cavity through the mud pumping pipe 201, and the mud pump in the mud storage zone 204 is connected to the inner cavity of the drill pipe 304 through the mud supply pipe 202.

[0041] It should be noted that the mud circulation system 2 is a key supporting equipment in drilling engineering, mainly composed of three parts: sedimentation zone 203, mud storage zone 204, and circulation channel.

[0042] The sedimentation zone 203 is typically designed as a multi-stage sedimentation structure and equipped with purification devices such as vibrating screens and sand removers. The slurry storage area 204 is equipped with a liquid level monitoring and stirring device to ensure the stability of the slurry performance; The circulation channel includes components such as high-pressure pipelines, control valves, and flow meters. The high-pressure pipelines include the slurry extraction pipe 201 and the slurry supply pipe 202.

[0043] The mud circulation system 2 connects the slurry pump, the inner cavity of the drill rod 304, and the ground drilling hole through the electromagnetic tube 401, forming a complete closed circulation loop.

[0044] During operation, the slurry pump pressurizes the prepared drilling mud to 2-5 MPa and injects it into the inner cavity of the drill pipe 304 through a high-pressure pipeline. This forms a lubricating film at the drill bit 301, reducing frictional resistance. Simultaneously, it carries rock cuttings back through the annular gap between the drill pipe 304 and the borehole wall. The returned mud enters the sedimentation zone 203, where it undergoes sequential filtration via a vibrating screen, desanding via a cyclone separator, and gravity separation in a sedimentation tank. The purified mud is then returned to the storage zone 204 for later use. This circular design not only significantly improves drilling efficiency but also achieves a mud recycling rate of over 85%, combining economic benefits with environmental value.

[0045] In addition, the mud circulation system 2 is also equipped with a pressure sensor and a mud concentration detector, which can adjust the mud parameters in real time to adapt to the drilling needs of different formations.

[0046] During the process of cutting steel sections inside the diaphragm wall using traditional drilling rigs on site, steel debris is difficult to remove from the hole through mud circulation. It accumulates at the hole opening, greatly affecting the cutting efficiency of the drill bit and exacerbating drill bit wear.

[0047] Therefore, the steel section removal device in this embodiment also includes an electromagnetic control system 4, which controls the electromagnetic tube 401 to be energized.

[0048] In one embodiment, the solenoid tube 401 includes multiple sleeves connected end to end, which are sleeved and fixed to the outside of the drill pipe 304. The solenoid tube 401 is made of soft magnetic material, which includes, but is not limited to, silicon steel.

[0049] The casing is a seamless silicon steel casing with a double-layer structure: the inner layer consists of multiple sections of alloy steel pipe with a diameter of 100mm, and the outer layer is a DT4C electrical grade silicon steel casing with a wall thickness of 15mm.

[0050] It should be noted that because silicon steel is a soft magnetic material, the silicon steel sleeve can be magnetized according to the power supply conditions and demagnetized after the power is cut off. At the same time, the tungsten steel drill bit 301 has extremely weak magnetism and is basically unaffected by electromagnets.

[0051] During construction, the electromagnetic control system 4 magnetizes the electromagnetic tube 401, which consists of multiple casing sections, generating a magnetic attraction force. This creates a strong gradient magnetic field between the drill bit 301 and the casing in the cavity. Steel debris is attracted to the surface of the silicon steel casing by the gradient force of the magnetic field. When the drill bit 301 is raised to the surface outside the borehole, the electromagnetic control system 4 cuts off the power supply to demagnetize the silicon steel casing. Combined with high-pressure water jet washing, the attracted steel debris can be easily removed.

[0052] Example 2 Please combine Figure 6 This embodiment also provides a construction method for removing steel sections of a diaphragm wall, which is applied to the steel section removal device of Embodiment 1 above, and includes the following steps: S1. Survey and set out the location of the steel section, level the construction ground and install the rotary drilling rig 101; S2. Arrange the mud circulation system 2, prepare circulating mud, set up the mud circulation system 2, install a circulation channel between the sedimentation zone 203 and the storage zone 204, and install mud concentration detectors in the sedimentation zone 203 and the storage zone 204 respectively. S3. Arrange the hydraulic circulation drilling system 1, connect the mud circulation system 2 and the hydraulic circulation drilling system 1, install the electromagnetic tube 401 on the outside of the drill rod 304 and match it with the electromagnetic control system 4, install the drill bit 301 at the bottom of the drill rod 304, and install the inner cutter tube 302 and the outer cutter tube 303 in sequence on the outside of the drill bit 301. S4. Positioning drilling: After positioning is completed, drilling will begin, and grouting will be injected simultaneously to the drill rod at position 304 for mud circulation. S5. Drilling switch: Drill to the upper part of the diaphragm wall steel according to the measured depth, stop drilling, fix the outer cutter tube 303, and remove the inner cutter tube 302 to form a cavity between the drill bit 301 and the outer cutter tube 303 to provide a mud circulation environment. At the same time, the wall of the outer cutter tube 303 isolates the surrounding soil and plays a mechanical wall protection role to prevent hole collapse. S6. Drilling steel section, independently control drill bit 301 to continue advancing towards the steel section and begin cutting the steel section inside the diaphragm wall. At the same time, monitor the mud concentration in the borehole to ensure that the mud plays a sufficient role in lubricating the drill bit and cooling the drill bit 301. Simultaneously turn on the electromagnetic control system 4 to make the electromagnetic tube 401 electromagnetically adsorb the iron filings in the returning mud. S7. Regular cleaning and maintenance: Set corresponding working time according to the needs of on-site obstacle removal, regularly pull up the drill bit 301 to check the wear and replace the drill bit 301 in time, and de-energize the solenoid tube 401 to remove iron filings. S8. Repeat the construction until the steel inside the diaphragm wall is fully cut and removed. After the construction inspection is passed, clean the hole and remove the mud. S9. Construction is completed by removing the outer blade of the support pipe, backfilling with concrete, and clearing away all equipment and supporting systems from the site.

[0053] Based on this, the construction method of this application can achieve rapid removal of steel sections inside underground diaphragm walls in actual working conditions, thereby maximizing construction clearance efficiency, reducing cumbersome construction steps, and minimizing equipment wear. It provides a new improved equipment reference for mechanical clearance of steel sections inside existing underground diaphragm walls and is worthy of promotion and use.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0055] It should be noted that if the embodiments of the invention involve directional indicators (such as up and down), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0056] Furthermore, the meaning of "and / or" throughout the text includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution that satisfies both A and B. Additionally, if the embodiments of the invention involve descriptions such as "first," "second," etc., these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" can explicitly or implicitly include at least one of those features. Furthermore, "multiple" refers to two or more. Moreover, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the invention.

Claims

1. A steel section removal device for diaphragm walls, characterized in that, The drilling assembly (3) includes a drill bit (301), and the drill bit (301) is nested with an inner cutting edge tube (302) and an outer cutting edge tube (303) that can rotate synchronously with it. The top of the drill bit (301) is provided with a drill rod (304) that drives it to rotate. The drill pipe (304) has an inner cavity for conveying mud to the drill bit (301); By axially pulling the inner cutter tube (302) away from the outer cutter tube (303), a cavity for mud return is formed between the drill bit (301) and the outer cutter tube (303); An electromagnetic tube (401) is fixedly fitted on the outside of the drill rod (304). When energized, the electromagnetic tube (401) is magnetized to form a gradient magnetic field in the cavity, which adsorbs the steel debris carried in the return mud. The steel section removal device also includes a hydraulic circulating drilling system (1) and a mud circulation system (2); the hydraulic circulating drilling system (1) is used to pull the drilling rig assembly from the ground to cut the hole to the corresponding diaphragm wall steel section; the mud circulation system (2) is used to transport mud to the inner cavity of the drill rod (304) and to suck up and recover the mud in the cavity to form a mud circulation.

2. The steel section removal device for diaphragm walls as described in claim 1, characterized in that, The front end of the outer cutting edge tube (303) protrudes beyond the front end of the inner cutting edge tube (302), and the front end of the inner cutting edge tube (302) protrudes beyond the front end of the drill bit (301). The front ends of both the outer cutting edge tube (303) and the inner cutting edge tube (302) have annular serrated structures.

3. The steel section removal device for diaphragm walls as described in claim 1, characterized in that, The outer peripheral wall of the outer cutting edge tube (303) has a corrugated tube structure, which is used to support the outer cutting edge tube (303) in the borehole.

4. The steel section removal device for diaphragm walls as described in claim 1, characterized in that, The inner side of the outer blade tube (303) and the outer side of the drill bit (301) are provided with axially extending connecting blocks, and the outer side and inner side of the inner blade tube (302) are provided with axially extending connecting grooves that are inserted and matched with the corresponding connecting blocks. The drill bit (301), the inner cutting edge tube (302), and the outer cutting edge tube (303) maintain synchronous rotation through corresponding connecting blocks and connecting grooves.

5. The steel section removal device for diaphragm walls as described in claim 1, characterized in that, The hydraulic circulating drilling system (1) includes a rotary drilling rig (101), which has a sliding hydraulic swivel (102) that can adjust the drilling position. The output end of the sliding hydraulic swivel (102) has a rotary drilling joint (103) for connecting and driving the drill rod (304) to rotate. The rotary drilling rig (101) also has a clamping arm (104) for limiting and straightening the drilling assembly (3).

6. The steel section removal device for diaphragm walls as described in claim 5, characterized in that, The hydraulic circulating drilling rig system (1) also includes a monitoring module, which is used to monitor mud parameters online, including mud specific gravity and viscosity.

7. The steel section removal device for diaphragm walls as described in claim 1, characterized in that, The mud circulation system (2) includes a sedimentation zone (203) and a mud storage zone (204) that are laid out on the ground and interconnected. Both the sedimentation zone (203) and the mud storage zone (204) are equipped with mud pumps. The mud pump in the sedimentation zone (203) is connected to the cavity through a mud pumping pipe (201), and the mud pump in the mud storage zone (204) is connected to the inner cavity of the drill pipe (304) through a mud supply pipe (202).

8. The steel section removal device for diaphragm walls as described in claim 1, characterized in that, The steel section removal device also includes an electromagnetic control system (4), which controls the electromagnetic tube (401) to be energized.

9. The steel section removal device for diaphragm walls as described in claim 8, characterized in that, The electromagnetic tube (401) includes multiple sleeves connected end to end, which are sleeved and fixed on the outside of the drill rod (304). The electromagnetic tube (401) is made of soft magnetic material, including but not limited to silicon steel.

10. A construction method for removing steel sections from a diaphragm wall, wherein the method is applied to the steel section removal device as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1. Measure and set out the location of the steel section, level the construction ground and install the rotary drilling rig (101); S2. Arrange the mud circulation system (2), prepare circulating mud, set up the mud circulation system (2), install a circulation channel between the sedimentation zone (203) and the storage zone (204), and install mud concentration detectors in the sedimentation zone (203) and the storage zone (204) respectively. S3. Arrange the hydraulic circulating drilling system (1), connect the mud circulation system (2) and the hydraulic circulating drilling system (1), install the electromagnetic tube (401) on the outside of the drill rod (304) and match it with the electromagnetic control system (4), install the drill bit (301) at the bottom of the drill rod (304), and install the inner knife-edge tube (302) and the outer knife-edge tube (303) in sequence on the outside of the drill bit (301); S4. Positioning drilling: After positioning is completed, drilling begins, and grout is injected simultaneously to the drill rod (304) for mud circulation. S5. Drilling switch: Drill to the upper part of the diaphragm wall steel according to the measured depth, stop drilling, fix the outer cutter tube (303), and remove the inner cutter tube (302) so that a cavity is formed between the drill bit (301) and the outer cutter tube (303) to provide a mud circulation environment. At the same time, the outer cutter tube (303) wall isolates the surrounding soil and plays a mechanical wall protection role to prevent hole collapse. S6. Drilling steel section, the drill bit (301) begins to cut the steel section inside the diaphragm wall, while monitoring the mud concentration in the borehole to ensure that the mud plays a role in lubricating the drill bit (301) and cooling the drill bit (301). Simultaneously, the electromagnetic control system (4) is turned on, so that the electromagnetic tube (401) is energized and adsorbs the iron filings in the return mud. S7. Regular cleaning and maintenance: regularly pull the drill bit (301) out to the ground and demagnetize the solenoid tube (401) to remove iron filings; S8. Repeat the construction until the steel inside the diaphragm wall is fully cut and removed. After the construction inspection is passed, clean the hole and remove the mud.

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