Shield cutterhead and method for cutting reinforced concrete ground-connected wall in water-rich soft strata

Abstract

The present invention discloses a shield cutterhead for cutting reinforced concrete ground-connected walls in water-rich soft strata, the cutterhead is composed of a central installation panel and a cutter beam; the cutter beam includes a spoke-type cutter beam and a panel-type cutter beam, and is spaced around the central installation panel to form a circular cutterhead structure, the spoke-type cutter beam is connected to the central installation panel, the panel-type cutter beam is connected to the spoke-type cutter beam through an annular beam, and the outermost annular beam forms the outer ring of the cutterhead; the cutterhead is provided with a double-edged tearing knife, a bolted tearing knife, an advanced bolted tearing knife, a hob, a telescopic hob, a shell knife, and a scraper; the present invention designs a height step arrangement of the shield cutterhead tools suitable for cutting ground-connected walls in view of the structural characteristics of the ground-connected wall (the position of the main reinforcement in the wall, the diameter of the main reinforcement, and other reinforcement conditions). By designing the height steps of different tools, the wear of the tools is greatly reduced, and the cutting efficiency of the shield on the ground-connected wall is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of shield engineering, and in particular to a shield cutter head and a method for cutting reinforced concrete ground-connected walls in water-rich soft strata. Background Art

[0002] Under the technical background of a strong transportation country, subway construction has entered a peak period. The subway network is crisscrossed, and new subway lines will inevitably encounter obstacles from the reinforced concrete ground-connected walls of existing subway station enclosure structures. There are often no reserved conditions when the shield passes under the existing station. The shield needs to directly cut the reinforced concrete ground-connected walls, and the net distance between the shield and the existing station structure is extremely close, which places strict requirements on the safety control of the existing structure above. As the network becomes denser, this situation will become more and more common in the future.

[0003] The current traditional method is to reinforce it through horizontal freezing, grouting, etc., and then use manual chiseling to remove the ground-connected wall. The cost is high, the construction period is long, and the risk is high. However, the geological conditions in some areas do not support manual removal. The shield directly cuts through the reinforced concrete ground-connected wall. The cutter head configuration in the patent application with publication number CN103670428A can smoothly cut bridge piles; the cutter head in the patent application with publication number CN114991790A can smoothly cut the station pile foundation at close range, but the above two still have the risk of excessive cutter head torque and excessive tool damage when facing the ground-connected wall retaining structure with a reinforced concrete volume much larger than the pile foundation; the patent application with publication number CN113417651B provides a cutter head and construction method for cutting reinforced concrete structure, which uses a high-pressure abrasive jet to assist the tool to cut the steel bars in advance, but its high-pressure abrasive jet nozzle is very easy to get blocked, affecting the cutting efficiency and posing a safety risk. Summary of the invention

[0004] Purpose of the invention: In order to overcome the shortcomings of the background technology, the first purpose of the present invention is to disclose a shield cutterhead for cutting reinforced concrete ground-connected walls in water-rich soft strata;

[0005] The second purpose is to disclose a tunneling method using the above-mentioned water-rich soft strata to cut reinforced concrete ground-anchored wall shield cutter head.

[0006] Technical solution: The present invention discloses a cutterhead for cutting reinforced concrete ground-connected wall shield in water-rich soft strata, wherein the cutterhead is composed of a central mounting panel and a cutter beam;

[0007] The blade beams include spoke-type blade beams and panel-type blade beams, and are spaced around a central mounting panel to form a circular blade disc structure. The spoke-type blade beams are connected to the central mounting panel, and the panel-type blade beams are connected to the spoke-type blade beams through an annular beam, and the outermost annular beam forms an outer ring of the blade disc;

[0008] The knife disc is provided with a double-edged tearing knife, a bolted tearing knife, an advanced bolted tearing knife, a roller knife, a telescopic roller knife, a shell knife, and a scraper;

[0009] The double-edged tearing knives are arranged vertically and spaced apart and welded on the central mounting panel;

[0010] The bolted tearing knives are arranged in multiple radial intervals on each spoke-shaped knife beam and are distributed in a spiral line on all spoke-shaped knife beams;

[0011] The advanced bolted tearing knife is provided one on each spoke-shaped knife beam and is distributed in a spiral line on all spoke-shaped knife beams;

[0012] The roller cutter is arranged at the radially outermost side of each panel-shaped cutter beam;

[0013] The telescopic roller cutter is provided one on each spoke-shaped blade beam and is distributed in a spiral line on all spoke-shaped blade beams;

[0014] The shell cutters are arranged in multiple radial intervals on each panel-shaped cutter beam, and are also arranged in multiple circumferential intervals on the outer ring of the cutter disc;

[0015] A plurality of scrapers are radially arranged at intervals on both side edges of each spoke-shaped blade beam.

[0016] Furthermore, the central mounting panel and the blade beam are welded with Q345D steel plates and covered with 12.8 mm thick composite wear-resistant plates, and the outer periphery of the outer ring of the blade disc is welded with a 50 mm thick alloy wear-resistant plate.

[0017] Furthermore, there are six spoke-type blade beams and six panel-type blade beams, which are evenly spaced and distributed circumferentially.

[0018] Furthermore, the bolted tearing knife, the advanced bolted tearing knife and the telescopic roller are radially spaced and distributed on each spoke-type knife beam; the shell knife and the roller are radially spaced and distributed on each panel-type knife beam.

[0019] Furthermore, the blades of the bolted tearing knife, the advanced bolted tearing knife, the rolling knife, the telescopic rolling knife, and the shell knife are arranged circumferentially, and the blade of the scraper is arranged radially.

[0020] Furthermore, the telescopic roller cutter includes a cutter body, a cutter seat, a guide rail and guide shoe mechanism and a jack support; the cutter body is arranged in the cutter seat, and the cutter seat is arranged on the spoke-type cutter beam through the guide rail and guide shoe mechanism, and its back side is connected through a jack support to control the telescopic amount.

[0021] Further, the maximum blade height of the telescopic roller cutter>the blade height of the advanced bolted tearing knife>the blade height of the bolted tearing knife=the blade height of the roller cutter>the blade height of the shell cutter>the blade height of the scraper.

[0022] Furthermore, the opening rate of the cutter disc is 42%.

[0023] The tunneling method for cutting reinforced concrete ground-connected wall shield cutter head based on the above-mentioned water-rich soft stratum includes the following steps:

[0024] S1, grinding wall construction, using 2-3mm / min advancement speed, 0.6-0.8rpm cutter head speed grinding and cutting ground ties, control the penetration depth to 5mm;

[0025] S2: Shield tunneling and wall cutting. Adjust the telescopic roller cutter height to 230mm and first destroy the concrete structure of the ground-connected wall.

[0026] S3. When the telescopic cutter cuts and crushes the concrete on the surface of the ground-connected wall and is about to contact the main reinforcement of the ground-connected wall, the telescopic cutter is retracted, and the change in the cutter head torque and the cutter head advance are observed to comprehensively judge whether the shield cutter head has started to contact or has completed cutting the main reinforcement;

[0027] S4: During the shield excavation and pile cutting process, the advance tearing knife is 215mm high and first cuts the main reinforcement of the ground connection wall;

[0028] S5. Use bolted tearing knives, rollers and telescopic rollers with a height of 187.5mm to pull and cut steel bars at small intervals, and use shell knives with a height of 150mm and scrapers with a height of 130mm to collect the debris.

[0029] Beneficial effects: Compared with the prior art, the advantages of the present invention are:

[0030] 1. According to the structural characteristics of the ground-connected wall (the position of the main reinforcement in the wall, the diameter of the main reinforcement and other reinforcement conditions), the height step arrangement of the shield cutterhead tool suitable for cutting the ground-connected wall is designed. Through the height step design of different cutters, the wear of the cutters is greatly reduced, and the cutting efficiency of the shield on the ground-connected wall is greatly improved;

[0031] 2. In the project of shield cutting ground-connected wall, different tool height steps can be adjusted according to the cutting progress of the wall, and different tool height steps can also be adjusted according to ground-connected walls of different structures, making the shield cutterhead more applicable;

[0032] 3. While laying out more cutters, the cutter disc opening rate is increased as much as possible by setting spoke-type cutter beams and panel-type cutter beams at intervals. Two ring beams and the cutter beam are set to divide the cutter disc opening together, controlling the maximum particle size of the cutter disc and reducing the risk of the cutting material getting stuck in the spiral machine;

[0033] 4. The edge of the cutter disc is equipped with an edge roller, and the outermost trajectory line is equipped with a shell cutter to ensure the excavation diameter of the cutter disc and reduce the risk of the shield machine getting stuck during the wall grinding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1This is a structural diagram of the cutter head surface of the present invention;

[0035] Figure 2 This is a structural diagram of the telescopic hob surface of the present invention;

[0036] Figure 3 It is a side structural diagram of the telescopic hob of the present invention. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0038] like Figure 1 The cutterhead of the shield machine for cutting reinforced concrete ground-connected walls in water-rich soft strata shown in the figure is composed of a central mounting panel 1 and a cutter beam; the central mounting panel 1 and the cutter beam are welded with Q345D steel plates and covered with 12.8 mm composite wear-resistant plates, and a 50 mm thick alloy wear-resistant plate is welded on the outer periphery of the outer ring 5 of the cutterhead to improve the wear resistance of the cutterhead.

[0039] The blade beam includes 6 spoke-type blade beams 2 and 6 panel-type blade beams 3, which are spaced around a central mounting panel 1 to form a circular blade disc structure. The spoke-type blade beam 2 is connected to the central mounting panel 1, and the panel-type blade beam 3 is connected to the spoke-type blade beam 2 via an annular beam 4. The outermost annular beam 4 forms an outer ring 5 of the blade disc, and the opening rate of the blade disc is 42%.

[0040] The knife disc is provided with a double-edged tearing knife 6, a bolted tearing knife 7, an advanced bolted tearing knife 8, a roller knife 9, a telescopic roller knife 10, a shell knife 11, and a scraper 12;

[0041] The double-edged tearing knives 6 are arranged vertically and spaced apart and welded on the central mounting panel 1;

[0042] The bolted tearing knives 7 are arranged in multiple numbers at intervals on each spoke-shaped knife beam 2 in a radial direction and are distributed in a spiral line on all spoke-shaped knife beams 2;

[0043] The advanced bolted tearing knife 8 is provided on each spoke-shaped knife beam 2, and is distributed in a spiral line on all spoke-shaped knife beams 2;

[0044] The roller cutter 9 is arranged at the radially outermost side of each panel-shaped cutter beam 3, so as to achieve higher cutting efficiency for cement concrete structures;

[0045] The telescopic roller cutter 10 is provided on each spoke-shaped blade beam 2, and is distributed in a spiral line on all spoke-shaped blade beams 2;

[0046] The shell cutters 11 are arranged in multiple radial intervals on each panel-shaped cutter beam 3, and are also arranged in multiple circumferential intervals on the cutter disc outer ring 5;

[0047] The scrapers 12 are arranged in plurality at radial intervals on both side edges of each spoke-shaped blade beam 2 .

[0048] The bolted tearing knife 7, the advanced bolted tearing knife 8 and the telescopic roller cutter 10 are radially spaced and distributed on each spoke-type knife beam 2; the shell knife 11 and the roller cutter 9 are radially spaced and distributed on each panel-type knife beam 3.

[0049] The blades of the bolted tearing knife 7, the advanced bolted tearing knife 8, the rolling knife 9, the telescopic rolling knife 10 and the shell knife 11 are arranged circumferentially, and the blade of the scraper 12 is arranged radially.

[0050] like Figure 2 and 3 As shown, the telescopic roller cutter 10 includes a cutter body 10-1, a cutter seat 10-2, a guide rail and guide shoe mechanism 10-3 and a jack support 10-4; the cutter body 10-1 is arranged in the cutter seat 10-2, and the cutter seat 10-2 is arranged on the spoke-type cutter beam 2 through the guide rail and guide shoe mechanism 10-3, and its back side is connected through the jack support 10-4 to control the telescopic amount.

[0051] The maximum blade height of the telescopic roller cutter 10>the blade height of the advanced bolted tearing blade 8>the blade height of the bolted tearing blade 7=the blade height of the roller cutter 9>the blade height of the shell cutter 11>the blade height of the scraper 12.

[0052] The tearing knife is equipped with side and front protection alloys, and is designed with large radius corners and smaller penetration blunt edges. Compared with conventional tearing knives, the advanced tearing knife uses a larger alloy size, which has a higher cutting efficiency for steel bars and is easily worn when cutting cement concrete.

[0053] The tunneling method for cutting reinforced concrete ground-connected wall shield cutter head based on the above-mentioned water-rich soft stratum includes the following steps:

[0054] S1, grinding wall construction, using 2-3mm / min advancement speed, 0.6-0.8rpm cutter head speed grinding and cutting ground ties, control the penetration depth to 5mm;

[0055] S2, shield tunneling and wall cutting, adjust the telescopic roller cutter 10 to a height of 230mm, first destroy the concrete structure of the ground-connected wall, thereby reducing the loss of the concrete structure to the advanced tearing cutter;

[0056] S3, when the telescopic cutter 10 cuts and crushes the concrete on the surface of the ground-connected wall and is about to contact the main reinforcement of the ground-connected wall, the telescopic cutter 10 is retracted, and the change of the cutter head torque and the cutter head advance are observed to comprehensively judge whether the shield cutter head has started to contact or has completed cutting the main reinforcement;

[0057] S4, During the shield excavation and pile cutting process, the advanced tearing knife 8 with a height of 215mm first cuts the main reinforcement of the ground connection wall;

[0058] S5, bolted tearing knife 7, roller cutter 9 and telescopic roller cutter 10 with a height of 187.5mm are used to pull and cut the steel bars at small intervals, and shell cutter 11 with a height of 150mm and scraper 12 with a height of 130mm are used to collect the debris. If the roller cutter and bolted tearing knife are partially worn, the shell cutter becomes the first tool to contact the rock surface under this working condition, and also has the function of grinding piles and tearing steel bars. The scraper still maintains its original function under this action.

[0059] After the cutter disc has finished cutting the main reinforcement of the ground-connected wall, the retractable roller is properly pushed forward to continue to play its role in destroying the concrete.

[0060] During the construction of the first underground continuous wall, when the first and second layer tearing knives were severely damaged, it was necessary to open the warehouse and replace the knives, that is, to replace the bolted tearing knives with partial rolling knives or tearing knives through the freezing cutter disc solution.

[0061] After the cutter disc breaks the reinforced concrete, in order to ensure smooth output of the cut steel bars, an appropriate amount of foam or high-concentration bentonite slurry needs to be added during the screw conveyor conveying process, and full use should be made of the forward and reverse rotation of the screw conveyor and the telescopic screw conveyor to prevent the screw conveyor from getting stuck. If necessary, manual processing can be carried out through the screw conveyor observation window.

Claims

1. A shield cutterhead for cutting reinforced concrete ground-connected walls in water-rich soft strata. Features: The cutter disc is composed of a central mounting panel (1) and a cutter beam; The blade beam comprises a spoke-type blade beam (2) and a panel-type blade beam (3), and is spaced apart around a central mounting panel (1) to form a circular blade disc structure, wherein the spoke-type blade beam (2) is connected to the central mounting panel (1), and the panel-type blade beam (3) is connected to the spoke-type blade beam (2) via an annular beam (4), and the outermost annular beam (4) forms an outer ring (5) of the blade disc; The knife disc is provided with a double-edged tearing knife (6), a bolted tearing knife (7), an advanced bolted tearing knife (8), a rolling knife (9), a telescopic rolling knife (10), a shell knife (11), and a scraper (12); The double-edged tearing knives (6) are arranged vertically and spaced apart and welded on the central mounting panel (1); A plurality of the bolted tearing knives (7) are radially spaced apart on each spoke-shaped knife beam (2), and are distributed in a spiral line on all spoke-shaped knife beams (2); The advanced bolted tearing knife (8) is provided on each spoke-shaped knife beam (2), and is distributed in a spiral line on all spoke-shaped knife beams (2); The roller cutter (9) is arranged at the radially outermost side of each panel-shaped cutter beam (3); The telescopic roller cutter (10) is provided on each spoke-shaped blade beam (2), and is distributed in a spiral line on all spoke-shaped blade beams (2); A plurality of shell knives (11) are arranged at intervals in the radial direction on each panel-shaped knife beam (3), and a plurality of shell knives (11) are arranged at intervals in the circumferential direction on the outer ring (5) of the knife disc; A plurality of scrapers (12) are radially spaced apart on both side edges of each spoke-shaped blade beam (2); The central mounting panel (1) and the blade beam are welded with Q345D steel plates and covered with 12.8 mm thick composite wear-resistant plates, and the outer periphery of the blade disc outer ring (5) is welded with 50 mm thick alloy wear-resistant plates; The spoke-type blade beams (2) and the panel-type blade beams (3) are each provided with 6 blade beams, which are evenly spaced and distributed in the circumferential direction; The bolted tearing knife (7), the advanced bolted tearing knife (8) and the telescopic roller knife (10) are radially spaced and distributed on each spoke-type knife beam (2); the shell knife (11) and the roller knife (9) are radially spaced and distributed on each panel-type knife beam (3); The blades of the bolted tearing knife (7), the advanced bolted tearing knife (8), the rolling knife (9), the telescopic rolling knife (10), and the shell knife (11) are arranged circumferentially, and the blade of the scraper (12) is arranged radially; The telescopic hob (10) comprises a cutter body (10-1), a cutter seat (10-2), a guide rail and guide shoe mechanism (10-3) and a jack support (10-4); the cutter body (10-1) is arranged in the cutter seat (10-2), the cutter seat (10-2) is arranged on a spoke-shaped cutter beam (2) via the guide rail and guide shoe mechanism (10-3), and its back side is connected via the jack support (10-4) to control the telescopic amount; The maximum blade height of the telescopic roller cutter (10)>the blade height of the advanced bolted tearing blade (8)>the blade height of the bolted tearing blade (7)=the blade height of the roller cutter (9)>the blade height of the shell cutter (11)>the blade height of the scraper (12); The opening rate of the cutter disc is 42%.

2. Based on the tunneling method of the shield cutter head for cutting reinforced concrete ground-connected wall in water-rich soft strata as described in claim 1, It is characterized in that The following steps are involved: S1, grinding wall construction, using 2-3mm / min advancement speed, 0.6-0.8rpm cutter head speed grinding and cutting ground ties, control the penetration depth to 5mm; S2, shield tunneling and wall cutting, adjusting the telescopic roller cutter (10) to a height of 230 mm, first destroying the concrete structure of the ground-connected wall; S3, when the telescopic cutter (10) cuts and crushes the concrete on the surface of the ground-connected wall and is about to contact the main reinforcement of the ground-connected wall, the telescopic cutter (10) is retracted, and the change in the cutter head torque and the cutter head advance are observed to comprehensively judge whether the shield cutter head has started to contact or has completed cutting the main reinforcement; S4, during the shield tunneling pile grinding and wall cutting process, the advance tearing knife (8) with a knife height of 215 mm first cuts the main reinforcement of the ground connection wall; S5. Bolted tearing knives (7), rollers (9) and telescopic rollers (10) with a knife height of 187.5 mm are used to pull and cut steel bars at small intervals, and shell knives (11) with a knife height of 150 mm and scrapers (12) with a knife height of 130 mm are used to collect the debris.

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