Shield tunneling machine shell abandoning and disassembling construction method

Abstract

The invention relates to the technical field of shield construction, in particular to a shield machine shell abandoning and disassembling construction method which comprises the following steps that S1, a pressure bin is washed, the specific gravity of slurry in the pressure bin is reduced, and a discharging opening of the pressure bin is closed; grouting is conducted on the shield shell and the soil body within the first preset length range in the small mileage direction of the shield shell; s2, mortar is pressed into the pressure bin from bottom to top, so that the mortar is discharged from the valve above the pressure bin until the mortar flows out of the valve at the uppermost part of the pressure bin; s3, a retaining device is connected between the shield shell and the shield segment; and S4, the preset assembly in the shield shell is dismounted. The technical problems that existing shell abandoning and machine disassembling construction is insufficient in safety, and the risk of tunnel leakage or even collapse is large can be solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shield construction, in particular to a shield machine shell abandonment and disassembly construction method. BACKGROUND

[0002] Some existing tunnels are single-end tunnels, that is, the tunnel has an entrance only in the small mileage direction, but has no exit in the large mileage direction. When the shield machine completes the tunneling work of a predetermined length, it cannot directly exit the tunnel from the large mileage direction of the tunnel, and often can only be abandoned and disassembled. The general process of shell abandonment and disassembly is to first fill the cutter disc stratum in front of the shield machine through the reserved hole (the position of the ball valve and screw machine after disassembly) on the shield machine to stabilize the surrounding soil and prevent underground water from seeping into the construction area. Then, the reusable shield machine components (such as the thrust cylinder, articulated cylinder, pressure chamber (depending on the model of the shield machine, it may include a soil chamber, a slurry chamber, and an air cushion chamber), segment erector, and slag removal system (depending on the model of the shield machine, it may be a screw conveyor or a slurry pipeline), manway) are gradually removed, while the shield shell is left in place to support the end of the tunnel and prevent underground water from flowing into the tunnel from the large mileage direction of the tunnel.

[0003] However, the stability of the shield tunnel needs to be maintained by the continuous operation of key components such as the thrust cylinder and the pressure chamber. Therefore, during the shell abandonment and disassembly construction process, even if the shield shell is retained, the construction area still faces a high risk of leakage and collapse, and the softer the surrounding stratum, the greater the risk of shell abandonment and disassembly construction. For example, in the shell abandonment and disassembly construction of a certain nuclear power drainage single-end tunnel, the geology near the shutdown position of the shield machine is mainly silty sand, medium-coarse sand, completely weathered sandstone, and silty clay, which makes the traditional shell abandonment and disassembly method completely unsafe to implement, and therefore there is an urgent need for a shell abandonment and disassembly construction method with higher safety. SUMMARY

[0004] The present application aims to overcome the technical problems of insufficient safety of existing shell abandonment and disassembly construction and high risk of tunnel leakage and even collapse, and to provide a shield machine shell abandonment and disassembly construction method.

[0005] In a first aspect, the present application provides a shield machine shell abandonment and disassembly construction method, comprising the following steps: S1, washing the pressure chamber to reduce the specific gravity of the slurry in the pressure chamber, and closing the discharge port of the pressure chamber; grouting the shield shell and the soil in the first predetermined length range in the small mileage direction of the shield shell; S2, pressing the mortar into the pressure chamber from the bottom to the top, so that the slurry is discharged from the valve above the pressure chamber, until the mortar flows out of the uppermost valve of the pressure chamber; S3, connecting a stop device between the shield shell and the shield segment; S4, dismounting the predetermined components in the shield shell.

[0006] Preferably, the pressure chamber is divided into at least two segments in the height direction in S2, and the mortar is pressed into each segment from bottom to top and the slurry is discharged from each segment.

[0007] Preferably, S2 further comprises the following step: after the mortar flows out of the valve at the top of the pressure chamber, the grout is injected into the hole at the top of the shield shell using the lead drill until the grout injection pressure is greater than or equal to a predetermined threshold.

[0008] Preferably, S2 further comprises the following step: opening the valve of the pressure chamber to check the filling effect, and / or opening the slag discharge device behind the pressure chamber to check the filling effect.

[0009] Preferably, S2 further comprises the following step: using a secondary grouting machine to perform secondary grouting on the pressure chamber.

[0010] Preferably, S2 further comprises the following step: using a tensioning device to tension the shield segments within the second predetermined length range.

[0011] Preferably, S4 further comprises the following step: constructing a sealing wall on the side of the shield segment facing the large mileage direction, the cross-sectional shape and size of the sealing wall matching the cross-sectional shape and size of the shield shell; the sealing wall is provided with a pouring channel, and the two ends of the pouring channel communicate with the two sides of the sealing wall along the longitudinal direction of the tunnel; pouring cement mortar between the sealing wall and the shield shell through the pouring channel.

[0012] Preferably, a static pressure reading P1 in the pressure chamber is obtained before S2; in S2, the mortar is pressed into the pressure chamber at a predetermined pressure P2, P1≤P2≤1.5*P1.

[0013] Preferably, the mortar used in S2 has a strength grade greater than or equal to M10.

[0014] Preferably, the specific gravity of the slurry in the pressure chamber is reduced to less than or equal to one ton per cubic meter in S1.

[0015] Compared with the prior art, the present application has the following beneficial effects: The application provides a construction method for disassembling a shield shell, which can avoid the situation that mud cannot be replaced by sand mortar due to the excessive specific gravity of the mud, thereby ensuring that the area between the bottom of the pressure chamber and the valve at the top is filled with sand mortar, enabling the sand mortar to provide sufficient support effect on the shield shell, the working face and the surrounding soil, reducing the risk of deformation, displacement or even collapse of the shield shell under the action of earth pressure and water pressure, and reducing the risk of collapse of the working face and the surrounding soil of the pressure chamber, thereby improving the safety of the subsequent disassembly operation of the predetermined components and reducing the risk of leakage or even collapse of the tunnel.

[0016] The application also uses a retreat stopper to connect the shield shell and the shield segment, which can further prevent the shield shell from retreating towards the small mileage under the action of earth pressure and water pressure after the push oil cylinder is removed, thereby further reducing the risk of tunnel collapse, and can also transmit the earth pressure and water pressure acting on the shield shell to the shield segment, so that the adjacent shield segments can be pressed tightly by the earth pressure and water pressure, thereby further reducing the risk of tunnel leakage. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a construction step of a construction method for disassembling a shield shell of the application Figure 1 ; Figure 2 is a construction step of a construction method for disassembling a shield shell of the application Figure 2 ; Figure 3 is a construction step of a construction method for disassembling a shield shell of the application Figure 3 ; Figure 4 is a construction step of a construction method for disassembling a shield shell of the application Figure 4 ; Figure 5 is Figure 4 a partial enlarged structure diagram of the retreat stopper steel plate; Figure 6 is a construction step of a construction method for disassembling a shield shell of the application Figure 5 ; Figure 7 is a construction step of a construction method for disassembling a shield shell of the application Figure 6 ; FIG. 100-shield shell; 110-pressure chamber; 200-shield segment; 210-embedded steel plate; 211-first anchor; 212-second anchor; 300 - Retainer plate; 400 - Seal; 500 - Bulkhead; 510 - Pouring channel; 600 - Plain concrete bulkhead. DETAILED DESCRIPTION

[0018] The present application will be further described below in connection with specific embodiments. However, it should be understood that the above described subject matter of the present application is not limited to the following embodiments, but any technology achieved based on the content of the present application falls within the scope of the present application.

[0019] In the description of the embodiments of the present application, the terms of orientation or positional relationship such as "upper", "lower", "left", "right", "center", "inner", "outer", etc. are expressed based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product / device / apparatus of the present application is normally used. These terms of orientation or positional relationship are merely for the convenience of describing the present application or simplifying the description in the embodiments, and for the convenience of the skilled person to quickly understand the scheme, and do not indicate or imply that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship, and therefore cannot be understood as a limitation on the present application.

[0020] In addition, if the terms "horizontal", "vertical", "suspended", "parallel", etc. appear, it does not mean that the corresponding device / component / element must be absolutely horizontal or vertical or suspended or parallel, but can be slightly inclined or deviated. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined. Alternatively, it can be simplified to understand that the corresponding device / component / element is set in the direction of "horizontal", "vertical", "suspended", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction, more preferably an error / deviation of ±8% or less, more preferably an error / deviation of ±6% or less, more preferably an error / deviation of ±5% or less, and more preferably an error / deviation of ±4% or less. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present application.

[0021] In addition, the terms "first", "second", "third", etc. appearing in the terms are only used to distinguish the description of the same or similar parts, and should not be understood as emphasizing or implying the relative importance of a specific part.

[0022] In addition, in the description of the embodiments of the present application, "several", "a plurality of", "several" represent at least 2. It can be 2, 3, 4, 5, 6, 7, 8, 9, etc. in any case, or even more than 9.

[0023] Furthermore, in the description of the technical solutions of the present application, unless otherwise explicitly specified / limited / limited, the terms "arrangement", "installation", "connection", "connection", "provided with", "laid", "arrangement" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected, which can be welding, riveting, bolting, screwing and other commonly used connection means in the art. The connection can be mechanical connection, electrical connection or communication connection; it can be directly connected or indirectly connected through an intermediate medium; it can be the communication between two elements.

[0024] Embodiment 1 A shield machine shell dismantling construction method, comprising the following steps: S1, as shown in Figure 1 , open the washing function of the shield machine, pour clean water into the pressure chamber 110, and wash the pressure chamber 110; so as to reduce the specific gravity of the mud in the pressure chamber 110; close the discharge port of the pressure chamber 110, for example, if the shield machine is a earth pressure balance shield machine, close the gate of the screw conveyor; if the shield machine is a slurry balance shield machine, close the gate of the slurry pipeline; grouting the soil in the first predetermined length range of the shield shell 100 and the small mileage direction of the shield shell 100 to stabilize the soil around the shield machine and prevent groundwater from seeping into the tunnel.

[0025] S2, as shown in Figures 2 to 4 , connect the mortar pressure pipe to the existing valve (such as the ball valve connected to the pressure bearing partition plate of the pressure chamber 110) of the shield machine, and press the mortar into the pressure chamber 110 from bottom to top, so that the mud is discharged from the valve above the pressure chamber 110, until the mortar flows out of the uppermost valve, then the height of the uppermost valve and below the pressure chamber 110 is full of mortar; it should be noted that according to different types of shield machines, the actual number and position of the valve may be different, therefore Figures 1 to 4 The number and position of the valve are only a simplified schematic and are not used to limit the order of filling the chamber during actual construction. Figures 1 to 4

[0026] S3, as shown in Figure 4 and Figure 5 , connect the stop device between the inside wall of the shield shell 100 and the end face of the shield segment 200 facing the large mileage direction; it should be noted that the advancing oil cylinder will block the stop device in Figure 4 , therefore Figure 4 only the top stop device is drawn, and the top advancing oil cylinder is hidden, only to more clearly show the position of the stop device, not representing that the advancing oil cylinder must be removed at this step.

[0027] ​S4, disassemble the predetermined components in the shield shell 100, the specific disassembly target, disassembly method and sequence are determined according to the model of the shield machine and the actual construction demand, for example, for the earth pressure-mud dual mode shield machine, the articulated oil cylinder, the propulsion oil cylinder, the main machine and the trolley electric, gas, water and air pipe, the blocking mechanism of the first trolley, the segment trolley, the belt frame, the rear supporting trolley, the screw conveyor, the segment assembling machine, the working platform, the man cave, the air cushion cave, the main drive motor and the speed reducer can be disassembled in sequence.

[0028] Before disassembling the components in the shield shell 100, the specific disassembly target, disassembly method and sequence are determined according to the model of the shield machine and the actual construction demand, for example, for the earth pressure-mud dual mode shield machine, the articulated oil cylinder, the propulsion oil cylinder, the main machine and the trolley electric, gas, water and air pipe, the blocking mechanism of the first trolley, the segment trolley, the belt frame, the rear supporting trolley, the screw conveyor, the segment assembling machine, the working platform, the man cave, the air cushion cave, the main drive motor and the speed reducer can be disassembled in sequence.

[0029] The embodiment also uses the retreat stop device to connect the shield shell 100 and the shield segment 200, which can further prevent the shield shell 100 from retreating under the earth pressure and water pressure after the propulsion oil cylinder is disassembled, thereby further reducing the risk of tunnel collapse; on the other hand, it can also transmit the earth pressure and water pressure acting on the shield shell 100 to the shield segment 200, so that the adjacent shield segments 200 can be pressed tightly by the earth pressure and water pressure, thereby further reducing the risk of tunnel leakage.

[0030] In the optional implementation, the specific gravity of the mud in the pressure chamber 110 is reduced to less than or equal to one ton per cubic meter in S1, so as to ensure that the mud can be replaced by the sand slurry, and avoid the situation that the mud cannot be replaced by the sand slurry due to the excessive specific gravity.

[0031] In the optional implementation, the soil in the shield shell 100 and the thirty-ring shield segment 200 in the small mileage direction of the shield shell 100 is grouted in S1, that is, the first predetermined length is equal to the length of the thirty-ring shield segment 200; in addition, additional hoop grouting can be performed on the shield segment 200 closest to the shield tail to further prevent leakage accidents of the shield tail; after grouting is completed, the secondary grouting hole of the last ring shield segment 200 is opened as an observation hole, if no water flows out, it means that the grouting is successful, which can ensure that the shield tail does not leak; if water still flows out, the observation hole is changed to a grouting hole for continuous grouting, and if necessary, polyurethane can be injected, and the process is repeated until no clear water flows out from the observation hole.

[0032] In an optional implementation, the static pressure reading P1 in the pressure chamber 110 is obtained before S2; in S2, mortar is injected into the pressure chamber 110 at a predetermined pressure P2, where P1≤P2≤1.5*P1; for example, if the static pressure reading in the pressure chamber 110 is 500 kPa before the tunnel boring machine is abandoned and dismantled, then the pressure of the mortar can be controlled between 500 kPa and 750 kPa in S2.

[0033] This embodiment ensures that the mortar can generate sufficient support to replace the mud in supporting the shield shell 100 and the tunnel face. On the other hand, it also prevents excessive mortar pressure from causing excessive disturbance to the strata, pipeline damage, or even damage to the shield shell 100.

[0034] In an optional implementation, a synchronous grouting machine can be used in S2 to press mortar into the pressure chamber 110.

[0035] In an optional implementation, the mortar strength grade used in S2 is greater than or equal to M10 to ensure that the mortar can provide sufficient support for the shield shell 100, the tunnel face and the surrounding soil.

[0036] In an optional embodiment, in S2, the pressure chamber 110 is divided into at least two sections along the height direction, and mortar is gradually injected into each section from bottom to top and mud is discharged from each section, so as to avoid the situation where the mortar cannot fill the pressure chamber 110 or the density is insufficient due to the excessive diameter of the tunnel boring machine.

[0037] For example, pressure chamber 110 can be divided into an upper section and a lower section using the existing valves at the three o'clock and nine o'clock positions on the pressure-bearing partition of pressure chamber 110 as the dividing lines; correspondingly, S2 includes the following steps: S21, such as Figure 2 As shown, connect the mortar injection pipe to the valve at the bottom of the lower section's pressure-bearing diaphragm, and open the valves at the three o'clock and nine o'clock positions. Then, continuously inject mortar into the lower section through the mortar injection pipe, causing the slurry to be continuously discharged from the valves at the three o'clock and nine o'clock positions until... Figure 3 As shown, mortar is flowing out of the valves at the three o'clock and nine o'clock positions, indicating that the areas below the valves at the three o'clock and nine o'clock positions have been filled with mortar.

[0038] S21. Remove the mortar injection pipe installed in S21 and close the corresponding valve. Install mortar injection pipes on the valves at the three o'clock and nine o'clock positions, and open the valve at the top of the upper section's pressure-bearing partition. Continuously inject mortar into the upper section through the mortar injection pipe, causing the slurry to be continuously discharged from the valve at the top of the upper section until... Figure 4As shown, the mortar flows out of the uppermost valve of the upper section, which indicates that the area below the uppermost valve of the upper section has been filled with mortar.

[0039] In an optional embodiment, S2 further comprises the following step: after the mortar flows out of the uppermost valve of the pressure chamber 110, grouting is performed using the advance drill to the hole position on the top of the shield shell 100 (e.g. the existing grouting hole on the shield shell 100) until the grouting pressure is greater than or equal to the predetermined threshold value.

[0040] Since the height of the uppermost valve of the pressure chamber 110 is not necessarily at the highest point of the pressure chamber 110, if the pressure chamber 110 is filled by pressing the mortar into the pressure chamber 110 from bottom to top, the density of the part above the uppermost valve of the pressure chamber 110 may be insufficient; therefore, the advance drill is used to directly grout the hole position on the top of the shield machine in this embodiment, so that the grout can directly enter the pressure chamber 110 from top to bottom, thereby improving the density of the top of the pressure chamber 110 and further reducing the risk of damage to the shield shell 100 and tunnel collapse.

[0041] In an optional embodiment, the predetermined threshold value is 1.5 times the water and soil pressure, which has sufficient pressure to enhance the density of the mortar in the pressure chamber 110, and can prevent excessive disturbance of the surrounding soil during grouting operation, which may even cause damage to the shield shell 100.

[0042] In an optional embodiment, S2 further comprises the following steps: after the mortar flows out of the uppermost valve of the pressure chamber 110, waiting for the mortar to reach the designed strength (e.g. three days later), opening the valve of the pressure chamber 110 to check the filling effect, and / or opening the outlet of the slag removal device behind the pressure chamber 110 to check the filling effect; if no water flows out of the valve of the pressure chamber 110 or the opening of the slag removal device, it indicates that the filling effect of the pressure chamber 110 is good, and the subsequent construction can continue; if water flows out of the valve of the pressure chamber 110 or the opening of the slag removal device, it indicates that the filling effect of the pressure chamber 110 is insufficient, and the pressure chamber 110 needs to be grouted again.

[0043] The slag removal device is determined according to the model or operation mode of the shield machine, for example, for a soil pressure balance shield machine, a hole can be opened near the root of the screw conveyor close to the pressure chamber 110 and whether water flows out can be checked; for a slurry balance shield machine, a hole can be opened near the root of the slurry pipeline close to the pressure chamber 110 and whether water flows out can be checked.

[0044] In an optional embodiment, after S2, the method further comprises the following step: using a secondary grouting machine to perform secondary grouting on the pressure chamber 110 to fill the possible remaining gaps in the pressure chamber 110, thereby further increasing the compactness of the mortar in the pressure chamber 110, and further improving the supporting effect of the mortar on the shield shell 100 and the surrounding soil.

[0045] In an optional embodiment, if water flows out of the valve or the opening of the slag discharge device of the pressure chamber 110, it indicates that the compactness of the mortar in the pressure chamber 110 has not reached the required level. In this case, pure cement mortar is used for secondary grouting, i.e., the water-cement ratio is 1:1, to achieve rapid leak stopping and reinforcement.

[0046] In an optional embodiment, after S2, the method further comprises the following step: using a tensioning device to tension the adjacent shield segments 200 within the second predetermined length range. The tensioning device can be in the existing form, for example, using a channel steel to connect adjacent shield segments 200 to each other, and using bolts or wedges to generate a pre-tightening force. The second predetermined length is determined according to the actual construction situation, for example, it can be the length corresponding to ten rings of shield segments 200.

[0047] The embodiment can prevent the compression amount of adjacent shield segments 200 from decreasing or even separating from each other after the thrust cylinder is removed, thereby further reducing the risk of tunnel leakage.

[0048] In an optional embodiment, the retreat-preventing device in S3 can have various structures, including but not limited to a limiting structure such as a limiting block, a limiting column, or a limiting plate connected to the inner side of the shield shell 100, and the side of the limiting structure facing the small mileage direction abutting against the end of the shield segment 200; for example Figure 5 As shown, a pre-embedded steel plate 210 is arranged on the side of the shield segment 200 facing the large mileage direction, and a retreat-preventing steel plate 300 is connected to the pre-embedded steel plate 210. The retreat-preventing steel plate 300 is arranged along the longitudinal direction of the tunnel (for example, the normal of the retreat-preventing steel plate 300 is perpendicular to the longitudinal direction of the tunnel), and the side of the retreat-preventing steel plate 300 facing outward along the radial direction of the tunnel is connected to the inner side wall of the shield shell 100. At least two retreat-preventing steel plates 300 are distributed along the circumferential direction of the shield shell 100.

[0049] In an optional embodiment, the height (dimension along the radial direction of the tunnel) of the retreat-preventing steel plate 300 near the small mileage direction is greater than the height of the retreat-preventing steel plate 300 near the large mileage direction. For example, the retreat-preventing steel plate 300 can be triangular or right trapezoidal, so that the shape of the retreat-preventing steel plate 300 is more consistent with the actual stress characteristics of the retreat-preventing steel plate 300, thereby improving the material utilization efficiency of the retreat-preventing steel plate 300 and reducing material waste.

[0050] In an optional embodiment, after S4, the method further comprises the following step: as Figure 6As shown, the blocking wall 500 is constructed on the side of the shield segment 200 facing the large mileage direction, and the cross-sectional shape and size of the blocking wall 500 match those of the shield shell 100. A pouring channel 510 is reserved on the blocking wall 500, and the two ends of the pouring channel 510 respectively communicate with the two sides of the blocking wall 500 along the tunnel longitudinal direction. Figure 7 As shown, the pouring channel 510 is used to pour the cementitious concrete blocking 600 between the blocking wall 500 and the shield shell 100.

[0051] In this embodiment, the blocking wall 500 is first constructed on the end surface of the shield segment 200. The blocking wall 500 can further support the shield shell 100, thereby reducing the risk of collapse of the shield shell 100. The blocking wall 500 can also block the gap between the shield shell 100 and the shield segment 200, and isolate the space in the shield segment 200 from the space in the shield shell 100, thereby reducing the risk of leakage of the tunnel. After the completion of the blocking wall 500, the pouring channel 510 is further used to pour the cementitious concrete blocking 600 between the blocking wall 500 and the shield shell 100, thereby further supporting and blocking the shield shell 100, and further reducing the risk of collapse and leakage of the tunnel.

[0052] In optional embodiments, the specific form of the pouring channel 510 includes but is not limited to a through-hole structure provided on the blocking wall 500 or a pipe member embedded in the blocking wall 500. The number of pouring channels 510 can be one or more. The pouring channels 510 can be distributed along the tunnel circumference or the tunnel height direction, so as to pour the concrete to the side of the blocking wall 500 facing the large mileage direction in batches. Valves or plugs can be provided on the pouring channels 510, so as to close the pouring channels 510 after the completion of the construction of the cementitious concrete blocking 600, thereby preventing the underground water from flowing into the tunnel through the pouring channels 510.

[0053] In optional embodiments, the blocking wall 500 is a reinforced concrete member, which can ensure sufficient strength to support the shield shell 100 and can be relatively quickly and conveniently constructed in the tunnel. However, the blocking wall 500 can also be a steel structure or a steel-concrete structure.

[0054] In optional embodiments, the concrete strength grade of the cementitious concrete blocking 600 is greater than or equal to C40, so as to ensure sufficient strength to support the shield shell 100.

[0055] In optional embodiments, a sealing ring 400 is further provided between the shield segment 200 and the blocking wall 500, for example Figure 5As shown, the sealing ring 400 is arranged at the joint between the embedded steel plate 210 at the end of the shield segment 200 and the blocking wall 500; the sealing ring 400 can adopt existing products, including but not limited to a rubber sealing ring 400 or a water-swelling sealing ring 400; if the sealing ring 400 interferes with the retreat-stop device, a passage for the sealing ring 400 to pass through can be formed on the retreat-stop device, or the sealing ring 400 can be disconnected at the retreat-stop device, so as to avoid the interference between the sealing ring 400 and the retreat-stop device.

[0056] In an optional embodiment, the embedded steel plate 210 further has a first anchor 211 on the side facing the large mileage direction, the first anchor 211 is inserted into the blocking wall 500, and the connection reliability between the blocking wall 500 and the embedded steel plate 210 can be improved.

[0057] In an optional embodiment, at least two first anchors 211 are arranged on the embedded steel plate 210 along the radial direction of the tunnel, and the sealing ring 400 is located between the adjacent two first anchors 211 along the longitudinal direction of the tunnel.

[0058] The embodiment can further improve the connection reliability between the blocking wall 500 and the embedded steel plate 210 through more first anchors 211, and can limit the sealing ring 400 through the first anchors 211, so as to reduce the risk that the sealing effect of the sealing ring 400 is weakened due to the sealing ring 400 deviating from the designed position.

[0059] In an optional embodiment, the number of the sealing rings 400 is at least two, and the sealing rings 400 are distributed along the radial direction of the tunnel, so as to further improve the sealing effect of the sealing ring 400.

[0060] In an optional embodiment, the embedded steel plate 210 further has a second anchor 212 on the side facing the small mileage direction, the second anchor 212 is inserted into the shield segment 200, and the connection strength between the embedded steel plate 210 and the second anchor 212 can be improved.

[0061] In an optional embodiment, at least two second anchors 212 are arranged on the embedded steel plate 210 along the radial direction of the tunnel.

[0062] In an optional embodiment, the retreat-stop steel plate 300 is welded to the embedded steel plate 210, and / or the retreat-stop steel plate 300 is welded to the shield shell 100. The welding connection does not need to form a hole on the retreat-stop steel plate 300 or the shield shell 100, so as to ensure the connection strength and reduce the risk of tunnel leakage.

[0063] The above merely describes the preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method of construction for a shield machine shell removal, characterized in that, The method comprises the following steps: S1, washing the pressure chamber (110), reducing the specific gravity of the mud in the pressure chamber (110), and closing the discharge port of the pressure chamber (110); grouting the shield shell (100) and the soil in the first predetermined length range in the small mileage direction of the shield shell (100); S2, from bottom to top, press the mortar into the pressure chamber (110), so that the mud is discharged from the valve above the pressure chamber (110), until the mortar flows out of the uppermost valve of the pressure chamber (110); S3, connecting the stop device between the shield shell (100) and the shield segment (200); S4, removing the predetermined components in the shield shell (100).

2. The method according to claim 1, wherein, In S2, the pressure chamber (110) is divided into at least two sections along the height direction, and the mortar is gradually pressed into each section from bottom to top, and the mud in each section is discharged.

3. The method according to claim 1, wherein, S2 further comprises the following steps: after the mortar flows out of the uppermost valve of the pressure chamber (110), using the advance drill to grout the hole position at the top of the shield shell (100) until the grouting pressure is greater than or equal to the predetermined threshold.

4. The method according to claim 1, wherein, S2 further comprises the following steps: opening the valve of the pressure chamber (110) to check the filling effect, and / or opening the slag discharge device behind the pressure chamber (110) to check the filling effect.

5. The method of claim 1, wherein, S2 further comprises the following steps: using a secondary grouting machine to perform secondary grouting on the pressure chamber (110).

6. The method according to any one of claims 1 to 5, wherein, S2 further comprises the following steps: using a tensioning device to tension the shield segments (200) in the second predetermined length range.

7. The method according to any one of claims 1 to 5, wherein, S4 further comprises the following steps: constructing a sealing wall (500) on the side of the shield segment (200) facing the large mileage direction, the cross-sectional shape and size of the sealing wall (500) matching the cross-sectional shape and size of the shield shell (100); the sealing wall (500) is reserved with a pouring channel (510), both ends of the pouring channel (510) respectively communicating with both sides of the sealing wall (500) along the longitudinal direction of the tunnel; pouring cement (600) between the sealing wall (500) and the shield shell (100) through the pouring channel (510).

8. The method according to any one of claims 1 to 5, wherein, P1 is obtained before S2; in S2, the mortar is pressed into the pressure chamber (110) at a predetermined pressure P2, and P1≤P2≤1.5*P1.

9. The method according to any one of claims 1 to 5, wherein, The strength grade of the mortar used in S2 is greater than or equal to M10.

10. The method according to any one of claims 1 to 5, wherein, In S1, the specific gravity of the mud in the pressure chamber (110) is reduced to less than or equal to one ton per cubic meter.

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