Mortar spraying device and method for tunnel inner wall

Abstract

This invention discloses a mortar spraying device and method for tunnel inner walls. The device includes a detachable adapter frame mounted on a tunnel construction vehicle. A traveling member capable of moving along the arc shape of the tunnel is mounted on the adapter frame. A radial telescopic arm is mounted on the traveling member. The radial telescopic arm is connected to an adjustable double-head spraying mechanism via a sliding seat. A longitudinal drive mechanism is installed between the adjustable double-head spraying mechanism and the sliding seat. A wet elastic roller pressing mechanism is mounted on the adjustable double-head spraying mechanism. The method, based on the above device, enables continuous spraying of mortar onto the tunnel inner wall, ensuring firm adhesion of the mortar. This invention effectively improves spraying efficiency, avoids mortar loss, and ensures uniform mortar layer thickness, thus improving the quality of tunnel inner wall construction. This invention is applicable to the technical field of mortar spraying on tunnel inner walls.

Description

Technical Field

[0001] This invention belongs to the technical field of tunnel construction, specifically, it relates to a mortar spraying device and method for use on the inner wall of a tunnel. Background Technology

[0002] Currently, during tunnel construction, after the tunnel is excavated and formed by the tunnel boring machine, reinforcing bars need to be anchored to the inner wall of the tunnel, followed by the binding of the reinforcing bar skeleton. After binding, concrete mortar is sprayed onto the inner wall of the tunnel to cover the reinforcing bar skeleton, thereby ensuring the strength and smoothness of the tunnel inner wall. However, in the existing mortar spraying process, some mortar falls off the tunnel inner wall after being sprayed, affecting the quality of the spraying. To overcome this defect, it is necessary to check during spraying, and manually apply concrete mortar to fill in the missing areas of the sprayed layer. Moreover, existing spraying equipment often results in uneven spraying, leading to uneven thickness of the sprayed layer, which affects the strength of the tunnel inner wall. Therefore, there is an urgent need for a mortar spraying device to improve spraying efficiency, avoid mortar falling off, ensure uniform thickness of the sprayed layer, and improve the quality of tunnel inner wall construction. Summary of the Invention

[0003] This invention provides a mortar spraying device and method for use on the inner wall of tunnels, which improves spraying efficiency, avoids mortar loss, ensures uniform thickness of the sprayed mortar layer, and improves the quality of tunnel inner wall construction.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A mortar spraying device for use on the inner wall of a tunnel includes a transfer frame detachably mounted on a tunnel construction vehicle, a traveling member mounted on the transfer frame that can travel along the arc shape of the tunnel, a radial telescopic arm mounted on the traveling member, an adjustable double-head spraying mechanism connected to the radial telescopic arm via a sliding seat, a longitudinal drive mechanism mounted between the adjustable double-head spraying mechanism and the sliding seat, and a wet elastic roller pressing mechanism mounted on the adjustable double-head spraying mechanism.

[0006] Furthermore, the adapter frame includes an adapter seat detachably connected to the arched guide rail, the adapter seat being detachably connected to the tunnel construction vehicle; the traveling component is a moving slide, which is assembled on the arched guide rail and moves along the arched guide rail.

[0007] Furthermore, the sliding seat includes a seat body detachably connected to the radial telescopic arm, and a longitudinal slide rail extending along the tunnel length direction is constructed on the seat body, and the adjustable double-head spraying mechanism is slidably assembled on the longitudinal slide rail.

[0008] Furthermore, the longitudinal drive mechanism includes a drive motor mounted on the base, and a longitudinal lead screw coaxially connected to the output shaft of the drive motor. The longitudinal lead screw is threadedly connected to the lower part of the adjustable double-head spraying mechanism.

[0009] Furthermore, the adjustable dual-head spraying mechanism includes a spraying shell with symmetrical sliding strips on both sides of the lower part. The spraying shell is slidably connected to a longitudinal slide rail via the two sliding strips. A spraying cavity is formed inside the spraying shell. Two spray nozzles arranged in a V-shape are constructed at one end of the spraying shell near the tunnel perimeter wall. An inlet for slurry is opened on the spraying shell and communicates with the spraying cavity. The slurry delivery pipe communicates with the spraying cavity through the inlet for slurry.

[0010] Furthermore, a slurry adjusting component is provided inside the spraying chamber and between the inlet ends of the two spray nozzles. A connecting shaft with its axis is constructed at both ends of the slurry adjusting component. The two connecting shafts are rotatably connected to the two opposite end walls of the spraying shell. One of the connecting shafts is connected to the spraying shell through an angle adjusting component. A plate-shaped partition gate is movably connected at one end of the spraying shell near the tunnel perimeter wall and between the two spray nozzles. The end of the plate-shaped partition gate extending into the spraying chamber elastically abuts against the outer surface of the slurry adjusting component.

[0011] Furthermore, the angle adjustment component includes a power motor mounted on the spray shell, a first synchronous pulley coaxially mounted on the output shaft of the power motor, and a second synchronous pulley coaxially mounted on a corresponding connecting shaft. The first and second synchronous pulleys are connected by a synchronous transmission belt.

[0012] Furthermore, the slurry adjusting component is a hollow elastic rubber material structure with an elliptical cross-section. A connecting shaft is provided with a conductive channel communicating with the inner cavity of the slurry adjusting component. A medium conductive pipe is rotatably connected to the connecting shaft, and the medium conductive pipe communicates with the inner cavity of the slurry adjusting component through the conductive channel.

[0013] Furthermore, the wet elastic roller pressing mechanism includes two wet rollers arranged side by side. The circumference of each wet roller is covered with seepage holes that communicate with the inner cavity of the wet roller. A seepage layer is provided on the outer circumference of the wet roller. A connecting rod is coaxially constructed at both ends of each wet roller. Each connecting rod is rotatably connected to an elastic telescopic rod, and the elastic telescopic rod is fixed to the spray shell through a connecting plate. The connecting rods on the same side of the two wet rollers are rotatably connected to both ends of a connecting pipe. A connector pipe is installed on the connecting pipe, and a solenoid valve is installed at both ends of the connecting pipe.

[0014] The present invention also discloses a method for applying the above-described mortar spraying device to the inner wall of a tunnel, comprising the following steps:

[0015] Step 1. Drive the tunnel construction vehicle to the location in the tunnel where the coating will be applied;

[0016] Step 2. Control the radial telescopic arm to drive the adjustable dual-head spraying mechanism to move toward the tunnel wall to a predetermined distance;

[0017] Step 3. Start the mortar pump to pump the mortar in the mortar mixing tank into the adjustable double-head spraying mechanism, and then spray it onto the tunnel wall by the adjustable double-head spraying mechanism.

[0018] Step 4. During the shotcreting operation in Step 3, control the traveling component to move on the adapter frame, so that it drives the adjustable double-head spraying mechanism to move circumferentially along the tunnel wall. The adjustable double-head spraying mechanism moves from one side of the tunnel wall to the other side.

[0019] Step 5. During the spraying process, the wet elastic roller pressing mechanism performs wet roller pressing on the surface formed by spraying with water.

[0020] Step 6. When the adjustable dual-head spraying mechanism moves from one side of the tunnel wall to the other, the tunnel construction vehicle is erected and moves forward a predetermined distance; then the traveling parts are controlled to move in the opposite direction on the adapter frame to carry out the spraying operation synchronously.

[0021] Step 7. Repeat steps 1-6 to continuously spray the surface around the tunnel.

[0022] The technological advancements achieved by this invention compared to existing technologies, due to the aforementioned structure, are as follows: The invention drives a tunnel construction vehicle within the tunnel, stopping it at construction nodes. Then, it controls the radial telescopic arm to move towards the tunnel wall, causing the adjustable double-headed spraying mechanism to approach the tied steel reinforcement frame. Subsequently, it controls the traveling component to move on the adapter frame, causing the traveling component to drive the adjustable double-headed spraying mechanism in an arc motion via the radial telescopic arm. Simultaneously, it controls the adjustable double-headed spraying mechanism to perform spraying operations, achieving continuous circumferential spraying of mortar on the tunnel wall. During the spraying process, the use of the adjustable double-headed spraying mechanism enables primary and secondary spraying, resulting in the formation of a primary sprayed mortar layer and a secondary sprayed mortar layer on the tunnel wall, with the secondary sprayed mortar layer located outside the primary sprayed mortar layer. The wet elastic roller pressing mechanism of this invention elastically rolls the primary shotcrete layer in a wet state, gradually densifying the primary shotcrete layer and improving the adhesion strength between the primary shotcrete layer and the tunnel inner wall. Furthermore, due to the wet rolling process, adhesion between the wet elastic roller pressing mechanism and the primary shotcrete layer is less likely, preventing damage to the surface of the primary shotcrete layer. The secondary shotcrete layer of this invention supplements the primary shotcrete layer, ensuring a smooth and even tunnel surface after shotcreting. Simultaneously, after the wet elastic roller pressing mechanism rolls the primary shotcrete layer, a liquid bonding film forms on its surface. When the secondary shotcrete layer forms on this liquid bonding film, the surface tension of the liquid bonding film ensures that the secondary shotcrete layer, which is much thinner than the primary shotcrete layer, remains firmly attached to it. Over time, the liquid bonding film gradually penetrates into both the primary and secondary shotcrete layers, ultimately forming a unified structure. After completing the circumferential spraying of a certain area of ​​the tunnel, this invention controls the tunnel construction vehicle to move along the length of the tunnel to the next node, and continues to repeat the above-mentioned spraying operation. This invention can also control the tunnel construction vehicle to move forward while spraying, so that the tunnel inner wall is continuously sprayed in a wavy, meandering pattern, with adjacent spraying trajectories partially overlapping, to avoid incomplete spraying and ensure sufficient coverage. In summary, this invention can effectively improve spraying efficiency, avoid slurry loss, ensure uniform thickness of the sprayed layer, and improve the quality of tunnel inner wall construction. Attached Figure Description

[0023] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0024] In the attached diagram:

[0025] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention;

[0026] Figure 2This is a schematic diagram of the connection between the adapter frame and the traveling member in an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the structure after removing the adapter frame and traveling parts in an embodiment of the present invention;

[0028] Figure 4 for Figure 3 Side view of the structure shown;

[0029] Figure 5 This is a schematic diagram of the connection between the adjustable dual-head spraying mechanism and the wet elastic roller pressing mechanism in an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the connection between the radial telescopic arm, the sliding seat, and the longitudinal drive mechanism in an embodiment of the present invention.

[0031] Figure 7 This is a schematic diagram of the adjustable dual-head spraying mechanism according to an embodiment of the present invention;

[0032] Figure 8 This is a cross-sectional view of the adjustable dual-head spraying mechanism according to an embodiment of the present invention;

[0033] Figure 9 This is a schematic diagram showing the connection between the slurry adjustment component and the angle adjustment assembly in the adjustable dual-head spraying mechanism of this invention.

[0034] Figure 10 This is a schematic diagram of the structure of the wet elastic roller pressing mechanism according to an embodiment of the present invention.

[0035] Components labeled: 100-Adapter frame, 101-Adapter base, 102-Archive guide rail, 200-Radial telescopic arm, 300-Sliding seat, 301-Seat body, 302-Longitudinal slide rail, 400-Adjustable double-head spraying mechanism, 401-Spraying shell, 402-Sliding strip, 403-Slurry inlet, 404-Spraying chamber, 405-Spray nozzle, 406-Slurry adjustment component, 407-Conducting channel, 408-Plate-shaped separator, 409-Connecting ear, 410-Conical spring, 411-Media conduit, 412-Connecting shaft. 413-Power motor, 414-First synchronous pulley, 415-Second synchronous pulley, 416-Synchronous transmission belt, 417-Slurry conveying pipe, 418-Transmission ear, 500-Wet elastic roller pressing mechanism, 501-Wet pressing roller, 502-Adapter ring, 503-Plug-in rod, 504-Plug-in pipe, 505-Telescopic spring, 506-Adapter plate, 507-Connecting pipe, 508-Solenoid valve, 509-Connector pipe, 600-Longitudinal drive mechanism, 601-Drive motor, 602-Longitudinal lead screw, 700-Motion slide. Detailed Implementation

[0036] The preferred embodiments of the present invention will now be described with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0037] This invention discloses a mortar spraying device for use on the inner wall of a tunnel, such as... Figure 1-10As shown, the system includes a transfer frame 100, a traveling member, a radial telescopic arm 200, a sliding seat 300, an adjustable double-head spraying mechanism 400, a longitudinal drive mechanism 600, and a wet elastic roller pressing mechanism 500. The transfer frame 100 is detachably mounted on the tunnel construction vehicle. The traveling member is mounted on the transfer frame 100 and can travel along the arc shape of the tunnel. The radial telescopic arm 200 is mounted on the traveling member and is connected to the adjustable double-head spraying mechanism 400 via the sliding seat 300. The longitudinal drive mechanism 600 is installed between the adjustable double-head spraying mechanism 400 and the sliding seat 300. The wet elastic roller pressing mechanism 500 is mounted on the adjustable double-head spraying mechanism 400. The working principle and advantages of this invention are as follows: The invention drives a tunnel construction vehicle inside the tunnel. At a construction node, the tunnel construction vehicle stops. Then, the radial telescopic arm 200 is controlled to move towards the inner wall of the tunnel, causing it to drive the adjustable double-head spraying mechanism 400 to approach the tied steel reinforcement frame. Afterward, the traveling component is controlled to move on the adapter frame 100, causing the traveling component to drive the adjustable double-head spraying mechanism 400 in an arc motion via the radial telescopic arm 200. Simultaneously, the adjustable double-head spraying mechanism 400 is controlled to perform spraying operations, achieving continuous circumferential spraying of mortar on the tunnel wall. During the spraying process, due to the use of the adjustable double-head spraying mechanism 400, primary and secondary spraying are achieved, resulting in the formation of a primary spraying layer and a secondary spraying layer on the inner wall of the tunnel, with the secondary spraying layer located outside the primary spraying layer. The wet elastic roller pressing mechanism 500 of this invention elastically rolls the primary shotcrete layer in a wet state, gradually densifying the primary shotcrete layer and improving the adhesion strength between the primary shotcrete layer and the tunnel inner wall. Furthermore, due to the wet rolling process, adhesion between the wet elastic roller pressing mechanism 500 and the primary shotcrete layer is less likely, preventing damage to the surface of the primary shotcrete layer. The secondary shotcrete layer of this invention supplements the primary shotcrete layer, ensuring a smooth and even tunnel surface after shotcreting. Simultaneously, after the wet elastic roller pressing mechanism 500 rolls the primary shotcrete layer, a liquid bonding film forms on the surface of the primary shotcrete layer. When the secondary shotcrete layer forms on this liquid bonding film, the surface tension of the liquid bonding film ensures that the secondary shotcrete layer, which is much thinner than the primary shotcrete layer, remains firmly attached to the primary shotcrete layer. Over time, the liquid bonding film gradually penetrates into both the primary and secondary shotcrete layers, ultimately forming a unified structure. After completing the circumferential spraying of this area of ​​the tunnel, this invention controls the tunnel construction vehicle to move along the length of the tunnel to the next node, and continues to repeat the above-mentioned spraying operation. This invention can also control the tunnel construction vehicle to move forward while spraying, so that the inner wall of the tunnel is continuously sprayed in a wave-like and meandering pattern, and the adjacent spraying trajectories partially overlap, in order to avoid incomplete spraying and ensure sufficient spraying.In summary, the present invention can effectively improve spraying efficiency, avoid grout loss, ensure uniform thickness of the sprayed layer, and improve the quality of tunnel inner wall construction.

[0038] As a preferred embodiment of the present invention, such as Figure 2 As shown, the adapter frame 100 includes an adapter seat 101 and an arched guide rail 102. The adapter seat 101 is detachably connected to the arched guide rail 102 and is also detachably connected to the tunnel construction vehicle. In this embodiment, the traveling component is a motion slide 700, which is mounted on the arched guide rail 102 and can move along the extension direction of the arched guide rail 102. In this embodiment, the shape of the arched guide rail 102 is the same as the cross-sectional shape of the tunnel. The size of the arched guide rail 102 is 1 / 5 to 1 / 4 of the tunnel's cross-sectional size, making it easier for the traveling component to drive the adjustable double-head spraying mechanism 400 and ensuring sufficient spraying by the adjustable double-head spraying mechanism 400, avoiding dead angles. In this embodiment, the radial telescopic arm 200 generally uses a hydraulic cylinder or a pneumatic cylinder.

[0039] As a preferred embodiment of the present invention, such as Figure 3-6 As shown, the sliding seat 300 includes a seat body 301 and a longitudinal slide rail 302. The seat body 301 is detachably connected to the end of the radial telescopic arm 200 away from the traveling member. The longitudinal slide rail 302 is constructed on the seat body 301 and extends along the length direction of the tunnel. The adjustable double-head spraying mechanism 400 is slidably mounted on the longitudinal slide rail 302. The longitudinal drive mechanism 600 of this embodiment includes a drive motor 601 and a longitudinal lead screw 602. The drive motor 601 is mounted on the seat body 301, and the longitudinal lead screw 602 is coaxially connected to the output shaft of the drive motor 601. A transmission lug 418 is constructed at the lower part of the adjustable double-head spraying mechanism 400, and the longitudinal lead screw 602 is threadedly connected to the transmission lug 418. The working principle and advantages of this embodiment are as follows: This embodiment controls the operation of the drive motor 601 to drive the longitudinal screw 602 to rotate. Under the transmission of the longitudinal screw 602, the adjustable double-head spraying mechanism 400 moves along the length of the tunnel. When the tunnel construction vehicle is not in motion, it can perform longitudinal spraying operations on the inner wall of the tunnel in the target area. In conjunction with the traveling parts reciprocating on the arched guide rail 102, the spraying range is increased and the frequent start and stop of the tunnel construction vehicle is avoided.

[0040] As a preferred embodiment of the present invention, such as Figure 3 , 5As shown in Figures 7 and 8, the adjustable dual-head spraying mechanism 400 includes a spraying shell 401. Sliding strips 402 are symmetrically constructed on both sides of the lower part of the spraying shell 401. The spraying shell 401 is slidably connected to the longitudinal slide rail 302 through these two sliding strips 402. A spraying cavity 404 is formed inside the spraying shell 401. Two spray nozzles 405 are constructed at one end of the spraying shell 401 near the tunnel perimeter wall. These two spray nozzles 405 are arranged in a V-shape. A slurry inlet 403 is opened on the spraying shell 401. The slurry inlet 403 is connected to the spraying cavity 404. The slurry conveying pipe 417 is connected to the spraying cavity 404 through the slurry inlet 403. In this embodiment, the mortar is pressurized and supplied to the spraying chamber 404 through the mortar delivery pipe 417, and then sprayed out by two spray nozzles 405. As the spray shell 401 is driven to move along the circumference of the tunnel, the two spray nozzles 405 achieve the purpose of secondary spraying on the inner wall of the tunnel, so that a primary sprayed mortar layer and a secondary sprayed mortar layer are formed on the inner wall of the tunnel in sequence.

[0041] As a preferred embodiment of the present invention, such as Figure 7-9As shown, a slurry adjusting component 406 is provided in the spraying cavity 404. The slurry adjusting component 406 is located between the inlet ends of the two spray nozzles 405. Connecting shafts 412 are respectively constructed at both ends of the slurry adjusting component 406. The axis of the slurry adjusting component 406 coincides with the axis of the two connecting shafts 412, and the two connecting shafts 412 are rotatably connected to the two opposite end walls of the spraying shell 401. One of the connecting shafts 412 is connected to the spray shell 401 via an angle adjustment assembly. A plate-shaped separator 408 is movably connected to one end of the spray shell 401 near the tunnel wall. The plate-shaped separator 408 is located between the two spray nozzles 405, and one end of the plate-shaped separator 408 extending into the spray cavity 404 elastically abuts against the outer surface of the slurry adjusting component 406. The plate-shaped separator 408 is used to separate the connecting parts of the two spray nozzles 405 near the tunnel wall, preventing the two spray nozzles 405 from connecting except at the inlet end, thereby affecting the different slurry output of the two spray nozzles 405 and making it impossible to achieve the effect that the thickness of the primary spray layer is greater than the thickness of the secondary spray layer. Furthermore, in this embodiment, the flow rate and pressure of the slurry entering the two spray nozzles 405 can be adjusted by adjusting the angle adjustment component. Simultaneously, the position of the plate-shaped partition gate 408 changes accordingly, ensuring it remains in a separated state. This allows for adjustment of the spray volume and pressure of the two spray nozzles 405, thereby adjusting the thickness of the primary and secondary spray layers, ensuring a stable bond and firm adhesion to the inner wall of the tunnel. In this embodiment, two connecting ears 409 are symmetrically constructed at the end of the plate-shaped partition gate 408 extending from the spray cavity 404. These two connecting ears 409 are located at both ends of the length direction of this end of the plate-shaped partition gate 408. A conical spring 410 is fixed to both sides of each connecting ear 409, and the other end of each conical spring 410 is fixedly connected to the outer wall of the spray shell 401. In this embodiment, the plate-shaped separator 408, under the action of the conical spring 410, has one end extending into the spraying cavity 404 that always elastically presses against the corresponding surface of the slurry adjusting member 406, thereby achieving a blocking effect. Alternatively, a linear electric cylinder can be used instead of the conical spring 410 in this embodiment. A spring is installed on the cylinder rod of the linear electric cylinder, and the spring is connected to the outer end of the plate-shaped separator 408. The cylinder body of the linear electric cylinder is connected to the outer surface of the spraying shell 401, and the linear electric cylinder extends along the insertion direction of the plate-shaped separator 408. In this embodiment, during the adjustment of the slurry adjusting member 406, the linear electric cylinder is controlled to move, and under the action of the spring, the end of the plate-shaped separator 408 always elastically presses against the slurry adjusting member 406 with a predetermined pressure, thereby improving the blocking effect of the plate-shaped separator 408. The specific structure of the angle adjustment component in this embodiment is as follows: the angle adjustment component includes a power motor 413, a first synchronous pulley 414, a second synchronous pulley 415, and a synchronous transmission belt 416.In this embodiment, the power motor 413 is mounted on the spray shell 401, the first synchronous pulley 414 is coaxially mounted on the output shaft of the power motor 413, and the second synchronous pulley 415 is coaxially mounted on the corresponding connecting shaft 412. The first synchronous pulley 414 and the second synchronous pulley 415 are connected by a synchronous transmission belt 416. Specifically, the slurry adjusting component 406 is a hollow elastic rubber material with an elliptical cross-section. A guiding channel 407 is provided on one of the connecting shafts 412, communicating with the inner cavity of the slurry adjusting component 406. A medium guiding pipe 411 is rotatably connected to this connecting shaft 412, communicating with the inner cavity of the slurry adjusting component 406 through the guiding channel 407. The working principle and advantages of this embodiment are as follows: Since the slurry adjusting component 406 is made of hollow elastic rubber material, when the high-pressure medium is introduced into the inner cavity of the slurry adjusting component 406 through the medium conduction pipe 411 and the conduction channel 407, the slurry adjusting component 406 expands under the drive of the high-pressure medium, thereby changing the flow rate and pressure of the slurry entering the inlet end of the two spray nozzles 405, so that the pressure and spray volume of the mortar coming out of the two spray nozzles 405 are changed, thus achieving the purpose of simultaneously adjusting the thickness of the primary spray layer and the secondary spray layer. In this embodiment, the angle adjustment component is controlled to rotate the slurry adjustment component 406 within the spraying cavity 404 by a certain angle. This increases the flow rate of one spray nozzle 405 while decreasing the flow rate of the other spray nozzle 405. The spray nozzle 405 with the larger flow rate is used for spraying the primary spray layer, and the spray nozzle 405 with the smaller flow rate is used for spraying the secondary spray layer. After the traveling member moves from one end of the arched guide rail 102 to the other end, it is controlled to move in the opposite direction along the arched guide rail 102. At this time, the angle adjustment component is activated to rotate the slurry adjustment component 406 within the spraying cavity 404 until the spraying flow rates of the two spray nozzles 405 are interchanged. In this way, during the reverse movement of the adjustable dual-head spraying mechanism 400, the primary and secondary spray layers are sequentially sprayed and formed. In this embodiment, the rotation angle of the slurry adjusting component 406 can be adjusted via an angle adjusting assembly, thereby adjusting the thickness of the primary and secondary shotcrete layers. Specifically, when the thickness of the primary shotcrete layer increases, the thickness of the secondary shotcrete layer decreases; conversely, when the thickness of the primary shotcrete layer decreases, the thickness of the secondary shotcrete layer increases. This embodiment also achieves the purpose of simultaneously increasing or decreasing the thickness of the primary and secondary shotcrete layers by either expanding the slurry adjusting component 406 with the medium or by discharging some of the medium from the slurry adjusting component 406, thus changing the degree of expansion of the slurry adjusting component 406.

[0042] As a preferred embodiment of the present invention, such as Figure 3 , 5As shown in Figure 10, the wet elastic roller pressing mechanism 500 includes two wet rollers 501, which are arranged side by side at one end of the spray shell 401 near the tunnel perimeter wall and located between two spray nozzles 405. The axis of each wet roller 501 extends along the length of the tunnel. Water seepage holes communicating with the inner cavity of each wet roller 501 are distributed on the circumference of each wet roller 501, and a water seepage layer is provided on the outer circumference of each wet roller 501. A connecting rod is coaxially constructed at both ends of each wet roller 501, and an elastic telescopic rod is rotatably connected to each connecting rod. The elastic telescopic rod is fixed to the spray shell 401 via a connecting plate 506. The connecting rods on the same side of the two wet rollers 501 are rotatably connected to both ends of a connecting pipe 507. A connector pipe 509 is installed on the connecting pipe 507, and a solenoid valve 508 is installed at each of the two ends of the connecting pipe 507. The elastic telescopic rod of this embodiment includes a plug rod 503, a plug tube 504, a transition ring 502, and a telescopic spring 505. The transition ring 502 is rotatably mounted on the corresponding transition rod. The plug rod 503 is constructed on the transition ring 502. One end of the plug rod 503 away from the transition ring 502 is movably inserted into the plug tube 504. The telescopic spring 505 is mounted on the outside of the plug rod 503. The two ends of the telescopic spring 505 are respectively connected to the transition ring 502 and the plug tube 504. The plug tube 504 is fixed to the spray shell 401 through the transition plate 506. The working principle and advantages of this embodiment are as follows: Liquid is introduced into the wet pressure roller 501 through the connecting pipe 507. The liquid seeps into the seepage layer through the seepage holes, saturating the seepage layer and ensuring the formation of a liquid film on its surface. This prevents the wet pressure roller 501 from sticking to the primary sprayed mortar layer during elastic rolling, ensuring a smooth surface after rolling. Furthermore, this embodiment uses two wet pressure rollers 501 to roll the primary sprayed mortar layer twice, ensuring its density and surface smoothness. The solenoid valve 508 can be controlled to adjust the amount of liquid entering the wet pressure roller 501, preventing the liquid film from becoming too thick and ensuring the bonding strength between the secondary and primary sprayed mortar layers. The liquid film should not be too thin, as this can cause the wet pressure roller 501 to stick to the surface of the primary sprayed mortar layer, affecting the quality of the mortar spraying application.

[0043] The present invention also discloses a method for applying the above-described mortar spraying device to the inner wall of a tunnel, comprising the following steps:

[0044] Step 1. Drive the tunnel construction vehicle to the location in the tunnel where the coating will be applied;

[0045] Step 2. Control the radial telescopic arm 200 to drive the adjustable dual-head spraying mechanism 400 to move toward the tunnel wall to a predetermined distance;

[0046] Step 3. Start the mortar pump to pump the mortar in the mortar mixing tank into the adjustable double-head spraying mechanism 400, and then spray it onto the tunnel perimeter wall by the adjustable double-head spraying mechanism 400.

[0047] Step 4. During the shotcreting operation in step 3, control the traveling component to move on the adapter 100, so that it drives the adjustable double-head spraying mechanism 400 to move circumferentially along the tunnel wall. The adjustable double-head spraying mechanism 400 moves from one side of the tunnel wall to the other side.

[0048] Step 5. During the spraying process, the wet elastic roller pressing mechanism 500 performs wet roller pressing on the surface formed by spraying with water.

[0049] Step 6. When the adjustable dual-head spraying mechanism 400 moves from one side of the tunnel wall to the other side, the tunnel construction vehicle is erected and moves forward a predetermined distance; then the traveling parts are controlled to move in the opposite direction on the adapter frame 100, and the spraying operation is carried out synchronously.

[0050] Step 7. Repeat steps 1-6 to continuously spray the surface around the tunnel.

[0051] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A mortar spraying device for use on the inner wall of a tunnel, characterized in that: It includes a detachable adapter frame that can be installed on a tunnel construction vehicle, a traveling member that can travel along the arc shape of the tunnel is installed on the adapter frame, a radial telescopic arm is installed on the traveling member, an adjustable double-head spraying mechanism is connected to the radial telescopic arm through a sliding seat, a longitudinal drive mechanism is installed between the adjustable double-head spraying mechanism and the sliding seat, and a wet elastic roller pressing mechanism is installed on the adjustable double-head spraying mechanism. The adapter frame includes an adapter seat that is detachably connected to the arched guide rail, and the adapter seat is detachably connected to the tunnel construction vehicle; the traveling component is a moving slide, which is assembled on the arched guide rail and moves along the arched guide rail; The sliding seat includes a seat body detachably connected to a radial telescopic arm, and a longitudinal slide rail extending along the tunnel length direction is constructed on the seat body. The adjustable double-head spraying mechanism is slidably assembled on the longitudinal slide rail. The longitudinal drive mechanism includes a drive motor mounted on a base, and a longitudinal lead screw coaxially connected to the output shaft of the drive motor. The longitudinal lead screw is threadedly connected to the lower part of the adjustable double-head spraying mechanism. The adjustable dual-head spraying mechanism includes a spraying shell with symmetrical sliding strips on both sides of the lower part. The spraying shell is slidably connected to a longitudinal slide rail via the two sliding strips. A spraying cavity is formed inside the spraying shell. Two spray nozzles arranged in a V-shape are constructed at one end of the spraying shell near the tunnel perimeter wall. A slurry inlet communicating with the spraying cavity is opened on the spraying shell. The slurry delivery pipe is connected to the spraying cavity through the slurry inlet. A slurry adjusting component is provided inside the spraying chamber and between the inlet ends of the two spray nozzles. A connecting shaft with its axis is constructed at both ends of the slurry adjusting component. The two connecting shafts are rotatably connected to the two opposite end walls of the spraying shell. One of the connecting shafts is connected to the spraying shell through an angle adjusting component. A plate-shaped partition gate is movably connected at one end of the spraying shell near the tunnel perimeter wall and between the two spray nozzles. The end of the plate-shaped partition gate that extends into the spraying chamber elastically abuts against the outer surface of the slurry adjusting component.

2. The mortar spraying device for tunnel inner walls according to claim 1, characterized in that: The angle adjustment assembly includes a power motor mounted on the spray shell, a first synchronous pulley coaxially mounted on the output shaft of the power motor, and a second synchronous pulley coaxially mounted on a corresponding connecting shaft. The first and second synchronous pulleys are connected by a synchronous transmission belt.

3. The mortar spraying device for tunnel inner walls according to claim 2, characterized in that: The slurry adjusting component is a hollow elastic rubber material structure with an elliptical cross-section. A connecting shaft has a channel communicating with the inner cavity of the slurry adjusting component. A medium connecting pipe is rotatably connected to the connecting shaft, and the medium connecting pipe communicates with the inner cavity of the slurry adjusting component through the channel.

4. The mortar spraying device for tunnel inner walls according to claim 1, characterized in that: The wet elastic roller pressing mechanism includes two wet rollers arranged side by side. The circumference of each wet roller is covered with seepage holes that communicate with the inner cavity of the wet roller. A seepage layer is provided on the outer circumference of the wet roller. A connecting rod is coaxially constructed at both ends of each wet roller. Each connecting rod is rotatably connected to an elastic telescopic rod, and the elastic telescopic rod is fixed to the spray shell through a connecting plate. The connecting rods on the same side of the two wet rollers are rotatably connected to both ends of a connecting pipe. A connector pipe is installed on the connecting pipe, and a solenoid valve is installed at each of the two ends of the connecting pipe.

5. A method for applying a mortar spraying device to the inner wall of a tunnel as described in any one of claims 1-4, characterized in that, Includes the following steps: Step 1. Drive the tunnel construction vehicle to the location in the tunnel where the coating will be applied; Step 2. Control the radial telescopic arm to drive the adjustable dual-head spraying mechanism to move toward the tunnel wall to a predetermined distance; Step 3. Start the mortar pump to pump the mortar in the mortar mixing tank into the adjustable double-head spraying mechanism, and then spray it onto the tunnel wall by the adjustable double-head spraying mechanism. Step 4. During the shotcreting operation in Step 3, control the traveling component to move on the adapter frame, so that it drives the adjustable double-head spraying mechanism to move circumferentially along the tunnel wall. The adjustable double-head spraying mechanism moves from one side of the tunnel wall to the other side. Step 5. During the spraying process, the wet elastic roller pressing mechanism performs wet roller pressing on the surface formed by spraying with water. Step 6. When the adjustable dual-head spraying mechanism moves from one side of the tunnel wall to the other, the tunnel construction vehicle is erected and moves forward a predetermined distance; then the traveling parts are controlled to move in the opposite direction on the adapter frame to carry out the spraying operation synchronously. Step 7. Repeat steps 1-6 to continuously spray the tunnel perimeter.

Images