Longitudinal slope shield tunnel multi-angle tunneling simulation test system

Abstract

A longitudinal slope shield tunnel multi-angle tunneling simulation test system disclosed by the present invention comprises a test bench, the test bench is provided with a test box and a shield tunneling model, and the shield tunneling model comprises a shield structure, a tunneling driving mechanism and an angle adjusting mechanism; a mounting hole is formed in one side, close to the shield tunneling model, of the test box, and the shield structure penetrates through the mounting hole and extends into a test soil body; the shield structure comprises a shield segment, the shield segment is sleeved with a shield shell, the front end of the shield shell is detachably connected with a cutterhead, the cutterhead is rotationally arranged relative to the front end of the shield shell, and the cutterhead is connected with the tunneling driving mechanism through a transmission rod; the shield shell is provided with a grouting structure, and the grouting structure is connected with a grouting control device through a grouting outer pipe. And one end, far away from the cutter head, of the shield segment is connected with the mounting hole through a flexible elastic connecting assembly. According to the invention, the whole shield tunneling process of the multi-angle longitudinal slope tunnel is simulated and tested to the greatest extent.

Description

Technical Field

[0001] The invention relates to the technical field of shield tunnel excavation simulation, in particular to a multi-angle excavation simulation test system for a longitudinal slope shield tunnel. Background Art

[0002] The shield method is a fully mechanized construction method for tunnel excavation. Due to the large size of the engineering equipment and the complex working conditions, it is necessary to simulate the shield tunnel process in advance. However, the current simulation equipment is relatively simple in simulating the excavation structure, resulting in a large difference from the actual working conditions. There are excavation processes that cannot simulate the changes in tunnel slope or the simulation structure of the relevant slope changes is relatively complex, which affects the actual effect of the shield excavation simulation test. It is difficult to simulate the entire process of real shield tunnel excavation to the greatest extent. Summary of the invention

[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a multi-angle excavation simulation test system for a longitudinal slope shield tunnel, which simulates the entire shield excavation process of a multi-angle longitudinal slope tunnel to the greatest extent.

[0004] Technical solution: To achieve the above-mentioned purpose, a longitudinal slope shield tunnel multi-angle excavation simulation test system of the present invention comprises a test bench, on which a test box and a shield excavation model are arranged, and the shield excavation model comprises a shield structure, an excavation drive mechanism and an angle adjustment mechanism;

[0005] The angle adjustment mechanism is used to adjust the excavation slope, and the excavation drive mechanism is used to drive the shield structure to excavate along the adjusted excavation slope direction;

[0006] The test box is used to hold the test soil, and a mounting hole is provided on one side of the test box close to the shield excavation model, and the shield structure extends into the test soil through the mounting hole;

[0007] The shield structure comprises a shield segment, a shield shell is sleeved on the outer side of the shield segment, a cutter disc is detachably connected to the front end of the shield shell, the cutter disc is rotatably arranged relative to the front end of the shield shell, and the cutter disc is connected to the excavation drive mechanism through a transmission rod;

[0008] The shield shell is provided with a grouting structure, and the grouting structure is connected to a grouting control device through a grouting outer pipe;

[0009] One end of the shield segment away from the cutterhead is connected to the mounting hole via a soft elastic connecting component.

[0010] Furthermore, the flexible elastic connection assembly includes an elastic rubber ring, one end of which is fixedly connected to the end of the shield segment, and the other end of the elastic rubber ring is fixedly connected to an embedded clamping ring, and the embedded clamping ring is limitedly engaged with the mounting hole; the end of the shield segment is connected to the embedded clamping ring via a hinge.

[0011] Furthermore, the excavation drive mechanism is provided with a cutting motor, and the cutting motor is fixedly connected to one end of the transmission rod; the cutting motor is fixedly connected to a sliding block, and the sliding block is driven by the excavation motor to slide along a slide rail.

[0012] Furthermore, the angle adjustment mechanism is provided with an adjustment platform, the excavation drive mechanism is provided on the adjustment platform, the end of the adjustment platform close to the test box is hinged to the test platform surface, the end of the adjustment platform away from the test box is hinged to the upper end of the lifting plate, and the adjustment platform is provided with an inclinometer.

[0013] Furthermore, the lifting plate is vertically arranged, and the lifting plate is lifted and lowered in contact with the vertical guide sliding surface; a rack structure is arranged on one vertical surface of the lifting plate, and the rack structure is meshed with the lifting drive gear, and the angle detection signal output end of the inclinometer is electrically connected to the drive device control signal receiving end of the lifting drive gear.

[0014] Furthermore, a small-diameter step surface is provided at the front end of the shield shell, and the cutter disc is mounted on the small-diameter step surface. The small-diameter step surface and the inner ring surface of the cutter disc are correspondingly provided with annular grooves. The two annular grooves are spliced ​​inside and outside to form a closed annular groove. A plurality of balls are provided in the closed annular groove to form a bearing structure. The outer diameter of the cutter disc is consistent with the outer diameter of the shield shell.

[0015] Furthermore, a sealing brush is provided at the rear end of the shield shell, and the sealing brush seals the fitting gap between the shield shell and the shield segment.

[0016] Furthermore, the grouting structure includes a plurality of grouting channels arranged inside the shield shell, and the plurality of grouting channels are evenly arranged around the central axis of the shield shell; a grouting pipe is installed in the grouting channel, and the plurality of grouting pipes are connected to the grouting outer pipe; the outlet of the grouting pipe is arranged on the tail end face of the shield shell, and the outlets of the plurality of grouting pipes are arranged around the outside of the sealing brush.

[0017] Further, the following steps are included:

[0018] S1. Select the required cutterhead to assemble the shield structure, extend the shield structure into the test box through the installation hole, and connect it to the test box;

[0019] S2, prepare grouting materials, put them into the grouting control device, connect the grouting outer pipe and set the grouting parameters;

[0020] S3, setting a preset slope adjustment value, the slider and the lifting plate cooperate to make the adjustment platform at a preset angle and lock the lifting plate position, while the shield shell and the cutter disc are at the initial position;

[0021] S4. Set the cutter head speed and excavation rate, start the cutting motor and excavation motor, and simulate shield excavation with the shield structure. During the test, the soil that flows into the shield segment due to cutting is promptly cleared.

[0022] Beneficial effects: A multi-angle excavation simulation test system for a longitudinal slope shield tunnel of the present invention adjusts the excavation slope through an angle adjustment mechanism, so that the shield structure is located in the soil in the direction of the slope to be simulated, and then the shield structure is driven by the excavation drive mechanism to excavate along the adjusted excavation slope direction, including the rotation and cutting of the cutter head, the advancement of the shield shell and the grouting reinforcement of the shield tail, thereby simulating the entire shield excavation process of the multi-angle longitudinal slope tunnel to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the simulation test system of the present invention;

[0024] Figure 2 A schematic structural diagram of an embodiment of a shield tunneling model of the present invention;

[0025] Figure 3 It is a structural schematic diagram of an embodiment of the shield structure and the flexible elastic connection component of the present invention. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings.

[0027] As attached Figure 1-3 The multi-angle excavation simulation test system for a longitudinal slope shield tunnel comprises a test bench 1, on which a test box 2 and a shield excavation model 3 are arranged, and the shield excavation model 3 comprises a shield structure 4, an excavation drive mechanism 5 and an angle adjustment mechanism 6.

[0028] The angle adjustment mechanism 6 is used to adjust the excavation slope, and the excavation drive mechanism 5 is used to drive the shield structure 4 to excavate along the adjusted excavation slope direction.

[0029] The test box 1 is used to hold the test soil. A mounting hole is provided on one side of the test box 1 close to the shield excavation model 3. The shield structure 4 extends into the test soil through the mounting hole. The buried depth of the shield structure in the soil can be adjusted by changing the laying thickness of the soil in the test box.

[0030] The shield structure 4 includes a shield segment 41, a shield shell 42 is mounted on the outer side of the shield segment 41, a cutterhead 43 is detachably connected to the front end of the shield shell 42, the cutterhead 43 is rotatably arranged relative to the front end of the shield shell 42, and the cutterhead 43 is connected to the tunneling drive mechanism 5 through a transmission rod 44. The transmission rod 44 is arranged along the central axis of the cutterhead, and the tunneling drive mechanism 5 drives the transmission rod to rotate and then drives the cutterhead to rotate, and at the same time drives the transmission rod to advance along its own axial direction, and then drives the cutterhead to advance into the soil body, thereby realizing the cutting and tunneling of the soil body, thereby simulating the tunneling process of the actual shield machine to the greatest extent, and the cutterhead can be replaced according to the cutterhead of the shield machine to be simulated, so that the test results are more in line with reality.

[0031] The shield shell 42 is provided with a grouting structure, and the grouting structure is connected to the grouting control device 7 through the grouting outer pipe 46. It can simulate the shield tail grouting reinforcement synchronously during the excavation process. The changes of the soil body during the excavation and grouting reinforcement process can be directly observed and detected, and the actual working conditions can be restored more.

[0032] The end of the shield segment 41 away from the cutterhead 43 is connected to the mounting hole through a flexible elastic connection component 8. On the basis of ensuring that the excavation burial depth remains unchanged, the shield slope can be adjusted at multiple angles to meet the simulation test requirements of the control variables.

[0033] The soft elastic connection component 8 includes an elastic rubber ring 81, one end of which is fixedly connected to the end of the shield segment 41, and the other end of the elastic rubber ring 81 is fixedly connected to an embedded clamping ring, which is limitedly engaged with the mounting hole; the end of the shield segment 41 is connected to the embedded clamping ring via a hinge.

[0034] The embedded clamping ring includes a joint ring 82 and a limiting ring 83, and the joint ring and the limiting ring are screwed together to form an embedded clamping piece with an annular limiting groove on the outer cylindrical surface. The elastic rubber ring 81 is fixedly connected to the large diameter end of the joint ring 82, and the small diameter end of the joint ring 82 is embedded and matched with the mounting hole. The part of the small diameter end of the joint ring 82 extending out of the mounting hole is threadedly matched with the limiting ring 83; the end of the shield segment 41 is connected to the joint ring 82 through a hinge, so that the shield segment 41 can swing longitudinally relative to the joint ring 82, thereby adjusting the longitudinal angle of the shield segment 41.

[0035] Then the shield structure is limited and connected relative to the test box. In addition, the elastic rubber ring can not only adapt to the angle adjustment changes of the shield structure in the test soil, but also block the test soil and the installation hole. Only the soil produced by the cutter head can be discharged from the installation hole by the shield segment, avoiding the collapse of the test soil near the installation port and leaking from the installation hole to affect the simulation effect.

[0036] The excavation drive mechanism 5 is provided with a cutting motor 51, which is fixedly connected to one end of the transmission rod 44, and the transmission rod is concentrically connected to the motor shaft. The cutting motor can control the rotation speed of the cutter head; the cutting motor 51 is fixedly connected to the slider 52, and the slider 52 is driven by the excavation motor 53 to slide along the slide rail 54. Among them, the slider adopts a concave sliding member, which is buckled on the slide rail. A circular track is set between the slide rail and the slider, and a ball is rolled in the track to reduce the friction between the two relative sliding. A limited stopper is set at each end of the slide rail to prevent the slider from leaving the slide rail. The excavation drive gear is installed on the motor shaft of the excavation motor 53. By setting a rack structure on the surface of the slider and meshing with the excavation drive gear, the excavation motor 53 can control the sliding of the slider, and the sliding direction and sliding speed of the slider can be controlled. Then the excavation speed is controlled.

[0037] The sliding block can also be provided with a locking structure, with threaded holes on both sides of the sliding block, and positioning screws are screwed into the threaded holes. After the sliding block moves into place, the screws are tightened so that the screws are pressed against the side walls of the sliding rail, thereby fixing the relative position of the sliding block relative to the sliding rail.

[0038] The angle adjustment mechanism 6 is provided with an adjustment table 61, on which the excavation drive mechanism 5 is provided. The end of the adjustment table 61 close to the test box 2 is hinged to the table top of the test bench 1, and the end of the adjustment table 61 away from the test box 2 is hinged to the upper end of the lifting plate 62. The adjustment table 61 is provided with an angle meter 63. By lifting and lowering the lifting plate, the adjustment table is turned around the hinge seat between it and the test bench, so as to adjust the slope of the adjustment table. The slide rail and the excavation motor are fixedly connected to the table top of the adjustment table, so that the slope of the slide rail changes with the adjustment table. The layout direction of the slide rail is the excavation direction of the shield structure. The transmission rod is always parallel to the table top of the adjustment table, so as to adjust the pitch angle of the shield structure in the soil, so as to realize the simulation of tunnel excavation of multiple longitudinal slopes. The angle adjustment structure is simple and easy to control.

[0039] Preferably, the lifting plate 62 is vertically arranged, and the lifting plate 62 is lifted and lowered in contact with the vertical guide surface. A rack structure is arranged on one side of the vertical surface of the lifting plate 62, and the rack structure is meshed with the lifting drive gear. The angle detection signal output end of the angle meter 63 is electrically connected to the driving device control signal receiving end of the lifting drive gear. The angle meter drives the internal potentiometer to rotate when the adjustment table swings, and adjusts the real-time angle of the adjustment table by outputting the corresponding voltage value. The output electrical signal can be used as a control signal of the angle adjustment motor. After inputting the set angle value, the swing direction of the adjustment table is first calculated according to the current angle and the preset angle, and then the lifting plate is controlled to select lifting or lowering. Through the real-time feedback control of the angle meter, the angle adjustment motor is turned off after reaching the set value. The angle adjustment motor is used to drive the rotation of the lifting drive gear, and its direction and speed can be controlled, thereby realizing the slope adjustment of the adjustment table. A locking structure is also provided between the lifting plate and the vertical guide surface, which is similar to the locking structure between the slider and the slide rail. It is used to lock the position of the upper and lower plates when the lifting plate moves to a specified height, thereby ensuring the stability of the slope during excavation and avoiding slope shaking that affects the simulation effect.

[0040] The front end of the shield shell 42 is provided with a small-diameter step surface, and the cutter disc 43 is mounted on the small-diameter step surface. The small-diameter step surface and the inner ring surface of the cutter disc 43 are provided with ring grooves correspondingly. The two ring grooves are spliced ​​inside and outside to form a closed ring groove. A number of balls are provided in the closed ring groove to form a bearing structure. The outer diameter of the cutter disc 43 is consistent with the outer diameter of the shield shell 42. The connection relationship between the actual cutter disc and the shield shell can be truly simulated, and the friction between the cutter disc and the shield shell can be reduced. When the cutter disc rotates and cuts forward under the action of the transmission rod, it drives the shield shell to slide axially relative to the shield segment.

[0041] A sealing brush 9 is provided at the tail end of the shield shell 42, and the sealing brush 9 seals the fitted gap between the shield shell 42 and the shield segment 41. Otherwise, the external air pressure will press the air into the gap between the segment and the soil through the gap between the segment and the shield shell, affecting the stability of the soil and the subsequent grouting reinforcement effect. It does not conform to the stress conditions of the soil and the grouting environment of the actual working conditions. Adding the sealing brush is more in line with the actual working conditions.

[0042] The grouting structure includes a plurality of grouting channels arranged inside the shield shell 42, and the plurality of grouting channels are evenly arranged around the central axis of the shield shell 42; a grouting pipe 45 is installed in the grouting channel, and the plurality of grouting pipes 45 are connected to the grouting outer pipe 46; the outlet of the grouting pipe 45 is arranged at the tail end face of the shield shell 42, and the outlets of the plurality of grouting pipes 45 are arranged around the outside of the sealing brush 9. The scene of uniform grouting reinforcement in actual excavation can be truly simulated.

[0043] In summary, the integrated shield tunneling process of "cutter head rotation - tool cutting - shield shell advancement - shield tail sealing - grouting reinforcement" can be realized.

[0044] The simulation test method of the longitudinal slope shield tunnel multi-angle excavation simulation test system comprises the following steps:

[0045] S1, select the required cutter head 43 to assemble the shield structure 4, extend the shield structure 4 into the test box 1 through the installation hole, and connect it to the test box 1;

[0046] S2, prepare grouting materials, put them into the grouting control device 7, connect the grouting outer pipe 46 and set the grouting parameters;

[0047] S3. Set the preset slope adjustment value, and the slider 52 and the lifting plate 62 cooperate to make the adjustment platform 61 located at the preset angle and lock the position of the lifting plate 62, while the shield shell 42 and the cutter head 43 are located at the initial positions; because the shield shell will slip to a certain extent relative to the segment due to the hinged relationship between the segment and the test box when the adjustment platform is adjusting the angle, the slider is driven to cooperate at the same time, so that after the angle is adjusted, the cutter head can fit with the end of the segment, so as to obtain sufficient excavation process in subsequent tests, which is convenient for data collection.

[0048] S4, setting the cutter head rotation speed and the excavation rate, starting the cutting motor 51 and the excavation motor 53, and the shield structure 4 simulates shield excavation. During the test, the soil that is cut and poured into the shield segment 41 is promptly cleared.

[0049] On this basis, considering that tunnels with multiple sections of slope changes may occur during actual excavation, the shield segments 41 are set as multiple sections of annular segments, and the spacing between adjacent segment units is set, and the adjacent segments are connected by hinges, so that the two can swing relative to each other in the longitudinal direction. The adjacent segments are also connected by elastic rubber rings to adapt to angle adjustment while isolating the soil and the inner cavity of the segment. The length of each segment can be set to be equal, and the length can be set to be relatively short. When the forward distance of the shield shell does not exceed the length of a single segment, the multiple segments are constrained by the shield shell to maintain a coaxial state. When a segment is separated from the shield shell, the longitudinal angle of excavation can be readjusted. Due to the effect of tail grouting reinforcement, the segment separated from the shield shell is reinforced and fixed in the soil, thereby more realistically simulating the actual excavation conditions.

[0050] Preferably, the shield segment 41 includes two segment units. When simulating the excavation process of a tunnel with multiple slope changes, the tunnel excavation process is simulated in sections, and only two consecutive sections of tunnel excavation with different slopes are simulated each time, focusing on simulating the entire process of changing from one slope to another.

[0051] At the same time, two grouting outer pipes are provided, which are respectively connected to the grouting pipe 45 in the upper half shell of the shield, so that when the tunnel slope changes, the grouting speed and grouting amount turning to the inside are appropriately reduced, and the grouting speed and grouting amount turning to the outside are appropriately increased, so as to ensure that the grouting reinforcement effect at the tunnel corners meets the actual working conditions.

[0052] The slope range of the initial tunnel section of the simulated excavation depends on the radius size of the installation hole and the swing range allowed by the transmission rod 44. The swing range allowed by the transmission rod 44 depends on its rod diameter and the position of its swing axis. Since the transmission rod 44 always maintains a coaxial position relationship with the current shield tail end sleeve pipe segment during the simulated excavation process, the adjustment range of the pitch angle of the two tunnel sections relative to the horizontal direction is different when simulating two tunnel sections in succession. The hinge point position of the first section pipe segment and the joint ring is the position of the swing axis of the transmission rod 44 when adjusting the slope of the first tunnel, and the hinge point between the second section pipe segment and the first section pipe segment is the position of the swing axis of the transmission rod 44 when adjusting the slope of the second section tunnel. The closer the two hinge points are to the installation hole position, the larger the allowable slope adjustment range is, and the maximum adjustable pitch slope of the first tunnel is greater than the maximum adjustable pitch slope of the second tunnel.

[0053] Therefore, the first segment of the pipe is hinged to the joint ring, and the length of the first segment of the pipe is reasonably selected to make the simulation range of the simulation system more consistent with the actual scenario to be simulated.

[0054] According to the analysis of the actual excavation scenario, the change angle of the tunnel slope will not be very large and will be controlled within a certain angle range. Based on the slope change range, the transmission rods and segment units of appropriate sizes are reasonably selected, and the mounting holes of matching sizes are opened, so that the slope adjustment range allowed by the second section of the tunnel is slightly larger than the slope change range required for actual tunnel excavation.

[0055] In the selection of segment length, assuming that the segment unit length is l, the absolute value of the slope of the first section of the tunnel is a, the radius of the installation hole is R, the radius of the transmission rod is d, and the radius of the tunnel turning is r, then l*sina+r <R。

[0056] In terms of the control of the slope adjustment of the second section of the tunnel, the end of the adjustment platform close to the test box is hinged to another lifting plate, which is also controlled by a lifting drive motor, so that the entire adjustment platform can not only adjust the slope, but also the height of the entire excavation drive mechanism can be adjusted to meet the adjustment of the slope of the second section of the tunnel. The two lifting drive motors have an angle meter feedback control to coordinate the action. During the adjustment process, the cutter head cuts in size and moves forward at a constant speed, truly simulating the excavation process of the tunnel where the slope changes.

[0057] If one section of the tunnel is an inclined tunnel, and the second section of the tunnel turns further to a steeper slope, when adjusting the slope of the second section of the tunnel, the two lifting plates descend at the same time, and the lifting plate farther from the test box descends faster.

[0058] If one section of the tunnel is an inclined tunnel, and the second section of the tunnel further turns to a gentler slope, when the slope of the second section of the tunnel is adjusted, the two lifting plates rise at the same time, and the lifting plate farther from the test box rises faster.

[0059] If one section of the tunnel is a steep-angle longitudinal slope tunnel, and the second section of the tunnel further turns to a steeper slope, when the slope of the second section of the tunnel is adjusted, the two lifting plates rise at the same time, and the lifting plate farther from the test box rises faster.

[0060] If one section of the tunnel is a tunnel with a downward-angled longitudinal slope, and the second section of the tunnel further turns to a gentler slope, when the slope of the second section of the tunnel is adjusted, the two lifting plates descend at the same time, and the lifting plate farther from the test box descends faster.

[0061] If one section of the tunnel is a horizontal tunnel and the second section of the tunnel turns to an inclined longitudinal tunnel, when the slope of the second section of the tunnel is adjusted, the two lifting plates descend at the same time, and the lifting plate farther from the test box descends faster.

[0062] If one section of the tunnel is a horizontal tunnel and the second section of the tunnel turns to a steep longitudinal slope tunnel, when the slope of the two sections of the tunnel is adjusted, the two lifting plates rise at the same time, and the lifting plate farther from the test box rises faster.

[0063] Through the coordinated control of the two lifting drive motors, during the entire angle adjustment process, the transmission rod always rotates relative to the hinge axis between the first and second pipe segments. At the same time, the transmission rod also advances at a uniform speed along its own axis, thereby driving the cutter disc to change the cutting direction while continuing to cut and advance, ensuring that the simulation conforms to the actual working conditions.

[0064] Since the bends are connected with elastic rubber rings, in order to further improve the realism of the pressure simulation at the bends, flexible reinforcement ribs are built into the rubber rings to increase the strength, so that the bends can adapt to the bending deformation caused by the slope change, and at the same time make its pressure bearing strength close to that of the segment unit. The circular cross-sectional structure at the bends is maintained by reinforcement ribs to avoid the change of the test soil at the bends failing to truly reflect the change of the soil at the actual tunnel bends.

[0065] The built-in reinforcement ribs can be made of circular steel wire structures. Multiple steel wires are evenly distributed in the rubber ring and arranged axially. One end of the reinforcement rib is fixed relative to the end face of the second segment, and the other end is slidably arranged relative to the rubber ring wall and the plug hole in the first segment wall, so that the steel wire on the inner side of the bend is inserted deeper relative to the plug hole, and the steel wire on the outer side of the bend slides outward relative to the plug hole, thereby achieving the purpose of supporting the annular structure of the rubber ring while conforming to the bend. Maintaining the gap size between the rubber ring and the soil, ensuring the quality of grouting reinforcement, and simulating more in line with actual working conditions.

[0066] The above description is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the above principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A multi-angle excavation simulation test system for a longitudinal slope shield tunnel, characterized in that: The invention comprises a test bench (1), wherein a test box (2) and a shield tunneling model (3) are arranged on the test bench (1), and the shield tunneling model (3) comprises a shield structure (4), a tunneling drive mechanism (5) and an angle adjustment mechanism (6); The angle adjustment mechanism (6) is used to adjust the excavation slope, and the excavation drive mechanism (5) is used to drive the shield structure (4) to excavate along the adjusted excavation slope direction; The test box (1) is used to contain test soil, and a mounting hole is provided on a side of the test box (1) close to the shield tunneling model (3), and the shield structure (4) extends into the test soil through the mounting hole; The shield structure (4) comprises a shield segment (41), a shield shell (42) is sleeved on the outer side of the shield segment (41), a cutter head (43) is detachably connected to the front end of the shield shell (42), the cutter head (43) is rotatably arranged relative to the front end of the shield shell (42), and the cutter head (43) is connected to the excavation drive mechanism (5) via a transmission rod (44); The shield shell (42) is provided with a grouting structure, and the grouting structure is connected to a grouting control device (7) via a grouting outer pipe (46); One end of the shield segment (41) away from the cutterhead (43) is connected to the mounting hole via a soft elastic connection component (8).

2. A longitudinal slope shield tunnel multi-angle excavation simulation test system according to claim 1, characterized in that: The soft elastic connection assembly (8) comprises an elastic rubber ring (81), one end of the elastic rubber ring (81) is fixedly connected to the end of the shield segment (41), and the other end of the elastic rubber ring (81) is fixedly connected to an embedded clamping ring, and the embedded clamping ring is limitedly engaged with the mounting hole; the end of the shield segment (41) is connected to the embedded clamping ring via a hinge.

3. A longitudinal slope shield tunnel multi-angle excavation simulation test system according to claim 2, characterized in that: The excavation drive mechanism (5) is provided with a cutting motor (51), and the cutting motor (51) is fixedly connected to one end of the transmission rod (44); the cutting motor (51) is fixedly connected to a slide block (52), and the slide block (52) is driven by the excavation motor (53) to slide along a slide rail (54).

4. A longitudinal slope shield tunnel multi-angle excavation simulation test system according to claim 3, characterized in that: The angle adjustment mechanism (6) is provided with an adjustment platform (61), on which the excavation drive mechanism (5) is provided, and one end of the adjustment platform (61) close to the test box (2) is hinged to the table top of the test bench (1), and one end of the adjustment platform (61) away from the test box (2) is hinged to the upper end of the lifting plate (62), and the adjustment platform (61) is provided with an inclinometer (63).

5. The multi-angle excavation simulation test system for longitudinal slope shield tunnel according to claim 4 is characterized by: The lifting plate (62) is arranged vertically, and the lifting plate (62) moves up and down in contact with the vertical guide slide surface; A rack structure is provided on a vertical surface of one side of the lifting plate (62), and the rack structure is meshed with the lifting drive gear. The angle detection signal output end of the inclinometer (63) is electrically connected to the drive device control signal receiving end of the lifting drive gear.

6. A longitudinal slope shield tunnel multi-angle excavation simulation test system according to claim 5, characterized in that: The front end of the shield shell (42) is provided with a small-diameter step surface, and the cutter disc (43) is mounted on the small-diameter step surface. The small-diameter step surface and the inner ring surface of the cutter disc (43) are provided with corresponding annular grooves. The two annular grooves are spliced ​​inside and outside to form a closed annular groove. A plurality of balls are provided in the closed annular groove to form a bearing structure. The outer diameter of the cutter disc (43) is consistent with the outer diameter of the shield shell (42).

7. A longitudinal slope shield tunnel multi-angle excavation simulation test system according to claim 6, characterized in that: A sealing brush (9) is provided at the rear end of the shield shell (42), and the sealing brush (9) has a sealing effect on the fitting gap between the shield shell (42) and the shield segment (41).

8. The multi-angle excavation simulation test system for longitudinal slope shield tunnel according to claim 7 is characterized by: The grouting structure comprises a plurality of grouting channels arranged inside the shield shell (42), and the plurality of grouting channels are evenly arranged around the central axis of the shield shell (42); a grouting pipe (45) is installed in the grouting channel, and the plurality of grouting pipes (45) are all connected to the grouting outer pipe (46); the outlet of the grouting pipe (45) is arranged on the rear end face of the shield shell (42), and the outlets of the plurality of grouting pipes (45) are arranged around the outside of the sealing brush (9).

9. A simulation test method for a multi-angle excavation simulation test system for a longitudinal slope shield tunnel according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Select the required cutterhead (43) to assemble the shield structure (4), extend the shield structure (4) into the test box (1) through the mounting hole, and connect it to the test box (1); S2, preparing grouting materials, placing them into the grouting control device (7), connecting the grouting outer pipe (46) and setting the grouting parameters; S3, setting a preset slope adjustment value, the slider (52) and the lifting plate (62) cooperate to make the adjustment platform (61) be located at a preset angle and lock the position of the lifting plate (62), while the shield shell (42) and the cutter disc (43) are located at the initial positions; S4, setting the cutter head rotation speed and the excavation speed, starting the cutting motor (51) and the excavation motor (53), and the shield structure (4) simulating shield excavation. During the test, the soil that is cut and poured into the shield segment (41) is promptly removed.

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