Device and method for monitoring deformation and supporting after excavation of soft rock tunnel

Abstract

The present invention relates to the technical field of tunnel excavation, and discloses a device and method for monitoring deformation and support after soft rock tunnel excavation, including a fixed pipe, a target, an insertion rod and a plurality of pressure sensors. It further includes a ground base. The insertion rod is sleeved in the fixed pipe and fixedly connected with a pin. A fixing mechanism is arranged in the fixed pipe, and the fixing mechanism is connected with the pin. The fixing mechanism is used to connect the insertion rod during measurement, and quickly install the pressure sensor and the target at the marked positions in the tunnel. The device and method for monitoring deformation and support after soft rock tunnel excavation can continuously monitor the deformation and support of the tunnel wall, are convenient to disassemble and assemble, and at the same time can facilitate construction workers to observe the deformation of the tunnel at any time during the construction process.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel excavation, and specifically to a device and method for monitoring deformation and support after soft rock tunnel excavation. Background Art

[0002] With the continuous development of the economy, there are more and more water conservancy projects in our country. As a process of passing through mountains, the construction methods and support parameters of the design support system for water conservancy tunnels are constantly being optimized and improved. With the increase in the excavation cross-section, in areas with extremely complex geological conditions, tunnel construction is also accompanied by huge safety hazards. At the construction site, by doing a good job in advance geological forecasting, accurately mastering the geological information of the tunnel section to be excavated, formulating a reasonable construction plan, grouting in advance at the heading face, strengthening the self-stability of the surrounding rock of the tunnel section to be excavated, strengthening the support parameters of the initial support, densifying the spacing of the advanced large pipe shed and the advanced small pipe shed, using the locked foot pipe instead of the locked foot bolt and increasing the number of roots, adding a transverse support to the lower bench of the steel support to make the steel support form a closed loop, and promptly spraying concrete to seal it, strengthening the density and frequency of the surrounding rock measurement and monitoring, promptly and accurately mastering the deformation of the surrounding rock, ensuring that the construction plan can be adjusted in time in case of large deformation, promptly following up the pouring of the floor and lining concrete, shortening the distance between the heading face and the secondary lining, and eliminating safety hazards as soon as possible.

[0003] At present, when monitoring the deformation and support of the surrounding rock of a tunnel after spraying the initial support concrete, it usually needs to be completed manually. Not only is the workload large, but continuous monitoring cannot be carried out, and it is even more impossible to observe the deformation of the tunnel at any time during the construction process. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a device and method for monitoring deformation and support after soft rock tunnel excavation, which has the advantages of being able to continuously monitor the deformation and support of the tunnel wall, being convenient for disassembly and assembly, and at the same time being convenient for construction workers to observe the deformation of the tunnel at any time during the construction process, etc., and solves the problems that manual operation not only has a large workload, but also cannot continuously monitor, and it is even more impossible to observe the deformation of the tunnel at any time during the construction process.

[0005] To achieve the above object, the present invention provides the following technical solution: A device for monitoring deformation and support after excavation of a soft rock tunnel, including a fixed pipe, a target, a plug rod and a plurality of pressure sensors, further including a ground base, characterized in that the plug rod is sleeved in the fixed pipe and fixedly connected with the plug pin, a fixing mechanism is arranged in the fixed pipe, and the fixing mechanism is connected with the plug pin, and the fixing mechanism is used to connect the plug rod during measurement, and quickly install the pressure sensor and the target at the marked position in the tunnel; A fixing ring and a positioning ring are sleeved on the rod wall of the plug rod, an indicating mechanism is jointly connected between the fixing ring and the positioning ring, the target is connected with the indicating mechanism, and the indicating mechanism cooperates with the target to display the position after the device is installed, and is used to observe the deformation of the tunnel wall in real time during the construction process; A circular ring is connected to the rod wall of the plug rod, a plurality of transmission rods are movably connected to the edge of the circular ring, a plugging portion is arranged at one end of the transmission rod, and the other end of the transmission rod is connected with the pressure sensor.

[0006] Preferably, the fixing mechanism includes a positioning pipe and a sleeve, the positioning pipe and the sleeve are both fixed in the fixed pipe, arc-shaped notches are respectively arranged at opposite ends of the positioning pipe and the sleeve, and the two arc-shaped notches together form a clamping groove with a wavy structure. Two through holes are symmetrically arranged on the pipe wall of the sleeve, and both through holes communicate with the arc-shaped notch at the upper end of the sleeve. A shell is sleeved on the rod wall of the plug rod, and the shell is sleeved with the inner wall of the fixed pipe. A first spring and a limiting ring are sleeved in the shell, the limiting ring is fixedly connected with the rod wall of the plug rod, one end of the first spring is fixedly connected with the limiting ring, and the other end of the first spring is fixedly connected with the inner wall of the shell; inclined surfaces are arranged between the two through holes and the lower end of the sleeve, and the two inclined surfaces are symmetrically arranged.

[0007] Preferably, the indicating mechanism includes a pointer, one end of the pointer is fixedly connected with a guide rod, one end of the guide rod is fixedly connected with the positioning ring, two guide sleeves are fixedly connected to the side wall of the fixing ring, guide rods are sleeved in both guide sleeves, and a plurality of uniformly distributed positioning blocks are fixedly connected to the side wall of the positioning ring. Two of the positioning blocks are respectively fixedly connected with one ends of the two guide rods. One side of the positioning block is rotatably connected with a pull rod through a connecting shaft. A connecting portion is arranged at one end of the pull rod, the pull rod is fixedly connected with a positioning shaft through the connecting portion, a C-shaped block is clamped on the shaft wall of the positioning shaft, and the C-shaped block is fixedly connected with the rod wall of the transmission rod; A positioning bolt is threadedly connected to the side wall of the fixing ring through a first threaded hole, a second spring is sleeved on the rod wall of the guide rod, one end of the second spring is fixedly connected with the guide sleeve, and the other end of the second spring is fixedly connected with the positioning block.

[0008] Preferably, a horizontal pipe is provided on one side of the circular ring. Two limiting strips are symmetrically provided at one end of the horizontal pipe. An elastic part is fixedly connected between the two limiting strips. A plurality of annular grooves are evenly distributed on the rod wall of the insertion rod. One of the annular grooves is clamped with the two limiting strips. Raised parts are provided on the inner side walls of the two limiting strips. Pressing parts are provided at one ends of the two limiting strips away from the raised parts.

[0009] Preferably, a plurality of evenly distributed insertion slots are formed at the edge of the circular ring. The plurality of transmission rods are symmetrically inserted into the insertion slots formed at the edge of the circular ring through the insertion parts. A plurality of bolts are threadedly connected to one side of the circular ring through second threaded holes. The insertion parts are fixed by the bolts. One end of the transmission rod away from the insertion part is rotatably connected to a fixing plate through a rotating shaft. The pressure sensor is installed on one side of the fixing plate.

[0010] Preferably, a sleeve is sleeved on the rod wall of the insertion rod, and limiting rings are provided at both ends of the sleeve. Both limiting rings are fixedly connected to the rod wall of the insertion rod. One side of the circular ring is in contact with one of the limiting rings.

[0011] The present invention also provides an operation method for a device for monitoring deformation and support after soft rock tunnel excavation, including the following steps:

[0012] Step 1: After the tunnel is excavated, drill holes at appropriate positions in the tunnel to install fixed pipes and grout for fixation;

[0013] Step 2: After the primary support concrete is sprayed on the tunnel wall, insert the insertion rod into the fixed pipe to install the pressure sensor;

[0014] Step 3: Install a target on the insertion rod and paste a target paper;

[0015] Step 4: Install a ground base on the roadbed surface in the tunnel.

[0016] Preferably, when installing the pressure sensor in Step 2, select the installation quantity of the pressure sensor and the transmission rod according to the installation position of the fixed pipe.

[0017] Preferably, when installing the target in Step 3, select a pull rod to connect the positioning ring and the transmission rod at any position. Before fixing the fixed ring with the positioning bolt, adjust the fixed ring so that the center point of the target paper on the target is aligned with the pointer.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. When the present invention is in use, a suitable position is selected in the excavated tunnel to drill and install a fixed pipe, and grouting is carried out for fixation. After the sprayed primary support concrete is dried, the insertion rod is inserted into the fixed pipe and fixed by the fixing mechanism. The pressure sensor is attached to the inner wall of the tunnel and maintains a certain pressure. At this time, the electronic monitoring component for monitoring deformation and the support device is completed. Then, the indicating mechanism is installed on the insertion rod and connected to the transmission rod at the corresponding position. At this time, the installation of the mechanical monitoring component indicating mechanism is completed, and the deformation of the tunnel wall can be observed at any time during the construction process.

[0020] 2. The fixing mechanism provided by the present invention, when in use, utilizes the positioning pipe and the sleeve to form a wavy clamping groove, which can quickly disassemble and assemble the insertion rod without the need for additional fixing means, facilitating the use by technicians.

[0021] 3. The indicating mechanism provided by the present invention, when the tunnel wall deforms and squeezes the pressure sensor, the fixing plate is stressed and squeezes the transmission rod to deform and generate displacement. When the transmission rod deforms, it drives the C-shaped block to squeeze the positioning shaft. The positioning shaft is stressed to push the pull rod, causing the positioning ring to be stressed. The positioning ring slides on the insertion rod, and the sliding of the positioning ring drives the guide rod to move the pointer. When the pointer moves, the position between the pointer and the target is changed, so that the deformation of the tunnel wall can be conveniently observed at any time during the construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic structural diagram of a device for monitoring deformation and support after soft rock tunnel excavation proposed by the present invention;

[0023] Figure 2 is a schematic structural diagram of the indicating mechanism in a device for monitoring deformation and support after soft rock tunnel excavation proposed by the present invention;

[0024] Figure 3 is a schematic structural diagram of the transmission rod in a device for monitoring deformation and support after soft rock tunnel excavation proposed by the present invention;

[0025] Figure 4 is a schematic structural diagram of the pull rod in a device for monitoring deformation and support after soft rock tunnel excavation proposed by the present invention;

[0026] Figure 5 is a schematic structural diagram of the fixing mechanism in a device for monitoring deformation and support after soft rock tunnel excavation proposed by the present invention;

[0027] Figure 6 is the working principle of the fixing mechanism in a device for monitoring deformation and support after soft rock tunnel excavation proposed by the present invention Figure 1 ;

[0028] Figure 7The working principle of the fixing mechanism in a device for monitoring deformation and support after excavation of soft rock tunnels proposed by the present invention Figure 2 ;

[0029] Figure 8 The working principle of the fixing mechanism in a device for monitoring deformation and support after excavation of soft rock tunnels proposed by the present invention Figure 3 ;

[0030] Figure 9 The working principle of the fixing mechanism in a device for monitoring deformation and support after excavation of soft rock tunnels proposed by the present invention Figure 4 ;

[0031] Figure 10 A device for monitoring deformation and support after excavation of soft rock tunnels proposed by the present invention Figure 1 The enlarged view of the structure at A in it;

[0032] Figure 11 The structural schematic diagram of the insertion rod and the sleeve in a device for monitoring deformation and support after excavation of soft rock tunnels proposed by the present invention;

[0033] Figure 12 The structural schematic diagram of the circular ring in a device for monitoring deformation and support after excavation of soft rock tunnels proposed by the present invention;

[0034] Figure 13 The structural schematic diagram of the limiting strip and the elastic part in a device for monitoring deformation and support after excavation of soft rock tunnels proposed by the present invention;

[0035] Figure 14 The construction effect diagram of a device for monitoring deformation and support after excavation of soft rock tunnels proposed by the present invention.

[0036] In the figure: 1, fixed pipe; 2, insertion rod; 3, sleeve; 4, transmission rod; 5, C-shaped block; 6, pull rod; 7, positioning ring; 8, fixed ring; 9, target; 10, pointer; 11, guide rod; 12, fixed plate; 13, annular groove; 14, positioning block; 15, guide rod; 16, second spring; 17, guide sleeve; 18, pressure sensor; 19, insertion part; 20, positioning shaft; 21, first spring; 22, limiting ring; 23, sleeve; 24, arc-shaped notch; 25, positioning pipe; 26, through hole; 27, pin; 28, housing; 29, limiting ring; 30, bolt; 31, horizontal pipe; 32, slot; 33, circular ring; 34, limiting strip; 35, protruding part; 36, elastic part. Specific embodiments

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0038] Embodiment 1:

[0039] Referring to the attached Figure 1-13 , a device for monitoring the deformation and support after the excavation of a soft rock tunnel includes a fixed pipe 1, a target 9, an insertion rod 2, and a plurality of pressure sensors 18. It also includes a ground base installed on the roadbed in the tunnel. The insertion rod 2 is sleeved in the fixed pipe 1 and fixedly connected with a pin 27. A fixing mechanism is provided in the fixed pipe 1 and is connected to the pin 27. The fixing mechanism is used to connect the insertion rod 2 during measurement, quickly install the pressure sensors 18 and the target 9 at the marked positions in the tunnel. A fixing ring 8 and a positioning ring 7 are sleeved on the rod wall of the insertion rod 2. An indicating mechanism is commonly connected between the fixing ring 8 and the positioning ring 7. The target 9 is connected to the indicating mechanism. The indicating mechanism cooperates with the target 9 to display the initial position after the installation of the device, and is used to observe the deformation of the tunnel wall in real time during the construction process.

[0040] A circular ring 33 is connected to the rod wall of the insertion rod 2. A plurality of transmission rods 4 are movably connected to the edge of the circular ring 33. One end of each transmission rod 4 is provided with a plugging portion 19, and the other end of the transmission rod 4 is connected to the pressure sensor 18. A plurality of uniformly distributed slots 32 are formed in the edge of the circular ring 33. The plurality of transmission rods 4 are symmetrically plugged into the edge of the circular ring 33 through the plugging portions 19. A plurality of bolts 30 are threadedly connected to one side of the circular ring 33 through second threaded holes. One end of the transmission rod 4 away from the plugging portion 19 is rotatably connected to a fixing plate 12 through a rotating shaft. The pressure sensor 18 is installed on one side of the fixing plate 12. A transverse pipe 31 is provided on one side of the circular ring 33. Two limiting strips 34 are symmetrically provided at one end of the transverse pipe 31. An elastic portion 36 is commonly fixed between the two limiting strips 34. A plurality of uniformly distributed annular grooves 13 are provided on the rod wall of the insertion rod 2. One of the annular grooves 13 is clamped with the two limiting strips 34. A convex portion 35 is provided on the side wall of the limiting strip 34. One end of the limiting strip 34 is provided with a pressing portion. A sleeve 3 is sleeved on the rod wall of the insertion rod 2, and limiting rings 29 are provided at both ends of the sleeve 3. Both limiting rings 29 are fixedly connected to the rod wall of the insertion rod 2. One side of the circular ring 33 is in contact with one of the limiting rings 29.

[0041] When the present invention is in use, a suitable position is selected in the excavated tunnel to drill and install the fixing pipe 1, and grouting is carried out for fixation. After the sprayed primary support concrete is dried, the inserting rod 2 is inserted into the fixing pipe 1 and fixed by the fixing mechanism. Then, the transmission rod 4 is inserted into the slot 32 and fixed by bolts 30. Then, the ring 33 is sleeved on the inserting rod 2 so that the pressure sensor 18 contacts the inner wall of the tunnel. The fastening member composed of the limiting strip 34 and the elastic part 36 is used to cooperate with the annular groove 13 to position the ring 33, so that the pressure sensor 18 fits the inner wall of the tunnel and maintains a certain pressure. At this time, the electronic monitoring component for monitoring deformation and the supporting device is completed. Then, the indicating mechanism is installed on the inserting rod 2 and connected to the corresponding transmission rod 4. At this time, the installation of the mechanical monitoring component indicating mechanism is completed, and the deformation of the tunnel wall can be observed at any time during the construction process.

[0042] Embodiment 2: Different from Embodiment 1;

[0043] Refer to the attached Figure 5-10 , the fixing mechanism includes a positioning pipe 25 and a sleeve 23. The positioning pipe 25 and the sleeve 23 are both fixed in the fixing pipe 1. Continuous arc-shaped notches 24 are provided at opposite ends of the positioning pipe 25 and the sleeve 23. The two arc-shaped notches 24 together form a clamping groove with a wavy structure. Two through holes 26 are symmetrically provided on the pipe wall of the sleeve 23, and both through holes 26 communicate with the arc-shaped notch 24 at the upper end of the sleeve 23. A housing 28 is sleeved on the rod wall of the inserting rod 2, and the housing 28 is sleeved with the inner wall of the fixing pipe 1. A first spring 21 and a limiting ring 22 are sleeved in the housing 28. The limiting ring 22 is fixedly connected to the rod wall of the inserting rod 2. One end of the first spring 21 is fixedly connected to the limiting ring 22, and the other end of the first spring 21 is fixedly connected to the inner wall of the housing 28. Inclined planes are provided between the two through holes 26 and the lower end of the sleeve 23, and the two inclined planes are symmetrically arranged.

[0044] For the fixing mechanism provided by the present invention, when in use, hold the sleeve 3 by hand and insert the inserting rod 2 into the fixing pipe 1. At this time, the housing 28 on the inserting rod 2 contacts the sleeve 23 and stops advancing. At this time, the inserting rod 2 drives the limiting ring 22 to compress the first spring 21 and contract, so that the inserting rod 2 continues to advance. The pin 27 on the inserting rod 2 first contacts the inclined plane on the sleeve 23. Restricted by the inclined plane, the pin 27 drives the inserting rod 2 to rotate. After rotation, the pin 27 slides into the through hole 26 and enters the clamping groove (as Figure 5 shown). When the pin 27 contacts the arc-shaped notch 24 on the positioning pipe 25, restricted by the arc-shaped notch 24, the pin 27 continues to rotate and is clamped in the clamping groove (as Figure 6 shown), and the inserting rod 2 cannot continue to advance. At this time, release the sleeve 3 by hand, and the elastic force of the first spring 21 reversely pushes the limiting ring 22 to move the inserting rod 2. After the inserting rod 2 moves, it drives the pin 27 to move into the arc-shaped notch 24 on the sleeve 23 (asFigure 7 As shown in the figure, at this time, the plug rod 2 can be fixed by the cooperation of the bolt 27 and the clamping groove. When disassembling the plug rod 2, directly hold the sleeve 3 and push the plug rod 2 to move the bolt 27 into the arc-shaped notch 24 on the positioning tube 25 (as Figure 8 shown), then release the sleeve 3 by hand. Under the elastic force of the first spring 21, the rebounding force pushes the plug rod 2 to move the bolt 27 into the through hole 26 (as Figure 9 shown). At this time, the bolt 27 on the plug rod 2 disengages from the plugging groove to release the fixation of the plug rod 2.

[0045] Embodiment 3: Different from Embodiment 1;

[0046] Referring to the appendix Figure 1-4 , the indicating mechanism includes a pointer 10. One end of the pointer 10 is fixedly connected with a guide rod 11. One end of the guide rod 11 is fixedly connected with the positioning ring 7. Two guide sleeves 17 are fixedly connected to the side wall of the fixed ring 8. Guide rods 15 are sleeved in both of the two guide sleeves 17. A plurality of uniformly distributed positioning blocks 14 are fixedly connected to the side wall of the positioning ring 7. Two of the positioning blocks 14 are respectively fixedly connected with one end of the two guide rods 15. One side of the positioning block 14 is rotatably connected with a pull rod 6 through a connecting shaft. A connecting portion is provided at one end of the pull rod 6. The pull rod 6 is fixedly connected with a positioning shaft 20 through the connecting portion. A C-shaped block 5 is clamped on the shaft wall of the positioning shaft 20. The C-shaped block 5 is fixedly connected with the rod wall of the transmission rod 4.

[0047] A positioning bolt is threadedly connected to the side wall of the fixed ring 8 through a first threaded hole. A second spring 16 is sleeved on the rod wall of the guide rod 15. One end of the second spring 16 is fixedly connected with the guide sleeve 17. The other end of the second spring 16 is fixedly connected with the positioning block 14.

[0048] In the indicating mechanism provided by the present invention, when the tunnel wall deforms and squeezes the pressure sensor 18, the fixing plate 12 is stressed and squeezed to deform the transmission rod 4 to generate displacement. When the transmission rod 4 deforms, it drives the C-shaped block 5 to squeeze the positioning shaft 20. The positioning shaft 20 is stressed to push the pull rod 6 to stress the positioning ring 7. The positioning ring 7 slides on the plug rod 2 under stress. The positioning ring 7 drives the guide rod 11 to move the pointer 10. When the pointer 10 moves, the position between the pointer 10 and the target 9 is changed. Thus, it is convenient to observe the deformation condition of the tunnel wall at any time during construction.

[0049] Embodiment 4:

[0050] Referring to Figure 14 , the present invention also provides an operation method for the soft rock tunnel rock excavation post-monitoring deformation and support device as follows:

[0051] 1. After the tunnel excavation, drill holes at appropriate positions in the tunnel to install the fixed pipe 1 and grout it for fixation. The position for installing the fixed pipe 1 is preferably at the position of the originally designed support anchor rod, and a certain length is reserved, which exceeds the thickness of the tunnel lining. When grouting, keep the fixed pipe 1 inserted into the deepest part of the hole to prevent mortar from seeping into the fixed pipe 1, and seal the reserved end nozzle of the fixed pipe 1 before spraying the primary support concrete;

[0052] 2. After spraying the primary support concrete on the tunnel wall, insert the insertion rod 2 into the fixed pipe 1 to install the pressure sensor 18. When installing the pressure sensor 18, select the installation quantity of the pressure sensor 18 and the transmission rod 4 according to the installation position of the fixed pipe 1. After fixation, connect the data cable of the pressure sensor 18 and label the pressure sensor 18. Record the value of the pressure sensor 18 as the initial pressure parameter. The change of the pressure parameter represents the deformation of the tunnel inner wall;

[0053] 3. Install the target 9 on the insertion rod 2 and paste the target paper. When installing the target 9, select a pull rod 6 to connect the positioning ring 7 and the transmission rod 4 at any position. Before fixing the fixed ring 8 with the positioning bolt, adjust the fixed ring 8 so that the center point of the target paper on the target 9 is aligned with the pointer 10. Under normal conditions, the transmission rod 4, the pull rod 6 and the positioning ring 7 all remain stationary on the insertion rod 2, that is, the position of the pointer 10 on the target paper remains unchanged. When the tunnel inner wall deforms, under the action of the pull rod 6, the pointer 10 deviates from the target paper, playing a role of observing at any time during the construction process.

[0054] 4. Install the ground base on the roadbed surface in the tunnel. The ground base is used to install engineering surveying instruments. After initially installing the target 9, measure the target 9 and the target paper at each target position, and record the measurement data as the later comparison parameter. When measuring regularly, install the engineering surveying instruments on the ground base again for measurement.

[0055] It should be noted that the term "including" or any other variant thereof is intended to cover non - exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0056] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for monitoring the deformation and support after the excavation of a soft rock tunnel, comprising a fixed pipe (1), a target (9), a plug rod (2) and a plurality of pressure sensors (18), and further comprising a ground base, characterized in that, The insertion rod (2) is sleeved in the fixed pipe (1) and fixedly connected with a bolt (27). A fixing mechanism is arranged in the fixed pipe (1), and the fixing mechanism is connected with the bolt (27). The fixing mechanism is used to connect the insertion rod (2) during measurement, and quickly install the pressure sensor (18) and the target (9) at the marked position in the tunnel. A fixing ring (8) and a positioning ring (7) are sleeved on the rod wall of the insertion rod (2). An indicating mechanism is jointly connected between the fixing ring (8) and the positioning ring (7). The target (9) is connected with the indicating mechanism. The indicating mechanism cooperates with the target (9) to display the position after the device is installed, and is used to observe the deformation of the tunnel wall in real time during the construction process. A ring (33) is connected to the rod wall of the insertion rod (2). A plurality of transmission rods (4) are movably connected to the edge of the ring (33). A plugging portion (19) is arranged at one end of the transmission rod (4), and the other end of the transmission rod (4) is connected with the pressure sensor (18). The fixing mechanism includes a positioning pipe (25) and a sleeve (23). The positioning pipe (25) and the sleeve (23) are both fixed in the fixed pipe (1). Continuously arranged arc-shaped notches (24) are formed at opposite ends of the positioning pipe (25) and the sleeve (23). The two arc-shaped notches (24) jointly form a clamping groove with a wavy structure. Two through holes (26) are symmetrically formed in the pipe wall of the sleeve (23). Both of the two through holes (26) are communicated with the arc-shaped notch (24) at the upper end of the sleeve (23). A housing (28) is sleeved on the rod wall of the insertion rod (2), and the housing (28) is sleeved on the inner wall of the fixed pipe (1). A first spring (21) and a limiting ring (22) are sleeved in the housing (28). The limiting ring (22) is fixedly connected with the rod wall of the insertion rod (2). One end of the first spring (21) is fixedly connected with the limiting ring (22), and the other end of the first spring (21) is fixedly connected with the inner wall of the housing (28).Bevels are provided between the two through holes (26) and the lower end of the sleeve (23), and the two bevels are symmetrically arranged. The indicating mechanism includes a pointer (10), one end of the pointer (10) is fixedly connected to a guide rod (11), one end of the guide rod (11) is fixedly connected to the positioning ring (7), two guide sleeves (17) are fixedly connected to the side wall of the fixing ring (8), guide rods (15) are sleeved in the two guide sleeves (17), a plurality of uniformly distributed positioning blocks (14) are fixedly connected to the side wall of the positioning ring (7), and two of the positioning blocks (14) are respectively fixedly connected to one ends of the two guide rods (15). One side of the positioning block (14) is rotatably connected to a pull rod (6) through a connecting shaft. A connecting portion is provided at one end of the pull rod (6), and the pull rod (6) is fixedly connected to a positioning shaft (20) through the connecting portion. A C-shaped block (5) is clamped on the shaft wall of the positioning shaft (20), and the C-shaped block (5) is fixedly connected to the rod wall of the transmission rod (4); a positioning bolt is threadedly connected to the side wall of the fixing ring (8) through a first threaded hole, a second spring (16) is sleeved on the rod wall of the guide rod (15), one end of the second spring (16) is fixedly connected to the guide sleeve (17), and the other end of the second spring (16) is fixedly connected to the positioning block (14).; 2. The device for monitoring the deformation and support after the excavation of a soft rock tunnel according to claim 1, characterized in that, On one side of the ring (33), there is a horizontal pipe (31). At one end of the horizontal pipe (31), two limiting strips (34) are symmetrically arranged. An elastic part (36) is fixedly connected between the two limiting strips (34). On the rod wall of the insertion rod (2), there are a plurality of uniformly distributed annular grooves (13). One of the annular grooves (13) is clamped with the two limiting strips (34). On the inner side walls of the two limiting strips (34), there are protruding parts (35). At one end of the two limiting strips (34) away from the protruding part (35), there are pressing parts.

3. The device for monitoring the deformation and support after the excavation of a soft rock tunnel according to claim 2, characterized in that, At the edge of the ring (33), a plurality of uniformly distributed slots (32) are opened. The plurality of transmission rods (4) are symmetrically inserted into the slots (32) opened at the edge of the ring (33) through the insertion parts (19). On one side of the ring (33), a plurality of bolts (30) are connected by second threaded holes. The insertion parts (19) are fixed by the bolts (30). At one end of the transmission rod (4) away from the insertion part (19), a fixing plate (12) is rotationally connected through a rotating shaft. The pressure sensor (18) is installed on one side of the fixing plate (12).

4. The device for monitoring deformation and support after excavation of a soft rock tunnel according to claim 1, characterized in that, A sleeve (3) is sleeved on the rod wall of the insertion rod (2). At both ends of the sleeve (3), there are limiting rings (29). Both of the limiting rings (29) are fixedly connected with the rod wall of the insertion rod (2). One side of the ring (33) is in contact with one of the limiting rings (29).

5. An operation method of a device for monitoring deformation and support after excavation of a soft rock tunnel as described in any one of claims 1-4, characterized in that, It includes the following steps: Step 1: After the tunnel is excavated, select a suitable position in the tunnel to drill and install the fixed pipe (1), and grout and fix it. Step 2: After the primary support concrete is sprayed on the tunnel wall, insert the insertion rod (2) into the fixed pipe (1) to install the pressure sensor (18). Step 3: Install a target (9) on the insertion rod (2) and paste a target paper. Step 4: Install a ground base on the roadbed surface in the tunnel.

6. The operation method for monitoring deformation and support after excavation of a soft rock tunnel according to claim 5, characterized in that, When installing the pressure sensor (18) in Step 2, according to the installation position of the fixed pipe (1), select the installation quantity of the pressure sensor (18) and the transmission rod (4).

7. The operation method for monitoring deformation and support after excavation of a soft rock tunnel according to claim 5, characterized in that, When installing the target (9) in Step 3, select a pull rod (6) to connect the positioning ring (7) and the transmission rod (4) at any position. Before fixing the fixed ring (8) with a positioning bolt, adjust the fixed ring (8) so that the center point of the target paper on the target (9) is aligned with the pointer (10).

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