A combined arch support trolley and method for initial support reinforcement of tunnels

Abstract

The present invention discloses a combined arch support trolley and method for initial support reinforcement of tunnels, which is composed of multiple mobile arch support unit bodies spliced together; the arch support unit body includes an arched workbench, a traveling mechanism is arranged at the bottom of the arched workbench, and multiple arc-shaped support beams that are lapped together to form an arched structure are arranged on one side of the top. Each arc-shaped support beam is connected to the arched workbench through a telescopic mechanism; the combined arch support trolley formed by splicing multiple arch support unit bodies includes a retracted moving form and an extended support form. It has a simple structure, is light and easy to carry, is convenient to implement and has strong operability. Through the switching of the two working forms, it can quickly and reliably support and reinforce the deformed sections at any position of the initial support of the tunnel. With the arched workbench provided by the trolley, it is convenient for workers to carry out aerial operations, can greatly improve the working efficiency of the initial support reinforcement construction, shorten the construction period, reduce financial and time investment, and is safe, efficient and practical in operation.

Description

Technical Field

[0001] The present invention relates to a combined arch support trolley and method for initial support reinforcement of tunnels, belonging to the technical field of tunnel construction. Background Art

[0002] As an underground structure, tunnel construction is difficult and the construction risks are prominent. Especially when passing through soft surrounding rocks or poor geological sections, the structural reliability of the initial support of the tunnel cannot be effectively guaranteed. Specifically, when the geological conditions are poor, or due to reasons such as non-standard construction operations, many problems often occur during tunnel construction, such as cracking and deformation of the initial support, settlement deformation, and even intrusion and instability. This seriously threatens construction safety and structural reliability. In response to the above situation, the most commonly used treatment measure in actual construction is to add a temporary arch support inside the initial support to ensure the stability of the initial support during construction, and then carry out construction operations such as radial grouting reinforcement and arch replacement under the protection of the temporary arch support. After the corresponding reinforcement measures can ensure the stability of the initial support, the temporary arch support is removed. As a temporary auxiliary construction measure, the temporary arch support needs to be erected and removed repeatedly, and the construction process is relatively cumbersome. At present, manual operation is mostly used at the construction site, and the time consumed in the erection and removal process is relatively long. In addition, the I-beams used for the temporary arch support are easily damaged during the removal process, and the material utilization rate is low. In addition, considering that the temporary arch support is added under the premise that there are potential safety hazards in the initial support, there is a certain safety hazard in the construction process using the manual construction method due to the possibility of instability and damage of the initial support.

[0003] It can be seen that the existing method of manually constructing the temporary arch support has many problems such as long construction time, low material utilization rate, and relatively large safety hazards for construction personnel. In view of the above considerations, researching a combined arch support trolley that can significantly improve construction efficiency, material utilization rate, and construction safety has become an urgent problem to be solved in the engineering field. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a combined arch support trolley and method for initial support reinforcement of tunnels, which can overcome the deficiencies of the prior art.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A combined arch support trolley for initial support reinforcement of tunnels is composed of multiple mobile arch support unit bodies spliced together; each arch support unit body includes an arched workbench, a traveling mechanism is provided at the bottom of the arched workbench, and multiple arc-shaped support beams that are lapped together to form an arched structure are provided on one side of the top. Each arc-shaped support beam is connected to the arched workbench through a telescopic mechanism.

[0007] The adjacent arch protection unit bodies are detachably connected through telescopic longitudinal connecting members.

[0008] Monitoring and measuring devices are also provided on the arc-shaped support beam of the aforementioned arch protection unit body. The monitoring and measuring devices include earth pressure cells arranged at the top of the arc-shaped support beam and reinforcing bar stress gauges arranged on the inner side of the arc-shaped support beam.

[0009] The aforementioned arched workbench includes a platform frame arranged in multiple layers of steps. On one side of the platform frame, there is a support frame arranged in an arched structure, and mounting seats for fixing the telescopic mechanism are arranged on the support frame; columns are provided at the bottom of the platform frame and the support frame, and the traveling mechanism is arranged at the bottom end of the columns.

[0010] The aforementioned traveling mechanism includes V-shaped inclined leg members located at the bottom of the columns. An enlarged steel backing plate is provided at the bottom end of the V-shaped inclined leg members; and a telescopic support rod and a bearing roller connected thereto are provided in the middle of the V-shaped inclined leg members.

[0011] The aforementioned arc-shaped support beam is arranged in three sections, including an arch arc-shaped steel beam. Side arc-shaped steel beams are symmetrically arranged at both ends of the arch arc-shaped steel beam. Lap joints are provided at the bottom surfaces of both ends of the arch arc-shaped steel beam, and matching lap grooves are provided at the upper ends of the side arc-shaped steel beams, so that the three arc-shaped steel beams are lapped through the grooves in the extended support state, forming a structure that supports each other between the three arc-shaped steel beams.

[0012] A method for initial support reinforcement of a tunnel, which includes the following steps:

[0013] s1. During the normal construction stage of the tunnel, multiple sections of arch protection unit bodies can be connected into a whole through telescopic longitudinal connecting members to form a combined arch protection trolley, which is arranged and reserved at the tail of the upper or middle bench in the tunnel;

[0014] s2. When the initial support shows cracking deformation, settlement deformation, convergence deformation, etc., determine the deformation range of the initial support through measurement means, and conduct a judgment on the deformation of the initial support to judge whether the initial support is slightly cracked or encroaching;

[0015] s3. According to the deformation range, mobilize some or all of the combined arch protection trolleys to quickly move to the initial support deformation section, and switch to the extended support form to carry out support reinforcement for the deformation section;

[0016] s4. If it is judged to be slightly cracked, carry out radial grouting reinforcement operation on the deformed section;

[0017] s4'. If it is judged to be encroaching, adopt the construction plan of replacing the arch one by one until all the encroaching initial supports are completely demolished and rebuilt, and complete the radial grouting reinforcement construction of all sections.

[0018] In the foregoing steps, the initial support stress is monitored by the monitoring and measuring equipment provided on the arc support beam of the arch protection unit body. The deformation pressure of the initial support is detected by the earth pressure cell, and the stress of the arc support beam is detected by the steel bar stress gauge;

[0019] Through monitoring and observation, combined with the detection values of the earth pressure cell and the steel bar stress gauge, the deformation condition of the initial support is judged.

[0020] In the foregoing step s4, if it is judged to be mild cracking deformation, the following operations are carried out:

[0021] S4.1. According to the actual situation, mobilize some or all of the combined arch protection trolleys to quickly move to the initial support deformation section and switch to the expanded support form to ensure safety during construction. At this time, there is no need to suspend the construction of the heading face personnel;

[0022] S4.2. The construction vehicles and construction personnel are in place. The construction personnel can simultaneously carry out radial grouting reinforcement operations on the initial support deformation section on the arched workbenches of multiple arch protection unit bodies. After the grouting is completed and the grout has solidified, the combined arch protection trolley is withdrawn to the tail of the upper or middle bench and waits for the next call.

[0023] In the foregoing step s4', if it is judged to be intrusion deformation, the following operations are carried out:

[0024] S4.1'. Immediately let the workers at the heading face evacuate and suspend the heading face tunneling construction;

[0025] S4.2'. According to the actual situation, mobilize some or all of the combined arch protection trolleys to quickly move to the initial support deformation section and switch to the expanded support form to prevent possible instability failure of the initial support;

[0026] S4.3'. The construction vehicles and construction personnel are in place. The construction personnel use the first arch protection unit body to install inclined grouting small pipes from behind the undeformed I-beam to the initial support intrusion section to grout and reinforce the surrounding rock;

[0027] S4.4'. After the construction of step S4.3' is completed, the first arch protection unit body switches to the retracted moving form, detaches from the subsequent arch protection unit bodies, and returns to the tail of the upper or middle bench. Then the construction vehicles and construction personnel are in place at the second arch protection unit body;

[0028] S4.5'. The construction personnel demolish and reconstruct the initial support that intrudes into the secondary lining limit under the protection of the arch protection trolley and the first cycle inclined grouting pipe. Then, inclined grouting small pipes are installed to carry out secondary grouting reinforcement on the arch replacement section to ensure the subsequent structural reliability of the initial support in this section;

[0029] s4.6’, Construct the second - cycle inclined grouting small pipes from behind the replaced I - beams towards the un - replaced arch section, and grout and reinforce the surrounding rock;

[0030] s4.7’, Repeat steps s4.3’ to s4.6’, and orderly organize the deployment and construction of the combined arch support trolley, construction vehicles and construction personnel. The idle arch support unit bodies are driven back to the tail of the upper or middle bench and connected as a whole, waiting for the next call;

[0031] s4.8’, Adopt the construction plan of replacing the arch section by section until all the encroaching primary supports are removed and rebuilt, and complete the radial grouting reinforcement construction of all sections.

[0032] Compared with the prior art, a combined arch support trolley for tunnel primary support reinforcement disclosed by the present invention is spliced by multiple movable arch support unit bodies; the arch support unit body includes an arched workbench, a traveling mechanism is provided at the bottom of the arched workbench, and on one side of the top, there are multiple arc - shaped support beams lapped together to form an arched structure. Each arc - shaped support beam is connected to the arched workbench through a telescopic mechanism. The combined arch support trolley formed by splicing multiple arch support unit bodies includes a retracted moving form and an extended supporting form. During the tunnel construction project, the combined arch support trolley is in the retracted moving form and placed at the tail of the upper or middle bench arranged in the tunnel for standby, without interfering with the tunnel construction. The middle cavity of the arched workbench is a construction passage, facilitating the passage of staff and construction vehicles; when the primary support deforms, the combined arch support trolley can be quickly moved to the deformed section to form an extended supporting form for deformation support and reinforcement. The present invention also discloses a method for tunnel primary support reinforcement. While reasonably arranging the combined arch support trolley, it judges the deformation of the primary support, and judges whether the primary support is slightly cracked and deformed or encroaching - limit deformed; if it is slightly cracked and deformed, radial grouting reinforcement operations are carried out on the deformed section; if it is encroaching - limit deformed, the construction plan of replacing the arch section by section is adopted until all the encroaching primary supports are removed and rebuilt, and the radial grouting reinforcement construction of all sections is completed.

[0033] The beneficial effects of the present invention are:

[0034] (1) The combined arch support trolley of the present invention can be set in two forms: a retracted moving form and an extended supporting form. It has a simple structure, is light and easy to carry, is convenient to implement and has strong operability. Through the switching of the two working forms, it can quickly and reliably support and reinforce the deformed sections at any position of the tunnel primary support. With the arched workbench provided by the upper trolley, it is convenient for staff to carry out high - altitude operations, can greatly improve the work efficiency of the primary support reinforcement construction, shorten the construction period, reduce financial and time investment, and has strong practicability;

[0035] (2) The support reinforcement of the initial support deformation section can be carried out in a timely manner, preventing and slowing down the possible instability failure of the initial support, effectively reducing the construction risks of tunnel construction personnel, and having high safety;

[0036] (3) The combined arch support trolley described in the present invention is used as a standby support reinforcement device placed in the tunnel and moves forward as the tunnel advances, so as to carry out support reinforcement in a timely manner, effectively solving the problem of low reuse rate of temporary arch support materials;

[0037] (4) The present invention formulates reasonable and efficient reinforcement measures for the initial support deformation section based on the combined arch support trolley, with safe and efficient operation, and can significantly improve the construction efficiency of arch replacement or grouting reinforcement construction of the initial support.

[0038] Other advantages, objectives and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the drawings, where:

[0040] Figure 1 is a schematic structural diagram of the present invention.

[0041] Figure 2 is Figure 1 a schematic structural diagram of the telescopic longitudinal connecting member 5 in

[0042] Figure 3 is Figure 2 a schematic structural diagram of the telescopic longitudinal rod 501 in

[0043] Figure 4 is Figure 1 a schematic structural diagram of the screw hole seat 8 in

[0044] Figure 5 is Figure 1 a schematic structural diagram of the card slot structure 9 in

[0045] Figure 6 is Figure 1 a schematic structural diagram of the arch support unit body in

[0046] Figure 7 is Figure 6 a schematic structural diagram of the arched workbench 1 in

[0047] Figure 8 is Figure 6Schematic diagram of the support frame 102.

[0048] Figure 9 For Figure 8 Partial enlarged schematic diagram of part A in

[0049] Figure 10 For Figure 8 Partial enlarged schematic diagram of part B in

[0050] Figure 11 For Figure 8 Partial enlarged schematic diagram of part C in

[0051] Figure 12 Figure 1 Schematic diagram of the structure of the backing plate 10 in

[0052] Figure 13 Schematic diagram of the working state of the arched working table 1 in the tunnel.

[0053] Figure 14 Schematic diagram of the structure of the arch protection unit body in the tunnel in the retracted and moving state.

[0054] Figure 15 Schematic diagram of the structure of the arch protection unit body in the tunnel in the expanded and supported state.

[0055] Figure 16 Construction flow chart when the initial support has minor cracking and deformation.

[0056] Figure 17 Construction process when the initial support has intrusion deformation Figure 1 .

[0057] Figure 18 Construction process when the initial support has intrusion deformation Figure 2 .

[0058] Figure 19 Construction process when the initial support has intrusion deformation Figure 3 .

[0059] Figure 20 Construction process when the initial support has intrusion deformation Figure 4 .

[0060] Figure 21 Construction process when the initial support has intrusion deformation Figure 5 . Detailed implementation manner

[0061] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the protection scope of the present invention.

[0062] Such asFigures 1 - 12 As shown in the figure, a combined arch support trolley for the initial support reinforcement of a tunnel is composed of multiple mobile arch support unit bodies spliced together; each arch support unit body includes an arched workbench 1, a traveling mechanism 2 is arranged at the bottom of the arched workbench 1, and on one side of the top, there are multiple arc-shaped support beams 3 lapped together to form an arched structure. Each arc-shaped support beam 3 is connected to the arched workbench 1 through a telescopic mechanism 4.

[0063] See Figures 2 - 5 , adjacent arch support unit bodies are detachably connected through a telescopic longitudinal connecting member 5. On the front and back sides of the arch support unit body, there are corresponding screw hole seats 8 and groove structures 9 respectively, so that one of the adjacent two arch support unit bodies is hinged to the telescopic longitudinal connecting member 5 by bolts, and the other is snap-connected to the telescopic longitudinal connecting member 5. Preferably, a connecting beam 6 is arranged on the arch support unit body, the screw hole seat 8 is arranged at one end of the connecting beam 6, and the groove structure 9 is arranged at the other end of the connecting beam 6.

[0064] Specifically, the telescopic longitudinal connecting member 5 includes a telescopic longitudinal rod 501. One end of the telescopic longitudinal rod 501 is provided with a bolt connecting part 502, and the other end is provided with an L-shaped clamping block 503, so that one of the adjacent two arch support unit bodies is hinged to the telescopic longitudinal connecting member 5 through the bolt connecting part 502, and the other is snap-connected to the telescopic longitudinal connecting member 5 through the L-shaped clamping block 503. The telescopic longitudinal rod 501 can be a hydraulic / electric jack mechanism, an electric hydraulic push rod mechanism or a hydraulic cylinder. Through the telescopic longitudinal connecting member 5, multiple arch support unit bodies can be connected into an integral whole to form a combined arch support trolley for collaborative work, and the longitudinal distance between multiple arch support unit bodies can be adjusted through the telescopic longitudinal rod 501, with a wide range of applications.

[0065] Monitoring and measuring equipment 7 is also arranged on the arc-shaped support beam 3 of the arch support unit body. The monitoring and measuring equipment 7 includes an earth pressure cell 701 arranged on the top of the arc-shaped support beam 3 and a reinforcing bar stress gauge 702 arranged on the inner side of the arc-shaped support beam 3.

[0066] See Figure 6 , the arched workbench 1 includes a platform frame 101 arranged in multiple layers of steps. On one side of the platform frame 101, there is a support frame 102 arranged in an arched structure, and mounting seats 103 for fixing the telescopic mechanism 4 are arranged on the support frame 102; columns 104 are arranged at the bottom of the platform frame 101 and the support frame 102, and the traveling mechanism 2 is arranged at the bottom end of the columns 104.

[0067] Preferably, the platform frame 101 and the support frame 102 can also be designed as a detachable connection structure, which has good flexibility in use. When used alone, the platform frame 101 can be used for high-altitude operations, and the support frame 102 combined with the arc support beam 3 can be used for the protective support of the initial support deformation of the tunnel; while when used in combination, high-altitude operations and protective support can be achieved simultaneously.

[0068] See Figures 7 - 13 , both the platform frame 101 and the support frame 102 are truss structures. Specifically, the platform frame 101 includes an upper-step platform frame 1011, and diagonal braces 1012 are symmetrically arranged at both ends of the upper-step platform frame 1011. A middle-step platform frame 1013 and a lower-step platform frame 1014 are respectively arranged in the middle and at the bottom of the diagonal braces 1012; the support frame 102 includes a support truss 1021 arranged at the rear side of the upper-step platform frame 1011, and upper diagonal braces 1022 are symmetrically arranged at both ends of the support truss 1021; there are four columns 104, the top ends of the columns are fixedly connected to the middle-step platform frame 1013 and the bottom ends of the upper diagonal braces 1022, and the bottom ends are supported on the ground through the traveling mechanism 2. The mounting seat of the telescopic mechanism includes a wedge-shaped triangular cushion block 1031 arranged on the upper surface of the upper diagonal brace 1022, and a horizontal pipe seat 1032 arranged on the column 104, and the horizontal pipe seat 1032 is located at the rear side of the lower-step platform frame 1014.

[0069] The upper-step platform frame 1011 is an eye-shaped frame structure, the diagonal braces 1012, the middle-step platform frame 1013 and the lower-step platform frame 1014 are rectangular frame structures; while the support frame 102 is a triangular frame structure.

[0070] A tread plate 10 for easy stepping is laid on the platform frame 101, and a ladder 11 is arranged on the side, which is convenient for the staff to carry out high-altitude operations on the platform frame 101. Preferably, the tread plate 10 is laid on the upper-step platform frame 1011, the middle-step platform frame 1013 and the lower-step platform frame 1014. The tread plate 10 is a wire mesh plate.

[0071] The telescopic mechanism 4 includes a first telescopic mechanism 401 arranged vertically on the surface of the support truss 1021 and the upper section of the upper diagonal brace 1022, and a second telescopic mechanism 402 arranged horizontally on the lower section of the upper diagonal brace 1022 and the column 104. Both the first telescopic mechanism 401 and the second telescopic mechanism 402 are hydraulic / electric jack mechanisms or hydraulic cylinders.

[0072] The walking mechanism 2 includes V-shaped inclined leg members 201 located at the bottom of the vertical column 104. A telescopic support rod 202 and a bearing roller 203 connected thereto are provided in the middle of the V-shaped inclined leg members 201. The telescopic support rod 202 can be a hydraulic / electric jack or a hydraulic cylinder. When the telescopic support rod 202 extends, the bearing roller 203 can be in a state of walking on the ground. On the contrary, when the telescopic support rod 202 retracts, the bearing roller 203 can be lifted off the ground, and the working state of using the V-shaped inclined leg members 201 to support the ground can be switched.

[0073] An enlarged steel backing plate 204 is provided at the bottom end of the V-shaped inclined leg members 201, which can increase the support area and has better stability and safety.

[0074] The arc-shaped support beam 3 is the main stress-bearing structure for bearing the initial support stress. It is arranged in three sections, including an arch-shaped steel beam 301. Side arc-shaped steel beams 302 are symmetrically provided at both ends of the arch-shaped steel beam 301. Lap joints 3011 are provided at the bottom surfaces of both ends of the arch-shaped steel beam 301, and matching lap grooves 3021 are provided at the upper ends of the side arc-shaped steel beams. The three arc-shaped steel beams are lapped through the groove shape in the extended support state, so that an arc-shaped stress-bearing structure that supports each other is formed between the three arc-shaped steel beams, and the support strength is better. And a telescopic support foot 303 is provided at the bottom end of the side arc-shaped steel beam 302. The telescopic support foot 303 can be telescoped by a hydraulic / electric jack or an internal hydraulic cylinder. In the retracted and mobile state, the telescopic support foot 303 retracts and is lifted off the ground, which is more convenient for movement. In the extended support state, the telescopic support foot 303 touches the ground, effectively increasing the support strength.

[0075] The bottom end of the telescopic support foot 303 is set as an enlarged support foot 3031, which can increase the support area and has better stability and safety.

[0076] In addition, wear-resistant buffer gaskets 12 are provided at the lap joints 3011 of the arch-shaped steel beam and the lap grooves 3021 of the side arc-shaped steel beam, so that it has a certain buffer deformation ability and a longer service life.

[0077] A method based on the above combined arch protection trolley includes the following steps:

[0078] S1. During the normal construction stage of the tunnel, multiple arch protection unit bodies can be connected into a whole through the telescopic longitudinal connecting member 5 to form a combined arch protection trolley, which is arranged and reserved at the tail of the upper or middle bench 13 in the tunnel.

[0079] S2. When cracks, deformations, settlements, convergences, etc. occur in the initial support, the deformation range of the initial support is determined by measurement means, and the initial support deformation is judged to determine whether the initial support is slightly cracked or intruded.

[0080] S3. Mobilize part or all of the combined arch support trolley to quickly move to the initial support deformation section according to the deformation range, and switch to the expanded support form to carry out support reinforcement for the deformation section;

[0081] S4. If it is mild cracking deformation, carry out radial grouting reinforcement operation on the deformed section;

[0082] S4'. If it is intrusion deformation, adopt the construction plan of replacing the arch section by section until all the intruded initial support is demolished and rebuilt, and complete the radial grouting reinforcement construction for all sections.

[0083] Specifically see Figures 13 - 14 ,

[0084] In step S1, during the normal construction stage of the tunnel,

[0085] S1.1. The multi-section arch support units can be connected into a whole through the telescopic longitudinal connecting member 5 to form a combined arch support trolley;

[0086] S1.2. Arrange the combined arch support trolley at the tail of the upper or middle bench 13 in the tunnel and in the retracted moving form. Specifically, the arch-shaped steel beam 301 and the side arc-shaped steel beams 302 on both sides are in the retracted state, the telescopic support rods 202 of the traveling mechanism extend, so that the bearing rollers 203 touch the ground, and at the same time, the telescopic support feet 303 at the bottom of the side arc-shaped steel beam retract to be in a suspended state;

[0087] S1.3. Arrange the tunnel escape pipe 14 at the side position of the combined arch support trolley;

[0088] During the normal construction stage of the tunnel, the combined arch support trolley has no direct contact with the initial support and has no impact on the stress of the initial support, but it can be used as a countermeasure to prevent the sudden settlement and instability of the initial support caused by the excavation of the lower bench;

[0089] Construction vehicles and construction personnel can pass through the lower passage of the arched workbench;

[0090] When the tunnel advances forward, the combined arch support trolley moves forward driven by the bearing rollers 203.

[0091] In step S2, when the initial support shows cracking deformation, settlement deformation, convergence deformation, etc.,

[0092] Specifically see Figure 15 , drive the combined arch support trolley to the initial support deformation section through the bearing rollers 203, and adjust the longitudinal distance between the multi-section arch support units through the telescopic longitudinal connecting member 5 in combination with the actual situation of the initial support, and then switch the combined arch support trolley to the expanded support form,

[0093] Specifically, it includes the following expansion steps:

[0094] Retract the telescopic support rod 202 of the traveling mechanism so that the bearing roller 203 is disengaged from the ground, and expand the contact of the steel backing plate 204 with the ground;

[0095] Simultaneously extend the first telescopic mechanism 401 to drive the arched curved steel beam 301 to expand outward and abut against the primary support;

[0096] Simultaneously extend the second telescopic mechanism 402, and then drive the side curved steel beam 302 to expand, overlap with the arched curved steel beam 301, and abut against the primary support;

[0097] Extend the telescopic support feet 303 at the bottom of the side curved steel beam 302 to expand the contact of the support feet 3031 with the ground, and make the steel ring beam composed of the arched curved steel beam 301 and the two side curved steel beams 302 in a tightly stressed state;

[0098] In step s3, the force on the primary support is monitored by the monitoring and measuring equipment 7 provided on the arched support beam 3 of the arch protection unit body. Specifically, it includes detecting the deformation pressure of the primary support through the earth pressure cell 701 provided on the top of the arched support beam 3, and detecting the stress of the arched support beam 3 through the steel bar stress gauge 702 provided on the inner side of the arched support beam 3; Through monitoring and observation, combined with the detection values of the earth pressure cell 701 and the steel bar stress gauge 702, the force condition of the primary support is judged, providing a basis for determining the subsequent specific support parameters.

[0099] Specifically, see Figure 16 ,

[0100] In step s4, if it is a minor cracking deformation, there is no need to replace the arch. Specifically, the following operations are as follows:

[0101] S4.1. According to the actual situation, mobilize some or all of the combined arch protection trolleys to quickly move to the deformation section of the primary support and switch to the extended support form to ensure safety during construction. At this time, there is no need to suspend the construction of the heading face personnel;

[0102] S4.2. The construction vehicles and construction personnel are in place. The construction personnel can simultaneously carry out radial grouting reinforcement operations on the deformation section of the primary support on the arched working platforms 1 of multiple arch protection unit bodies. After the grouting is completed and the grout has solidified, withdraw the combined arch protection trolley to the tail of the upper or middle bench 13 and wait for the next call.

[0103] Specifically, see Figures 17 - 21 ,

[0104] In step s4', if it is an intrusion deformation, it is necessary to replace the arch. Specifically, the following operations are as follows:

[0105] S4.1’, immediately evacuate the workers at the heading face and suspend the tunneling construction at the heading face;

[0106] S4.2’, according to the actual situation, mobilize part or all of the combined arch support trolley to quickly move to the initial support deformation section and switch to the expanded support form to prevent the possible instability failure of the initial support;

[0107] S4.3’, the construction vehicles and construction personnel are in place. The construction personnel use the first arch support unit body to install the inclined grouting small ducts 15 from behind the undeformed I-beam to the section where the initial support intrudes into the secondary lining limit, and grout the surrounding rock for reinforcement;

[0108] S4.4’, after the construction of step S4.3’ is completed, the first arch support unit body switches to the retracted moving form, detaches from the subsequent arch support unit bodies, and drives back to the tail of the upper or middle bench 13. Then the construction vehicles and construction personnel are in place at the second arch support unit body;

[0109] S4.5’, the construction personnel demolish and reconstruct the initial support that intrudes into the secondary lining limit under the protection of the arch support trolley and the first cycle of inclined grouting pipes. Then, the radial grouting small ducts 16 are installed to conduct secondary grouting reinforcement for the arch replacement section to ensure the subsequent structural reliability of the initial support in this section;

[0110] S4.6’, install the second cycle of inclined grouting small ducts 15 from behind the replaced I-beam to the section where the arch has not been replaced, and grout the surrounding rock for reinforcement;

[0111] S4.7’, repeat steps S4.3’ to S4.6’, organize the deployment and construction of the combined arch support trolley, construction vehicles and construction personnel in an orderly manner. The idle arch support unit bodies drive back to the tail of the upper or middle bench 13 and are connected as a whole, waiting for the next call;

[0112] S4.8’, use the above-mentioned method of replacing the arch by each section to construct until all the initial support that intrudes into the limit is completely demolished and reconstructed, and complete the radial grouting reinforcement construction for all sections.

[0113] Considering that all the sections where the initial support intrudes into the limit have been replaced, no inclined grouting small ducts 15 will be installed in this section during the subsequent construction.

[0114] The construction vehicles transport the waste residues generated during the arch replacement process out of the tunnel, restore the traffic in the tunnel, and then resume the tunneling construction at the heading face.

[0115] As mentioned above, it is only a preferred embodiment of the present invention, and there is no restriction on the present invention in any form of confidentiality. Any simple modification, equivalent change and modification made to the above embodiments based on the technical content of the present invention and without departing from the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A combined arch support trolley for initial support and reinforcement of tunnels, characterized in that: It is composed of multiple sections of movable arch protection unit bodies spliced together; the arch protection unit body includes an arched workbench (1), a traveling mechanism (2) is arranged at the bottom of the arched workbench (1), and multiple arc-shaped support beams (3) that are lapped together to form an arched structure are arranged on one side of the top. Each arc-shaped support beam (3) is connected to the arched workbench (1) through a telescopic mechanism (4); The arc-shaped support beam (3) is arranged in three sections, including an arch arc-shaped steel beam (301), side arc-shaped steel beams (302) are symmetrically arranged at both ends of the arch arc-shaped steel beam (301). Lapping sections (3011) are arranged at the bottom surfaces of both ends of the arch arc-shaped steel beam (301), and lapping grooves (3021) matching thereto are arranged at the upper ends of the side arc-shaped steel beams (302). The three arc-shaped steel beams are lapped through the grooves in the extended support state, so that a structure of supporting each other is formed between the three arc-shaped steel beams; and telescopic support feet (303) are arranged at the bottom ends of the side arc-shaped steel beams (302); Wear-resistant buffer gaskets (12) are arranged at the lapping sections (3011) of the arch arc-shaped steel beam and the lapping grooves (3021) of the side arc-shaped steel beam, so that it has a certain buffer deformation ability; The arched workbench (1) includes a platform frame (101) arranged in multiple layers of steps. A support frame (102) arranged in an arched structure is arranged on one side of the platform frame (101), and mounting seats (103) for fixing the telescopic mechanism (4) are arranged on the support frame (102); Columns (104) are arranged at the bottoms of the platform frame (101) and the support frame (102), and the traveling mechanism (2) is arranged at the bottom ends of the columns (104); The traveling mechanism (2) includes a V-shaped inclined leg member (201) at the bottom of the column (104), and an enlarged steel backing plate (204) is arranged at the bottom end of the V-shaped inclined leg member (201); And a telescopic support rod (202) and a bearing roller (203) connected thereto are arranged in the middle of the V-shaped inclined leg member (201); The platform frame (101) and the support frame (102) are of a detachable connection structure.

2. The combined arch support trolley for initial support and reinforcement of tunnels according to claim 1, characterized in that: Adjacent arch protection unit bodies are detachably connected through a telescopic longitudinal connection member (5).

3. The combined arch support trolley for initial support reinforcement of tunnels according to claim 2, wherein: Monitoring and measuring equipment (7) is also arranged on the arc-shaped support beam (3) of the arch protection unit body. The monitoring and measuring equipment (7) includes an earth pressure cell (701) arranged at the top of the arc-shaped support beam (3), and a reinforcing bar stress gauge (702) arranged on the inner side of the arc-shaped support beam (3).

4. A method for initial support and reinforcement of tunnels, characterized in that, It is realized by using the combined arch protection trolley described in claim 1, and includes the following steps: S1. During the normal construction stage of the tunnel, multiple sections of arch protection unit bodies can be connected into a whole through the telescopic longitudinal connection member (5) to form a combined arch protection trolley, which is arranged and reserved at the tail of the upper or middle bench (13) in the tunnel; S2. When initial support cracking deformation, settlement deformation, convergence deformation and other situations occur, the deformation range of the initial support is determined by measuring means, and the initial support deformation is judged to determine whether the initial support is mild cracking deformation or intrusion deformation; s3. Mobilize some or all of the combined arch support trolleys to quickly move to the initial support deformation section according to the deformation range, switch to the extended support form, and carry out support reinforcement for the deformation section; s4. If it is judged as mild cracking deformation, carry out radial grouting reinforcement operation on the deformed section; s4'. If it is judged as intrusion deformation, construct according to the plan of replacing the arch piece by piece until all the intruded initial supports are completely demolished and rebuilt, and complete the radial grouting reinforcement construction for all sections; In step s4', if it is judged as intrusion deformation, perform the following operations: s4.1'. Immediately let the workers at the heading face evacuate and suspend the heading face tunneling construction; s4.2'. Mobilize some or all of the combined arch support trolleys to quickly move to the initial support deformation section according to the actual situation and switch to the extended support form to prevent possible instability failure of the initial support; s4.3'. The construction vehicles and construction personnel are in place. The construction personnel use the first arch support unit body to construct inclined grouting small pipes (15) from behind the undeformed I-beam to the initial support intrusion section, and grout and reinforce the surrounding rock; s4.4'. After the construction in step s4.3' is completed, the first arch support unit body switches to the retracted moving form, detaches from the subsequent arch support unit bodies, and drives back to the tail of the upper or middle bench (13). Then the construction vehicles and construction personnel are in place at the second arch support unit body; s4.5'. The construction personnel demolish and rebuild the initial support that intrudes into the secondary lining limit under the protection of the arch support trolley and the first cycle of inclined grouting pipes. Then, construct radial grouting small pipes (16) to perform secondary grouting reinforcement on the arch replacement section to ensure the subsequent structural reliability of the initial support in this section; s4.6'. Construct the second cycle of inclined grouting small pipes (15) from behind the replaced I-beam to the section where the arch has not been replaced, and grout and reinforce the surrounding rock; s4.7'. Repeat steps s4.3' to s4.6', organize the deployment and construction of the combined arch support trolleys, construction vehicles and construction personnel in an orderly manner. The idle arch support unit bodies drive back to the tail of the upper or middle bench (13) and are connected as a whole, waiting for the next call; s4.8'. Construct according to the plan of replacing the arch piece by piece until all the intruded initial supports are completely demolished and rebuilt, and complete the radial grouting reinforcement construction for all sections.

5. The method for initial support reinforcement of a tunnel according to claim 4, characterized in that: In step s3, the stress of the initial support is monitored through the monitoring and measuring equipment (7) provided on the arc support beam (3) of the arch support unit body. The deformation pressure of the initial support is detected by the earth pressure cell (701), and the stress of the arc support beam (3) is detected by the steel bar stress gauge (702); Through monitoring and measuring observation, combined with the detection values of the earth pressure cell (701) and the steel bar stress gauge (702), judge the deformation condition of the initial support.

6. The method for initial support reinforcement of a tunnel according to claim 4, characterized in that: In step s4, if it is judged as mild cracking deformation, perform the following operations: s4.

1. Mobilize some or all of the combined arch support trolleys to quickly move to the initial support deformation section according to the actual situation and switch to the extended support form to ensure safety during construction. At this time, there is no need to suspend the construction of the heading face personnel; S4.

2. The construction vehicles and construction personnel are in place. The construction personnel can simultaneously carry out radial grouting reinforcement operations on the initial support deformation section on the arched workbench (1) of multiple sections of the arch protection unit. After the grouting is completed and the grout solidifies, the combined arch protection trolley is withdrawn to the tail of the upper or middle bench (13) and waits for the next call.

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