A temporary tunnel support structure and its usage method

Abstract

The present invention is a temporary support structure for a tunnel and a method for using the same, wherein the temporary support structure for a tunnel comprises a plurality of groups of support units arranged closely along the extension direction of the tunnel, each group of support units comprising a splicing fixed plate assembly, an upper concrete pad abutting against the top of the splicing fixed plate assembly, and a lower concrete pad abutting against the bottom of the splicing fixed plate assembly. A plurality of upper adjustment rods that can extend upward and abut against the upper concrete pad are provided in the top of the splicing fixed plate assembly, and a plurality of lower adjustment rods that can extend downward and abut against the lower concrete pad are provided in the bottom of the splicing fixed plate assembly. A plurality of upper steel bars extending upward are provided on the top surface of the upper concrete pad, and a plurality of lower steel bars extending downward are provided on the bottom surface of the lower concrete pad. The present invention can temporarily support the excavated part of the tunnel in a relatively short time and is easy to dismantle, and can effectively solve the problems of long construction period of traditional temporary support, huge consumption of building materials and difficulty in recycling.

Description

Technical Field

[0001] The present invention relates to the technical field of building structures, and particularly to a temporary support structure for a tunnel and a using method thereof. Background Art

[0002] With the gradual improvement of the national transportation network, tunnel construction has been more and more widely applied. During the tunnel construction process, large cross-sections have gradually become a trend in the development of tunnel engineering. When excavating a large cross-section tunnel, due to the too large cross-section of the tunnel, it is often very difficult to form it in one go. Considering the instability of the surrounding rock properties, it is necessary to adopt the method of sectional excavation for operation. However, whether it is the single-side drift method, the double-side drift method, or the CD method (center diaphragm method), the CRD method (cross center diaphragm method), etc., certain reinforcement measures need to be taken for the soil body to be excavated within the face to prevent local collapse during tunnel excavation. Therefore, when excavating the tunnel face sectionally, a temporary support structure is often required to be set on the side wall of the soil body to be excavated in the drift.

[0003] The traditional temporary support structure for a tunnel is supported by the method of shotcrete with steel mesh, and it is removed after the lining and the surrounding rock tend to be stable. This construction method, although relatively simple, consumes a large amount of materials and is not recyclable. As the tunnel construction progresses, it is very easy to develop into a large amount of construction waste. In addition, this kind of temporary support structure needs to fully react inside the concrete and can only play its normal role after the cement solidifies, which also has a certain impact on the construction efficiency. Considering the later soil excavation, this kind of temporary support structure often has small anchor rods remaining in the soil body to be excavated, which will also cause certain interference to the later soil excavation.

[0004] Currently, our country pays increasing attention to environmental protection and green development. In tunnel engineering, it is particularly necessary to pay attention to improving various technologies for tunnel construction and reducing the generation of construction waste. At present, although there are also some detachable temporary support structures for tunnels, they generally have the following disadvantages: (1) The existing technologies only consider the temporary support system under the condition of full-section excavation of the tunnel, and are not very applicable to sectional excavation; (2) The existing technologies occupy too high a proportion of the tunnel construction surface and cannot achieve immediate reinforcement during tunnel construction; (3) The service objects of the existing technologies are relatively small, and the adaptability to the construction process of super-large cross-section tunnels is poor, and they cannot well assist the sectional excavation process of super-large cross-section tunnels.

[0005] Therefore, based on the experience and practice of being engaged in the relevant industry for many years, the inventor of the present invention proposes a temporary support structure for a tunnel and a using method thereof to overcome the defects of the existing technologies. Summary of the Invention

[0006] The object of the present invention is to provide a temporary support structure for a tunnel and its usage method, which can carry out temporary support for the excavated part of the tunnel in a relatively short time, is easy to demolish, and can effectively solve the problems of long construction period, huge consumption of building materials and difficulty in recycling of traditional temporary supports.

[0007] The object of the present invention can be achieved by the following technical solutions:

[0008] The present invention provides a temporary support structure for a tunnel, which includes multiple groups of support units arranged adjacent to each other along the extension direction of the tunnel; each group of support units includes a splicing fixed plate assembly, an upper concrete cushion plate abutted above the splicing fixed plate assembly, and a lower concrete cushion plate abutted below the splicing fixed plate assembly. A plurality of upper adjusting rods capable of extending upward and abutting against the upper concrete cushion plate are arranged inside the top of the splicing fixed plate assembly, and a plurality of lower adjusting rods capable of extending downward and abutting against the lower concrete cushion plate are arranged inside the bottom of the splicing fixed plate assembly; a plurality of upper steel bars extending upward are arranged on the top surface of the upper concrete cushion plate, and a plurality of lower steel bars extending downward are arranged on the bottom surface of the lower concrete cushion plate.

[0009] In a preferred embodiment of the present invention, the splicing fixed plate assembly in each group of support units includes a plurality of outer connecting plates arranged adjacent to each other from top to bottom, a plurality of inner connecting plates arranged adjacent to each other from top to bottom and aligned with the plate surfaces of the respective outer connecting plates, a plurality of middle support plates arranged adjacent to each other from top to bottom and clamped between the respective outer connecting plates and inner connecting plates, an upper pressing plate clamped between the top outer connecting plate and inner connecting plate and abutted above the top middle support plate, and a lower pressing plate clamped between the bottom outer connecting plate and inner connecting plate and abutted below the bottom middle support plate; between each outer connecting plate and the corresponding middle support plate and the corresponding inner connecting plate, between the upper pressing plate and the top outer connecting plate and inner connecting plate, and between the lower pressing plate and the bottom outer connecting plate and inner connecting plate, they are detachably fixedly connected through a plurality of fixing members; the outer sides of each outer connecting plate are used for abutting against the inner wall of the pilot tunnel of the tunnel, and the plate surfaces of each middle support plate and each outer connecting plate are staggered from top to bottom; each upper adjusting rod is arranged in the upper pressing plate, and each lower adjusting rod is arranged in the lower pressing plate; the upper concrete cushion plate abuts above the upper pressing plate, the top outer connecting plate and the top inner connecting plate, and the lower concrete cushion plate abuts below the lower pressing plate, the bottom outer connecting plate and the bottom inner connecting plate.

[0010] In a preferred embodiment of the present invention, a plurality of upper through holes are opened at positions corresponding to the respective upper adjusting rods on the upper concrete cushion plate, and each upper adjusting rod can extend into the corresponding upper through hole; a plurality of lower through holes are opened at positions corresponding to the respective lower adjusting rods on the lower concrete cushion plate, and each lower adjusting rod can extend into the corresponding lower through hole.

[0011] In a preferred embodiment of the present invention, upper concrete columns are slidably inserted into each of the upper through holes, and lower concrete columns are slidably inserted into each of the lower through holes.

[0012] In a preferred embodiment of the present invention, an upper rubber gasket is clamped between the upper concrete pad and the upper pressing plate, and a plurality of upper through holes are formed in the upper rubber gasket corresponding to the positions of the respective upper adjusting rods; a lower rubber gasket is clamped between the lower concrete pad and the lower pressing plate, and a plurality of lower through holes are formed in the lower rubber gasket corresponding to the positions of the respective lower adjusting rods.

[0013] In a preferred embodiment of the present invention, an upper cast-in-place concrete layer is provided on the top surface of the upper concrete pad corresponding to the positions of the respective upper steel bars, and a lower cast-in-place concrete layer is provided on the bottom surface of the lower concrete pad corresponding to the positions of the respective lower steel bars.

[0014] In a preferred embodiment of the present invention, the outer connecting plate, the inner connecting plate, the middle supporting plate, the upper pressing plate, the lower pressing plate, the upper concrete pad and the lower concrete pad are all arc-shaped plates.

[0015] In a preferred embodiment of the present invention, a plurality of upper threaded holes penetrating through the top and bottom surfaces thereof are provided in the upper pressing plate, each upper adjusting rod is an upper rotating screw rod and is respectively inserted into the corresponding upper threaded hole, and a plurality of upper operation windows respectively communicating with the respective upper threaded holes are formed on the side surface of the upper pressing plate facing away from the outer connecting plate; a plurality of lower threaded holes penetrating through the top and bottom surfaces thereof are provided in the lower pressing plate, each lower adjusting rod is a lower rotating screw rod and is respectively inserted into the corresponding lower threaded hole, and a plurality of lower operation windows respectively communicating with the respective lower threaded holes are formed on the side surface of the lower pressing plate facing away from the outer connecting plate; a hollow hole is formed in each inner connecting plate, and the hollow hole in the top inner connecting plate can communicate with all the upper operation windows, and the hollow hole in the bottom inner connecting plate can communicate with all the lower operation windows.

[0016] In a preferred embodiment of the present invention, the fixing member is a reverse screw rod fixed on the outer connecting plate and having a rod body facing away from the inner connecting plate, and the reverse screw rod sequentially passes through the upper pressing plate and the top inner connecting plate, sequentially passes through each middle supporting plate and the corresponding inner connecting plate or sequentially passes through the lower pressing plate and the bottom inner connecting plate and is connected by a nut.

[0017] In a preferred embodiment of the present invention, a plurality of connecting members are detachably fixed on the splicing fixing plate assembly, and the outer ends of each connecting member all extend out of the outer side of the splicing fixing plate assembly and are detachably and fixedly connected with an anchor member, a sealing member or a horizontal support pipe.

[0018] In a preferred embodiment of the present invention, the connecting member is a sleeve structure, and a convex ring protrudes outwards from the inner side end of the sleeve structure, and the convex ring is connected with the splicing fixing plate assembly through a plurality of bolts.

[0019] In a preferred embodiment of the present invention, the outer side end of the sleeve structure is threadedly connected with the end of the anchor member, and each anchor member is used for being inserted into a corresponding slot hole formed in the soil to be excavated.

[0020] In a preferred embodiment of the present invention, the closure member is a cylindrical structure with one end open, and the open end of the cylindrical structure is threadedly connected to the outer end of the sleeve structure.

[0021] In a preferred embodiment of the present invention, a transition elbow is threadedly connected to the outer end of the sleeve structure, and the transition elbow is threadedly connected to the end of the horizontal support pipe.

[0022] In a preferred embodiment of the present invention, the plate surface of the middle support plate is aligned with the plate surface of the corresponding external connection plate along the extension direction of the tunnel; or

[0023] The plate surface of the middle support plate is arranged offset from the plate surface of the corresponding external connection plate along the extension direction of the tunnel, and in multiple groups of support units, a part of the middle support plate in each group of support units is clamped between the external connection plate and the internal connection plate of the adjacent support unit.

[0024] The present invention also provides a method for using the above-mentioned temporary tunnel support structure, including the following steps:

[0025] S1. According to the cross-sectional shape of the tunnel and the excavation method of the pilot drift method, manufacture the upper concrete cushion plate and upper steel bars, as well as the lower concrete cushion plate and lower steel bars with corresponding dimensions;

[0026] S2. Insert each of the lower steel bars at the bottom of the lower concrete cushion plate into the bottom wall of the excavated soil body at the corner of the pilot drift, and then assemble and fix them from bottom to top to form an assembled fixed plate assembly;

[0027] S3. Place the upper concrete cushion plate on top of the assembled fixed plate assembly, and insert each of the upper steel bars into the top wall of the excavated soil body at the corner of the pilot drift;

[0028] S4. Adjust each of the upper adjusting rods to extend upward and press the upper concrete cushion plate; adjust each of the lower adjusting rods to extend downward and press the lower concrete cushion plate;

[0029] S5. After the primary lining of the tunnel is stable, adjust each of the upper adjusting rods and each of the lower adjusting rods to retract into the assembled fixed plate assembly, and then disassemble the assembled fixed plate assembly from top to bottom to complete the removal of the temporary tunnel support structure.

[0030] In a preferred embodiment of the present invention, a plurality of upper concrete columns are slidably inserted into a plurality of upper through holes formed in the upper concrete cushion plate, and a plurality of lower concrete columns are slidably inserted into a plurality of lower through holes formed in the lower concrete cushion plate; in step S4, after each of the upper adjusting rods extends upward, it is inserted into the corresponding upper through hole, and pushes the corresponding upper concrete column to extend upward and insert into the top wall of the excavated soil body; after each of the lower adjusting rods extends downward, it is inserted into the corresponding lower through hole, and pushes the corresponding lower concrete column to extend downward and insert into the bottom wall of the excavated soil body.

[0031] In a preferred embodiment of the present invention, in step S2, a part of each lower steel bar is inserted into the bottom wall of the excavated soil mass, and concrete is cast-in-place between the lower concrete cushion plate and the part of the lower steel bar on the bottom wall of the excavated soil mass to form a lower cast-in-place concrete layer; in step S3, a part of each upper steel bar is inserted into the top wall of the excavated soil mass, and concrete is cast-in-place between the upper concrete cushion plate and the part of the upper steel bar on the top wall of the excavated soil mass to form an upper cast-in-place concrete layer.

[0032] In a preferred embodiment of the present invention, the following steps are further included between step S1 and step S2:

[0033] S15. Determine the arrangement of a plurality of anchor rod members, and perform grooving treatment on the soil mass to be excavated to form a plurality of groove holes;

[0034] The following steps are further included between step S2 and step S3:

[0035] S25. Connect the ends of the plurality of anchor rod members to the outer ends of the corresponding connecting members, insert and fix each connecting member in the assembled fixing plate assembly, and make the outer ends of each connecting member extend out of the outside of the assembled fixing plate assembly, and each anchor rod member is inserted into the corresponding groove hole;

[0036] The following steps are further included between step S4 and step S5:

[0037] S45. When excavating the soil mass in the anchorage area of each anchor rod member, disconnect the corresponding anchor rod member from the corresponding connecting member, and then connect the outer ends of some connecting members to a sealing member, and connect the outer ends of the other part of the connecting members to a horizontal support pipe;

[0038] In step S5, when disassembling the assembled fixing plate assembly, disassemble each connecting member, each sealing member and each horizontal support pipe.

[0039] As described above, through the assembly of the splicing fixing plate assembly, the present invention can realize the rapid assembly of the entire support structure. Through the cooperation of the upper concrete cushion plate and the lower concrete cushion plate with each steel bar, for different tunnel excavation sizes, it can ensure the stable contact between the entire support structure and the top wall and bottom wall of the excavated soil mass in the pilot tunnel, and quickly play a role in reliable force transmission. At the same time, through the setting of each adjusting rod, prestress can be applied to the entire support structure, realizing the firm extrusion between the support structure and the surrounding rock, increasing the effect of the support structure to resist the lateral earth pressure of the soil mass to be excavated, and improving the safety and stability of the entire support structure. In addition, when demolishing the support structure, not only the demolition efficiency is high, but also each component of the splicing fixing plate assembly can be reused, saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The following drawings are only intended to illustrate and explain the present invention schematically and do not limit the scope of the present invention. Among them:

[0041] Figure 1 : Schematic diagram of the structure of the temporary tunnel support structure provided by the present invention when the middle support plate adopts the first splicing method.

[0042] Figure 2 : Three-dimensional view of the assembly between the lower concrete pad, the external connecting plate at the bottom, the internal connecting plate at the bottom, the middle support plate at the bottom and the lower pressing plate when the middle support plate adopts the first splicing method provided by the present invention.

[0043] Figure 3 : Schematic diagram of the structure of the external connecting plate provided by the present invention.

[0044] Figure 4 : Side view of the external connecting plate provided by the present invention.

[0045] Figure 5 : Schematic diagram of the structure of the middle support plate provided by the present invention.

[0046] Figure 6 : Side view of the middle support plate provided by the present invention.

[0047] Figure 7 : Schematic diagram of the structure of the internal connecting plate provided by the present invention.

[0048] Figure 8 : Side view of the internal connecting plate provided by the present invention.

[0049] Figure 9 : Schematic diagram of the matching structure when the external connecting plate and the middle support plate of the invention adopt the first splicing method.

[0050] Figure 10 : Schematic diagram of the structure of the upper pressing plate provided by the present invention.

[0051] Figure 11 : Schematic diagram of the structure of the lower pressing plate provided by the present invention.

[0052] Figure 12 : Three-dimensional sectional view of the lower pressing plate provided by the present invention.

[0053] Figure 13 : Schematic diagram of the structure of the lower concrete pad provided by the present invention.

[0054] Figure 14 : Three-dimensional view of the lower concrete pad provided by the present invention.

[0055] Figure 15 : Schematic diagram of the matching structure between the connecting piece and the bolt piece provided by the present invention.

[0056] Figure 16 : Schematic diagram of the structure of the sealing piece provided by the present invention.

[0057] Figure 17 : Schematic structural diagram of the adapter elbow provided by the present invention.

[0058] Figure 18 : Schematic structural diagram of the horizontal support pipe provided by the present invention.

[0059] Figure 19 : Schematic structural diagram of the two tunnel temporary support structures during construction using the double-sided pilot drift method after removing the anchor rod members and connecting the closure member and the horizontal support pipe.

[0060] Figure 20 : Schematic structural diagram of the tunnel temporary support structure when the middle support plate adopts the second splicing method.

[0061] Figure 21 : Another schematic structural diagram of the external connection plate provided by the present invention.

[0062] Figure 22 : Another schematic structural diagram of the middle support plate provided by the present invention.

[0063] Figure 23 : Another schematic structural diagram of the internal connection plate provided by the present invention.

[0064] Figure 24 : Schematic structural diagram of the cooperation between the external connection plate and the middle support plate when they adopt the second splicing method.

[0065] Figure 25 : Another schematic structural diagram of the upper pressing plate provided by the present invention.

[0066] Figure 26 : Another schematic structural diagram of the lower pressing plate provided by the present invention.

[0067] Explanation of the reference numerals in the drawings:

[0068] 100, Tunnel temporary support structure;

[0069] 1, External connection plate;

[0070] 2, Internal connection plate; 21, Hollow hole;

[0071] 3, Middle support plate;

[0072] 4, Upper pressing plate; 41, Upper adjusting rod; 42, Upper threaded hole; 43, Upper operation window;

[0073] 5, Lower pressing plate; 51, Lower adjusting rod; 52, Lower threaded hole; 53, Lower operation window;

[0074] 6, Upper concrete cushion plate; 61, Upper concrete column; 62, Upper cast-in-place concrete layer;

[0075] 7. Lower concrete cushion plate; 71. Lower reinforcing bar; 72. Lower through hole; 73. Lower concrete column; 74. Lower cast-in-place concrete

[0076] layer; 75. Lower rubber gasket

[0077] 8. Fixing member; 81. Installation hole

[0078] 9. Connecting member; 901. Convex ring; 902. Perforation; 903. Bolt hole

[0079] 91. Anchor rod member; 92. Sealing member; 93. Adapter elbow; 94. Horizontal support pipe Specific implementation manner

[0080] For a clearer understanding of the technical features, objectives, and effects of the present invention, the specific implementation manner of the present invention will now be described with reference to the accompanying drawings.

[0081] As Figures 1 to 26 shown, this embodiment provides a tunnel temporary support structure, which includes multiple groups of support units arranged adjacent to each other along the extension direction of the tunnel. Each group of support units includes a spliced fixed plate assembly, an upper concrete cushion plate 6 abutted above the spliced fixed plate assembly, and a lower concrete cushion plate 7 abutted below the spliced fixed plate assembly. Inside the top of the spliced fixed plate assembly, there are multiple upper adjusting rods 41 that can extend upward and abut against the upper concrete cushion plate 6, and inside the bottom of the spliced fixed plate assembly, there are multiple lower adjusting rods 51 that can extend downward and abut against the lower concrete cushion plate 7. On the top surface of the upper concrete cushion plate 6, there are multiple upper reinforcing bars extending upward, and on the bottom surface of the lower concrete cushion plate 7, there are multiple lower reinforcing bars 71 extending downward.

[0082] Among them, the entire tunnel temporary support structure 100 is mainly used for drift method construction. The top surface, bottom surface, and one side surface of the entire drift are all excavated soil, and the other side surface is soil to be excavated. The tunnel temporary support structure 100 is arranged on the side wall of the soil to be excavated in the drift to replace the support method of shotcrete with wire mesh in the prior art.

[0083] During actual construction, since the corners of the pilot pit are basically uneven, and each splicing plate in the splicing fixing plate assembly is generally made according to standard size, and the number of splicing plates is selected according to different tunnel sizes; when applied to tunnel excavation surfaces of different sizes, after the splicing fixing plate assembly is completed, there is basically a gap between the top and bottom of the entire splicing fixing plate assembly and the surrounding rock, and stable force transmission cannot be formed. In this embodiment, by setting the upper concrete pad 6 and the lower concrete pad 7, the size of the upper concrete pad 6 and the lower concrete pad 7 can be designed according to different tunnel sizes. During installation, the multiple lower steel bars 71 of the lower concrete pad 7 are inserted into the bottom wall of the excavated soil body of the pilot pit, and the multiple upper steel bars on the upper concrete pad 6 are inserted into the top wall of the excavated soil body of the pilot pit, which can effectively ensure the stable contact and fixation of the entire support structure with the top and bottom surrounding rocks, effectively transmit the axial soil pressure from top to bottom, and use each steel bar to quickly achieve the role of stable contact and force transmission. The multiple upper steel bars above each upper concrete pad 6 and the multiple lower steel bars 71 below each lower concrete pad 7 are preferably arranged densely to form a steel bar group to ensure structural stability; the length of the steel bars and the placement angle during installation are also flexibly adjusted according to the pilot pit excavation form and specific construction conditions.

[0084] In addition, after the splicing fixing plate assembly and the upper concrete pad 6 and the lower concrete pad 7 are installed, adjusting each lower adjusting rod 51 to extend downward can produce a squeezing effect on the splicing fixing plate assembly and the lower concrete pad 7 respectively, and increase the friction between the bottom surface of the splicing fixing plate assembly and the lower concrete pad 7; adjusting each upper adjusting rod 41 to extend upward can produce a squeezing effect on the splicing fixing plate assembly and the upper concrete pad 6 respectively, and increase the friction between the top of the splicing fixing plate assembly and the upper concrete pad 6, thereby increasing the effect of the support structure in resisting the lateral earth pressure of the soil to be excavated, and improving the structural stability.

[0085] Therefore, the temporary tunnel support structure 100 in this embodiment can realize the rapid assembly of the entire support structure by assembling the splicing fixed plate assembly. Through the cooperation of the upper concrete pad 6 and the lower concrete pad 7 with each steel bar, the stable contact between the entire support structure and the top wall and bottom wall of the excavated soil of the pilot pit can be guaranteed for different tunnel excavation sizes, and the reliable force transmission can be quickly played. At the same time, through the setting of each adjustment rod, prestress can be applied to the entire support structure, the support structure and the surrounding rock are firmly squeezed, the effect of the support structure to resist the lateral earth pressure of the soil to be excavated is increased, and the safety and stability of the entire support structure are improved. In addition, when dismantling the support structure, not only is the dismantling efficiency high, but also the various components of the splicing fixed plate assembly can be reused, saving costs.

[0086] In a specific implementation manner, in order to more conveniently assemble and fix the splicing fixing plate assembly, the splicing fixing plate assembly in each group of support units includes a plurality of external connection plates 1 arranged adjacent to each other from top to bottom, a plurality of internal connection plates 2 arranged adjacent to each other from top to bottom and aligned with the plate surfaces of the respective external connection plates 1, a plurality of middle support plates 3 arranged adjacent to each other from top to bottom and clamped between the respective external connection plates 1 and internal connection plates 2, an upper pressing plate 4 clamped between the external connection plate 1 and internal connection plate 2 at the top and abutted above the middle support plate 3 at the top, and a lower pressing plate 5 clamped between the external connection plate 1 and internal connection plate 2 at the bottom and abutted below the middle support plate 3 at the bottom.

[0087] Between each external connection plate 1 and the corresponding middle support plate 3 and the corresponding internal connection plate 2, between the upper pressing plate 4 and the external connection plate 1 and internal connection plate 2 at the top, and between the lower pressing plate 5 and the external connection plate 1 and internal connection plate 2 at the bottom, they are all detachably fixedly connected by a plurality of fixing members 8. The outer side of each external connection plate 1 is used to abut against the inner wall of the pilot tunnel of the tunnel. The plate surfaces of each middle support plate 3 and each external connection plate 1 are staggered from top to bottom. Each upper adjusting rod 41 is arranged in the upper pressing plate 4, and each lower adjusting rod 51 is arranged in the lower pressing plate 5. The upper concrete cushion plate 6 abuts above the upper pressing plate 4, the external connection plate 1 at the top, and the internal connection plate 2 at the top, and the lower concrete cushion plate 7 abuts below the lower pressing plate 5, the external connection plate 1 at the bottom, and the internal connection plate 2 at the bottom.

[0088] Among them, the thickness of each middle support plate 3 is greater than the thickness of the external connection plate 1 and the internal connection plate 2, and it is the main load-bearing component; the lengths and heights of the external connection plate 1 and the internal connection plate 2 are basically the same (here, the length refers to the dimension along the extension direction of the tunnel, and the height refers to the dimension along the height direction of the tunnel), and the thicknesses can be different. For example, in this embodiment, the thickness of the external connection plate 1 is greater than the thickness of the internal connection plate 2. The two are mainly used to splice and fix each middle support plate 3 together. The external connection plates 1 and the middle support plates 3 are arranged in a vertically staggered manner, and the connection is more firm. The number of external connection plates 1 and internal connection plates 2 in each group of support units is the same, and both are one more than the number of middle support plates 3. The thicknesses of the upper pressing plate 4 and the lower pressing plate 5 are the same as the thickness of the middle support plate 3, and their heights are approximately half of the height of the middle support plate 3, so that after splicing, the upper pressing plate 4 and the lower pressing plate 5 respectively abut against the upper concrete cushion plate 6 and the lower concrete cushion plate 7.

[0089] Specifically, the outer side of the external connection plate 1 can be attached to the side wall of the soil body to be excavated in the pilot tunnel. Each external connection plate 1, each internal connection plate 2, each middle support plate 3, the upper pressing plate 4, and the lower pressing plate 5 are all preferably made of steel plates and are all manufactured according to standard sizes. Since the sizes of each plate member can be designed to be smaller, the weights of each plate member are lighter, which is more convenient for on-site splicing operations, and can meet the requirements of different tunnel excavation sizes, and is more convenient for flexible adjustment.

[0090] In order to further improve the stability of the structure, such as Figure 13 and Figure 14As shown, a plurality of upper through holes are formed in the upper concrete cushion plate 6 at positions corresponding to the respective upper adjusting rods 41, and each upper adjusting rod 41 can extend into the corresponding upper through hole. A plurality of lower through holes 72 are formed in the lower concrete cushion plate 7 at positions corresponding to the respective lower adjusting rods 51, and each lower adjusting rod 51 can extend into the corresponding lower through hole 72.

[0091] Among them, each upper through hole penetrates through the top surface and the bottom surface of the upper concrete cushion plate 6, and each lower through hole 72 penetrates through the top surface and the bottom surface of the lower concrete cushion plate 7. When adjusting the upper adjusting rods 41 and the lower adjusting rods 51 after the installation of each plate body, the upper adjusting rods 41 and the lower adjusting rods 51 respectively extend into the corresponding upper through holes and lower through holes 72, which can effectively connect the upper pressure plate 4 and the upper concrete cushion plate 6 and the lower pressure plate 5 and the lower concrete cushion plate 7 into a whole, further increasing the friction force between the upper pressure plate 4 and the upper concrete cushion plate 6 and between the lower pressure plate 5 and the lower concrete cushion plate 7, and effectively improving the effect of the support structure in resisting the lateral earth pressure of the soil to be excavated. At the same time, it can also avoid damage to the concrete cushion plate caused by excessive force when each adjusting rod directly abuts against the corresponding concrete cushion plate.

[0092] More preferably, as Figure 1 and Figure 13 shown, an upper concrete column 61 is slidably inserted into each upper through hole, and a lower concrete column 73 is slidably inserted into each lower through hole 72. The upper concrete column 61 and the lower concrete column 73 are preferably cylindrical structures. When the upper adjusting rod 41 and the lower adjusting rod 51 respectively extend into the upper through hole and the lower through hole 72, they will respectively push the upper concrete column 61 and the lower concrete column 73 upward and downward, so that the upper concrete column 61 and the lower concrete column 73 respectively extend into the top wall and the bottom wall of the excavated soil body in the pilot tunnel.

[0093] In this way, each concrete column extends into the soil body, and the upper adjusting rods 41 and the upper concrete columns 61 and the lower adjusting rods 51 and the lower concrete columns 73 can also play a role in transmitting the axial soil pressure. When only relying on the upper concrete cushion plate 6 and the lower concrete cushion plate 7 to transmit the axial soil pressure, the actual force transmitted by the concrete cushion plate cannot be calculated. However, through the arrangement of each concrete column, since the force applied by each adjusting rod can be easily calculated, the stress conditions of each concrete column can be clearly understood, which is more convenient for the operator to understand the working conditions.

[0094] Further preferably, as Figure 13 shown, an upper rubber gasket is clamped between the upper concrete cushion plate 6 and the upper pressure plate 4, and a plurality of upper through holes are formed in the upper rubber gasket at positions corresponding to the respective upper adjusting rods 41. A lower rubber gasket 75 is clamped between the lower concrete cushion plate 7 and the lower pressure plate 5, and a plurality of lower through holes are formed in the lower rubber gasket 75 at positions corresponding to the respective lower adjusting rods 51. To achieve stable contact between the upper pressure plate 4 at the top and the upper concrete cushion plate 6 and between the lower pressure plate 5 and the lower concrete cushion plate 7.

[0095] In practical applications, generally, on the top surface of the upper concrete pad 6, upper cast-in-place concrete layers 62 are provided corresponding to the positions of the respective upper steel bars, and on the bottom surface of the lower concrete pad 7, lower cast-in-place concrete layers 74 are provided corresponding to the positions of the respective lower steel bars 71.

[0096] By using each steel bar, after the steel bars are inserted into the soil and the entire support structure is assembled, it can quickly play a role in stable contact and force transmission; through the upper cast-in-place concrete layer 62 and the lower cast-in-place concrete layer 74, after the concrete layer solidifies, it can play a role in force transmission, and the cooperation of each steel bar and the cast-in-place concrete layer can further improve the structural stability. It can be understood that according to the different shapes of the tunnel excavation surface, the shapes of the upper cast-in-place concrete layer 62 and the lower cast-in-place concrete layer 74 may also be different.

[0097] It should be noted that during the disassembly process of the tunnel temporary support structure 100, the upper concrete pad 6 and the lower concrete pad 7 can be removed or retained according to the specific construction environment. Generally, the lower concrete pad 7 will be removed and the upper concrete pad 6 will be retained to play a better role in the initial lining of the top of the tunnel and avoid the situation where the shotcrete on the top of the tunnel cannot be sprayed during the initial support.

[0098] Since the side walls of the pilot tunnels formed during tunnel excavation are all arc-shaped surfaces, in order to better match the arc-shaped side walls of the pilot tunnels, the outer connecting plate 1, the inner connecting plate 2, the middle support plate 3, the upper pressing plate 4, the lower pressing plate 5, the upper concrete pad 6, and the lower concrete pad 7 are all arc-shaped plates. The curvature of each plate body is determined according to the actual situation. Since the sizes of each plate body are designed relatively small, the curvature of each plate body is also relatively small, and they can be spliced into different arc sizes to adapt to various tunnel excavation sizes. Of course, each plate body can also be a flat plate, and the plate bodies can be spliced in a folded line form to meet the usage requirements.

[0099] Furthermore, in order to facilitate the adjustment of each adjusting rod, as Figure 2 , Figure 7 and Figures 10 to 12 shown, a plurality of upper threaded holes 42 penetrating the top and bottom surfaces of the upper pressing plate 4 are provided in the upper pressing plate 4. Each upper adjusting rod 41 is an upper rotating screw rod and is respectively inserted into the corresponding upper threaded hole 42. A plurality of upper operation windows 43 communicating with the respective upper threaded holes 42 are opened on the side surface of the upper pressing plate 4 facing away from the outer connecting plate 1. A plurality of lower threaded holes 52 penetrating the top and bottom surfaces of the lower pressing plate 5 are provided in the lower pressing plate 5. Each lower adjusting rod 51 is a lower rotating screw rod and is respectively inserted into the corresponding lower threaded hole 52. A plurality of lower operation windows 53 communicating with the respective lower threaded holes 52 are opened on the side surface of the lower pressing plate 5 facing away from the outer connecting plate 1. A hollow hole 21 is opened on each inner connecting plate 2, and the hollow hole 21 on the top inner connecting plate 2 can communicate with all the upper operation windows 43, and the hollow hole 21 on the bottom inner connecting plate 2 can communicate with all the lower operation windows 53.

[0100] Generally, each hollow hole 21 is a square hole. On the one hand, it is convenient to rotate each rotating screw rod. On the other hand, it can reduce the weight of each inner connecting plate 2 and save materials. Through the upper operation window 43 and the lower operation window 53, it is convenient for wrench operation. By using a wrench to rotate the upper rotating screw rod, the upper adjusting rod 41 can be extended out of the plate to respectively exert a squeezing effect on the middle support plate 3 at the top and the upper concrete cushion plate 6; by using a wrench to rotate the lower rotating screw rod, the lower adjusting rod 51 can be extended out of the plate to respectively exert a squeezing effect on the middle support plate 3 at the bottom and the lower concrete cushion plate 7. Of course, according to needs, the upper adjusting rod 41 and the lower adjusting rod 51 can also adopt other structural forms as long as they can be conveniently extended. This embodiment is only for illustrative purposes.

[0101] Furthermore, the above-mentioned fixing members 8 are mainly used to realize the anchoring between the external connecting plates 1, the inner connecting plates 2, the middle support plates 3, the upper pressing plates 4 and the lower pressing plates 5 to resist the shear stress between the plates. In this embodiment, as Figure 1 and Figure 4 shown, the fixing member 8 is a reverse screw rod fixed on the external connecting plate 1 with the rod body facing the inner connecting plate 2. The reverse screw rod sequentially passes through the upper pressing plate 4 and the inner connecting plate 2 at the top, sequentially passes through each middle support plate 3 and the corresponding inner connecting plate 2 or sequentially passes through the lower pressing plate 5 and the inner connecting plate 2 at the bottom and is connected by nuts. It can be understood that corresponding mounting holes 81 are provided at the positions corresponding to each reverse screw rod on the upper pressing plate 4, the middle support plate 3, the lower pressing plate 5 and the inner connecting plate 2. In addition, when the position of the hollow hole 21 just corresponds to the position of the reverse screw rod, this part of the reverse screw rod is directly passed through the corresponding hollow hole 21 during installation, and only the middle support plate 3 and the external connecting plate 1 need to be fixed together.

[0102] In practical applications, as Figure 1 and Figures 15 to 19 shown, a plurality of connecting members 9 are detachably fixed on the splicing fixing plate assembly (specifically, between the external connecting plate 1 and the corresponding middle support plate 3 and the corresponding inner connecting plate 2, between the upper pressing plate 4 and the external connecting plate 1 and the inner connecting plate 2 at the top, and between the lower pressing plate 5 and the external connecting plate 1 and the inner connecting plate 2 at the bottom). The outer ends of each connecting member 9 all extend out of the outside of the splicing fixing plate assembly (specifically, the outer ends of each connecting member 9 extend out of the outside of the corresponding external connecting plate 1) and are detachably fixedly connected with the anchor rod member 91, the sealing member 92 or the horizontal support pipe 94. The anchor rod member 91 and the connecting member 9 form a detachable steel anchor rod, which is mainly used to penetrate into the soil to be excavated to reinforce the surrounding rock and can be quickly removed during the later soil excavation process; the sealing member 92 or the horizontal support pipe 94 is mainly used to connect with the connecting member 9 to form an anchor or a horizontal support after the anchor rod member 91 is removed, further improving the stability and safety of the support structure.

[0103] Specifically, in order to facilitate the installation and disassembly of each connecting member 9, asFigure 1 and Figure 15 As shown, the connecting member 9 is of a sleeve structure. A convex ring 901 protrudes outward from the inner end of the sleeve structure. The convex ring 901 is connected to the splicing fixing plate assembly through a plurality of bolts (specifically, connected to the corresponding inner connecting plate 2, the corresponding middle supporting plate 3, and the corresponding outer connecting plate 1, or to the upper inner connecting plate 2, the upper pressing plate 4, and the upper outer connecting plate 1 at the top, or to the lower inner connecting plate 2, the lower pressing plate 5, and the lower outer connecting plate 1 at the bottom).

[0104] It can be understood that, as Figures 3 to 12 shown, perforations 902 are provided at the positions corresponding to each connecting member 9 on the outer connecting plate 1, the inner connecting plate 2, the middle supporting plate 3, the upper pressing plate 4, and the lower pressing plate 5, and a plurality of bolt holes 903 are provided around the outer periphery of each perforation 902. The perforation 902 and the surrounding plurality of bolt holes 903 form a plum blossom-shaped hole, so as to facilitate the insertion of the connecting member 9 and the installation of each bolt. Specifically, the number and position of each perforation 902, as well as the number and position of the installation holes 81 for inserting each reverse screw rod mentioned above, are determined according to actual needs and ensure that the hole positions on each plate body can correspond to each other. In addition, if the position of the hollow hole 21 just corresponds to the connecting member 9, then when this part of the connecting member 9 is fixed with bolts, only the convex ring 901 needs to be fixed together with the middle supporting plate 3 and the outer connecting plate 1, or with the upper pressing plate 4 and the upper outer connecting plate 1, or with the lower pressing plate 5 and the lower outer connecting plate 1.

[0105] More specifically, referring to Figure 1 and Figure 15 , the outer end of the sleeve structure is threadedly connected to the end of the anchor rod member 91. Each anchor rod member 91 is used to be inserted into the corresponding slot holes opened in the soil to be excavated, so as to reinforce the soil to be excavated and improve the structural stability. Generally, the outer wall of the anchor rod member 91 is threadedly connected to the inner wall of the sleeve structure. Any anchor rod in the prior art can be used for the anchor rod member 91, and details will not be described here.

[0106] Referring to Figure 16 , the closing member 92 is of a cylindrical structure with one end open. The open end of the cylindrical structure is threadedly connected to the outer end of the sleeve structure. Generally, the outer wall of the open end of the closing member 92 is threadedly connected to the inner wall of the sleeve structure. When excavating the soil in the anchorage area of the anchor rod member 91 in the later stage, after the anchor rod member 91 is screwed out from the connecting member 9, the closing member 92 can be connected to the outer end of a part of the connecting members 9 to form an anchor.

[0107] Referring to Figure 17 and Figure 18, the outer end of the sleeve structure is threadedly connected with an adapter elbow 93, and the adapter elbow 93 is threadedly connected with the end of the horizontal support pipe 94. Since each plate body is arranged obliquely along the side wall of the pilot tunnel at a certain angle, the adapter elbow 93 is used to facilitate the connection of the connector 9 to the horizontally arranged horizontal support pipe 94. Generally, the adapter elbow 93 includes a horizontal section pipe and an inclined section pipe. The outer wall of the inclined section pipe is threadedly connected with the inner wall of the sleeve structure, and the outer wall of the horizontal section pipe is threadedly connected with the inner wall of the horizontal support pipe 94.

[0108] When excavating the soil body in the anchorage area of the anchor rod member 91, after the anchor rod member 91 is screwed out from the connector 9, if necessary, the outer end of a part of the connector 9 can be connected to the horizontal support pipe 94 to form a horizontal support. For a tunnel constructed by the double-sided pilot tunnel method, as Figure 19 shown, both ends of the horizontal support pipe 94 can be directly connected to the connectors 9 installed in two tunnel temporary support structures 100 arranged on both sides of the pilot tunnel; for a tunnel constructed by the single-sided pilot tunnel method, one end of the horizontal support pipe 94 is connected to the connector 9, and the other end can be directly connected to the side wall of the excavated soil body of the pilot tunnel (it is necessary to make a simple treatment of the side wall of the excavated soil body). Whether to install the closure 92 or the horizontal support pipe 94 on each connector 9 depends on actual needs.

[0109] Furthermore, during the assembly process of the entire temporary support structure, the above-mentioned external plates 1 and the corresponding internal plates 2 are always assembled in alignment in all directions; for each middle support plate 3 and each external plate 1, they are arranged staggeredly from top to bottom, that is, assembled in a circumferential dislocation along the tunnel; for each middle support plate 3 and each external plate 1, there are the following two assembly methods in the extension direction of the tunnel:

[0110] The first: alignment assembly. As Figure 1 , Figure 2 and Figure 9 shown, the plate surface of the middle support plate 3 is aligned with the plate surface of the corresponding external plate 1 along the extension direction of the tunnel. At this time, adjacent two groups of support units only need to be arranged adjacent to each other.

[0111] The second: staggered assembly. As Figure 20 and Figure 24 shown, the plate surface of the middle support plate 3 is arranged in a staggered manner with the plate surface of the corresponding external plate 1 along the extension direction of the tunnel, and in multiple groups of support units, a part of the middle support plate 3 in each group of support units is clamped between the external plate 1 and the internal plate 2 of the adjacent support unit.

[0112] When adopting the above two assembly methods, as Figures 1 to 12 and Figures 20 to 26As shown, the arrangement of the hole positions on each plate body (the above-mentioned mounting holes 81 and each perforation 902) will also change, and the corresponding arrangement of the anchor rod members 91 will also change accordingly, which is specifically determined according to actual needs. The above-mentioned first splicing method is more convenient for disassembly and installation, can flexibly adapt to the excavation line of the tunnel, and the assembly is more flexible and convenient. This method is mostly used in practice; in the above-mentioned second splicing method, the middle support plate 3, the external connection plate 1, and the internal connection plate 2 always maintain a staggered arrangement in the circumferential direction of the tunnel and the extension direction of the tunnel, which can greatly improve the overall stability of the support structure and is suitable for temporary support over a long distance.

[0113] Furthermore, in this embodiment, a method for using the above-mentioned tunnel temporary support structure 100 is also provided, including the following steps:

[0114] S1. According to the cross-sectional shape of the tunnel and the excavation method of the pilot tunnel method, after analyzing and calculating the construction parameters, the upper concrete cushion plate 6 and upper steel bars, as well as the lower concrete cushion plate 7 and lower steel bars 71 of corresponding sizes are fabricated according to the calculation results to ensure that the entire support structure can form a stable contact and force transmission with the surrounding rock after splicing.

[0115] S2. Insert each of the lower steel bars 71 at the bottom of the lower concrete cushion plate 7 into the bottom wall of the excavated soil body at the corner positions of the pilot tunnel, and then assemble and fix them from bottom to top to form an assembled fixed plate component. Specifically, assemble each external connection plate 1, each internal connection plate 2, the lower pressing plate 5, each middle support plate 3, and the upper pressing plate 4 from bottom to top in sequence, and fix them using each fixing member 8 to form the above-mentioned assembled fixed plate component.

[0116] S3. Place the upper concrete cushion plate 6 on the top of the assembled fixed plate component, and insert each upper steel bar into the top wall of the excavated soil body at the corner positions of the pilot tunnel. In step S3, according to actual needs, generally, a part of the soil body can be further excavated from the top wall of the excavated soil body to facilitate the installation of the upper concrete cushion plate 6 and the upper steel bars. Additionally, preferably, during the installation process, a lower rubber gasket 75 can also be placed on the upper surface of the lower concrete cushion plate 7, and an upper rubber gasket can be placed on the lower surface of the upper concrete cushion plate 6 to achieve stable contact between each pressing plate and the corresponding concrete cushion plate.

[0117] S4. Adjust each upper adjusting rod 41 to extend upward and press the upper concrete cushion plate 6; adjust each lower adjusting rod 51 to extend downward and press the lower concrete cushion plate 7; so that the entire tunnel temporary support structure 100 tends to be stable and becomes an integral whole.

[0118] S5. After the initial lining of the tunnel is stabilized, adjust each upper adjusting rod 41 and each lower adjusting rod 51 to retract into the assembled fixing plate assembly to release the extrusion internal force of the support structure; then disassemble the assembled fixing plate assembly from top to bottom. Specifically, disassemble each fixing member 8 from top to bottom in sequence (that is, unscrew the corresponding nuts on each fixing member 8), each external connecting plate 1, each internal connecting plate 2, the lower pressing plate 5, each middle supporting plate 3 and each middle supporting plate 3 to complete the demolition of the temporary support structure 100 of the tunnel, so as to facilitate the subsequent construction for reuse.

[0119] Further preferably, a plurality of upper concrete columns 61 are slidably inserted into a plurality of upper through holes formed in the upper concrete cushion plate 6, and a plurality of lower concrete columns 73 are slidably inserted into a plurality of lower through holes 72 formed in the lower concrete cushion plate 7;

[0120] In step S4, after each upper adjusting rod 41 extends upward and is inserted into the corresponding upper through hole, it pushes the corresponding upper concrete column 61 to extend upward and insert into the top wall of the excavated soil body; after each lower adjusting rod 51 extends downward and is inserted into the corresponding lower through hole 72, it pushes the corresponding lower concrete column 73 to extend downward and insert into the bottom wall of the excavated soil body. In this way, the upper adjusting rod 41 and the lower adjusting rod 51 respectively extend into the corresponding upper through hole and lower through hole 72, which can also effectively improve the effect of the support structure in resisting the lateral earth pressure of the soil body to be excavated; moreover, by using each upper concrete column 61 and each lower concrete column 73, it can also play a role in transmitting the axial soil pressure, making the structure more stable and reliable.

[0121] In practical applications, generally in step S2, a part of each lower steel bar 71 is inserted into the bottom wall of the excavated soil body, and concrete is cast in situ for the part of the lower steel bar 71 between the lower concrete cushion plate 7 and the bottom wall of the excavated soil body to form a lower in-situ concrete layer 74; then each plate body is spliced. In step S3, a part of each upper steel bar is inserted into the top wall of the excavated soil body, and concrete is cast in situ for the part of the upper steel bar between the upper concrete cushion plate 6 and the top wall of the excavated soil body to form an upper in-situ concrete layer 62. Through the setting of each in-situ concrete layer, the stability of the structure can be further ensured.

[0122] More preferably, the following steps are further included between step S1 and step S2:

[0123] S15. Determine the arrangement of a plurality of anchor members 91, and perform grooving treatment on the soil body to be excavated to form a plurality of grooved holes;

[0124] The following steps are further included between step S2 and step S3:

[0125] S25. Connect the ends of multiple anchor rod members 91 to the outer ends of the corresponding connecting members 9, and insert and fix each connecting member 9 in the assembled fixed plate assembly (specifically, insert them respectively between the external plate 1 and the corresponding middle support plate 3 and the corresponding internal connection plate 2, between the upper pressure plate 4 and the top external plate 1 and internal connection plate 2, and between the lower pressure plate 5 and the bottom external plate 1 and internal connection plate 2), and make the outer ends of each connecting member 9 extend out of the outside of the assembled fixed plate assembly, and each anchor rod member 91 is inserted into the corresponding slot hole to reinforce the surrounding rock;

[0126] Between step S4 and step S5, the following steps are also included:

[0127] S45. When excavating the soil body in the anchorage area of each anchor rod member 91, disconnect the corresponding anchor rod member 91 from the corresponding connecting member 9, and then connect the outer ends of some connecting members 9 to a sealing member 92, and connect the outer ends of the other part of the connecting members 9 to a horizontal support pipe 94 to form an anchor or a horizontal support to improve the structural stability.

[0128] In step S5, when disassembling the assembled fixed plate assembly, disassemble each connecting member 9, each sealing member 92 and each horizontal support pipe 94 for easy reuse.

[0129] In summary, the entire tunnel temporary support structure 100 and its usage method have at least the following advantages:

[0130] (1) By assembling the external plates 1, internal connection plates 2 and middle support plates 3, arranging the three layers of steel plates layer by layer, and then using the reverse screws to assemble and fix them, a whole continuous temporary support structure can be formed, and the rapid assembly of the tunnel temporary support structure 100 can be realized;

[0131] Due to the existence of the upper pressure plate 4, lower pressure plate 5, upper concrete cushion plate 6 and lower concrete cushion plate 7, and using the extrusion effect of each adjusting rod, the close contact between the support structure and the surrounding rock can be realized. The concrete cushion plates of different sizes can ensure the stable contact between the end of the support structure and the surrounding rock, thereby further enhancing the safety and flexibility of the support structure, and finally realizing the temporary support effect on the tunnel during the excavation process; As the construction process progresses, when the surrounding rock is stable and the support structure needs to be removed, the extrusion internal force of the temporary support structure can be released by loosening each adjusting rod in each pressure plate, and then the nuts corresponding to the reverse screws on the steel plates can be loosened in turn from top to bottom to remove each steel plate. The removal efficiency is relatively high, and the disassembled external plates 1, internal connection plates 2, upper pressure plate 4, lower pressure plate 5 and each fixing member 8 can be reused to save costs;

[0132] (2) Each anchor rod member 91 can be quickly removed during the construction of the middle pilot tunnel, which can improve the construction efficiency on the one hand and effectively avoid the waste of materials on the other hand;

[0133] (3) Compared with the structure of the traditional shotcrete with steel mesh temporary support, the support structure in this embodiment is conducive to further promoting the industrialization of tunnel construction, ensuring the safety of the construction environment while improving efficiency, reducing the use of concrete at the same time, saving building materials and protecting the environment, and effectively solving the internal support problem during the partial excavation of super-large cross-section tunnels.

[0134] The above are only illustrative specific embodiments of the present invention and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A temporary support structure for a tunnel, characterized in that, It includes multiple groups of support units arranged closely along the extension direction of the tunnel; Each group of the support units includes a splicing fixed plate assembly, an upper concrete cushion plate abutted above the splicing fixed plate assembly, and a lower concrete cushion plate abutted below the splicing fixed plate assembly. Inside the top of the splicing fixed plate assembly, there are multiple upper adjusting rods that can extend upward and abut against the upper concrete cushion plate. Inside the bottom of the splicing fixed plate assembly, there are multiple lower adjusting rods that can extend downward and abut against the lower concrete cushion plate. On the top surface of the upper concrete cushion plate, there are multiple upper steel bars extending upward. On the bottom surface of the lower concrete cushion plate, there are multiple lower steel bars extending downward; The splicing fixed plate assembly in each group of the support units includes multiple outer connecting plates arranged closely from top to bottom, multiple inner connecting plates arranged closely from top to bottom and aligned with the plate surfaces of the respective outer connecting plates, multiple middle support plates arranged closely from top to bottom and clamped between the respective outer connecting plates and inner connecting plates, an upper pressing plate clamped between the outer connecting plate and the inner connecting plate at the top and abutting above the middle support plate at the top, and a lower pressing plate clamped between the outer connecting plate and the inner connecting plate at the bottom and abutting below the middle support plate at the bottom. Between each outer connecting plate and the corresponding middle support plate and the corresponding inner connecting plate, between the upper pressing plate and the outer connecting plate and the inner connecting plate at the top, and between the lower pressing plate and the outer connecting plate and the inner connecting plate at the bottom, they are all detachably fixedly connected through multiple fixing pieces; The outer sides of the respective outer connecting plates are used to abut against the inner wall of the pilot tunnel of the tunnel. The plate surfaces of each middle support plate and each outer connecting plate are staggered from top to bottom. Each of the upper adjusting rods is arranged inside the upper pressing plate, and each of the lower adjusting rods is arranged inside the lower pressing plate. The upper concrete cushion plate abuts above the upper pressing plate, the outer connecting plate at the top, and the inner connecting plate at the top. The lower concrete cushion plate abuts below the lower pressing plate, the outer connecting plate at the bottom, and the inner connecting plate at the bottom; At the positions corresponding to the respective upper adjusting rods on the upper concrete cushion plate, multiple upper through holes are opened, and each upper adjusting rod can extend into the corresponding upper through hole. At the positions corresponding to the respective lower adjusting rods on the lower concrete cushion plate, multiple lower through holes are opened, and each lower adjusting rod can extend into the corresponding lower through hole.

2. The temporary support structure for a tunnel according to claim 1, wherein Upper concrete columns are slidably inserted into each of the upper through holes, and lower concrete columns are slidably inserted into each of the lower through holes.

3. The temporary support structure for a tunnel according to claim 1, wherein An upper rubber gasket is clamped between the upper concrete cushion plate and the upper pressing plate, and multiple upper through holes are opened in the upper rubber gasket at the positions corresponding to the respective upper adjusting rods. A lower rubber gasket is clamped between the lower concrete cushion plate and the lower pressing plate, and multiple lower through holes are opened in the lower rubber gasket at the positions corresponding to the respective lower adjusting rods.

4. The temporary support structure for a tunnel according to claim 1, wherein On the top surface of the upper concrete cushion plate, upper cast-in-place concrete layers are provided corresponding to the positions of the upper steel bars, and on the bottom surface of the lower concrete cushion plate, lower cast-in-place concrete layers are provided corresponding to the positions of the lower steel bars.

5. The temporary support structure for a tunnel according to claim 1, wherein the external connection plate, the internal connection plate, the middle support plate, the upper pressing plate, the lower pressing plate, the upper concrete cushion plate and the lower concrete cushion plate are all arc-shaped plates.

6. The temporary support structure for a tunnel according to claim 1, wherein a plurality of upper threaded holes penetrating through the top surface and the bottom surface thereof are provided in the upper pressing plate, each of the upper adjusting rods is an upper rotating screw rod and is respectively inserted into the corresponding upper threaded holes, and a plurality of upper operation windows communicating with the respective upper threaded holes are opened on the side surface of the upper pressing plate facing away from the external connection plate; a plurality of lower threaded holes penetrating through the top surface and the bottom surface thereof are provided in the lower pressing plate, each of the lower adjusting rods is a lower rotating screw rod and is respectively inserted into the corresponding lower threaded holes, and a plurality of lower operation windows communicating with the respective lower threaded holes are opened on the side surface of the lower pressing plate facing away from the external connection plate; a hollow hole is opened on each of the internal connection plates, and the hollow hole on the top internal connection plate can communicate with all the upper operation windows, and the hollow hole on the bottom internal connection plate can communicate with all the lower operation windows.

7. The temporary support structure for a tunnel according to claim 1, wherein the fixing member is a reverse screw rod fixed on the external connection plate and with the rod body facing the internal connection plate, and the reverse screw rod sequentially passes through the upper pressing plate and the top internal connection plate, sequentially passes through each of the middle support plates and the corresponding internal connection plate or sequentially passes through the lower pressing plate and the bottom internal connection plate and is connected by nuts.

8. The temporary support structure for a tunnel according to claim 1, wherein a plurality of connecting members are detachably fixed and inserted on the splicing fixing plate assembly, and the outer ends of each of the connecting members extend out of the outer side of the splicing fixing plate assembly and are detachably and fixedly connected with an anchor rod member, a sealing member or a horizontal support pipe.

9. The temporary support structure for a tunnel according to claim 8, wherein the connecting member is a sleeve structure, and a convex ring protrudes outwards at the inner end of the sleeve structure, and the convex ring is connected with the splicing fixing plate assembly through a plurality of bolts.

10. The temporary support structure for a tunnel according to claim 9, wherein the outer end of the sleeve structure is threadedly connected with the end of the anchor rod member, and each of the anchor rod members is used for being inserted into a corresponding slot hole opened on the soil to be excavated.

11. The temporary support structure for a tunnel according to claim 9, wherein the sealing member is a cylindrical structure with one end open, and the open end of the cylindrical structure is threadedly connected with the outer end of the sleeve structure.

12. The temporary support structure for a tunnel according to claim 9, wherein a connecting elbow is threadedly connected to the outer end of the sleeve structure, and the connecting elbow is threadedly connected with the end of the horizontal support pipe.

13. The temporary support structure for a tunnel according to claim 1, wherein The plate surface of the middle support plate is arranged in alignment with the plate surface of the corresponding external connection plate along the extension direction of the tunnel; or The plate surface of the middle support plate is arranged in dislocation with the plate surface of the corresponding external connection plate along the extension direction of the tunnel, and in multiple groups of the support units, a part of the middle support plate in each group of the support units is clamped between the external connection plate and the internal connection plate of the adjacent support units.

14. A method for using a temporary tunnel support structure according to any one of claims 1-13, characterized in that, It includes the following steps: S1. According to the cross-sectional shape of the tunnel and the excavation method of the pilot tunnel method, fabricate the upper concrete cushion plate, the upper steel bars, the lower concrete cushion plate and the lower steel bars with corresponding dimensions; S2. Insert each of the lower steel bars at the bottom of the lower concrete cushion plate into the bottom wall of the excavated soil mass at the corner of the pilot tunnel, and then assemble and fix them from bottom to top to form the spliced fixed plate assembly; S3. Place the upper concrete cushion plate on the top of the spliced fixed plate assembly, and insert each of the upper steel bars into the top wall of the excavated soil mass at the corner of the pilot tunnel; S4. Adjust each of the upper adjusting rods to extend upward and press the upper concrete cushion plate; adjust each of the lower adjusting rods to extend downward and press the lower concrete cushion plate; S5. After the primary lining of the tunnel is stable, adjust each of the upper adjusting rods and each of the lower adjusting rods to retract into the spliced fixed plate assembly, and then disassemble the spliced fixed plate assembly from top to bottom to complete the demolition of the temporary support structure of the tunnel.

15. The method for using the temporary support structure of the tunnel according to claim 14, characterized in that A plurality of upper concrete columns are slidably inserted into a plurality of upper through holes formed in the upper concrete cushion plate, and a plurality of lower concrete columns are slidably inserted into a plurality of lower through holes formed in the lower concrete cushion plate; In step S4, after each of the upper adjusting rods extends upward, it is inserted into the corresponding upper through hole, and pushes the corresponding upper concrete column to extend upward and insert into the top wall of the excavated soil mass; After each of the lower adjusting rods extends downward, it is inserted into the corresponding lower through hole, and pushes the corresponding lower concrete column to extend downward and insert into the bottom wall of the excavated soil mass.

16. The method for using the temporary support structure of the tunnel according to claim 14, characterized in that In step S2, a part of each of the lower steel bars is inserted into the bottom wall of the excavated soil mass, and concrete is cast in situ on the part of the lower steel bars between the lower concrete cushion plate and the bottom wall of the excavated soil mass to form a lower in-situ concrete layer; In step S3, a part of each of the upper steel bars is inserted into the top wall of the excavated soil mass, and concrete is cast in situ on the part of the upper steel bars between the upper concrete cushion plate and the top wall of the excavated soil mass to form an upper in-situ concrete layer.

17. The method for using the temporary support structure of the tunnel according to claim 14, characterized in that The following steps are further included between step S1 and step S2: S15. Determine the arrangement of a plurality of anchor members, and perform grooving treatment on the soil mass to be excavated to form a plurality of groove holes; The following steps are further included between step S2 and step S3: S25. Connect the ends of multiple anchor rod members to the outer ends of the corresponding connecting members, insert and fix each connecting member in the splicing fixing plate assembly, and make the outer ends of each connecting member extend out of the outer side of the splicing fixing plate assembly, and each anchor rod member is inserted into the corresponding slot hole; Between step S4 and step S5, the following steps are further included: S45. When excavating the soil body in the anchorage area of each anchor rod member, disassemble the corresponding anchor rod member and the corresponding connecting member, and then connect the outer ends of some of the connecting members to a sealing member, and connect the outer ends of the other part of the connecting members to a horizontal support pipe; In step S5, when disassembling the splicing fixing plate assembly, disassemble each connecting member, each sealing member and each horizontal support pipe.

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