A constant resistance pressure-yielding primary support joint device suitable for soft rock large deformation tunnels

Abstract

The utility model relates to the technical field of tunnel primary support structure, and discloses a constant resistance and pressure-yielding primary support joint device suitable for soft rock large deformation tunnels. The constant resistance and pressure-yielding primary support joint device is installed on the primary support steel frame unit and is located at each I-beam joint of the primary support steel frame unit, and the number of the constant resistance and pressure-yielding primary support joint device is several; each constant resistance and pressure-yielding primary support joint device includes a connecting steel plate bolted to the I-beam joint steel plate, and a plug-in sleeve and a plug-in rod mutually plugged in between the connecting steel plates; a tunnel deformation shear structure is formed on the plug-in rod, and the tunnel deformation shear structure is destroyed when the plug-in rod moves into the plug-in sleeve. When the tunnel passes through the soft rock large deformation section, the constant resistance and pressure-yielding primary support joint device can provide continuous and constant pressure-yielding resistance, so that the surrounding rock can undergo sufficient convergence deformation, and realize the "release first and then resistance, soft first and then hard" management process of the soft rock large deformation tunnel.

Description

Technical Field

[0001] The utility model relates to the technical field of tunnel primary support structures, in particular to a constant resistance and pressure-yielding primary support joint device suitable for soft rock large deformation tunnels. Background Art

[0002] As my country's expressways continue to extend to the western mountainous areas, the geological environment faced by tunnels has become increasingly complex, and large deformation of soft rock with high ground stress is one of them. When a tunnel passes through a large deformation section, it is very easy to cause surrounding rock intrusion, support failure, and collapse accidents. The main reason is that the traditional primary support steel frame cannot actively give way, and the deformation stress of the surrounding rock cannot be effectively released. Based on the shortcomings of traditional steel frames, studying a primary support steel frame joint that coordinates deformation and actively gives way is a problem worth thinking about and urgently needs to be solved. Utility Model Content

[0003] Based on the current problems, the utility model provides a constant resistance and pressure-relieving initial support joint device suitable for soft rock large deformation tunnels. When the tunnel passes through the soft rock large deformation section, the initial support steel frame joint actively releases pressure, so as to achieve coordinated deformation of the initial support and the surrounding rock, and the surrounding rock pressure can be effectively released.

[0004] The technical solution adopted by the utility model is:

[0005] A constant resistance and pressure-yielding primary support joint device suitable for a soft rock large deformation tunnel, wherein the constant resistance and pressure-yielding primary support joint device is installed on a primary support steel frame unit and is located at each I-beam joint of the primary support steel frame unit, and the number of the constant resistance and pressure-yielding primary support joint device is several; each constant resistance and pressure-yielding primary support joint device comprises a connecting steel plate bolted to the I-beam joint steel plate, and a plug-in sleeve and a plug-in rod plugged into each other between the connecting steel plates; a tunnel deformation shear structure is formed on the plug-in rod, and the tunnel deformation shear structure is destroyed when the plug-in rod moves into the plug-in sleeve.

[0006] Furthermore, the connecting steel plates include a first connecting steel plate and a second connecting steel plate, both of which are rectangular steel plates, and through holes are provided at the four corners of the connecting steel plates to cooperate with the I-beam joint steel plate bolts.

[0007] Furthermore, the plug-in sleeve is a hollow cylindrical structure, one end of which is fixedly connected to the connecting steel plate, and the other end forms a cavity that cooperates with the plug-in rod.

[0008] Furthermore, the plug-in rod is a cylindrical rod body, one end of which is fixedly connected to the connecting steel plate; the plug-in rod includes a tunnel deformation shear structure section and an insertion section, the insertion section can be inserted into the plug-in sleeve, and the tunnel deformation shear structure section is located outside the plug-in sleeve.

[0009] Furthermore, the tunnel deformation shear structure is an external thread on the plug-in rod, and the end face of the external thread abuts against the end face of the plug-in sleeve.

[0010] Furthermore, the plug-in portion between the plug-in rod and the plug-in sleeve is interference fit.

[0011] The beneficial effects of the utility model are:

[0012] The constant resistance and pressure-yielding primary support joint device is installed on the primary support steel frame unit and is located at each I-beam joint of the primary support steel frame unit; by utilizing the tunnel deformation shear structure on the plug-in rod of each constant resistance and pressure-yielding primary support joint device in conjunction with the plug-in sleeve, when the tunnel passes through a soft rock large deformation section, the constant resistance and pressure-yielding primary support joint device produces shear failure, providing continuous and constant pressure-yielding resistance, and allowing the surrounding rock to undergo sufficient convergent deformation, thereby realizing the "release first, then resistance, soft first, then hard" management process for soft rock large deformation tunnels. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is the installation position diagram of the constant resistance pressure-yielding primary support joint device of the utility model;

[0014] Figure 2 This is a schematic diagram of the overall structure of the constant resistance pressure-yielding primary support joint device of the utility model;

[0015] Figure 3 This is a schematic diagram of the disassembled structure of the constant resistance pressure-yielding primary support joint device of the utility model;

[0016] Figure 1 —3, 1—constant resistance pressure-relieving primary support joint device, 2—primary support steel frame unit, 3—first connecting steel plate, 4—second connecting steel plate, 5—plug-in rod, 6—plug-in sleeve, 7—through hole, 8—cavity, 9—external thread, 10—insertion section. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings of the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] For ease of description, spatially relative terms such as "upper," "lower," "left," and "right" may be used herein to describe the relationship of one element or feature shown in a figure to another element or feature. It should be understood that, in addition to the orientation shown in the processing figure, the spatial terms are intended to include different orientations of the device in use or operation. For example, if the device in the figure is inverted, elements described as being "below" other elements or features will be defined as being "above" the other elements or features. Therefore, the exemplary term "below" can include both upper and lower orientations. The device can be positioned in other ways, and the spatially relative descriptions used herein can be interpreted accordingly.

[0019] This embodiment provides a constant resistance pressure-yielding primary support joint device suitable for soft rock large deformation tunnels; Figure 1 As shown, the constant resistance pressure relief primary support joint device 1 is installed on the primary support steel frame unit 2 and is located at each I-beam joint of the primary support steel frame unit 2. The number of constant resistance pressure relief primary support joint devices 1 installed depends on the number of I-beams constituting the primary support steel frame unit 2. In this embodiment, there are nine of them. The installation direction can be based on the construction requirements. Figure 2 and Figure 3 As shown, each constant resistance pressure-relieving primary support joint device includes a first connecting steel plate 3 and a second connecting steel plate 4 bolted to the I-beam joint steel plate, and a plug-in sleeve 6 and a plug-in rod 5 inserted into each other between the first connecting steel plate 3 and the second connecting steel plate 4; at the same time, a tunnel deformation shear structure is formed on the plug-in rod 5.

[0020] Further, such as Figure 2 and Figure 3 As shown, in this embodiment, the first connecting steel plate 3 and the second connecting steel plate 4 are rectangular steel plates. Considering the connection with the end of the I-beam, through holes 7 are set at the four corners of the first connecting steel plate 3 and the second connecting steel plate 4 so as to be bolted with the I-beam joint steel plate. The plug-in sleeve 6 in this embodiment adopts a hollow cylindrical structure, one end of which is welded and fixed to the second connecting steel plate 4, and the other end forms a cavity 8 for plugging with the plug-in rod 5. The plug-in rod 5 is a cylindrical rod body, and one end of the plug-in rod 5 is welded and fixed to the first connecting steel plate 3; the plug-in rod 5 includes a tunnel deformation shear structure section and an insertion section 10. The tunnel deformation shear structure section is located outside the plug-in sleeve 6, and an external thread 9 with a diameter greater than the inner diameter of the plug-in sleeve 6 is formed thereon, and the insertion section 10 can be inserted into the plug-in sleeve 6. Of course, the plug-in sleeve 6 and the plug-in rod 5 can also adopt other shapes, such as: a rectangular tube body and a rectangular rod body; in addition, the tunnel deformation shear structure can also use a plurality of annular bodies welded by electric welding to replace the external thread 9.

[0021] It should be noted that the insertion section 10 of the plug rod 5 in this embodiment is slightly larger than the inner diameter of the plug sleeve 6, so that an interference fit is formed during plugging; the purpose of forming the interference fit is, first, to increase the stability of the connection between the I-beams of the primary support steel frame unit 2; second, to generate a large friction force when the plug rod 5 moves into the plug sleeve 6. The working principle of the constant resistance pressure primary support joint device is as follows:

[0022] When the tunnel passes through a large deformation section of soft rock, the surrounding rock undergoes convergence deformation after tunnel excavation, and the primary support steel frame unit 2 undergoes circumferential contraction, thereby squeezing the constant resistance yielding primary support joint device. When the constant resistance yielding primary support joint device is subjected to pressure, the plug-in rod 5 first overcomes the friction force and moves into the plug-in sleeve 6; when the pressure further increases, the external thread 9 on the tunnel deformation shear structure section of the plug-in rod 5 abuts against the end face of the plug-in sleeve 6 and is sheared by the end face of the plug-in sleeve 6, while the plug-in rod 5 moves further into the plug-in sleeve 6. Since the external thread 9 is a continuous structure, during the shearing process, the constant resistance yielding primary support joint device can provide continuous and constant yielding resistance, providing conditions for the support and convergence deformation of the surrounding rock.

[0023] When the surrounding rock converges and deforms stably, the end face of the plug sleeve 6 stops shearing the external thread 9, thereby providing a constant support force for the surrounding rock. In extreme cases, when all the external threads 9 on the tunnel deformation shearing structure section of the plug rod 5 are sheared, the first connecting steel plate 3 connected to the plug rod 5 moves to the end face of the plug sleeve 6, and the plug rod 5 can no longer be sheared. At this time, the plug rod 5 cannot continue to move, thereby preventing the surrounding rock from further deformation, and realizing the "first release and then resistance, first soft and then hard" treatment process for soft rock large deformation tunnels.

[0024] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A constant resistance pressure-yielding primary support joint device suitable for soft rock large deformation tunnels, characterized by: The constant resistance and pressure-relieving primary support joint device is installed on the primary support steel frame unit and is located at each I-beam joint of the primary support steel frame unit. There are several of them. Each constant resistance and pressure-relieving primary support joint device includes a connecting steel plate bolted to the I-beam joint steel plate, and a plug-in sleeve and a plug-in rod that are plugged into each other between the connecting steel plates. A tunnel deformation shear structure is formed on the plug-in rod, and the tunnel deformation shear structure is destroyed when the plug-in rod moves into the plug-in sleeve.

2. The constant resistance and pressure-yielding primary support joint device suitable for soft rock large deformation tunnels according to claim 1 is characterized in that: The connecting steel plates include a first connecting steel plate and a second connecting steel plate. Both the first connecting steel plate and the second connecting steel plate are rectangular steel plates, and through holes for connecting with I-beam joint steel plates by bolts are provided at the four corners of the connecting steel plates.

3. The constant resistance pressure-yielding primary support joint device suitable for soft rock large deformation tunnels according to claim 1 is characterized in that: The plug-in sleeve is a hollow cylindrical structure, one end of which is fixedly connected to the connecting steel plate, and the other end forms a cavity for plugging in with the plug-in rod.

4. The constant resistance and pressure-yielding primary support joint device suitable for soft rock large deformation tunnels according to claim 1 is characterized in that: The plug-in rod is a cylindrical rod body, one end of which is fixedly connected to the connecting steel plate; the plug-in rod includes a tunnel deformation shearing structure section and an insertion section, the insertion section can be inserted into the plug-in sleeve, and the tunnel deformation shearing structure section is located outside the plug-in sleeve.

5. The constant resistance and pressure-yielding primary support joint device suitable for soft rock large deformation tunnels according to claim 1 is characterized in that: The tunnel deformation shearing structure is an external thread on the plug-in rod, and the end face of the external thread abuts against the end face of the plug-in sleeve.

6. The constant resistance and pressure-yielding primary support joint device suitable for soft rock large deformation tunnels according to claim 1 is characterized in that: The insertion portion between the insertion rod and the insertion sleeve is interference fit.

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