Tension-compression conversion yielding supporting structure and supporting method

Abstract

The invention belongs to the technical field of tunnel engineering, and particularly relates to a tension-compression conversion yielding supporting structure and a supporting method. A tension-compression conversion yielding supporting structure comprises two arch frame structures and a yielding module, the yielding module comprises two base plates, a plurality of fastening assemblies and a concrete filled steel tube short column between the two base plates, the base plates are fixedly connected with the arch frame structures, the fastening assemblies are used for connecting and fastening the two base plates, a partition plate assembly is further arranged between the two base plates, and the partition plate assembly is used for connecting and fastening the two base plates. The concrete-filled steel tube short column comprises a steel tube, two ends of the steel tube are fixedly connected with the center of the base plate, a reinforcing mesh is fixedly arranged on the inner wall of the steel tube, fiber concrete is filled in the steel tube, and annular slits are arranged on the upper portion and the lower portion of the steel tube respectively. The pressure supporting structure is simple in structural design, capable of being constructed in an assembled mode, easy and convenient to install and operate and low in cost, during use, the pressure yielding modules achieve three-stage stress due to the fact that the steel pipes restrain the fiber concrete short columns, and deformation and damage of a tunnel are effectively prevented.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel engineering, and in particular relates to a tension-compression conversion yielding support structure and a support method. Background Art

[0002] As China's infrastructure continues to advance and the railway system continues to improve, due to the large number of mountains in China and the complex terrain and geological conditions, it is inevitable to cross unfavorable geological areas during railway planning, especially in high-stress soft rock areas. The tunnels that pass through not only increase the difficulty of construction, but also often suffer large deformation damage. According to the causes and characteristics of deformation, it is necessary to prevent and control it by setting up support structures.

[0003] In the development of tunnel support, there are mainly two different support concepts: traditional rigid support and yield support. Traditional rigid support is achieved by increasing the strength of the steel arch frame itself, the layout density, and the strength of the lining material. However, due to the large rigidity of the traditional rigid support structure, the deformation of the surrounding rock is controlled only by increasing the support stiffness. The allowable deformation of the support structure is small and the deformation energy in the surrounding rock cannot be further released, resulting in the surrounding rock around the tunnel still maintaining a high stress level. Therefore, various types of large deformation accidents are easily caused during the secondary stress redistribution of the surrounding rock after tunnel excavation. Subsequently, the yield support structure that actively releases the surrounding rock stress and gives the surrounding rock energy absorption and energy dissipation concepts came into being.

[0004] The yielding support structure can release the deformation energy accumulated in the surrounding rock through a reasonable preset support deformation, combining rigidity and flexibility. After the surrounding rock is secondary balanced, the support system still has the bearing capacity. However, the existing yielding support structure is relatively complex in design and difficult to construct, making it difficult to popularize. Summary of the invention

[0005] In view of the above problems, the purpose of the present invention is to provide a tension-compression conversion compression support structure and support method. The compression support structure has a simple design, can be assembled for construction, is easy to install and operate, and has low cost. When in use, the compression module can achieve three-stage force due to the setting of steel pipe constrained fiber concrete, thereby effectively preventing deformation and damage of the tunnel.

[0006] The technical solution of the present invention is: a tension-compression conversion yielding support structure, comprising two arch structures and a yielding module connected between the two arch structures, the yielding module comprising two pads, a plurality of fastening components and a steel tube concrete short column between the two pads, the pad is fixedly connected to the arch structure, the fastening component is used to connect and fasten the two pads, a partition component is also provided between the two pads, the steel tube concrete short column comprises a steel pipe, both ends of the steel pipe are respectively fixedly connected to the center position of the pad, a steel mesh is fixedly provided on the inner wall of the steel pipe, the steel pipe is filled with fiber concrete, and annular slits are respectively provided on the upper and lower parts of the steel pipe.

[0007] The fastening assembly is an anchor fastening assembly or a cable fastening assembly, and the anchor fastening assembly comprises a nut and an anchor.

[0008] The anchor rod fastening assembly is arranged inside or outside the steel tube concrete short column.

[0009] The partition assembly comprises a partition, the partition is fixedly connected to the backing plate, and a partition stiffening plate is provided on the partition.

[0010] The partitions are fixedly connected to the backing plate, the partitions are staggered on the backing plate, and the partitions are welded to the backing plate.

[0011] The shape of the pad is rectangular, square or circular.

[0012] The width of the annular slit is 10 mm to 20 mm.

[0013] The fiber concrete is low elastic modulus fiber concrete, which is not higher than 34500MPa.

[0014] A tension-compression conversion yielding support method, using the tension-compression conversion yielding support structure as described above, comprises the following steps: S1: According to the design requirements, the pressure relief module is prefabricated in the factory. The two pads are connected by fastening components. The partition components are arranged on both sides of the pads. The steel pipe and the pad are connected by welding. The steel mesh is placed between the steel pipe and the fiber concrete. The steel mesh is spot welded to the inner wall of the steel pipe. After the fiber concrete is cured, it can be directly placed between the steel mesh and the pad. S2: Connect the prefabricated pressure-relief modules in the factory to the arch structure, specifically by welding the pads to the arch structure to complete the installation of the pressure-relief support structure.

[0015] The technical effects of the present invention are: 1. The compression module of the present invention is structurally designed and can be prefabricated in a factory, with on-site assembly construction, simple installation operation and low cost; 2. The steel tube concrete short column of the compression module of the present invention realizes three-stage force due to the setting of the annular slit, which effectively prevents deformation and damage of the tunnel; 3. The steel mesh of the present invention is placed between the steel tube and the fiber concrete to avoid large pieces of concrete from collapsing and fix the position of the steel tube; 4. The partition assembly of the present invention is staggeredly welded to the pad up and down to bear the soil side pressure.

[0016] The following is a further description with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of a tension-compression conversion compression-yielding support structure according to an embodiment of the present invention.

[0018] Figure 2The figure is a schematic diagram of the middle cross-sectional structure of a tension-compression conversion compression-yielding supporting structure according to an embodiment of the present invention.

[0019] Figure 3 This is a front view of a tension-compression conversion compression support structure according to an embodiment of the present invention.

[0020] Figure numerals: 1-arch structure, 2-base plate, 3-fastening assembly, 31-nut, 32-anchor rod, 4-fiber concrete, 5-partition assembly, 51-partition, 52-partition stiffening plate, 6-steel pipe, 7-steel mesh. DETAILED DESCRIPTION Example 1

[0021] like Figure 1~Figure 3 As shown, a tension-compression conversion yielding support structure comprises two arch structures 1 and a yielding module connected between the two arch structures 1, the yielding module comprises two pads 2, a plurality of fastening components 3 and a steel tube concrete short column between the two pads 2, the pads 2 are fixedly connected to the arch structures 1, the fastening components 3 are used to connect and fasten the two pads 2, a partition component 5 is also provided between the two pads 2, the steel tube concrete short column comprises a steel pipe 6, both ends of the steel pipe 6 are respectively fixedly connected to the center position of the pads 2, a steel mesh 7 is fixedly provided on the inner wall of the steel pipe 6, the steel pipe 6 is filled with fiber concrete 4, and annular slits are respectively provided on the upper and lower parts of the steel pipe 6.

[0022] During actual use, the present invention prefabricates the pressure-releasing module in the factory according to the design requirements, the two pads 2 are connected by the fastening assembly 3, the partition assembly 5 is arranged on both sides of the pad 2, the steel pipe 6 is connected to the pad 2 by welding, the steel mesh 7 is placed between the steel pipe 6 and the fiber concrete 4, the steel mesh 7 is spot welded to the inner wall of the steel pipe 6, and the fiber concrete 4 can be directly placed between the steel mesh 7 and the pad 2 after curing; the prefabricated pressure-releasing module in the factory is connected to the arch frame structure 1, specifically by welding the pad 2 to the arch frame structure 1, to complete the installation of the pressure-releasing support structure. When in use, the pressure-releasing support structure realizes compression deformation by constraining the fiber concrete short column by the steel pipe, and the deformation is divided into three stages: in the first stage, only the fiber concrete bears the pressure, and the fiber concrete undergoes lateral deformation under the pressure until it contacts the steel pipe. In this stage, the deformation is large and the force is small; in the second stage, the steel pipe plays a restraining role, and the load continues to rise, but the deformation speed slows down; in the third stage, the steel pipe and the fiber concrete jointly bear the pressure, and the deformation is small in this stage. The present invention allows the compression module to achieve three-stage stress due to the arrangement of the steel tube-constrained fiber concrete short columns, thereby effectively preventing deformation and damage of the tunnel. Example 2

[0023] Preferably, on the basis of Embodiment 1, in this embodiment, the fastening assembly 3 is an anchor fastening assembly or a cable fastening assembly, and the anchor fastening assembly includes a nut 31 and an anchor 32 .

[0024] In actual use, the fastening assembly 3 of the present invention is an anchor fastening assembly or a cable fastening assembly, and the anchor fastening assembly includes a nut 31 and an anchor 32, and tensile deformation is achieved through the anchor assembly. Example 3

[0025] Preferably, based on Example 1 or Example 2, in this embodiment, the anchor rod fastening assembly is arranged inside or outside the steel tube concrete short column.

[0026] During actual use, the anchor rod fastening assembly of the present invention is arranged inside or outside the steel tube concrete short column, and tensile deformation is achieved through the anchor rod assembly. Example 4

[0027] Preferably, on the basis of Example 1 or Example 3, in this embodiment, the partition assembly 5 includes a partition 51, the partition 51 is fixedly connected to the pad 2, and a partition stiffening plate 52 is provided on the partition 51.

[0028] In actual use, the partition assembly 5 of the present invention includes a partition 51, and the partition 51 is fixedly connected to the pad 2. The partition 51 is provided with a partition stiffening plate 52 for bearing the soil side pressure. Example 5

[0029] Preferably, on the basis of Example 1 or Example 4, in this embodiment, the partitions 51 are fixedly connected to the pad 2, the partitions 51 are staggered on the pad 2, and the partitions 51 are welded to the pad 2.

[0030] In actual use, the partitions 51 of the present invention are fixedly connected to the pad 2, the partitions 51 are staggered on the pad 2, and the partitions 51 are welded to the pad 2 for easy connection. Example 6

[0031] Preferably, based on Embodiment 1, in this embodiment, the shape of the pad 2 is rectangular, square or circular.

[0032] In actual use, the shape of the pad 2 of the present invention is rectangular or square, which is convenient for application in different construction conditions. Example 7

[0033] Preferably, based on Example 1 or Example 6, in this embodiment, the width of the annular slit is 10 mm to 20 mm.

[0034] In actual use, the width of the annular slit described in the present invention is 10mm~20mm. When in use, the compression support structure realizes compression deformation through the steel tube constraining the fiber concrete short column. The deformation is divided into three stages: in the first stage, only the fiber concrete bears the pressure, and the fiber concrete undergoes lateral deformation under the pressure until it contacts the steel tube. In this stage, the deformation is large and the force is small; in the second stage, the steel tube plays a restraining role and the load continues to rise, but the deformation speed slows down; in the third stage, the steel tube and fiber concrete jointly bear the compression, and the deformation is small in this stage. The steel tube concrete short column of the compression module of the present invention realizes three-stage force due to the setting of the steel tube constraining the fiber concrete short column, which effectively prevents deformation and damage of the tunnel. Example 8

[0035] Preferably, on the basis of Example 1 or Example 6, in this embodiment, the fiber concrete 4 is a low elastic modulus fiber concrete, which is not higher than 34500 MPa.

[0036] In actual use, the fiber concrete 4 of the present invention is a low elastic modulus fiber concrete, which has large deformation and is not easily crushed. Example 9

[0037] A tension-compression conversion yielding support method, using the tension-compression conversion yielding support structure as described above, comprises the following steps: S1: According to the design requirements, the pressure relief module is prefabricated in the factory, the two pads 2 are connected by the fastening assembly 3, the partition assembly 5 is arranged on both sides of the pad 2, the steel pipe 6 is connected to the pad 2 by welding, the steel mesh 7 is placed between the steel pipe 6 and the fiber concrete 4, and the steel mesh 7 is spot welded to the inner wall of the steel pipe 6. After the fiber concrete 4 is cured or the strength reaches 75%, it can be directly placed between the steel mesh 7 and the pad 2; S2: Connect the prefabricated pressure-relief module in the factory to the arch structure 1, specifically by welding the pad 2 to the arch structure 1 to complete the installation of the pressure-relief support structure.

[0038] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A tension-compression conversion yielding support structure, characterized in that: The invention comprises two arch structures (1) and a pressure-relief module connected between the two arch structures (1), wherein the pressure-relief module comprises two pads (2), a plurality of fastening components (3) and a steel tube concrete short column between the two pads (2), wherein the pads (2) are fixedly connected to the arch structures (1), the fastening components (3) are used to connect and fasten the two pads (2), a partition component (5) is further provided between the two pads (2), and the steel tube concrete short column comprises a steel tube (6), wherein both ends of the steel tube (6) are respectively fixedly connected to the center of the pads (2), a steel mesh (7) is fixedly provided on the inner wall of the steel tube (6), the steel tube (6) is filled with fiber concrete (4), and the upper and lower parts of the steel tube (6) are respectively provided with annular slits.

2. A tension-compression conversion compression support structure according to claim 1, characterized in that: The fastening assembly (3) is an anchor rod fastening assembly or a cable fastening assembly, and the anchor rod fastening assembly comprises a nut (31) and an anchor rod (32).

3. A tension-compression conversion yielding support structure according to claim 2, characterized in that: The anchor rod fastening assembly is arranged inside or outside the steel tube concrete short column.

4. According to claim 1, the tension-compression conversion yielding support structure is characterized in that: The partition assembly (5) comprises a partition (51), the partition (51) being fixedly connected to the backing plate (2), the partition (51) being arranged vertically to the backing plate (2), and a partition stiffening plate (52) being provided on the partition (51).

5. According to claim 1, the tension-compression conversion yielding support structure is characterized in that: The partition plates (51) are fixedly connected to the backing plate (2); the partition plates (51) are arranged in a staggered manner on the backing plate (2); and the partition plates (51) and the backing plate (2) are welded.

6. The tension-compression conversion compression support structure according to claim 1, characterized in that: The pad (2) is in the shape of a rectangle, a square or a circle.

7. The tension-compression conversion compression support structure according to claim 1, characterized in that: The width of the annular slit is 10 mm to 20 mm.

8. The tension-compression conversion compression-yielding support structure according to claim 1, characterized in that: The fiber concrete (4) is a low elastic modulus fiber concrete, and the elastic modulus is not higher than 34500 MPa.

9. A tension-compression conversion yielding support method, using a tension-compression conversion yielding support structure as claimed in claim 1, characterized in that: The following steps are involved: S1: According to the design requirements, a pressure relief module is prefabricated in a factory, two pads (2) are connected by a fastening assembly (3), a partition assembly (5) is arranged on both sides of the pad (2), the steel pipe (6) and the pad (2) are connected by welding, a steel mesh (7) is placed between the steel pipe (6) and the fiber concrete (4), the steel mesh (7) is spot welded to the inner wall of the steel pipe (6), and the fiber concrete (4) can be directly placed between the steel mesh (7) and the pad (2) after curing; S2: Connecting the prefabricated pressure-relief module in the factory to the arch structure (1), specifically by welding the pad (2) to the arch structure (1), to complete the installation of the pressure-relief support structure.

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