A pressure-relieving and energy-absorbing steel arch frame suitable for tunnels with large surrounding rock deformation

Abstract

The present invention belongs to the technical field of tunnel support, and provides a pressure-absorbing steel arch frame suitable for tunnels with large deformation of surrounding rocks, including: a top support section and an energy-absorbing assembly, the top support section corresponds to the arch crown and arch waist of the tunnel, the top support section is divided into a left support section and a right support section, the lower ends of the left support section and the right support section are provided with a bottom support section, and the bottom support section corresponds to the arch foot of the tunnel; the two ends of the left support section and the right support section and the upper end of the bottom support section are provided with end plates; the left support section and the right support section, as well as the left support section and the right support section and the corresponding bottom support section are connected as a whole through a guard plate. The present invention can convert the continuous radial extrusion pressure generated by the deformation of the surrounding rock into annular extrusion pressure, and then absorb the impact force generated by the deformation of the surrounding rock through its own annular retraction function, so as to avoid the impact of the deformation of the surrounding rock on the tunnel, which causes the steel arch frame to be twisted and broken, and has a good support effect, and can significantly improve the stability and safety of the tunnel structure.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel support, and in particular relates to a pressure-yielding energy-absorbing steel arch frame suitable for tunnels with large surrounding rock deformation. Background Art

[0002] With the rapid development of my country's economy, tunnel projects such as transportation, energy, water conservancy and hydropower are gradually spreading to deep and high-stress areas, and the scale of high-stress tunnel construction is increasing. Practice has shown that the large deformation disaster of surrounding rock during the construction of high-stress tunnels is more prominent, which is characterized by weak surrounding rock, large surrounding rock deformation, high deformation rate, and long deformation convergence time or even no convergence.

[0003] When large deformation of soft rock occurs in the tunnel, the surrounding rock continues to squeeze the support system. Conventional support structures are often limited by their mechanical properties, and the support effect is poor. Problems such as twisting and breaking of steel arch frames often occur, resulting in serious damage to the support, affecting the safety of the tunnel and increasing construction investment costs.

[0004] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art. Summary of the invention

[0005] The purpose of the present invention is to overcome the problem that the supporting effect of the traditional tunnel supporting system is poor, and the continuous squeezing of the surrounding rock when the soft rock is greatly deformed easily causes the steel arch frame to be twisted and misaligned.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A pressure-absorbing steel arch frame suitable for a tunnel with large deformation of surrounding rock, comprising: a top support section and an energy-absorbing assembly, wherein the top support section corresponds to the arch crown and arch waist of the tunnel, and the top support section is divided into a left support section and a right support section, and the lower ends of the left support section and the right support section are each provided with a bottom support section, and the bottom support section corresponds to the arch foot of the tunnel; both ends of the left support section and the right support section and the upper end of the bottom support section are each provided with an end plate; the left support section and the right support section, as well as the left support section and the right support section and the corresponding bottom support section are all connected as a whole through a guard plate, and the guard plate enables two adjacent support sections to be connected as a whole. A contraction space is formed between the end plates, so that the steel arch frame squeezed by the surrounding rock can shrink and deform along a ring shape; the energy absorbing component is arranged in the contraction space, and the energy absorbing component includes: a corrugated tube and an energy absorbing column, one end of the corrugated tube is butted with one of the end plates in the contraction space, the head end of the energy absorbing column is interference fit inside the other end of the corrugated tube, and the tail end of the energy absorbing column is butted with the other end plate in the contraction space; when the steel arch frame shrinks and deforms along a ring shape, the head end of the energy absorbing column gradually penetrates into the cylinder cavity along the corrugated wall of the corrugated tube.

[0008] In the pressure-yielding energy-absorbing steel arch frame applicable to tunnels with large surrounding rock deformation as described above, preferably, the left support segment, the right support segment and the bottom support segment are all I-beams.

[0009] Preferably, both ends of the guard plate are fixed to the corresponding wing plates of the left support section, the right support section or the bottom support section by bolts.

[0010] Preferably, the surface of the guard plate is provided with a guide groove along its length direction;

[0011] The width of the guide channel matches the diameter of the rod of the bolt so that the bolt at one end of the guard plate can slide in the guide channel.

[0012] Preferably, the energy absorbing column comprises: a column head, a column tube and a punch column, the column head is conical, and the front end diameter of the column head is smaller than the rear end diameter;

[0013] The rear end diameter of the column head matches the wave crest diameter of the cylinder cavity of the corrugated cylinder.

[0014] Preferably, the front end of the column barrel is butted against the rear end of the column cap.

[0015] Preferably, the length of the column tube plus the column head is not less than the length of the cylinder cavity of the corrugated cylinder.

[0016] Preferably, a slideway is provided on the surface of the column along the axial direction, and the rear end of the slideway is opened to be flush with the rear end of the column;

[0017] The front end of the punch column extends into the cavity of the column tube, and the rear end of the punch column is connected to the corresponding end plate;

[0018] The length of the punch column matches the length of the barrel cavity of the barrel.

[0019] Preferably, a limit plate protrudes radially from the surface of the punch column;

[0020] The width of the limiting plate matches the width of the slideway.

[0021] Preferably, the slideway and the limit plate are both distributed in plurality along the circumferential direction of the column;

[0022] The number of the limiting plates is greater than the number of the slideways, so that some of the limiting plates correspond to the slideways, and the remaining limiting plates are fixed to the rear end of the column.

[0023] Beneficial effects: The present invention can convert the continuous radial extrusion pressure generated by the deformation of the surrounding rock into annular extrusion pressure, and then absorb the impact force generated by the deformation of the surrounding rock through its own annular retraction function, so as to avoid the impact of the deformation of the surrounding rock on the tunnel causing the steel arch frame to twist and break. The support effect is good and can significantly improve the stability and safety of the tunnel structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0025] Figure 1 It is a front view schematic diagram of the present invention;

[0026] Figure 2 for Figure 1 The enlarged schematic diagram at A in the middle;

[0027] Figure 3 for Figure 1 A side view schematic diagram of

[0028] Figure 4 It is a schematic diagram of the overall structure of the present invention;

[0029] Figure 5 It is an overall schematic diagram of the energy absorbing component structure of the present invention.

[0030] In the figure: 1, left support section; 2, right support section; 3, bottom support section; 4, end plate; 5, guard plate; 501, guide channel; 6, corrugated tube; 7, column head; 8, column tube; 9, punch column; 10, slideway; 11, limit plate. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0032] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, they can be fixed connections or detachable connections; they can be directly connected or indirectly connected through intermediate components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0033] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0034] Embodiment: This embodiment aims to provide a pressure-absorbing and energy-absorbing steel arch frame suitable for tunnels with large deformation of surrounding rocks. Its main function is to effectively absorb the impact caused by the deformation of the surrounding rocks, avoid the distortion and dislocation of the steel arch frame, and significantly improve the stability of the tunnel structure.

[0035] Reference Figure 1 and Figure 4 , including: a top support section and an energy absorbing component, the top support section corresponds to the arch crown and arch waist of the tunnel, the top support section is divided into a left support section 1 and a right support section 2, and the lower ends of the left support section 1 and the right support section 2 are connected with a bottom support section 3, and the bottom support section 3 corresponds to the arch foot of the tunnel; end plates 4 are welded to the two ends of the left support section 1 and the right support section 2 and the upper end of the bottom support section 3, wherein the left support section 1, the right support section 2 and the bottom support section 3 are all made of I-beams.

[0036] Reference Figure 1 , Figure 3 and Figure 4The left support section 1 and the right support section 2, as well as the left support section 1 and the right support section 2 and the corresponding bottom support section 3 are connected as a whole through the guard plate 5, and a shrinkage space is formed between the two adjacent end plates 4 through the guard plate 5. Specifically, both ends of the guard plate 5 are fixed to the corresponding wing plates of the left support section 1, the right support section 2 or the bottom support section by bolts, and the surface of the guard plate 5 is provided with a guide groove 501 along its length direction, and the width of the guide groove 501 matches the rod diameter of the bolt, so that the rod of the bolt at one end of the guard plate 5 slides in the guide groove 501, thereby enabling the steel arch frame squeezed by the surrounding rock to shrink and deform along the ring. It should be understood that the guide groove 501 only provides a sliding track for the bolt at one end of the guard plate 5. Since both ends of the guard plate 5 are fastened by bolts, when the steel arch frame shrinks and deforms along the ring, sliding friction resistance will be generated between the guard plate 5 and the corresponding wing plate and the bolt head, and this resistance can absorb part of the impact force generated in the initial stage of surrounding rock deformation.

[0037] Reference Figure 1 and Figure 2 The energy absorbing component is arranged in the contraction space formed between two adjacent end plates 4. The energy absorbing component includes: a corrugated cylinder 6 and an energy absorbing column. The corrugated cylinder 6 is made of steel. One end of the corrugated cylinder 6 is welded and connected to one of the end plates 4 in the contraction space. The head end of the energy absorbing column is interference fit inside the other end of the corrugated cylinder 6. The tail end of the energy absorbing column is welded and connected to the other end plate 4 in the contraction space. When the steel arch frame contracts and deforms along the ring shape, the head end of the energy absorbing column gradually penetrates into the cylinder cavity along the corrugated wall of the corrugated cylinder 6. During this period, the corrugated wall of the corrugated cylinder 6 can generate an approximately constant resistance to the head end of the energy absorbing column. Through this resistance, the steel arch frame as a whole obtains an approximately constant support resistance, thereby exerting the pressure-releasing and energy-absorbing functions.

[0038] Reference Figure 1 , Figure 2 and Figure 5The energy absorbing column comprises: a column head 7, a column barrel 8 and a punch column 9. The column head 7 is conical, and the front end diameter of the column head 7 is smaller than the rear end diameter, so that the column head 7 can quickly enter the cylinder cavity of the corrugated cylinder 6. The rear end diameter of the column head 7 matches the cylinder cavity wave crest diameter of the corrugated cylinder 6, so that the cylinder wall of the corrugated cylinder 6 generates resistance to the rear end of the column head 7 to achieve the effect of energy absorption. The front end of the column barrel 8 is welded to the rear end of the column head 7; the surface of the column barrel 8 is provided with a slideway 10 along the axial direction, and the rear end of the slideway 10 is opened to be flush with the cylinder barrel 8. At the rear end, the front end of the punch column 9 extends into the cavity of the column tube 8, and the rear end of the punch column 9 is welded and docked with the corresponding end plate 4. The surface of the punch column 9 protrudes radially with a limit plate 11, and the width of the limit plate 11 matches the width of the slide 10; there are multiple slides 10 and limit plates 11 distributed along the circumferential direction of the column tube 8, among which four slides 10 are provided and eight limit plates 11 are provided, so that four of the limit plates 11 correspond to the four slides 10, and the remaining four limit plates 11 are welded to the rear end of the column tube 8.

[0039] In this embodiment, the length of the column tube 8 plus the column head 7 is not less than the length of the cylinder cavity of the corrugated tube 6, and can also be the same. The length of the punch column 9 is consistent with the length of the cylinder cavity of the column tube 8.

[0040] When the steel arch frame is squeezed and contracted along the ring shape by the deformation of the surrounding rock, first, the column head 7 of the energy absorbing column will gradually penetrate into the interior of the corrugated tube 6. During this period, each section of the concave corrugated wall on the corrugated tube 6 will interact with the column head 7, so as to achieve an effect of approximately constant energy absorption, until the column head 7 moves to the head of the corrugated tube 6. At this time, the column head 7 and the column tube 8 are just in the cylinder cavity of the corrugated tube 6, and the subsequent squeezing force of the surrounding rock deformation is resisted by the energy absorbing column. At this point, the steel arch frame changes from the initial pressure-yielding to the pressure-resistant, that is, the four limit plates 11 welded to the rear end of the column tube 8 in each energy absorbing column temporarily withstand the confining pressure. If the confining pressure still has a strong impact, the limit plate 11 welded to the rear end of the column tube 8 will be at risk of being broken. If the limit plate 11 welded to the rear end of the column tube 8 is broken, the front end of the punching column 9 will continue to It goes deeper into the cylinder cavity of the column tube 8. At the same time, the remaining limit plates 11 that are not welded to the rear end of the column tube 8 will move along the slide 10. The slide 10 provides a movable guiding space for the corresponding limit plates 11. Here, before the front end of the punch column 9 reaches the end of the cylinder cavity of the column tube 8, the limit plates 11 corresponding to the slide 10 will squeeze the corrugated tube 6 in advance. This process is called yielding. When the front end of the punch column 9 reaches the end of the cylinder cavity of the column tube 8, it becomes compression-resistant again, which is also the final support form of this steel arch frame. Based on this, after being squeezed by the surrounding rock deformation, this steel arch frame will experience an energy absorption process of yielding first, then resisting, then yielding, and then resisting again during the annular contraction period, which can provide super high support capacity for the tunnel, thereby effectively controlling the deformation of the surrounding rock, while also reducing the damage rate of the support structure, ensuring the construction progress and the safety of personnel and equipment.

[0041] The steel arch frame provided in this embodiment can convert the continuous radial extrusion pressure caused by the deformation of the surrounding rock into annular extrusion pressure, and then absorb the impact force caused by the deformation of the surrounding rock through its own annular retraction function, so as to avoid the impact of the deformation of the surrounding rock on the tunnel causing the steel arch frame to twist and break. The support effect is good and the stability and safety of the tunnel structure are significantly improved.

[0042] It should be understood that the above description is merely exemplary and the embodiments of the present application do not limit this.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A pressure-absorbing steel arch frame suitable for tunnels with large surrounding rock deformation, characterized in that: include: A top support section, corresponding to the arch crown and arch waist of the tunnel, the top support section is divided into a left support section and a right support section, the lower ends of the left support section and the right support section are both provided with a bottom support section, the bottom support section corresponds to the arch foot of the tunnel; End plates are provided at both ends of the left support section and the right support section and at the upper end of the bottom support section; The left support section and the right support section, as well as the left support section and the right support section and the corresponding bottom support section are connected as one body through a guard plate, and a shrinkage space is formed between two adjacent end plates through the guard plate, so that the steel arch frame squeezed by the surrounding rock shrinks and deforms along a ring shape; An energy absorbing component is arranged in the contraction space, and the energy absorbing component includes: a corrugated cylinder and an energy absorbing column, one end of the corrugated cylinder is butted with one of the end plates in the contraction space, the head end of the energy absorbing column is interference-fitted inside the other end of the corrugated cylinder, and the tail end of the energy absorbing column is butted with the other end plate in the contraction space; When the steel arch frame shrinks and deforms along the ring shape, the head end of the energy-absorbing column gradually penetrates into the cylinder cavity along the corrugated wall surface of the corrugated cylinder; The energy absorbing column comprises: a column head, a column tube and a punch column, the column head is conical, and the front end diameter of the column head is smaller than the rear end diameter; The rear end diameter of the column head matches the peak diameter of the corrugated cylinder; The front end of the column is butted against the rear end of the column head; The length of the column tube plus the column head is not less than the length of the cylinder cavity of the corrugated cylinder; A slideway is provided on the surface of the column along the axial direction, and the rear end of the slideway is opened to be flush with the rear end of the column; The front end of the punch column extends into the cavity of the column tube, and the rear end of the punch column is connected to the corresponding end plate; The length of the punch column matches the length of the barrel cavity of the barrel; A limit plate protrudes radially from the surface of the punch column; The width of the limit plate matches the width of the slideway; The slideway and the limit plate are both distributed in a plurality along the circumferential direction of the column; The number of the limiting plates is greater than the number of the slideways, so that some of the limiting plates correspond to the slideways, and the remaining limiting plates are fixed to the rear end of the column.

2. The pressure-relieving and energy-absorbing steel arch frame suitable for tunnels with large surrounding rock deformation according to claim 1 is characterized in that: The left support section, the right support section and the bottom support section are all I-beams.

3. The pressure-relieving and energy-absorbing steel arch frame suitable for tunnels with large surrounding rock deformation according to claim 2 is characterized in that: Both ends of the guard plate are fixed to the corresponding wing plates of the left support section, the right support section or the bottom support section by bolts.

4. The pressure-relieving and energy-absorbing steel arch frame suitable for tunnels with large surrounding rock deformation according to claim 3 is characterized in that: The surface of the guard plate is provided with a guide groove along its length direction; The width of the guide channel matches the diameter of the rod of the bolt so that the bolt at one end of the guard plate can slide in the guide channel.

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