Steel arch supporting assembly, steel arch supporting system and supporting control method of steel arch supporting system

Abstract

The steel arch supporting assembly comprises an inner support and an outer support, the outer support is of a split structure which is annularly divided into multiple sections of sub-frame bodies, and arc-shaped I-shaped steel is arranged between the adjacent sub-frame bodies; annular yielding assemblies used for controlling the distance between the end portions of the adjacent branch frame bodies are arranged between the adjacent end portions of the adjacent branch frame bodies and the arc-shaped I-shaped steel, and radial yielding assemblies used for controlling the radius of the outer support are arranged between the inner support and the arc-shaped I-shaped steel. The invention further provides a steel arch supporting system and a supporting control method thereof. According to the steel arch supporting assembly, the steel arch supporting system and the supporting control method, corresponding supporting force can be provided according to the change of surrounding rock stress, and local and overall yielding amounts are accurately controlled.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel construction, and in particular relates to a steel arch support assembly and a support control method thereof. Background Art

[0002] During tunnel excavation, the surrounding rock pressure pattern of the tunnel cross section will be affected differently due to the difference in cross-sectional shape. For road and railway tunnel projects, the circular design is an extremely stable building structure form, which can effectively withstand the huge pressure of the surrounding rock, ensure the stability of the tunnel and prevent collapse accidents.

[0003] The yielding support technology of circular steel arch support components has shown its effectiveness in dealing with the challenges of soft surrounding rock in high geostress environments. However, due to the rheological properties of soft surrounding rock, this property becomes particularly significant under the influence of high geostress. Specifically, even if the stress on the surrounding rock remains unchanged, its deformation will gradually increase over time. Cases of damage to steel arch support components due to excessive deformation are not uncommon. The current design of steel arch support components cannot provide corresponding support force according to the changes in surrounding rock stress, and it is difficult to accurately control the degree of local and overall yielding. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings and defects mentioned in the above background technology and provide a steel arch support assembly, a steel arch support system and a support control method for a circular cross-section tunnel. The steel arch support assembly and the support control method can provide corresponding support force according to the changes in surrounding rock stress and accurately control the local and overall yield.

[0005] In order to solve the above technical problems, the technical solution proposed by the present invention is: A steel arch support assembly for a circular tunnel comprises an inner support and an outer support, wherein the outer support is a split structure divided into a plurality of sub-frames in an annular direction, arc-shaped I-beams are arranged between adjacent sub-frames, an annular yielding assembly for controlling the distance between adjacent sub-frame ends is arranged between adjacent ends of adjacent sub-frames and the arc-shaped I-beams, and a radial yielding assembly for controlling the radius of the outer support is arranged between the inner support and the arc-shaped I-beams.

[0006] The arc-shaped I-beam includes an arc-shaped outer top surface (located on the outside of the steel arch support assembly) and an arc-shaped inner bottom surface (located on the inside of the steel arch support assembly), a vertical connecting plate is provided between the arc-shaped outer top surface and the arc-shaped inner bottom surface, the annular pressure-relieving assembly is provided between the end of the sub-frame and the vertical connecting plate, and the radial pressure-relieving assembly is provided between the inner support and the arc-shaped inner bottom surface. The arc-shaped I-beam and the circular cross-section steel arch support assembly have better matching properties. Specifically, from a mechanical point of view, after the arc-shaped I-beam is connected to the sub-frame, it can effectively transmit force and bear load. The arc-shaped I-beam can provide bending and compression resistance that are compatible with the sub-frame, and can work together with the sub-frame to resist external forces such as surrounding rock pressure to maintain structural stability. In terms of structural matching, the arc-shaped I-beam and the arc-shaped sub-frame are in harmony with each other, which is convenient for connection and forming an integral structure. The connection nodes can be reasonably designed to enable the two to work well together after being connected.

[0007] The annular pressure relief assembly includes an arc-shaped hydraulic cylinder, a guide rail and a slider. The guide rail is arranged on the vertical connecting plate and is arranged parallel to the vertical connecting plate (that is, the setting direction of the guide rail points to the center of the steel arch support assembly). The slider can be slidably arranged on the guide rail. One end of the arc-shaped hydraulic cylinder is arranged at the end of the sub-frame body, and the other end is arranged on the slider. The guide rail provides precise guidance for the slider, so that the slider can slide up and down along the guide rail. In combination with the expansion and contraction of the arc-shaped hydraulic cylinder, the distance between the ends of adjacent sub-frame bodies can be controlled to change the radius of the outer support. Specifically, when it is necessary to reduce the radius of the outer support, the slider slides on the guide rail toward the center of the steel arch support assembly, and the arc-shaped hydraulic cylinder shrinks at the same time, reducing the distance between the end of the sub-frame body and the vertical connecting plate, which is equivalent to reducing the circumference of the outer support, so that the radius of the outer support can be reduced. Conversely, when it is necessary to increase the radius of the outer support, it is only necessary to make the sliding direction of the slider away from the center of the steel arch support assembly and extend the arc-shaped hydraulic cylinder outward.

[0008] The radial yielding assembly is a vertical hydraulic cylinder, which is arranged between the outer ring surface of the inner support and the arc-shaped inner bottom surface. The vertical hydraulic cylinder is used to adjust the radius of the outer support and can cooperate with the annular yielding assembly to play a role. When the vertical hydraulic cylinder contracts, it can drive the arc-shaped I-beam to shrink inward, thereby reducing the radius of the outer support. When the vertical hydraulic cylinder extends outward, it can drive the arc-shaped I-beam to extend outward, thereby increasing the radius of the outer support.

[0009] In the above-mentioned steel arch support assembly, preferably, a buffer elastic body is provided between the sub-frame and the arc-shaped inner bottom surface, and the lower surface of the buffer elastic body can be slidably provided on the arc-shaped inner bottom surface. The provision of the buffer elastic body can better transfer the stress on the sub-frame to the arc-shaped I-beam, further reduce the shear stress on the arc-shaped hydraulic cylinder, and facilitate the coordinated force of the outer support as a whole. The buffer elastic body has a certain elasticity and can be compressed and self-reset.

[0010] The present invention utilizes the cooperation of the vertical hydraulic cylinder and the arc hydraulic cylinder to adjust the radius of the outer support within a larger range. If only the arc hydraulic cylinder is used, the radius adjustment range of the outer support is small due to the limited length of the vertical connecting plate and the guide rail and the limited sliding distance of the slider. Figure 2 For example, when the slider slides to the bottom of the guide rail, the radius of the outer support cannot be adjusted. If the slider slides to the bottom of the guide rail, and then adjusts the vertical hydraulic cylinder to drive the arc I-beam to slide downward, the position of the vertical connecting plate can be adjusted, thereby changing the relative position of the guide rail and the slider, so that the slider is located above the guide rail, and the radius of the outer support can be further adjusted.

[0011] In the present invention, after the steel arch support assembly is erected, its side surface is closed by elastic concrete or partitions.

[0012] In the present invention, the contraction stroke of the vertical hydraulic cylinder and the arc hydraulic cylinder is limited, and specifically may include: a hydraulic cylinder, a piston rod, a valve, an oil tank, a hydraulic pump, a control valve, etc. The hydraulic pump converts the kinetic energy of the motor into the pressure energy of the hydraulic oil, so that the hydraulic oil generates high pressure, and the hydraulic oil enters the suction port of the hydraulic pump. Under the push of the pump, the hydraulic oil is transported to the hydraulic cylinder. The piston rod in the hydraulic cylinder generates pressure to the other side under the pressure of the hydraulic oil, thereby pushing the piston rod to move. In the working process of the hydraulic cylinder, the pressure and flow of the hydraulic oil are two important parameters. The pressure of the hydraulic oil determines the output force of the hydraulic cylinder, and the flow of the hydraulic oil determines the movement speed of the hydraulic cylinder. By adjusting the pressure and flow in the vertical hydraulic cylinder and the arc hydraulic cylinder, the vertical hydraulic cylinder and the arc hydraulic cylinder can be precisely controlled, so that the vertical pressure of the steel arch support assembly can be precisely controlled. For example, when it is necessary to increase the supporting force of the vertical hydraulic cylinder or the arc hydraulic cylinder, the pressure of the hydraulic oil can be increased.

[0013] In the above steel arch support assembly, preferably, the outer support is evenly divided into multiple sections in the circumferential direction, and the inner support is an integral steel ring. The outer support is evenly divided in the circumferential direction and connected by arc-shaped I-beams, and then a vertical hydraulic cylinder is arranged outside the integral steel ring to form a compression support steel arch support assembly.

[0014] As a general technical concept, the present invention also provides a steel arch support system, including the above-mentioned steel arch support assembly, wherein the arc-shaped I-beam is provided with a stress monitoring assembly for monitoring the stress change of the surrounding rock. The stress monitoring assembly can be used to monitor the change of the surrounding rock stress, so as to facilitate the targeted adjustment of the steel arch support assembly to match the stress change of the surrounding rock.

[0015] In the above-mentioned steel arch support system, preferably, the stress monitoring component includes a memory alloy layer arranged on the outside of the arc-shaped outer top surface and a current monitor connected to the memory alloy layer. The sub-frames of the external support are connected through arc-shaped I-beams, the outer radius of the arc-shaped I-beams is larger than the outer radius of the sub-frames, and the arc-shaped outer top surface of the arc-shaped I-beams is closer to the surrounding rock, which will first sense the changes in the surrounding rock stress. The memory alloy layer is arranged on the outside of the arc-shaped outer top surface, which can improve the accuracy of sensing the changes in the surrounding rock stress, so as to accurately and quickly implement the yielding support strategy of the steel arch support component.

[0016] The present invention also includes a control system (which is the prior art). The arc hydraulic cylinder of the annular pressure-releasing assembly and the vertical hydraulic cylinder of the radial pressure-releasing assembly are both connected to the control system. The control system is connected to the stress monitoring assembly. By receiving information provided by the stress monitoring assembly, the actions of the arc hydraulic cylinder and the vertical hydraulic cylinder are controlled so that their actions match each other.

[0017] As a general technical concept, the present invention also provides a support control method for the above-mentioned steel arch support system, comprising the following steps: S1: When the stress monitoring component detects that the surrounding rock stress of a part of the section of the steel arch support component increases but does not increase to the ultimate bearing capacity of the steel arch support component of the section, the supporting force provided by the annular yielding component and the radial yielding component of the section is increased to cope with the increase in surrounding rock stress; S2: When the stress monitoring component detects that the surrounding rock stress of a part of the section of the steel arch support component increases to the ultimate bearing capacity of the steel arch support component of the section, the distance between the adjacent ends of the sub-frames of the section is reduced by the annular pressure-yielding component, so that the sub-frames of the section are retracted inward, and at the same time, the outer support of the section is retracted as a whole by the radial pressure-yielding component, so as to provide an escape space for the surrounding rock to release energy by plastic deformation; S3: As the surrounding rock stress decreases, when the stress monitoring component detects that the surrounding rock stress of a partial section of the steel arch support assembly is less than the ultimate bearing capacity of the steel arch support assembly of the section, the annular yielding assembly and the radial yielding assembly of the section stop moving.

[0018] More specifically, when the surrounding rock stress of the steel arch support assembly in a certain section increases to the ultimate bearing capacity of the steel arch support assembly in this section, the thrust of the hydraulic oil in the arc hydraulic cylinder on the piston rod can be reduced, and the flow of the hydraulic oil can be controlled so that the arc hydraulic cylinder in this section slowly retracts in a circular direction. At the same time, the slider moves toward the center of the steel arch support assembly, which can retract this part of the outer support. The vertical hydraulic cylinder can also be retracted synchronously to further reduce the radius of the outer support and provide more avoidance space. During the retraction process, the surrounding rock undergoes plastic deformation, so that part of the energy in the surrounding rock is released. After the surrounding rock stress is weakened, the thrust of the hydraulic oil in the arc hydraulic cylinder or the vertical hydraulic cylinder on the piston rod is increased, so that the arc hydraulic cylinder or the vertical hydraulic cylinder stops retracting. At the same time, the slider stops moving, so that this part of the outer support stops retracting, and the supporting force of the steel arch support assembly on the surrounding rock in this section is restored.

[0019] As a general technical concept, the present invention also provides a support control method for the above-mentioned steel arch support system, comprising the following steps: S1: When the stress monitoring component detects that the surrounding rock stress in all sections of the steel arch support component increases but does not increase to the ultimate bearing capacity of the steel arch support component, the supporting force provided by the annular yielding component and the radial yielding component is increased to cope with the increase in surrounding rock stress; S2: When the stress monitoring component detects that the surrounding rock stress on all sections of the steel arch support component increases to the ultimate bearing capacity of the steel arch support component, the distance between the adjacent ends of the sub-frames is reduced by the annular pressure-yielding component to shrink the sub-frames, and the outer support is retracted as a whole by the radial pressure-yielding component to provide a space for the surrounding rock to release energy by plastic deformation; S3: As the surrounding rock stress decreases, when the stress monitoring component detects that the surrounding rock stress on all sections of the steel arch support component is less than the ultimate bearing capacity of the steel arch support component, the annular yielding component and the radial yielding component stop moving.

[0020] More specifically, when the surrounding rock stress of all steel arch support assemblies increases to the ultimate bearing capacity of the steel arch support assemblies, the thrust of the hydraulic oil on the piston rod in all vertical hydraulic cylinders can be reduced, and the flow of the hydraulic oil can be controlled, so that all vertical hydraulic cylinders slowly retract in the direction of movement toward the center of the steel arch support assembly. At the same time, the thrust of the hydraulic oil on the piston rod in all arc hydraulic cylinders can be reduced, and the flow of the hydraulic oil can be controlled, so that all arc hydraulic cylinders slowly retract in the direction of movement in a circumferential direction. At the same time, the slider moves toward the center of the steel arch support assembly, so that all external supports can retract. During the retraction process, the surrounding rock undergoes plastic deformation, so that part of the energy in the surrounding rock is released. After the surrounding rock stress is weakened, the thrust of the hydraulic oil on the piston rod in the arc hydraulic cylinder or the vertical hydraulic cylinder is increased, so that the arc hydraulic cylinder or the vertical hydraulic cylinder stops retracting. At the same time, the slider stops moving, so that all external supports stop retracting, and the supporting force of the steel arch support assembly on the surrounding rock is restored.

[0021] In the above support control method, preferably, when the annular pressure-yielding assembly and the radial pressure-yielding assembly reach the limit of inward contraction, the inner support and the outer support are almost combined into one steel arch support assembly, and can bear force together.

[0022] The present invention can control and adjust the supporting force of the steel arch support assembly through the annular pressure-yielding assembly and the radial pressure-yielding assembly, and is suitable for the steel arch support assembly of a circular cross-section tunnel. It has the functions of exerting the self-bearing capacity of the surrounding rock, reasonably releasing the surrounding rock stress, and reasonably controlling the deformation of the surrounding rock, and can improve the bearing capacity of the circular steel arch support assembly. During the deformation of the tunnel surrounding rock, the pressure and flow of the hydraulic oil can be controlled to accurately control the movement direction and movement size of the piston rod in the vertical hydraulic cylinder and the arc hydraulic cylinder. In conjunction with the guide rail and the slider, the pressure-yielding value of the steel arch support assembly can be accurately controlled, and the support mode of support-strong support-pressure-yielding support-support can be realized, so as to achieve the effect of the steel arch support assembly on multi-stage treatment of the surrounding rock stress.

[0023] Specifically, the first support stage is that after the initial installation of the steel arch support assembly, it has a corresponding support force on the surrounding rock, and at this time the steel arch support assembly is far from reaching the ultimate bearing capacity. The second strong support stage is that after the initial installation of the steel arch support assembly, with the development of time, the surrounding rock stress changes. Although it has not reached the ultimate bearing capacity of some steel arch support assemblies or the entire steel arch support assembly, it is necessary to increase the strength and stiffness of some steel arch support assemblies or the entire steel arch support assembly, increase the hydraulic oil pressure of the vertical hydraulic cylinder and the arc hydraulic cylinder in the radial yielding assembly and the annular yielding assembly, so that the vertical hydraulic cylinder and the arc hydraulic cylinder The supporting force of the steel arch support assembly is increased, thereby strengthening the strength and stiffness of the steel arch support assembly. The third yield support stage is that as time goes by, the surrounding rock stress becomes greater and greater, and when the partial steel arch support assembly or the entire steel arch support assembly gradually reaches the ultimate bearing capacity, the pressure of the hydraulic oil in the vertical hydraulic cylinder and the arc hydraulic cylinder is reduced, and the flow of the hydraulic oil is controlled. At the same time, the slider moves toward the center of the steel arch support assembly, so that the partial steel arch support assembly or the entire steel arch support assembly slowly begins to retract. During the retraction process, the surrounding rock undergoes plastic deformation, so that part of the energy in the surrounding rock is released. The fourth support stage is that when the partial steel arch support assembly or the entire steel arch support assembly retracts a certain value, the surrounding rock energy is weakened, and the pressure of the hydraulic oil in the vertical hydraulic cylinder and the arc hydraulic cylinder is restored. At the same time, the slider stops sliding, so that the partial steel arch support assembly or the entire steel arch support assembly stops retracting. At this time, the steel arch support assembly returns to the first stage.

[0024] The above-mentioned process of support - strong support - pressure-relieving support - support can be cyclically performed in the support process of the steel arch support assembly, so that the steel arch support assembly can reasonably analyze the state of the surrounding rock, reasonably support it, and reasonably yield pressure.

[0025] Compared with the prior art, the advantages of the present invention are: The steel arch support assembly, steel arch support system and support control method thereof for circular cross-section tunnels of the present invention can control and adjust the supporting force of the steel arch support assembly by means of annular yielding assemblies and radial yielding assemblies, can provide corresponding supporting force according to changes in surrounding rock stress, accurately control local and overall yielding amounts, achieve the effect of multi-stage treatment of surrounding rock stress by the steel arch support assembly, and can improve the bearing capacity of the circular cross-section steel arch support assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 Schematic diagram of the structure of the steel arch support assembly in the embodiment.

[0028] Figure 2 It is a schematic structural diagram of the first annular pressure relief assembly in the embodiment.

[0029] Figure 3 Schematic diagram of the structure of the second annular pressure relief assembly in the embodiment.

[0030] Figure 4 Schematic diagram of the structure of the radial pressure relief assembly in the embodiment.

[0031] Figure 5 Schematic diagram of the structure of the steel arch support system in the embodiment.

[0032] Legend 1. Inner support; 2. Outer support; 21. Sub-frame; 3. Annular pressure-relieving assembly; 31. Arc-shaped hydraulic cylinder; 32. Guide rail; 33. Slider; 4. Radial pressure-relieving assembly; 5. Arc-shaped I-beam; 51. Arc-shaped outer top surface; 52. Arc-shaped inner bottom surface; 53. Vertical connecting plate; 6. Buffering elastomer; 7. Stress monitoring assembly; 71. Memory alloy layer; 72. Current monitor. DETAILED DESCRIPTION

[0033] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and meticulously below in conjunction with the accompanying drawings and preferred embodiments of the present invention, but the protection scope of the present invention is not limited to the following specific embodiments.

[0034] It should be noted that when an element is described as being "fixed, fixed, connected or connected to" another element, it can be directly fixed, fixed, connected or connected to the other element, or it can be indirectly fixed, fixed, connected or connected to the other element through other intermediate connectors.

[0035] Unless otherwise defined, all the professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0036] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0037] Example: like Figure 1As shown, the steel arch support assembly for a circular cross-section tunnel of this embodiment includes an inner support 1 and an outer support 2, wherein the inner support 1 is an integral steel ring, and the outer support 2 is a split structure evenly divided into eight sub-frames 21 in a circumferential direction, and an arc-shaped I-beam 5 is provided between adjacent sub-frames 21, and an annular yielding assembly 3 for controlling the distance between the ends of adjacent sub-frames 21 is provided between adjacent ends of adjacent sub-frames 21 and the arc-shaped I-beam 5, and a radial yielding assembly 4 for controlling the radius of the outer support 2 is provided between the inner support 1 and the arc-shaped I-beam 5.

[0038] In other embodiments, the outer support 2 may also be a split structure that is evenly divided into other numbers of sub-frames 21 in the circumferential direction.

[0039] like Figure 2 As shown, in this embodiment, the arc-shaped I-beam 5 includes an arc-shaped outer top surface 51 and an arc-shaped inner bottom surface 52, a vertical connecting plate 53 is provided between the arc-shaped outer top surface 51 and the arc-shaped inner bottom surface 52, the annular pressure-releasing assembly 3 is provided between the end of the sub-frame 21 and the vertical connecting plate 53, and the radial pressure-releasing assembly 4 is provided between the inner support 1 and the arc-shaped inner bottom surface 52.

[0040] In this embodiment, the annular pressure relief assembly 3 includes an arc-shaped hydraulic cylinder 31, a guide rail 32 and a slider 33. The guide rail 32 is arranged on the vertical connecting plate 53 and is arranged parallel to the vertical connecting plate 53. The slider 33 can be slidably arranged on the guide rail 32. One end of the arc-shaped hydraulic cylinder 31 is arranged at the end of the sub-frame 21, and the other end is arranged on the slider 33.

[0041] like Figure 3 As shown, in other embodiments, a buffer elastic body 6 is disposed between the sub-frame body 21 and the arc-shaped inner bottom surface 52 , and the lower surface of the buffer elastic body 6 can be slidably disposed on the arc-shaped inner bottom surface 52 .

[0042] like Figure 4 As shown, in this embodiment, the radial pressure relief assembly 4 is a vertical hydraulic cylinder, and the vertical hydraulic cylinder is arranged between the outer ring surface of the inner support 1 and the arc-shaped inner bottom surface 52.

[0043] like Figure 5 As shown, the steel arch support system of this embodiment includes the above-mentioned steel arch support assembly, and a stress monitoring assembly 7 for monitoring the stress change of the surrounding rock is provided on the arc-shaped I-beam 5. The stress monitoring assembly 7 includes a memory alloy layer 71 provided on the outer side of the arc-shaped outer top surface 51 and a current monitor 72 connected to the memory alloy layer 71.

[0044] The support control method of the steel arch support system of this embodiment, for some sections, includes the following steps: S1: When the stress monitoring component 7 detects that the surrounding rock stress of a part of the section of the steel arch support component increases, but does not increase to the ultimate bearing capacity of the steel arch support component of the section, the supporting force provided by the annular yielding component 3 and the radial yielding component 4 of the section is increased to cope with the increase of the surrounding rock stress; S2: When the stress monitoring component 7 detects that the surrounding rock stress of a part of the section of the steel arch support component increases to the ultimate bearing capacity of the steel arch support component of the section, the distance between the ends of the adjacent sub-frames 21 of the section is reduced by the annular pressure-yielding component 3, so that the sub-frames 21 of the section are retracted, and at the same time, the outer support 2 of the section is retracted as a whole by the radial pressure-yielding component 4, so as to provide an escape space for the surrounding rock to release energy by plastic deformation; S3: As the surrounding rock stress decreases, when the stress monitoring component 7 detects that the surrounding rock stress of a partial section of the steel arch support assembly is less than the ultimate bearing capacity of the steel arch support assembly in this section, the annular yielding assembly 3 and the radial yielding assembly 4 of this section stop moving.

[0045] The support control method of the steel arch support system of this embodiment, for all sections, includes the following steps: S1: When the stress monitoring component 7 detects that the surrounding rock stress in all sections of the steel arch support component increases but does not increase to the ultimate bearing capacity of the steel arch support component, the supporting force provided by the annular yielding component 3 and the radial yielding component 4 is increased to cope with the increase in surrounding rock stress; S2: When the stress monitoring component 7 detects that the surrounding rock stress of all sections of the steel arch support component increases to the ultimate bearing capacity of the steel arch support component, the distance between the ends of adjacent sub-frames 21 is reduced through the annular pressure-yielding component 3, so that the sub-frames 21 shrink inward, and at the same time, the outer support 2 shrinks inward as a whole through the radial pressure-yielding component 4, so as to provide a space for the surrounding rock to release energy by plastic deformation; S3: As the surrounding rock stress decreases, when the stress monitoring component 7 detects that the surrounding rock stress of all sections of the steel arch support component is less than the ultimate bearing capacity of the steel arch support component, the annular yielding component 3 and the radial yielding component 4 stop moving.

[0046] This embodiment can control and adjust the supporting force of the steel arch support assembly through the annular pressure-releasing assembly 3 and the radial pressure-releasing assembly 4, and is suitable for the steel arch support assembly of a circular cross-section tunnel. It has the functions of exerting the self-bearing capacity of the surrounding rock, reasonably releasing the surrounding rock stress, and reasonably controlling the deformation of the surrounding rock, and can improve the bearing capacity of the circular steel arch support assembly. During the deformation of the tunnel surrounding rock, the pressure and flow of the hydraulic oil can be controlled to accurately control the movement direction and movement size of the piston rod in the vertical hydraulic cylinder and the arc hydraulic cylinder 31. In conjunction with the guide rail 32 and the slider 33, the pressure-releasing value of the steel arch support assembly can be accurately controlled, and the support mode of support-strong support-pressure-releasing support-support can be realized, so as to achieve the effect of multi-stage treatment of the surrounding rock stress by the steel arch support assembly.

[0047] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A steel arch support assembly for a circular cross-section tunnel, characterized in that: It comprises an inner support (1) and an outer support (2), the outer support (2) being a split structure divided into a plurality of sub-frames (21) in an annular direction, an arc-shaped I-beam (5) being provided between adjacent sub-frames (21), an annular pressure-relief assembly (3) for controlling the distance between adjacent ends of the sub-frames (21) being provided between adjacent ends of the adjacent sub-frames (21) and the arc-shaped I-beam (5), and a radial pressure-relief assembly (4) for controlling the radius of the outer support (2) being provided between the inner support (1) and the arc-shaped I-beam (5); The arc-shaped I-beam (5) comprises an arc-shaped outer top surface (51) and an arc-shaped inner bottom surface (52), a vertical connecting plate (53) is provided between the arc-shaped outer top surface (51) and the arc-shaped inner bottom surface (52), the annular pressure-releasing assembly (3) is provided between the end of the sub-frame (21) and the vertical connecting plate (53), and the radial pressure-releasing assembly (4) is provided between the inner support (1) and the arc-shaped inner bottom surface (52); The annular pressure-releasing assembly (3) comprises an arc-shaped hydraulic cylinder (31), a guide rail (32) and a slide block (33); the guide rail (32) is arranged on the vertical connecting plate (53) and is arranged parallel to the vertical connecting plate (53); the slide block (33) is slidably arranged on the guide rail (32); one end of the arc-shaped hydraulic cylinder (31) is arranged on the end of the sub-frame (21), and the other end is arranged on the slide block (33); The radial pressure relief assembly (4) is a vertical hydraulic cylinder, and the vertical hydraulic cylinder is arranged between the outer ring surface of the inner support (1) and the arc-shaped inner bottom surface (52).

2. The steel arch support assembly according to claim 1, characterized in that: A buffer elastic body (6) is provided between the sub-frame body (21) and the arc-shaped inner bottom surface (52), and the buffer elastic body (6) is slidably provided on the arc-shaped inner bottom surface (52).

3. The steel arch support assembly according to claim 1, characterized in that: The outer support (2) is evenly divided into a plurality of sub-frames (21) in the circumferential direction, and the inner support (1) is an integral steel ring.

4. A steel arch support system, characterized in that: It comprises the steel arch support assembly according to any one of claims 1 to 3, wherein the arc-shaped I-beam (5) is provided with a stress monitoring assembly (7) for monitoring changes in surrounding rock stress.

5. The steel arch support system according to claim 4, characterized in that: The stress monitoring component (7) comprises a memory alloy layer (71) arranged outside the arc-shaped outer top surface (51) and a current monitor (72) connected to the memory alloy layer (71).

6. A support control method for a steel arch support system according to claim 4 or 5, characterized in that: The following steps are involved: S1: When the stress monitoring component (7) detects that the surrounding rock stress in a part of the section of the steel arch support component increases but does not increase to the ultimate bearing capacity of the steel arch support component in the section, the supporting force provided by the annular yielding component (3) and the radial yielding component (4) in the section is increased to cope with the increase in surrounding rock stress; S2: When the stress monitoring component (7) detects that the surrounding rock stress on a part of the section of the steel arch support component increases to the ultimate bearing capacity of the steel arch support component of the section, the distance between the ends of the adjacent sub-frames (21) of the section is reduced by the annular pressure-yielding component (3), so that the sub-frames (21) of the section are retracted, and at the same time, the outer support (2) of the section is retracted as a whole by the radial pressure-yielding component (4), so as to provide an escape space for the surrounding rock to release energy through plastic deformation; S3: As the surrounding rock stress decreases, when the stress monitoring component (7) detects that the surrounding rock stress on a partial section of the steel arch support component is less than the ultimate bearing capacity of the steel arch support component in this section, the annular pressure-yielding component (3) and the radial pressure-yielding component (4) in this section stop moving.

7. A support control method for a steel arch support system according to claim 4 or 5, characterized in that: The following steps are involved: S1: When the stress monitoring component (7) detects that the surrounding rock stress in all sections of the steel arch support component increases but does not increase to the ultimate bearing capacity of the steel arch support component, the supporting force provided by the annular yielding component (3) and the radial yielding component (4) is increased to cope with the increase in surrounding rock stress; S2: When the stress monitoring component (7) detects that the surrounding rock stress in all sections of the steel arch support component increases to the ultimate bearing capacity of the steel arch support component, the distance between the ends of the adjacent sub-frames (21) is reduced through the annular pressure-yielding component (3), so that the sub-frames (21) are retracted, and at the same time, the outer support (2) is retracted as a whole through the radial pressure-yielding component (4), so as to provide an escape space for the surrounding rock to release energy through plastic deformation; S3: As the surrounding rock stress decreases, when the stress monitoring component (7) detects that the surrounding rock stress on all sections of the steel arch support component is less than the ultimate bearing capacity of the steel arch support component, the annular yielding component (3) and the radial yielding component (4) stop moving.

Images