Anti-floor-heave tunnel inverted-arch support structure

Abstract

The application provides a tunnel inverted arch support form resisting floor heave, which can improve the floor heave resistance of the tunnel inverted arch, and reduce the upward floating and cracks of the inverted arch and the inverted arch filling. The tunnel inverted arch support form comprises an inverted arch filling and an inverted arch. The inverted arch filling comprises an umbrella-shaped support. The middle part of the umbrella-shaped support is connected with the inverted arch reinforcement through a nearly H-shaped steel frame. The upper part of the umbrella-shaped support is connected with a door-shaped steel frame. The middle part of the door-shaped steel frame is connected with the inverted arch reinforcement through an eight-shaped steel frame. The lower part of the door-shaped steel frame is connected with the H-shaped steel frame. The tunnel inverted arch support form further comprises anchor rods, which are connected with the umbrella-shaped support, the H-shaped steel frame and the eight-shaped steel frame through the inverted arch reinforcement. The tunnel inverted arch support form comprises at least one umbrella-shaped support, one H-shaped steel frame, one door-shaped steel frame, one eight-shaped steel frame and a plurality of anchor rods. Through the above combination, the floor heave resistance of the inverted arch structure can be effectively improved, and the floor heave damage of the inverted arch structure can be prevented.

Description

Technical Field

[0001] This invention mainly relates to the technical field of building construction, specifically to a tunnel arch support structure that is resistant to bottom heave. Background Technology

[0002] The problem of invert arch bulging is rampant, especially in tunnels with high ground stress. Often, due to insufficient support of the invert arch, the invert arch and its filling slowly bulge under the action of huge jacking force, which directly endangers the safety of train operation.

[0003] The cross-section of high-speed railway double-track tunnels is generally over 100 square meters, which to some extent limits the curvature of the invert arch. This results in the invert arch structure at the bottom of the tunnel not fully forming its arch effect. Under the lifting force of the surrounding rock at the tunnel bottom, the bottom bulging at the middle position of the invert arch is most obvious, and tensile cracks first appear in the concrete at the center of the invert arch filling surface. Therefore, a reasonable support structure needs to be designed to solve the problem of bottom bulging of the tunnel invert arch. Summary of the Invention

[0004] To address the shortcomings of current technologies, this invention, combining existing technologies and based on practical applications, provides a tunnel invert arch support structure that resists bottom heave.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: A tunnel invert support structure for preventing bottom heave includes an invert primary support, an invert secondary lining, and an invert filler. The invert filler is provided with an umbrella-shaped support, which is vertically arranged on a certain cross-section of the tunnel and connects the invert primary support, the invert secondary lining, and the invert filler.

[0006] Furthermore, the upper part of the umbrella-shaped support has multiple steel supports, which extend obliquely upwards during the filling of the invert arch. The multiple steel supports, like an open umbrella, disperse the lifting force on the center of the invert arch to the surrounding areas.

[0007] Furthermore, the upper part of the steel support is connected to the edge of the circular steel plate, and the circular steel plate connects multiple steel supports into a whole. The umbrella-shaped bracket, the steel support, and the circular steel plate together form a complete umbrella-shaped support structure.

[0008] Furthermore, the steel support consists of 6 pieces, and the circular steel plate is higher in the middle and lower around the edges.

[0009] Furthermore, the middle part of the umbrella-shaped support is hinged to the Z-shaped steel frame, and the hinge point is set in the middle of the Z-shaped steel frame, dividing the Z-shaped steel frame into two independent force-bearing parts symmetrical along the umbrella-shaped support. The corner of the Z-shaped steel frame itself is a rotatable hinge.

[0010] Furthermore, the bottom of the Z-shaped steel frame and the umbrella-shaped support are respectively connected to the corresponding anti-buoyancy anchor rods, and the connection point is rigidly connected by the inverted arch steel bars.

[0011] Further, a door-shaped steel frame is rigidly connected to the top of the umbrella-shaped support, a plurality of steel supports penetrate through the middle of the door-shaped steel frame, and the bottom ends of two sides of the door-shaped steel frame are rigidly connected to the middles of two sides of the inverted V-shaped steel frame respectively.

[0012] Further, the middles of two sides of the door-shaped steel frame are rigidly connected to the upper ends of two sides of the splayed steel frame respectively, and the lower ends of the splayed steel frame are connected with inverted arch reinforcements.

[0013] Further, the lower ends of the splayed steel frame are connected with hollow grouting anchor rods, and the splayed steel frame and the hollow grouting anchor rods are rigidly connected with the inverted arch reinforcements at the same time.

[0014] Beneficial effects of the present invention: 1. In the present invention, an umbrella-shaped support, a steel support and a circular steel plate are arranged at the center of an inverted arch to form a complete umbrella-shaped supporting structure. On one hand, the umbrella-shaped support is connected with an anti-floating anchor rod at the bottom, which increases the anti-bottom-heave capacity of the umbrella-shaped structure; on the other hand, the combination composed of the upper steel support and the circular steel plate can effectively share the jacking force at the bottom, disperse the originally concentrated jacking force to the surroundings, and reduce the jacking force at the center of the inverted arch.

[0015] 2. In the present invention, the inverted V-shaped steel frame, the door-shaped steel frame, the splayed steel frame and the inverted arch reinforcement form a four-layer anti-bottom-heave structure in the vertical direction of the tunnel cross section. Firstly, the corner points of the inverted V-shaped steel frame are designed to be hinged, the bottom is rigidly connected with the inverted arch reinforcement and the anti-floating anchor rod, and the upper part is hinged with the umbrella-shaped support. When the jacking force acts on the center of the inverted arch, the inverted V-shaped steel frame can firmly lock the door-shaped steel frame through the relative movement trend of the upper part and the lower part, forcing the door-shaped steel frame and the umbrella-shaped support to stop floating upward; secondly, the door-shaped steel frame is rigidly connected with the splayed steel frame, and the splayed steel frame is rigidly connected with the hollow grouting anchor rod, which further limits the bottom heave of the inverted arch structure.

[0016] 3. In the present invention, two hollow grouting anchor rods connected with the upper structure are arranged on the left and right sides, which can effectively reduce the bottom heave of the inverted arch arch foot; three anti-floating anchor rods are arranged in the middle, and the upper supporting structure is rigidly connected thereto, which increases the integrity of the supporting structure and can greatly improve the anti-bottom-heave capacity of the inverted arch structure. Description of Drawings

[0017] Fig. Figure 1 is a schematic diagram of a cross-sectional structure of an anti-bottom-heave inverted arch support form in the present invention; Fig. Figure 2 is a schematic diagram of an implemented structure of an anti-bottom-heave inverted arch support form in the present invention.

[0018] Reference numerals shown in the drawings: 100. Initial support for the invert arch; 101. Secondary lining for the invert arch; 102. Invert arch filling; 103. Umbrella-shaped support; 104. Steel support; 105. Circular steel plate; 106. Z-shaped steel frame; 107. Portal-shaped steel frame; 108-shaped steel frame; 109. Hollow grouting anchor; 110. Anti-buoyancy anchor. Detailed Implementation

[0019] The present invention will be further described in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined in this application.

[0020] like Figure 1 and Figure 2 As shown, this embodiment provides a type of anti-bottom heave tunnel invert arch support.

[0021] It mainly includes the initial support 100 of the invert arch, the secondary lining 101 of the invert arch, and the invert arch filling 102. The invert arch filling 102 is equipped with an umbrella-shaped support 103. The bottom of the umbrella-shaped support 103 is connected to the invert arch reinforcement and is also rigidly connected to the anti-buoyancy anchor rod 110, thereby firmly fixing the combined support structure in the invert arch filling to the deep surrounding rock.

[0022] Specifically, the upper part of the umbrella-shaped support 103 is connected to multiple (6) steel supports 104. The steel supports 104 extend obliquely upward like an open umbrella, dispersing the lifting force received at the center of the arch to the surrounding areas.

[0023] Specifically, the upper part of the steel support 104 is connected to the circular steel plate 105. The circular steel plate 105 connects multiple steel supports 104 into a whole, increasing the resistance to bottom heave and preventing excessive stress on a single steel support 104, which could lead to localized tensile cracks in the invert arch filling.

[0024] Specifically, the lower part of the umbrella-shaped support 103 is hinged to the Z-shaped steel frame 106, and the hinge point is set on the Z-shaped steel frame 106, dividing the Z-shaped steel frame 106 into two independent force-bearing parts symmetrical along the umbrella-shaped support 103.

[0025] Specifically, the corners of the Z-shaped steel frame 106 are rotatably hinged, and the bottom is rigidly connected to the inverted arch reinforcement and the anti-buoyancy anchor rod 110. As shown in the figure, the Z-shaped steel frame 106 mainly includes a horizontal bar and two outwardly inclined diagonal bars on both sides. The middle part of the horizontal bar is hinged to the umbrella-shaped support 103. The horizontal bar and the two diagonal bars are all hinged. The bottom of the two diagonal bars is connected to the anti-buoyancy anchor rod 110 and the inverted arch reinforcement.

[0026] When the umbrella-shaped support 103 is lifted, the hinge point connected to it on the Z-shaped steel frame 106 will rise accordingly. However, the bottom of the Z-shaped steel frame 106 will rise more slowly or not at all under the protection of the inverted arch reinforcement and the anti-buoyancy anchor rod 110. Therefore, the bottom rigid connection point will show a relatively downward movement trend relative to the middle hinge point. The movement trends of both will force the corner point of the Z-shaped steel frame 106 to move downward.

[0027] Specifically, the middle of the U-shaped steel frame 106 is rigidly connected to the portal-shaped steel frame 107, which in turn is rigidly connected to the umbrella-shaped support 103, as shown in the figure. The portal-shaped steel frame 107 mainly includes a horizontal bar and two vertical bars on both sides. The horizontal bar of the portal-shaped steel frame 107 passes through multiple steel supports 104, and the bottom ends of the vertical bars on both sides are rigidly connected to the middle of the diagonal bars on both sides of the U-shaped steel frame 106. Therefore, the portal-shaped steel frame 107 transmits the downward tendency force of the U-shaped steel frame 106 to the umbrella-shaped support 103, thereby suppressing the bulging of the umbrella-shaped support 103.

[0028] Specifically, the portal-shaped steel frame 107 is rigidly connected to the figure-eight steel frame 108, and the bottom of the figure-eight steel frame 108 is rigidly connected to the inverted arch reinforcement. Specifically, as shown in the figure, the figure-eight steel frame 108 mainly includes two outwardly inclined diagonal bars. The upper ends of the diagonal bars are rigidly connected to the middle part of the vertical bar of the portal-shaped steel frame 107, further fixing the portal-shaped steel frame 107 and increasing the support structure's resistance to bottom heave.

[0029] Specifically, the V-shaped steel frame 108 is rigidly connected to the hollow grouting anchor rod 109. The hollow grouting anchor rod 109 is driven deep into the surrounding rock to form an integral load-bearing structure with the surrounding rock, thus fixing the support assembly in the invert arch filling.

[0030] Specifically, three anti-buoyancy anchor rods 110 are installed in the surrounding rock at the bottom of the invert arch center. They are rigidly connected to the umbrella-shaped support 103 and the Z-shaped steel frame 106 through the invert arch reinforcement, respectively, to suppress the heave of the support body and improve the anti-bottom heave capacity of the tunnel invert arch.

[0031] The anti-bottom heave tunnel invert support method of this embodiment can improve the anti-bottom heave capacity of the tunnel invert, reduce the floating and cracking of the invert and invert filling, and prevent bottom heave damage to the invert structure.

Claims

1. A tunnel invert support structure for preventing bottom heave, comprising an invert primary support (100), an invert secondary lining (101), and an invert filler (102), characterized in that: The invert arch filling (102) is provided with an umbrella-shaped support (103), which is arranged vertically on a certain cross section of the tunnel and connects the invert arch primary support (100), the invert arch secondary lining (101) and the invert arch filling (102). The umbrella-shaped support (103) has multiple steel supports (104) on its upper part. The multiple steel supports (104) expand obliquely upward in the filling of the invert arch. The multiple steel supports (104) disperse the lifting force on the center of the invert arch to the surrounding area like an open umbrella. The upper part of the steel support (104) is connected to the edge of the circular steel plate (105). The circular steel plate (105) connects multiple steel supports (104) into a whole. The umbrella-shaped bracket (103), the steel support (104) and the circular steel plate (105) together form a complete umbrella-shaped support structure.

2. The anti-bottom heave tunnel invert support structure according to claim 1, characterized in that, There are 6 steel supports (104), and the circular steel plate (105) is higher in the middle and lower around the edges.

3. The anti-bottom heave tunnel invert support structure according to any one of claims 1-2, characterized in that, The umbrella-shaped support (103) is hinged to the Z-shaped steel frame (106) in the middle. The hinge point is set in the middle of the Z-shaped steel frame (106), dividing the Z-shaped steel frame (106) into two independent force-bearing parts symmetrical along the umbrella-shaped support (103). The corner of the Z-shaped steel frame (106) itself is a rotatable hinge.

4. The anti-bottom heave tunnel invert support structure according to claim 3, characterized in that, The bottom of the zigzag steel frame (106) and the umbrella-shaped support (103) are respectively connected to the corresponding anti-buoyancy anchor rod (110), and the connection point is rigidly connected by the inverted arch steel reinforcement.

5. The anti-bottom heave tunnel invert support structure according to claim 3, characterized in that, The top of the umbrella-shaped support (103) is rigidly connected to the portal-shaped steel frame (107), and multiple steel supports (104) pass through the middle of the portal-shaped steel frame (107). The bottom ends of the portal-shaped steel frame (107) are rigidly connected to the middle of the two sides of the zig-shaped steel frame (106).

6. The anti-bottom heave tunnel invert support structure according to claim 5, characterized in that, The middle of the two sides of the portal-shaped steel frame (107) is rigidly connected to the upper ends of the two sides of the figure-eight steel frame (108), and the lower end of the figure-eight steel frame (108) is connected to the inverted arch reinforcement.

7. The anti-bottom heave tunnel invert support structure according to claim 6, characterized in that, The lower end of the V-shaped steel frame (108) is connected to the hollow grouting anchor rod (109), and the V-shaped steel frame (108) and the hollow grouting anchor rod (109) are simultaneously rigidly connected to the inverted arch reinforcement.

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