Arch structure flue plate capable of adapting to long-term deformation of shield tunnel

Abstract

According to the arch structure flue plate capable of adapting to long-term deformation of the shield tunnel, the hinge joint is arranged in the arch structure flue plate, so that the problem that in the prior art, an arch structure flue plate cannot be coordinated with long-term elliptic change of the tunnel is solved; the arch structure flue plate and the tunnel main body are coordinated in long-term deformation in the long-term service process, and the stress state of the arch structure is always kept. According to the technical scheme, the flue plate bracket structure and tunnel main body structure deformation are coordinated, the whole life cycle stress state of the flue plate is improved, and the actual engineering application value of the arch structure flue plate is greatly improved.

Description

Technical Field

[0001] The utility model relates to an arch structure flue plate which can adapt to the long-term deformation of a shield tunnel and relates to the technical field of shield tunnel engineering. Background Art

[0002] Due to the advantages of large-section tunnels in transportation capacity, the overall cross-sectional size is on an upward trend. Among tunnel construction methods, the shield method is safe and efficient, and its segment assembly is consistent with the concept of building industrialization. With the development of shield manufacturing technology in my country, it has been widely used. Since 2007, my country's extra-long highway large-diameter shield tunnels with a diameter greater than 10m have developed rapidly. Among them, the Haitai Yangtze River Tunnel, which started construction in 2022, is the country's largest diameter (segment outer diameter 16m) and longest distance (9.3km) ultra-large diameter (>14m) extra-long highway shield tunnel.

[0003] The fire safety issue in long and large tunnels is an international problem. my country's long and large highway tunnels adopt a centralized smoke exhaust mode with better smoke exhaust performance, which is achieved through the smoke exhaust duct top partition structure. The smoke duct plate is the isolation layer in the tunnel structure that separates the driving channel from the smoke exhaust channel. It is a non-load-bearing component and is placed on the bracket. Typical tunnel sections at home and abroad are as follows: Figure 1 and Figure 2 shown.

[0004] As the diameter of the shield increases, the span of the flue plate also increases. Under the current simply supported structure, the bending moment in the span will increase significantly. As the diameter of the shield tunnel increases, the span of the flue plate gradually increases. The traditional simply supported flue plate has been adapted to the construction of large diameter shield tunnels. In order to seek a more efficient flue plate structure, patent ZL202310272995.6 discloses a flue plate bracket that can provide horizontal force, which replaces the traditional simply supported flue plate (such as Figure 3 As shown) Through structural system optimization, the arch structure flue plate is optimized (as shown Figure 4 (as shown), significantly reducing the mid-span bending moment of the flue plate. Through rational arch axis shape-finding, a stress state of pure axial compression with zero bending moment across the entire cross-section is achieved, thereby reducing the thickness of the flue plate. The core of this technical solution is the provision of brackets that constrain the horizontal displacement of the flue plate at both ends, thereby providing horizontal force and achieving the transition from a simply supported structure to an arched structure.

[0005] However, in the actual service process of the tunnel, tunnel ellipse often occurs. In the soil layer, the tunnel cross section has a tendency to increase in transverse diameter, causing the tunnel cross section to change from a circular shape to a transverse ellipse (referred to as ellipse). Figure 5As shown. In high-stress rock formations, when the lateral rock stress is too large, the tunnel section tends to increase in vertical diameter, forming a vertical ellipse. As the main structure of the tunnel deforms, the spacing between the left and right brackets supporting the flue plate will change, causing the flue plate structure to deform along with the main tunnel, as shown in the figure below. Figure 6 shown.

[0006] Although my country's national standards, including 7.4.2 of the "GBT51438-2021 Shield Tunnel Engineering Design Standard" and 16.0.5 of the "GB50446-2017 Specification for Construction and Acceptance of Shield Tunneling," set limits on tunnel deformation, tunnel elliptical deformation continues to develop in actual use and may exceed regulatory limits. However, the technical solution disclosed in Patent ZL202310272995.6 does not consider measures to coordinate with tunnel elliptical deformation. As the spacing between the brackets increases, the brackets not only fail to provide the horizontal thrust to achieve the arch effect, but are also prone to tearing the flue plate. When the spacing between the brackets decreases, the excessive horizontal thrust will cause a reverse bending moment at the mid-span of the flue plate.

[0007] Taking the optimized structure disclosed in patent ZL202310272995.6 as an example, under the design load, the mid-span axial force of the arch structure flue plate is 505kN and the bending moment is 4.64kN·m. According to the requirements of 7.4.2 of "GBT51438-2021 Shield Tunnel Engineering Design Standard", the maximum value of the tunnel ellipse is 2‰D and no more than 50mm. Assuming that the spacing between the left and right supports of the flue plate is only increased by 5mm at the flue plate, the internal force analysis of the same structure after support deformation is performed, and the bending moment and axial force distribution are as follows: Figure 7 and Figure 8 As shown in the figure, the mid-span bending moment is 154 kN·m and the mid-span axial force is 257 kN. Compared with the bending moment under the design load (4.64 kN·m), the bending moment has increased by two orders of magnitude, and the bending effect is significant. Compared with the axial force under the design load (505 kN), the axial force has increased by about 1 / 2, and the increase in axial force is also quite significant.

[0008] Obviously, in the existing technology, the arch-structured flue plate disclosed in Patent ZL202310272995.6 transforms the traditional bending beam structure flue plate into an axial compression arch structure flue plate through structural innovation. During tunnel construction and the initial stage, it can make good use of the good compressive properties of concrete to achieve lightweight size and reduced reinforcement. However, its structural form cannot adapt to the long-term deformation of the tunnel. Under long-term deformation of the tunnel, as the distance between the left and right supports of the flue plate increases, significant bending moment and axial force will be generated in the flue plate, endangering the safety of the structure. Therefore, it is necessary to develop an arched flue plate that is compatible with the long-term elliptical deformation of the tunnel. Utility Model Content

[0009] This utility model provides an arch-structured flue plate that can adapt to the long-term deformation of shield tunnels. By providing a hinged node in the arch-structured flue plate, this overcomes the existing problem of the arch-structured flue plate's inability to coordinate with the long-term elliptical deformation of the tunnel. This allows the arch-structured flue plate to coordinate with the long-term deformation of the tunnel body during long-term service, maintaining the arch structure's stress state. This technical solution enables the flue plate's corbel structure to coordinate with the deformation of the tunnel body structure, improving the flue plate's stress state throughout its life cycle and significantly enhancing the arch-structured flue plate's practical engineering application value.

[0010] The utility model provides an arch structure flue plate which can adapt to the long-term deformation of a shield tunnel. The arch structure flue plate comprises a left flue plate and a right flue plate, and the left flue plate and the right flue plate are rotatably hinged.

[0011] Preferably, the hinge node is arranged at the mid-span of the arch structure flue plate.

[0012] Furthermore, the connection between the left flue plate and the right flue plate is set as a concave surface, and the connection between the right flue plate and the left flue plate is set as a convex surface, and the curvature radius of the concave surface is greater than the curvature radius of the convex surface.

[0013] Preferably, a flexible joint is pre-embedded at the joint position of the left flue plate, and the flexible joint is anchored to the left flue plate.

[0014] Alternatively, the left side of the flexible joint is a circular flexible gasket with a concave shape, and its curvature radius is equal to the curvature radius of the protrusion at the right flue plate joint.

[0015] Furthermore, a metal wrapping layer is provided on the contact surface of the left flue plate and the right flue plate.

[0016] Preferably, the metal wrapping layer is a steel plate.

[0017] Preferably, the thickness of the steel plate is equal to 1 / 20 of the thickness of the flue plate.

[0018] Furthermore, the right flue plate joint is an enlarged joint.

[0019] Preferably, indicator marks of different colors are inlaid on the enlarged head.

[0020] The beneficial effects of the utility model are:

[0021] This utility model provides an arch-structured flue plate that can adapt to the long-term deformation of shield tunnels. By providing a hinged node in the arch-structured flue plate, this overcomes the existing problem of the arch-structured flue plate's inability to coordinate with the long-term elliptical deformation of the tunnel. This allows the arch-structured flue plate to coordinate with the long-term deformation of the tunnel body during long-term service, maintaining the arch structure's stress state. This technical solution enables the flue plate's corbel structure to coordinate with the deformation of the tunnel body structure, improving the flue plate's stress state throughout its life cycle and significantly enhancing the arch-structured flue plate's practical engineering application value.

[0022] (1) This technology releases the mid-span bending moment by adding a rotating hinge point to the arch structure flue plate of the existing technology (patent ZL202310272995.6), and changes the two-hinged arch force model in the existing technology (such as Figure 11 ) is optimized to a three-hinge arch load model (e.g. Figure 12 ), so that the arch structure flue plate can adapt to the long-term deformation of the main structure of the tunnel. When the corbel moves with the main structure of the tunnel, the flue plate can still maintain the stress characteristics of the arch structure (i.e. mainly compression), thereby greatly improving the applicability of the arch structure flue plate.

[0023] (2) The flexible hinged joint of the flue plate proposed in the present invention can not only release the bending moment to transmit the axial force, but also has a sealing and airtight function, thereby preventing the smoke above the flue plate from leaking into the space below through the gap at the hinge point during a tunnel fire, thereby causing smoke damage.

[0024] (3) The flexible hinged node of the flue plate proposed in the present invention has an angle indication function. Without the need for external monitoring means, the rotation angle of the hinged node can be directly reflected through the angle indication device, which indirectly reflects the displacement of the brackets at both ends and the elliptical deformation of the tunnel main structure, thereby realizing performance monitoring of the entire service process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are used to provide a further understanding of the present invention and constitute a part 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. In the drawings:

[0026] Figure 1 It is a typical cross section of a large-diameter shield tunnel with existing technology in China;

[0027] Figure 2 It is a typical cross section of a large-diameter shield tunnel using existing foreign technology;

[0028] Figure 3 It is a traditional simply supported structure flue plate;

[0029] Figure 4It is the arch structure flue plate disclosed in patent ZL202310272995.6;

[0030] Figure 5 This is a schematic diagram of the shield tunnel ellipse;

[0031] Figure 6 This is a schematic diagram of the flue plate deforming along with the main structure of the tunnel;

[0032] Figure 7 The bending moment distribution of the arch structure flue plate under support deformation in the prior art;

[0033] Figure 8 The axial force distribution of the flue plate under support deformation in the prior art;

[0034] Figure 9 This is a three-hinged arch flue plate structure of the utility model;

[0035] Figure 10 The utility model is a three-hinged arch flue plate with a hinged node located in the middle;

[0036] Figure 11 This is a structural analysis model of the utility model of a three-hinged arch flue plate with a hinged node in the middle under support deformation;

[0037] Figure 12 The axial force distribution of the three-hinged arch flue plate with the hinge node in the middle under the action of support deformation and load;

[0038] Figure 13 The bending moment distribution of the three-hinged arch flue plate with the hinge node in the middle under the action of support deformation and load;

[0039] Figure 14 It is the hinged node of the flue plate of the utility model;

[0040] Figure 15 This is a rigid hinged node with steel plate protection in the utility model;

[0041] Figure 16 It is a flexible hinge node of the utility model;

[0042] Figure 17 It is a chimney plate hinge node with an enlarged head in the utility model;

[0043] Figure 18 It is a hinged node of a steel plate-clad flue plate with an enlarged head of the utility model;

[0044] Figure 19 It is a hinged node of a flexible flue plate with an enlarged head of the utility model;

[0045] Figure 20The utility model is an enlarged head flexible flue plate hinge node with a deformation indication function. DETAILED DESCRIPTION

[0046] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0047] Example 1

[0048] The utility model provides an arch structure flue plate which can adapt to the long-term deformation of a shield tunnel. A hinge node is set in the arch structure flue plate, and the hinge node can be located at any position of the flue plate, such as Figure 9 shown.

[0049] Example 2

[0050] Example 2 is based on Example 1. For ease of construction, the middle hinge node can be located in the middle. Preferably, the hinge node is located in the middle of the span (e.g. Figure 10 As shown), at this time, the hinge point only needs to transmit axial force, without transmitting shear force, and the force is relatively simple.

[0051] When the hinge node is in the middle (i.e. Figure 11 The structural form shown in the figure is used to analyze the stress of the arch structure disclosed in Patent ZL202310272995.6. The component size information and load information are exactly the same as those in Patent ZL202310272995.6. The support deformation UX = 50mm (i.e., calculated according to the maximum value required by the specification). Figure 11 shown.

[0052] Under the combined action of load and support deformation, the axial force distribution and bending moment distribution in the component are as follows: Figure 12 and Figure 13 The mid-span axial force is 512.9 kN, which is essentially the same as the 505 kN mid-span axial force for the two-hinge arch in Patent ZL202310272995.6. Its maximum bending moment is 354 N·m, and its influence can be almost ignored. The rotation angle of the mid-span hinge node is θ = 0.0629.

[0053] This technology releases the mid-span bending moment by adding a rotating hinge point to the arch structure flue plate of the existing technology (patent ZL202310272995.6), and changes the two-hinge arch force model of the existing technology (such as Figure 11 ) is optimized to a three-hinge arch load model (e.g. Figure 12), so that the arch structure flue plate can adapt to the long-term deformation of the main structure of the tunnel. When the corbel moves with the main structure of the tunnel, the flue plate can still maintain the stress characteristics of the arch structure (i.e. mainly compression), thereby greatly improving the applicability of the arch structure flue plate.

[0054] In summary, under the influence of load and support deformation, the stress state of the overall structure is basically the same as that of the two-hinged arch flue plate. It is still a mainly compressive component, but it can adapt to the long-term deformation of the tunnel.

[0055] Example 3

[0056] Example 3 is further designed based on Example 1. The flue plate is divided into a left flue plate 1 and a right flue plate 2 by a hinge node. The connection between the left flue plate 1 and the right flue plate 2 is set as a concave surface 11, and the connection between the right flue plate 2 and the left flue plate 1 is set as a convex surface 21. The curvature radius R2 of the concave surface 11 is greater than the curvature radius R1 of the convex surface 21. The hinge between the left flue plate 1 and the right flue plate 2 is as follows: Figure 14 shown.

[0057] Example 4

[0058] Example 4 Based on Example 3, to ensure the rotation ability of the node, the size of the node must meet the following requirements:

[0059]

[0060] Where: θ is the rotation angle of the hinge node when adapting to the deformation of the support; h is the thickness of the flue plate; R1 is the curvature radius of the concave surface 11; R2 is the curvature radius of the convex surface 21, R2>R1.

[0061] Example 4

[0062] Example 4 Based on Example 3, in order to solve the problem of local pressure at the contact position of the left flue plate 1 and the right flue plate 2, the contact surfaces of the concave surface 11 and the convex surface 21 are wrapped with steel plates, such as Figure 15 As shown, they are concave steel plate 12 and convex steel plate 22. When the thickness of concave steel plate 12 and convex steel plate 21 is not less than 4 mm, preferably h / 20, where h is the thickness of the flue plate.

[0063] Example 5

[0064] Example 5 is adjusted based on Example 3. In order to ensure the smoke sealing ability of the connection and the local contact pressure problem, a flexible joint 13 is buried in the concave surface 11. The material of the flexible joint 13 can be flexible materials such as high-temperature resistant rubber and modified asphalt, and is cast together with the left flue plate 1. Figure 16As shown, the left side of the flexible joint 13 is an anchoring piece for anchoring to the left flue plate 1; the left side of the flexible joint 13 is a circular flexible gasket, whose curvature radius is equal to the curvature radius of the convex surface 21. A flexible fireproof layer 3 is provided on the lower side of the flexible joint 13 to improve the fire resistance of the flexible joint 13.

[0065] Example 6

[0066] Example 6 Based on Example 3, in order to further improve the rotation ability of the hinge node and prevent the hinge node from slipping, the joint of the right flue plate 2 is made into an enlarged head 23. Figure 17 shown.

[0067] Example 7

[0068] Example 7 is based on Example 6. In order to avoid local pressure, the contact surface is covered with steel plates. Figure 18 shown.

[0069] Example 8

[0070] Example 8 Based on Example 7, in order to ensure the smoke sealing ability of the connection and the local contact pressure problem, the flexible joint 13 is buried in the concave surface 11, and the bottom of the flexible joint 13 is painted with fire retardant paint, such as Figure 19 shown.

[0071] Example 9

[0072] Example 9 is based on Example 8. In order to intuitively reflect the rotation of the hinge node, thereby inferring the elliptical deformation of the tunnel, realizing tunnel deformation monitoring, and controlling the deformation of the brackets at both ends of the flue plate, different colors of indicator marks 24 are embedded on the cylindrical enlarged head of the right flue plate, as shown in FIG. Figure 20 Tunnel inspectors can determine the rotation status of the hinge point by the color of the indicator strip at the junction of the left and right flue plates, and thus carry out tunnel rectification.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel, characterized by: The arch structure flue plate comprises a left flue plate and a right flue plate, and the left flue plate and the right flue plate are rotatably hinged.

2. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 1, characterized in that: The hinged node is set at the mid-span of the arch structure flue plate.

3. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 1, characterized in that: The connection between the left flue plate and the right flue plate is set as a concave surface, and the connection between the right flue plate and the left flue plate is set as a convex surface, and the curvature radius of the concave surface is greater than the curvature radius of the convex surface.

4. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 1, characterized in that: A flexible joint is embedded in the joint of the left flue plate, and the flexible joint is anchored to the left flue plate.

5. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 4, characterized in that: On the left side of the flexible joint is a circular flexible gasket with a concave shape, and its curvature radius is equal to the curvature radius of the protrusion at the right flue plate joint.

6. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 1, characterized in that: A metal wrapping layer is provided on the contact surface of the left flue plate and the right flue plate.

7. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 6, characterized in that: The metal covering is steel plate.

8. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 7, characterized in that: The thickness of the steel plate is equal to 1 / 20 of the thickness of the flue plate.

9. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 8, characterized in that: The right flue plate joint is an enlarged joint.

10. The arch-structured flue plate capable of adapting to long-term deformation of a shield tunnel according to claim 8, characterized in that: The enlarged head is inlaid with indicator marks of different colors.

Images