Efficient buffer structure capable of transforming existing buffer structure and suitable for newly-built tunnel

Abstract

The efficient buffer structure comprises a plurality of single-layer buffer structures which are communicated with one another, the length directions of the single-layer buffer structures are arranged in the extending direction of the tunnel, the center lines of the single-layer buffer structures in the length direction are collinear, and the center lines of the single-layer buffer structures in the length direction are collinear. One end of a single-layer buffer structure is connected to the portal of the tunnel in a sealed mode and is in butt joint with a main body structure of the tunnel. A plurality of single-layer buffer structures are designed at the entrance and exit of the tunnel, or a buffer structure is additionally arranged on the basis of an existing buffer structure of the tunnel portal to carry out strengthening transformation, the compression wave head wave pressure time gradient can be reduced through the design, and then the tunnel portal micro-pressure wave is effectively relieved; therefore, a good tunnel pneumatic effect relieving effect is achieved.

Description

Technical Field

[0001] The present invention relates to the field of tunnels, and more particularly to a high-efficiency buffer structure which can be used to transform existing buffer structures and is also suitable for building new tunnels. Background Art

[0002] The increase in train speed has facilitated transportation, but it has also brought about a series of scientific problems. For example, as the speed of trains increases, the aerodynamic effect becomes more significant, which will lead to increased driving resistance, increased noise inside the car, reduced passenger comfort, increased aerodynamic loads on ancillary facilities, significantly increased micro-pressure waves at tunnel entrances, and more obvious sonic booms. The low-frequency part of the micro-pressure wave at the tunnel entrance propagates very far in the form of infrasound, which may cause resonance in human organs and surrounding buildings, and the high-frequency part may form a sonic boom, affecting the normal life of surrounding residents.

[0003] The conventional practice is to set up a buffer structure at the tunnel entrance. The existing buffer structures mainly include equal-section type, expanded-section type, bevel type, trumpet type and combination type. No pressure relief holes are set on the side or top. Although the existing buffer structure can alleviate the micro-pressure wave effect at the tunnel entrance, the mitigation effect is limited. After the speed of existing railways is increased, some tunnels need to transform the tunnel entrance buffer structure to alleviate problems such as the increase in micro-pressure waves caused by the increase in train speed. New high-speed railway tunnels with higher speeds need to be designed with a buffer structure with higher mitigation efficiency.

[0004] Therefore, how to provide an efficient buffer structure that can not only transform the existing buffer structure but also be suitable for newly built tunnels so that it can overcome the above problems is an issue that technical personnel in this field urgently need to solve. Summary of the invention

[0005] In view of this, the present invention provides an efficient buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels.

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

[0007] An efficient buffer structure that can be used to transform existing buffer structures as well as to build new tunnels includes a plurality of interconnected single-layer buffer structures, wherein the length direction of the single-layer buffer structures is arranged along the extension direction of the tunnel, and the center lines of the plurality of single-layer buffer structures in the length direction are collinear, and one end of a single-layer buffer structure is sealed and connected to the tunnel entrance and butt-jointed with the main structure of the tunnel.

[0008] It can be seen from the above technical solution that, compared with the prior art, the present invention discloses a high-efficiency buffer structure that can not only transform existing buffer structures but also be suitable for newly built tunnels. The present invention designs multiple single-layer buffer structures at the entrance of the tunnel. The length direction of the single-layer buffer structure is arranged along the extension direction of the tunnel. The center lines of the multiple single-layer buffer structures in the length direction are collinear, and pressure relief holes are provided on the wall of the single-layer buffer structure. The above structure can greatly alleviate the compressibility effect of the train when entering the tunnel, and makes the pressure rise process of the compression wave more coherent and smooth, thereby reducing the maximum value of the compression wave pressure time gradient and the micro-air pressure wave intensity.

[0009] Preferably, a plurality of single-layer buffer structures are provided, and the plurality of single-layer buffer structures are nested together in sequence, and pressure relief holes are provided on the single-layer buffer structures.

[0010] Preferably, two single-layer buffer structures are provided, and one end of the innermost single-layer buffer structure is butted against the main structure of the tunnel.

[0011] Preferably, one end of the innermost single-layer buffer structure away from the tunnel is limited inside the outermost single-layer buffer structure.

[0012] Preferably, two single-layer buffer structures are provided, one end of one single-layer buffer structure is butted against the main structure of the tunnel, and the other end is butted against one end of another single-layer buffer structure.

[0013] Preferably, two single-layer buffer structures are provided and one of the single-layer buffer structures is trumpet-shaped, one end of the single-layer buffer structure is connected to the main structure of the tunnel, and the other end is connected to the small-diameter end of the trumpet-shaped single-layer buffer structure, and pressure relief holes are provided on the two single-layer buffer structures.

[0014] Preferably, an end wall of the single-layer buffer structure away from the tunnel is an inclined surface that gradually inclines inwards from bottom to top.

[0015] Preferably, the single-layer buffer structure is arranged vertically away from one end wall of the tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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 only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0017] Figure 1 It is an axonometric diagram of two single-layer buffer structures in the first layout in a highly efficient buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels;

[0018] Figure 2 It is an axonometric diagram of two single-layer buffer structures with rectangular cross-sections in the second layout of an efficient buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels;

[0019] Figure 3 It is an axonometric diagram of the second layout of two single-layer buffer structures with semicircular cross sections in an efficient buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels;

[0020] Figure 4 It is an axonometric diagram of two steel single-layer buffer structures in the second layout of the efficient buffer structure that can be used to transform existing buffer structures and also to build new tunnels;

[0021] Figure 5 It is an axonometric diagram of the third layout of two single-layer buffer structures in an efficient buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels;

[0022] Figure 6 It is an axonometric diagram of the fourth layout of two single-layer buffer structures in a highly efficient buffer structure that can be used to transform existing buffer structures and also be used for new tunnels;

[0023] Figure 7 This is the pressure time gradient diagram of the measuring point 200m outside the tunnel using the nested buffer structure;

[0024] Figure 8 This is the pressure-time gradient diagram of the measuring point 20m outside the tunnel using the nested buffer structure.

[0025] In the figure:

[0026] 1 is a single-layer buffer structure, and 2 is a pressure relief hole. DETAILED DESCRIPTION

[0027] 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, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The present invention discloses an efficient buffer structure that can be used to transform existing buffer structures and is also suitable for newly-built tunnels. A plurality of interconnected single-layer buffer structures 1 are designed at the tunnel entrance. The length direction of the single-layer buffer structures 1 is arranged along the extension direction of the tunnel. The center lines of the plurality of single-layer buffer structures 1 in the length direction are collinear. A pressure relief hole 2 can be opened on the tunnel wall of the single-layer buffer structure 1. The pressure relief hole 2 can be arranged on the side or top surface of the single-layer buffer structure 1.

[0029] There may be two single-layer buffer structures 1, and the two single-layer buffer structures 1 have different layouts:

[0030] The first is that two single-layer buffer structures 1 can be nested together from the inside to the outside;

[0031] The second is that two single-layer buffer structures 1 can be connected in sequence along the extension direction of the tunnel, and the cross-sectional areas of the two single-layer buffer structures 1 can be different or the same;

[0032] The third type is that two single-layer buffer structures 1 are connected in sequence along the extension direction of the tunnel, and the single-layer buffer structure 1 far away from the tunnel is trumpet-shaped;

[0033] The above design makes the pressure rise process of the compression wave in the tunnel more coherent and gentle, thereby reducing the maximum value of the compression wave pressure time gradient and the micro-pressure wave intensity, thereby achieving a good pressure relief buffering effect. At the same time, the buffer structure is simple and easy to construct;

[0034] In the prior art, there may be only one single-layer buffer structure 1 at the tunnel entrance. The present application can directly improve the existing buffer structure, that is, add a single-layer buffer structure 1 and open a pressure relief hole 2 on the existing single-layer buffer structure 1 without causing damage to the existing tunnel structure.

[0035] Example

[0036] See attached Figure 1-8 It is a schematic diagram of the overall and partial structures of an embodiment of the present invention.

[0037] The present invention specifically discloses an efficient buffer structure which can be used to transform existing buffer structures and is also suitable for newly built tunnels, including a plurality of interconnected single-layer buffer structures 1, the single-layer buffer structures 1 being made of concrete or metal, the length direction of the single-layer buffer structures 1 being arranged along the extension direction of the tunnel, the center lines of the plurality of single-layer buffer structures 1 in the length direction being collinear, one end of a single-layer buffer structure 1 being sealed and connected to the tunnel entrance and being connected to the main structure of the tunnel with an equal cross-section or an enlarged cross-section; a pressure relief hole 2 may be provided on the wall of the single-layer buffer structure 1, the shape of the pressure relief hole 2 and its position on the single-layer buffer structure 1 are not limited, and may be specifically determined according to the actual operation scenario. The pressure relief hole 2 in this embodiment is a rectangular hole.

[0038] In this embodiment, there are two single-layer buffer structures 1, and the two single-layer buffer structures 1 have the following layout forms:

[0039] The first type is that the inner and outer cross-sectional shapes of the two single-layer buffer structures 1 are the same, one single-layer buffer structure 1 is arranged on the outside of the other single-layer buffer structure 1, and there is a gap between the two single-layer buffer structures 1. One end of the innermost single-layer buffer structure 1 is connected to the main structure of the tunnel with the same cross-section or the expanded cross-section. Both single-layer buffer structures 1 are provided with a plurality of pressure relief holes 2, and the positions of the pressure relief holes 2 can be the side or the top of the single-layer buffer structure 1. One end of the outermost single-layer buffer structure 1 is sealed and connected to the end of the tunnel; the hole shapes and hole areas of the pressure relief holes 2 respectively located on the two single-layer buffer structures 1 can be the same or different; the end of the innermost single-layer buffer structure 1 away from the tunnel is limited to the inner side of the outermost single-layer buffer structure 1.

[0040] The second type is that one end of a single-layer buffer structure 1 is butted with a main structure of the tunnel of equal cross-section or an enlarged cross-section, and the other end is butted with one end of another single-layer buffer structure 1. The ends of the two single-layer buffer structures 1 are butted together by pouring concrete or plugging. The cross-sectional shape and cross-sectional area of ​​the two single-layer buffer structures 1 are the same, and pressure relief holes 2 are opened on the two single-layer buffer structures 1.

[0041] The third type is that each single-layer buffer structure 1 is provided with a plurality of pressure relief holes 2, one end of a single-layer buffer structure 1 is butted with the main structure of the tunnel with the same cross-section or an enlarged cross-section, and the other end is butted with one end of another single-layer buffer structure 1, and the ends of the two single-layer buffer structures 1 are butted together by pouring concrete or plugging; the cross-sectional area of ​​a single-layer buffer structure 1 closest to the tunnel is smaller than the cross-sectional area of ​​the other single-layer buffer structure 1.

[0042] The fourth type is that one single-layer buffer structure 1 is in a straight cylindrical shape, and the other single-layer buffer structure 1 is in a trumpet shape. The inner cross-sectional shape of the straight cylindrical single-layer buffer structure 1 is the same as the cross-sectional shape of the tunnel. One end of the straight cylindrical single-layer buffer structure 1 is butted with the main structure of the tunnel with the same cross-section, and the other end is butted with the small-diameter end of the trumpet-shaped single-layer buffer structure 1. The ends of the two single-layer buffer structures 1 are butted together by pouring concrete or plugging. Pressure relief holes 2 are provided on both single-layer buffer structures 1.

[0043] In the above-mentioned cases, the outer wall of the single-layer buffer structure 1 has a column protruding outward, and a pressure relief hole 2 is opened on the end wall of each column. The length direction of the column is perpendicular to the length direction of the single-layer buffer structure 1. This design is equivalent to separating the pressure relief hole 2 from the outer wall of the single-layer buffer structure 1, and there is a certain distance between the two to prevent dirt or rainwater from entering the pressure relief hole 2;

[0044] A protective net may be provided at the pressure relief hole 2 to prevent foreign matter or living things from entering the single-layer buffer structure 1 through the pressure relief hole 2; a baffle may be provided at the pressure relief hole 2 according to actual needs, thereby adjusting the buffer effect.

[0045] The single-layer buffer structure 1 is arranged vertically away from one end wall of the tunnel or is an inclined surface that gradually inclines inward from bottom to top.

[0046] According to the arrangement form of the first single-layer buffer structure 1, the aerodynamic effect of the train passing through the tunnel and the tunnel buffer structure is obtained through simulation calculation, and the influence of the pressure relief holes 2 on the buffer effect on the two single-layer buffer structures 1 is analyzed;

[0047] Are the pressure relief holes 2 on the two single-layer buffer structures 1 opened? What is the pressure time gradient at the measuring point 200m in the tunnel? Figure 7 As shown;

[0048] When the pressure relief holes 2 on the two single-layer buffer structures 1 are not opened, the compression wave effect caused by the train entering the tunnel in advance is superimposed on the compressibility effect when the train passes through the opening area, and the maximum value of the pressure time gradient increases instead;

[0049] When the pressure relief holes 2 on the two single-layer buffer structures 1 are both opened, the compressive effect caused by the train entering the buffer structure is further relieved, and the pressure-time gradient decreases;

[0050] When only the pressure relief hole 2 located on the innermost single-layer buffer structure 1 is opened, the first peak value of the pressure-time gradient will not change. It can be seen that in this case, the compressibility effect of the train completely entering the single-layer buffer structure 1 is slightly increased, but the compressibility effect of the train entering the tunnel is greatly weakened, the pressure rise process of the compression wave pressure is smoother, and the maximum value of the pressure-time gradient is 5.47 kPa / s, which is 16% lower than that of the conventional tunnel buffer structure with a hole on the top;

[0051] After the initial compression wave propagates to the tunnel exit, it radiates outward to generate micro-pressure waves. The intensity of the micro-pressure waves 20 m outside the tunnel is as follows: Figure 8 As shown. With this buffer structure, the micro-pressure wave at the entrance of a high-speed railway tunnel at a speed of 400 kilometers per hour can be reduced to below the standard value, which is 50Pa at a distance of 20 meters from the tunnel entrance. The design speed of existing high-speed railway tunnels is generally lower than 400 kilometers per hour, and only a single-layer buffer structure is set inside. It can be strengthened and renovated by adding an outer layer buffer or connecting the front end with an efficient buffer structure to meet the needs of railway speed increase.

[0052] It can be seen that the use of this tunnel buffer structure can not only greatly alleviate the compressibility effect when the train enters the tunnel, but also make the pressure rise process of the compression wave more coherent and smooth, thereby reducing the maximum value of the compression wave pressure time gradient and the micro-pressure wave intensity.

[0053] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0054] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An efficient buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels, characterized in that: It comprises a plurality of interconnected single-layer buffer structures, wherein the length direction of the single-layer buffer structures is arranged along the extension direction of the tunnel, the center lines of the plurality of single-layer buffer structures in the length direction are collinear, and one end of a single-layer buffer structure is sealed and connected to the tunnel entrance and butted against the main structure of the tunnel.

2. According to claim 1, a high-efficiency buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels is characterized in that: A plurality of single-layer buffer structures are provided, and the plurality of single-layer buffer structures are sleeved together in sequence, and pressure relief holes are provided on the single-layer buffer structures.

3. According to claim 2, a high-efficiency buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels is characterized in that: Two single-layer buffer structures are provided, and one end of the innermost single-layer buffer structure is butted against the main structure of the tunnel.

4. According to claim 3, a high-efficiency buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels is characterized in that: One end of the innermost single-layer buffer structure away from the tunnel is limited inside the outermost single-layer buffer structure.

5. According to claim 1, a high-efficiency buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels is characterized in that: There are two single-layer buffer structures, one end of one single-layer buffer structure is butted against the main structure of the tunnel, and the other end is butted against one end of another single-layer buffer structure.

6. According to claim 1, a high-efficiency buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels is characterized in that: There are two single-layer buffer structures, one of which is trumpet-shaped. One end of the single-layer buffer structure is connected to the main structure of the tunnel, and the other end is connected to the small-diameter end of the trumpet-shaped single-layer buffer structure. Pressure relief holes are opened on the two single-layer buffer structures.

7. According to claim 1, a high-efficiency buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels is characterized in that: The end wall of the single-layer buffer structure away from the tunnel is an inclined surface which gradually inclines inwards from bottom to top.

8. According to claim 1, a high-efficiency buffer structure that can be used to transform existing buffer structures and is also suitable for new tunnels is characterized in that: The single-layer buffer structure is arranged vertically away from one end wall of the tunnel.

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