Friction self-locking type tunnel segment structure and construction method

Abstract

The invention provides a friction self-locking type tunnel segment structure and a construction method, relates to the technical field of tunnel supporting structures, and aims to solve the problems of leakage hidden danger and connection failure of gaps caused by insufficient axial connection strength of existing shield segments. Locking of the locking block and the locking groove is achieved through annular rotation, the locking action is perpendicular to the locking limiting direction so that loosening and failure of the locking structure can be limited, the problems that a traditional connecting structure is inconvenient to arrange along an arc path and prone to loosening and failure are solved, and the connecting strength and stability of the annular piece are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel support structures, and in particular to a friction self-locking tunnel segment structure and a construction method. Background Art

[0002] During shield tunneling, the excavated portion of the shield needs to be supported. Currently, precast concrete segments are used as support structures. These segments are assembled into rings by the shield machine's robotic arm to support the excavated surrounding rock. Grouting is then injected between the ring segments and the surrounding rock to fill the gaps and form a stable support structure. The assembled shield segments are able to bear the external rock loads and prevent groundwater from seeping into the tunnel. As permanent support structures within the tunnel, the quality of the segments directly impacts the tunnel's safety and durability.

[0003] Currently, shield segments are often connected by bolts. During segment assembly, the circumferential segments are fixed first, followed by the axial segments. U-bolts are used to connect the rings, but due to assembly deviations, the U-bolts cannot pass smoothly through the curved holes. Once the segments are assembled, the fixed positions are difficult to adjust. While vibration and tapping can loosen the holes to allow for penetration, the holes are located at the edges of the segments, which can easily crack and cause failure. While ring displacement can be limited by retaining structures such as protrusions and grooves on the segment ends, their axial retaining capacity remains insufficient, resulting in loose axial joints and uncontrolled gaps between the rings, leading to leakage. When using a tensioning connection, the mortar filling the ring-to-ring joints can easily loosen and fall off, causing the connection to fail. Summary of the Invention

[0004] The purpose of the present invention is to address the defects of the existing technology and provide a friction self-locking tunnel segment structure and construction method. The segments corresponding to adjacent ring segments are connected by locking blocks and locking grooves. The locking of the locking blocks and locking grooves is achieved by circumferential rotation. The locking action is perpendicular to the locking limit direction, thereby limiting the loosening and failure of the locking structure, solving the problem that traditional connection structures are inconvenient to set along an arc path and are prone to loosening and failure, and improving the connection strength and stability of the ring segments.

[0005] The first object of the present invention is to provide a friction self-locking tunnel segment structure, which adopts the following scheme:

[0006] It comprises a first tube segment and a second tube segment butted together along the axial direction, one end of the first tube segment is provided with a connected locking groove and a guide groove, one end of the second tube segment is provided with a locking block adapted to the locking groove, the locking block moves circumferentially in the guide groove to be embedded in the locking groove, so that the end faces of the first tube segment and the second tube segment are abutted and connected; multiple first tube segments are spliced ​​along the circumferential direction to form a first ring segment, and multiple second ring segments are spliced ​​along the circumferential direction to form a second ring segment.

[0007] Furthermore, the locking groove is provided with a communicating receiving groove and a limiting groove, and the locking block is provided with a head and a neck, the head cooperates with the receiving groove, and the neck cooperates with the limiting groove, so that the locking block cooperates with the locking groove to form a locking.

[0008] Furthermore, the accommodating groove and the limiting groove are arranged in sequence along the circumferential direction of the first pipe segment, and the accommodating groove and the limiting groove are respectively connected to the guide groove.

[0009] Furthermore, the locking block is a gradual structure, so that the locking block is embedded in the locking groove to form an interference fit.

[0010] Furthermore, the first ring segment and the second ring segment are fitted together with their end faces and assembled with staggered seams, and the first pipe segment and the second pipe segment are connected in a one-to-one correspondence.

[0011] Furthermore, along the tunnel ring direction, matching convex parts and concave parts are provided between adjacent first pipe segments on the first ring segment, and matching convex parts and concave parts are provided between adjacent second pipe segments on the second ring segment. Multiple first pipe segments cooperate with the third pipe segment to form a closed ring, and multiple second pipe segments cooperate with the third pipe segment to form a closed ring.

[0012] Furthermore, a filler is provided in the guide groove to block the opening where the locking groove communicates with the guide groove.

[0013] Furthermore, a monitoring element is embedded in the filler, one opening of the guide groove is located on the axial end face of the first pipe segment, and the other opening is located on the radial inner wall of the first pipe segment.

[0014] A second object of the present invention is to provide a construction method for a friction-based self-locking tunnel segment structure, comprising:

[0015] Assembling the first tube segments to form a first ring segment;

[0016] Pick up a second pipe segment, insert the locking block on the second pipe segment into the guide groove, keep the second pipe segment in contact with the end surface of the first pipe segment, and rotate the second pipe segment so that the locking block enters the locking groove;

[0017] Pick up the next second tube segment and match it with another first tube segment of the first ring segment; connect all the second tube segments of the first ring segment into a ring to form a second ring segment.

[0018] Furthermore, a locking groove and a guide groove are also provided on the end of the second pipe segment away from the locking block, and the next group of second pipe segments are picked up to connect with the second ring segments that have formed a ring, so as to realize the continuous arrangement of the ring segments in the tunnel.

[0019] Compared with the prior art, the present invention has the following advantages and positive effects:

[0020] (1) In order to solve the problem that the axial connection strength of shield segments is insufficient, resulting in leakage hazards in the gap and connection failure, the segments corresponding to adjacent ring segments are connected by locking blocks and locking grooves. The locking of the locking blocks and locking grooves is achieved by circumferential rotation. The locking action is perpendicular to the locking limit direction, thereby limiting the loosening and failure of the locking structure. This solves the problem that the traditional connection structure is inconvenient to set along the arc path and is prone to loosening and failure, and improves the connection strength and stability of the ring segments.

[0021] (2) The segments on the ring segments at different axial positions are connected through locking grooves and locking blocks. The insertion position between the locking grooves and the locking blocks realizes a friction self-locking structure. The locking grooves, locking blocks and segments are prefabricated as a whole, realizing the splicing between the front and rear ring segments. It is no longer necessary to use multiple bolts for fixing. The operation is convenient and the installation is quick. An automated construction system can be formed in the later stage, thereby improving construction efficiency.

[0022] (3) The locking block is configured with a large head and a small neck structure, which can adapt to the large and small opening structure inside the locking groove to form a locking structure, keep the end face of the pipe segment in contact and constrain its movement along the axial direction of the ring segment to prevent failure of the mating position. A guide groove is provided to facilitate the locking block to enter the locking groove from the side, and the plug-in mating direction of the locking groove and the locking block is arranged separately from the constraint force direction to improve the connection stability.

[0023] (4) A guide groove is configured and connected to the locking groove. The guide groove temporarily accommodates the locking block so that the locking block can move toward the locking groove in the guide groove. After the matching is completed, a filling block is set in the guide groove as a limiting structure for the locking block to limit the locking block in the locking groove to prevent it from falling out and causing connection failure. At the same time, the locking groove can be used as an installation area according to needs, and the monitoring element can be buried in the filling block to obtain parameters during tunnel operation and monitor the environment in the tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0025] Figure 1 Schematic diagram of the axial connection of the ring sheets in Examples 1 and 2 of the present invention.

[0026] Figure 2Schematic diagram of the structure of the first tube segment in Examples 1 and 2 of the present invention.

[0027] Figure 3 Schematic diagram of the structure of the second pipe segment in Examples 1 and 2 of the present invention.

[0028] Figure 4 Schematic diagram of the structure of the filling block in Examples 1 and 2 of the present invention.

[0029] Figure 5 Schematic diagram of the structure of the third tube segment in Examples 1 and 2 of the present invention.

[0030] Among them, 1. first pipe segment; 2. second pipe segment; 3. third pipe segment; 4. locking groove; 5. guide groove; 6. locking block; 7. filling block. DETAILED DESCRIPTION

[0031] Example 1

[0032] In a typical embodiment of the present invention, Figure 1-Figure 5 As shown, a friction self-locking tunnel segment structure is given.

[0033] When constructing underground tunnels using the shield method, it's crucial to provide timely support for the excavated sections by the shield machine. This support structure typically consists of prefabricated concrete segments, assembled into rings by a robotic arm. The shield segments not only bear external soil loads and certain special loads but also prevent groundwater seepage. As permanent support structures within the tunnel, the quality of the segments directly impacts the tunnel's safety and durability, making them a crucial component of tunnel construction.

[0034] Currently, the primary method for connecting shield segments is bolting, with the circumferential segments secured first, followed by the axial segments (between rings). U-bolts are typically used, and workers manually tighten the bolts, resulting in low installation efficiency. Sometimes, improper bolt hole alignment can make it difficult to insert the bolts. On-site solutions typically involve hammering the bolts through the curved bolt holes, which carries the risk of cracking the concrete segments at the bolt holes.

[0035] In addition, the connection structure between the rings of the traditional tunnel segments has a poor axial connection effect, and there is still a risk of leakage in the gaps between the rings.

[0036] In this embodiment, a friction self-locking tunnel segment structure is proposed to solve the above problem. The structure can realize effective connection between rings through the locking block 6 and the locking groove 4 structure at the end of the segment, constrain the axial position between the ring segments in the tunnel, and avoid the uncontrollable increase of the gap between the end faces of the ring segments causing leakage and the damage caused by end face extrusion.

[0037] It can be understood that the locking block 6 cooperates with the locking groove 4 to constrain the axial stretching of the pipe segment, thereby preventing the gap between the pipe segments from increasing when the pipe segments are pulled axially. At the same time, when the locking block 6 abuts the locking groove 4, it can also constrain the axial extrusion of the pipe segment, bear the axial extrusion force, and thus avoid damage to the contact position of the end face of the pipe segment due to excessive force, thereby ensuring the effectiveness of the connection between the ring segments in both directions.

[0038] Specifically, such as Figure 1 The friction-locking tunnel segment structure shown in the figure primarily comprises multiple sets of segments. To facilitate the description of the connections between the segments, the two connected sets are referred to as the first segment and the second segment, respectively. The segments comprising the first segment are referred to as first segment 1, and the segments comprising the second segment are referred to as second segment 2. The first and second segments differ in position and orientation, but the corresponding first and second segments 1 and 2 have the same structure.

[0039] The first pipe segment 1 and the second pipe segment 2 are butt-jointed along the axial direction. A locking groove 4 and a guide groove 5 are provided at one end of the first pipe segment 1. A locking block 6 adapted to the locking groove 4 is provided at one end of the second pipe segment 2. The locking block 6 moves circumferentially in the guide groove 5 to be embedded in the locking groove 4, so that the end faces of the first pipe segment 1 and the second pipe segment 2 are abutted and connected.

[0040] It should be pointed out that since there are multiple groups of ring segments arranged in the tunnel, the ring segments are a continuous support structure formed by being connected in series in sequence. While one end of the first segment 1 cooperates with the second segment 2, the other end of the first segment 1 is connected to another group of ring segments, and the other end of the second segment 2 is connected to another group of segments. Therefore, one end of the first segment 1 is provided with a locking groove 4 and a guide groove 5, and the other end is also provided with a locking block 6; one end of the second segment 2 is provided with a locking block 6, and one end of the connecting rod is also provided with a locking groove 4 and a guide groove 5; so that a continuous support structure is formed after the segments are connected in series, in this embodiment, for the sake of convenience, the scheme is introduced by taking the docking of one end of the first segment 1 and one end of the second segment 2 as an example. For the sequential connection of multiple groups of ring segments, refer to the docking structure and docking process of the first segment 1 and the second segment 2 in this embodiment.

[0041] like Figure 1 As shown, multiple first segments 1 are spliced ​​together in the annular direction to form a first ring segment, and multiple second segments are spliced ​​together in the annular direction to form a second ring segment. The first ring segment and the second ring segment are connected by butting the first segment 1 and the second segment 2.

[0042] like Figure 2In the illustrated first tube segment 1, a locking groove 4 and a guide groove 5 are provided on the end surface of the first tube segment 1 that mates with the second tube segment 2. The locking groove 4 serves as a structure for mate with the locking block 6, and the guide groove 5 serves as a guide structure for the locking block 6 to mate with the locking groove 4. Specifically, the locking groove 4 is composed of a connected receiving groove and a limiting groove, and the locking block 6 is composed of a head and a neck. The head mates with the receiving groove, and the neck mates with the limiting groove, so that the locking block 6 mates with the locking groove 4 to form a locking state.

[0043] The accommodating groove and the limiting groove on the first pipe segment 1 are arranged in sequence along the circumferential direction of the first pipe segment 1, and the accommodating groove and the limiting groove are respectively connected to the guide groove 5. Figure 2 The locking groove 4 extends along the annular direction parallel to the arc line of the pipe segment to the guide groove 5. At the same time, the arc length corresponding to the position of the guide groove 5 is greater than the arc length corresponding to the position of the locking groove 4, so that the locking block 6 can be accommodated in the guide groove 5 and the locking block 6 can pass through the guide groove 5 into the locking groove 4.

[0044] In this embodiment, the arc length corresponding to the guide groove 5 is equal to twice the arc length of the locking groove 4. At the same time, the arc length corresponding to the locking groove 4 is consistent with the arc length corresponding to the locking block 6, so that they can be plugged in and matched.

[0045] The guide groove 5 is a recessed structure within the segment, forming a fan-shaped ring. The locking groove 4 is also a recessed structure within the segment, with a cross-section along the ring similar to that of the locking block 6, both of which are approximately in the shape of a "Γ". Furthermore, the locking block 6 has a gradual transition structure, allowing it to fit within the locking groove 4 with an interference fit. When the locking block 6 and the locking groove 4 engage, the mating surfaces form a frictional self-locking mechanism.

[0046] like Figure 3 As shown, the locking block 6 can be considered a slider extending along the annular direction of the segment and having a radial cross-section approximately in the shape of a "Γ". The locking block 6 cooperates with the locking groove 4 to form a locking structure. It is understood that the locking block 6 and the locking groove 4 can also adopt other matching structures, such as a dovetail structure, a trapezoidal structure, a partially circular structure, etc., as long as the structure can effectively restrict the axial range of motion of the segment.

[0047] like Figure 2 and Figure 3 As shown, the end faces of the first ring segment and the second ring segment are fitted together and staggered, and the first pipe segment 1 and the second pipe segment 2 are connected one by one; along the tunnel ring direction, matching convex parts and concave parts are provided between adjacent first pipe segments 1 on the first ring segment, and matching convex parts and concave parts are provided between adjacent second pipe segments 2 on the second ring direction.

[0048] In this embodiment, the convex portion and the concave portion are respectively a semi-cylindrical protrusion and a semi-cylindrical groove, which facilitate the circumferential positioning connection between the pipe segments in the same ring.

[0049] like Figure 1 、 Figure 2and Figure 4 As shown, after the locking groove 4 cooperates with the locking block 6 , the guide groove 5 forms a cavity, and a filler is set in the guide groove 5 to block the opening where the locking groove 4 connects to the guide groove 5 .

[0050] The filler can be an independently movable insert. After the first and second segments 1 and 2 are axially joined and rotated to the appropriate position, the insert is radially inserted into the remaining area of ​​the guide groove 5. The insert can be made of water-swelling rubber with a certain self-expansion coefficient. This not only completes the segment splicing, but also prevents water from seeping into the shield segments along the splice, thus providing a certain water-stopping effect.

[0051] A monitoring element is embedded in the filler. One opening of the guide groove 5 is located on the axial end face of the first pipe segment 1, and the other opening is located on the radial inner wall of the first pipe segment 1. The opening faces the inner side of the pipe segment, which is convenient for arranging the monitoring element and also for inserting the filler into the guide groove 5 later.

[0052] like Figure 1 、 Figure 5 As shown, a plurality of first tube segments 1 cooperate with the third tube segment 3 to form a closed ring, and a plurality of second tube segments 2 cooperate with the third tube segment 3 to form a closed ring.

[0053] by Figure 1 Taking the middle structure as an example, each set of ring segments can be divided into four pieces, three of which are identical in size and shape. The three identically sized segments in the first ring segment are first segments 1. In addition to these three segments, another segment with a smaller arc length than the other three first segments 1 is third segment 3. The ends of third segment 3 are not equipped with locking blocks 6 or locking grooves 4. Instead, they are provided with a semi-cylindrical groove and a semi-cylindrical protrusion at the locations where they circumferentially butt against first segment 1. Therefore, third segment 3 does not serve as a structure connecting segments between longitudinal rings. Instead, it fills the gaps left between each ring after the first segment 1 is placed, thus securing the circumferential segments.

[0054] Similarly, the three tube segments of the second ring segment with the same size are the second tube segments 2, and the second tube segments 2 are combined with another third tube segment 3 to form a ring.

[0055] Example 2

[0056] In another typical embodiment of the present invention, Figure 1-Figure 5 As shown, a construction method of a friction self-locking tunnel segment structure is given.

[0057] Assembling the first tube segment 1 to form a first ring segment;

[0058] Pick up a second pipe segment 2, insert the locking block 6 on the second pipe segment 2 into the guide groove 5, keep the second pipe segment 2 in contact with the end surface of the first pipe segment 1, and rotate the second pipe segment 2 so that the locking block 6 enters the locking groove 4;

[0059] Pick up the next second tube segment 2 and mate it with another first tube segment 1 of the first ring segment; connect all the second tube segments 2 of the first ring segment into a ring to form a second ring segment;

[0060] The end of the second pipe segment 2 away from the locking block 6 is also provided with a locking groove 4 and a guide groove 5. The next group of second pipe segments 2 is picked up to connect the second ring segments that have formed a ring, thereby realizing the continuous arrangement of the ring segments in the tunnel.

[0061] Specifically, in combination with Example 1 and Figure 1-Figure 5 , the above construction method specifically includes:

[0062] 1. Assume that the first ring of the first segment 1 has been fully assembled. The construction worker controls the segment assembly machine to pick up the second segment 2 and align the locking block 6 on the front side of the second segment 2 with the rear guide of the first segment 1. The segment assembly machine then pushes the second segment 2 forward a certain distance so that the locking block 6 on the front side inserts into the corresponding guide groove 5 of the first segment 1.

[0063] 2. Operate the segment assembly machine to rotate the second segment 2 clockwise a certain angle until the locking block 6 fits into the recessed locking groove 4. Because the front section of the Γ-shaped locking groove 4, i.e., the horizontal "-" portion, is slightly thinner than the corresponding portion of the locking block 6 in actual design, the locking block 6 achieves an interference fit with the locking groove 4, achieving frictional self-locking. In other embodiments, a gradual change in structure can also be used to achieve an interference fit.

[0064] 3. After the rotation is completed, the guide groove 5 of the first segment 1 is left empty due to the lack of a slider. Filler blocks 7 are then radially inserted into the guide groove 5, completely filling the entire guide groove 5 of the first segment 1. The longitudinal connection between the first segment 1 and the second segment 2 is complete. Since the filler blocks 7 can be made of water-swelling rubber, a material with a certain water absorption capacity and self-expansion coefficient, they achieve an interference fit with the guide groove 5 after insertion. Furthermore, the surface of the filler blocks 7 can be configured with raised threads to further secure the connection between the first segment 1 and the second segment 2.

[0065] 4. The first pipe segments 1 and the second pipe segments 2 connected front and back are called a group. Repeat the above operation twice to complete the longitudinal splicing of three identical groups of first pipe segments 1 and second pipe segments 2.

[0066] 5. At this time, the robot arm is controlled to pick up a third pipe segment 3 and insert it axially into the incomplete circular ring formed by the three second pipe segments 2, so that the second pipe segment 2 of the second ring is combined with the third pipe segment 3 to complete the ring assembly.

[0067] Used for axial connection between shield segment rings, this system relies on frictional self-locking between the locking block 6 and the locking groove 4, reducing construction steps and improving segment installation efficiency. The special shape of the locking groove 4 also provides higher tensile strength between the segments after tightening, surpassing existing bolt-type fastening methods. Furthermore, the special material of the filler block 7 prevents water seepage through the segments.

[0068] In other embodiments, the cavities formed by the assembled guide grooves 5 are filled with concrete slurry by injecting it radially from the openings of the guide grooves 5 at the edges of the first segment 1. Concrete slurry has a certain adhesive property, and after solidification and hardening, the longitudinal connection between the first segment 1 and the second segment 2 is further strengthened. This operation also eliminates the need for pre-preparation of filler blocks 7, reducing the number of pre-construction steps.

[0069] In other embodiments, considering the need to monitor initial deformation and long-term operational displacement of tunnel segments, displacement sensors can be built into the filler blocks 7. Once the filler blocks 7 are inserted into the guide slots 5, displacement sensors are embedded within both the first and second segments 1, 2 of each ring. Furthermore, because the sensors are located within the filler blocks 7 and protected by the outer casing, they are less susceptible to interference and damage from the tunnel environment, enabling long-term operation.

[0070] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A friction self-locking tunnel segment structure, characterized in that: It comprises a first tube segment and a second tube segment butted together along the axial direction, one end of the first tube segment is provided with a connected locking groove and a guide groove, one end of the second tube segment is provided with a locking block adapted to the locking groove, the locking block moves circumferentially in the guide groove to be embedded in the locking groove, so that the end faces of the first tube segment and the second tube segment are abutted and connected; multiple first tube segments are spliced ​​along the circumferential direction to form a first ring segment, and multiple second ring segments are spliced ​​along the circumferential direction to form a second ring segment.

2. The friction self-locking tunnel segment structure according to claim 1, characterized in that: The locking groove is provided with a communicating receiving groove and a limiting groove, and the locking block is provided with a head and a neck, the head cooperates with the receiving groove, and the neck cooperates with the limiting groove, so that the locking block cooperates with the locking groove to form a locking.

3. The friction self-locking tunnel segment structure according to claim 2, characterized in that: The accommodating groove and the limiting groove are arranged in sequence along the circumferential direction of the first pipe segment, and the accommodating groove and the limiting groove are respectively connected to the guide groove.

4. The friction self-locking tunnel segment structure according to claim 2, characterized in that: The locking block has a gradual structure, so that the locking block is embedded in the locking groove to form an interference fit.

5. The friction self-locking tunnel segment structure according to claim 1, characterized in that: The first ring segment and the second ring segment are fitted together at their end faces and assembled with staggered seams, and the first pipe segment and the second pipe segment are connected in a one-to-one correspondence.

6. The friction self-locking tunnel segment structure according to claim 1, characterized in that: Along the tunnel ring direction, adjacent first tube segments on the first ring segment are provided with matching convex parts and concave parts, and adjacent second tube segments on the second ring segment are provided with matching convex parts and concave parts. Multiple first tube segments cooperate with the third tube segment to form a closed ring, and multiple second tube segments cooperate with the third tube segment to form a closed ring.

7. The friction self-locking tunnel segment structure according to claim 1, characterized in that: A filler is provided in the guide groove to block the opening where the locking groove communicates with the guide groove.

8. The friction self-locking tunnel segment structure according to claim 7, characterized in that: A monitoring element is embedded in the filler. One opening of the guide groove is located on the axial end face of the first pipe segment, and the other opening is located on the radial inner wall of the first pipe segment.

9. A construction method for a friction self-locking tunnel segment structure, characterized in that: include: Assembling the first tube segments to form a first ring segment; Pick up a second pipe segment, insert the locking block on the second pipe segment into the guide groove, keep the second pipe segment in contact with the end surface of the first pipe segment, and rotate the second pipe segment so that the locking block enters the locking groove; Pick up the next second tube segment and match it with another first tube segment of the first ring segment; connect all the second tube segments of the first ring segment into a ring to form a second ring segment.

10. The construction method of the friction self-locking tunnel segment structure according to claim 9, characterized in that: The end of the second pipe segment away from the locking block is also provided with a locking groove and a guide groove, and the next group of second pipe segments is picked up to connect the second ring segments that have formed a ring, so as to realize the continuous arrangement of the ring segments in the tunnel.

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