A kind of dark excavation tunnel support structure

Abstract

The embodiment of the present application provides a dark-excavated tunnel support structure, which relates to the field of tunnel engineering and is used to solve the problems of poor rigidity and poor adaptability of dark-excavated tunnel support structures. The dark-excavated tunnel support structure includes a box assembly, which includes at least one box structure, the box structure extends along the circumference of the tunnel, and an excavation channel is formed on the box structure, and the excavation channel runs through two opposite side walls of the box structure along the extension direction of the tunnel. The box structure is used to be installed at the rear of multiple jacking machines arranged along the circumference of the tunnel, and the outer contour of the box structure in the extension direction of the tunnel is located within the total excavation contour. During the excavation process of multiple jacking machines, the box structure moves forward synchronously with the multiple jacking machines, providing forward thrust for the excavation of the jacking machines, and finally supports the holes excavated by the multiple jacking machines to form the lining of the tunnel. The dark-excavated tunnel support structure is used to ensure the construction safety, construction settlement and service life reliability of large-span dark-excavated tunnels.

Description

Technical Field

[0001] The present application relates to the technical field of tunnel engineering, and in particular to a dark-excavated tunnel support structure. Background Art

[0002] The tunnel excavation methods in related technologies mainly include the pipe-curtain tunnel excavation method and the MMST (Multi-Micro shield tunnel) method. The pipe-curtain tunnel excavation method is to arrange multiple large-diameter circular steel pipes along the circumference of the tunnel before tunnel excavation. The large-diameter steel pipes extend along the extension direction of the tunnel. The multiple large-diameter steel pipes are connected in sequence to form a tunnel support structure for supporting the rock and soil outside the tunnel. The MMST method, that is, the multi-micro shield tunnel method, is to use multiple micro shield machines to arrange multiple steel box structures with rectangular cross sections along the circumference of the tunnel before tunnel excavation. The multiple steel box structures are connected in sequence to form a tunnel support structure for supporting the rock and soil outside the tunnel.

[0003] However, for the pipe curtain dark excavation method, multiple circular steel pipes connected in sequence will have more joints, and the joints are weak links, which easily lead to poor rigidity of the dark excavation tunnel support mechanism. For the MMST method, the geological conditions applicable to the construction of micro-shield machines are limited, and the construction process is complex and has poor adaptability. Moreover, the cross-section of the steel box made by the micro-shield machine can generally only be a regular shape, such as a rectangle or a circle. Although the steel box with a rectangular cross-section can extend a certain length in the circumference of the tunnel, which is conducive to reducing the number of joints, if the dark excavation tunnel support mechanism is formed by connecting multiple rectangular steel boxes in sequence, the shape of its cross-section will be greatly restricted, which will in turn greatly restrict the cross-sectional shape of the tunnel. In the related art, the actual application case is only a tunnel with a rectangular cross-section, which has poor applicability. In addition, compared with the dark excavation tunnel support structure with an arc cross-section, the dark excavation tunnel support structure with a rectangular cross-section is poorly stressed and has poor rigidity. Therefore, the dark excavation tunnel support structure in the related art has the problems of poor rigidity and poor applicability. Summary of the invention

[0004] In view of this, an embodiment of the present application provides a dark-excavated tunnel support structure and a construction method to solve the problems of poor rigidity and poor adaptability of the dark-excavated tunnel support structure.

[0005] To achieve the above-mentioned purpose, an embodiment of the present application provides a dark-excavated tunnel support structure, which includes a box assembly, the box assembly includes at least one box structure, the box structure extends along the circumference of the tunnel and is used to form the lining of the tunnel, an excavation channel is formed on the box structure, the excavation channel runs through two opposite side walls of the box structure along the extension direction of the tunnel, the box structure is used to be installed on multiple pipe jacking machines arranged along the circumference of the tunnel, when the multiple pipe jacking machines are excavating, the box structure is supported in the holes excavated by the multiple pipe jacking machines to form the lining of the tunnel.

[0006] Furthermore, the excavation profiles of every two adjacent pipe jacking machines intersect, and the excavation profiles of a plurality of pipe jacking machines are combined to form a total excavation profile, and the outer profile of the box structure in the tunnel extension direction is located within the total excavation profile.

[0007] Furthermore, the interior of the box structure is filled with a concrete layer.

[0008] Furthermore, the box structure includes a box body and a supporting structure. The supporting structure is located in the box body. The supporting structure is supported between two side surfaces of the box body arranged along the height direction. The supporting structure and the concrete layer form a steel-concrete composite structure.

[0009] Furthermore, the support structure includes a plurality of first sub-support structures, the plurality of first sub-support structures extend along the extension direction of the tunnel, the plurality of first sub-support structures are arranged at intervals along the circumference of the tunnel, and an excavation channel is formed between two adjacent first sub-support structures.

[0010] Furthermore, the first sub-support structure is a rib structure.

[0011] Furthermore, the first sub-support structure includes a plurality of first columns, and the plurality of first columns are arranged along an extension direction of the tunnel.

[0012] Furthermore, the support structure also includes a second sub-support structure, which extends along the circumference of the tunnel. The second sub-support structure is located between two adjacent first sub-support structures. An excavated through hole is formed on the second sub-support structure, and the excavated through hole passes through the second sub-support structure along the extension direction of the tunnel.

[0013] Furthermore, the second sub-support structure includes a plurality of second columns, the plurality of second columns are arranged at intervals along the circumference of the tunnel, and the excavation through hole is formed between two adjacent second columns.

[0014] Furthermore, the second sub-support structure is a rib structure.

[0015] Further, the box assembly extends in a ring shape, or the box assembly has an opening along the circumference of the tunnel.

[0016] Furthermore, the box assembly includes a plurality of box structures, and the plurality of box structures are arranged along the circumference of the tunnel and are fixedly connected in sequence.

[0017] Furthermore, in two adjacent box structures, a card slot is formed on one, and a card plate is formed on the other. Both the card slot and the card plate extend along the circumference of the tunnel, and the card plate is inserted into the card slot.

[0018] Furthermore, among two adjacent box structures, an opening communicating with the interior of the box structure is formed on one box structure, the opening is located at one end of the box structure close to the other box structure and faces the other box structure, and one end of the other box structure close to the opening extends into the opening, so that the two box structures are fixedly connected.

[0019] Furthermore, a filling layer is filled between the inner walls of the holes excavated by the multiple pipe jacking machines and the outer wall of the box structure.

[0020] Furthermore, a shear-resistant member extending along the inner wall of the box structure is arranged on the inner wall of the box structure.

[0021] The dark-excavated tunnel support structure provided by the embodiment of the present application, the box structure is used to form the tunnel lining to support the rock and soil outside the tunnel. The box structure extends along the circumference of the tunnel, which is conducive to reducing the number of joints connected in sequence by multiple box structures, and thus is conducive to making the dark-excavated tunnel support structure have a higher rigidity. The box structure is constructed by multiple pipe jacking machines, that is, the box structure is prefabricated first, and then driven by multiple pipe jacking machines to extend into the rock and soil outside the tunnel. The construction is relatively convenient and the applicable geological conditions are relatively wide. Moreover, the box structure is prefabricated first, so that the shape of the box structure will not be greatly restricted. The box structure can be extended along a straight line, that is, the cross-section is rectangular, or it can be extended along an arc, or even along a circular ring, etc. The staff has a greater degree of design freedom. The staff can design the shape of the box structure relatively freely according to the shape of the cross-section of the tunnel to be excavated. The shape of the tunnel will not be greatly restricted, and the dark-excavated tunnel support structure has good applicability. In addition, the box structure can be prefabricated into various shapes, which is also beneficial for the staff to improve the stress of the dark-excavated tunnel support structure according to the actual situation, thereby facilitating the dark-excavated tunnel support structure to have better rigidity. Therefore, the dark-excavated tunnel support structure provided by the embodiment of the present application has better rigidity and applicability, and can solve the problem of poor rigidity and poor applicability of the dark-excavated tunnel support structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of a dark tunnel support structure in one embodiment of the present application;

[0023] Figure 2This is a structural schematic diagram of a box structure in an embodiment of the present application installed on a pipe jacking machine;

[0024] Figure 3 This is a structural schematic diagram of a box structure in another embodiment of the present application installed on a pipe jacking machine;

[0025] Figure 4 This is a structural schematic diagram of a box structure in another embodiment of the present application installed on a pipe jacking machine;

[0026] Figure 5 This is a structural schematic diagram of a box structure in an embodiment of the present application installed in a hole;

[0027] Figure 6 This is a structural schematic diagram of another embodiment of the present application in which a box structure is installed in a hole;

[0028] Figure 7 It is a structural schematic diagram of a box structure filled with concrete in one embodiment of the present application.

[0029] Reference numerals:

[0030] 01-tunnel; 02-pipe jacking machine; 03-hole; 11-box structure; 111-excavation passage; 112-box body; 113-support structure; 1131-first sub-support structure; 1132-second sub-support structure; 2-concrete layer; 3-filling layer; 4-secondary lining. DETAILED DESCRIPTION

[0031] It should be noted that, in the absence of conflict, the embodiments and technical features in the embodiments of the present application can be combined with each other, and the detailed description in the specific implementation method should be understood as an explanation of the purpose of the present application and should not be regarded as an improper limitation on the present application.

[0032] In the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more.

[0033] In addition, in the embodiments of the present application, directional terms such as "up", "down", "left" and "right" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to the changes in the orientation of the components in the drawings.

[0034] In the embodiments of the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0035] In the embodiments of the present application, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0036] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0037] There are two main tunnel excavation methods: open-cut and dark-cut. In the open-cut method, during the construction process, excavation is first carried out from the surface downward to form a foundation pit or trench, and then the tunnel body is built in the foundation pit or trench, and finally the tunnel body is backfilled with soil to complete the construction. In the dark-cut method, during the construction process, the ground is not dug up, and the construction is completed by digging a hole underground. Compared with the open-cut method, the dark-cut method has the advantages of small footprint, small amount of excavation, and less impact on surrounding facilities, but the disadvantage is that the construction is relatively difficult, especially during the excavation process, it is easy to cause problems such as ground subsidence and face deformation.

[0038] To address this problem, related technologies have proposed the pipe-curtain tunneling method and the MMST method. The pipe-curtain tunneling method is to arrange multiple large-diameter circular steel pipes along the circumference of the tunnel before tunnel excavation. The large-diameter steel pipes extend along the extension direction of the tunnel. Multiple large-diameter steel pipes are connected in sequence to form a tunnel support structure for supporting the rock and soil outside the tunnel to avoid deformation of the face during tunnel excavation. The MMST method is to use multiple small shield machines to arrange multiple steel box structures with rectangular cross sections along the circumference of the tunnel before tunnel excavation. Multiple steel box structures are connected in sequence to form a tunnel support structure for supporting the rock and soil outside the tunnel.

[0039] However, for the pipe curtain dark excavation method, multiple circular steel pipes connected in sequence will have more joints, and the joints are weak links, which easily lead to poor rigidity of the dark excavation tunnel support mechanism. For the MMST method, the geological conditions applicable to the construction of micro-shield machines are limited, and the adaptability is poor. Moreover, the cross-section of the steel box made by the micro-shield machine can generally only be a regular shape, such as a rectangle or a circle. Although the steel box with a rectangular cross-section can extend a certain length in the circumference of the tunnel, it is beneficial to reduce the number of joints. However, if the dark excavation tunnel support mechanism is formed by connecting multiple rectangular steel boxes in sequence, the shape of its cross-section will be greatly restricted, which will in turn greatly restrict the cross-sectional shape of the tunnel. In the related art, the actual application case is only a tunnel with a rectangular cross-section, which has poor applicability. Moreover, compared with the dark excavation tunnel support structure with an arc cross-section, the dark excavation tunnel support structure with a rectangular cross-section is less stressed and has poor rigidity. Therefore, the dark excavation tunnel support structure in the related art has the problems of poor rigidity and poor applicability.

[0040] In view of this, please refer to Figure 1 and Figure 2 The embodiment of the present application provides a dark-excavated tunnel support structure. The dark-excavated tunnel support structure includes a box assembly, which includes at least one box structure 11. The box structure 11 extends along the circumference of the tunnel 01 and is used to form the lining of the tunnel 01. An excavation channel 111 is formed on the box structure 11. The excavation channel 111 runs through two opposite side walls of the box structure 11 along the extension direction of the tunnel 01. The box structure 11 is used to be installed on multiple jacking machines 02 arranged along the circumference of the tunnel 01. When the multiple jacking machines 02 are excavating, the box structure 11 is supported in the holes 03 excavated by the multiple jacking machines 02 to form the lining of the tunnel 01.

[0041] In the dark-excavated tunnel support structure provided in the embodiment of the present application, the box structure 11 is used to form the lining of the tunnel 01 to support the rock and soil outside the tunnel 01. The box structure 11 extends along the circumference of the tunnel 01, which is conducive to reducing the number of joints connected in sequence by multiple box structures 11, and thus is conducive to making the dark-excavated tunnel 01 support structure have higher rigidity. The box structure 11 is constructed by multiple pipe jacking machines 02, that is, the box structure 11 is prefabricated first, and then driven by multiple pipe jacking machines 02 to extend into the rock and soil outside the tunnel 01. The construction is relatively convenient and applicable to a wide range of geological conditions. Moreover, the box structure 11 is prefabricated in advance, so that the shape of the box structure 11 will not be greatly restricted. The box structure 11 can be extended along a straight line, that is, the cross-section is rectangular, or it can be extended along an arc, or even extended along a circular ring, etc. The staff has a large degree of design freedom. The staff can design the shape of the box structure 11 relatively freely according to the shape of the cross-section of the tunnel 01 to be excavated. The shape of the tunnel 01 will not be greatly restricted, and the dark tunnel 01 support structure has good applicability. In addition, the box structure 11 can be prefabricated into various shapes, which is also beneficial for the staff to improve the stress conditions of the dark tunnel support structure according to actual conditions, and then it is beneficial for the dark tunnel support structure to have good rigidity. Therefore, the dark tunnel support structure provided in the embodiment of the present application has good rigidity and applicability, and can solve the problems of poor rigidity and poor applicability of the dark tunnel support structure.

[0042] Please note that, please refer to Figure 1 and Figure 2 The extension direction of the tunnel 01 is the driving direction or pedestrian direction in the tunnel 01, and the excavation directions of the multiple pipe jacking machines 02 are parallel to the extension direction of the tunnel 01. The multiple pipe jacking machines 02 are arranged along the circumference of the tunnel 01, so that the holes 03 excavated by the multiple pipe jacking machines 02 extend along the circumference of the tunnel 01. The holes 03 excavated by the multiple pipe jacking machines 02 refer to the total holes formed by combining the holes excavated by each pipe jacking machine 02. In the extension direction of the tunnel 01, the outer contour formed by the arrangement and combination of the multiple pipe jacking machines 02 matches the outer contour of the box structure 11, so that the box structure 11 can be installed in the holes 03 excavated by the multiple pipe jacking machines 02. Before the soil in the tunnel 01 is excavated, multiple pipe jacking machines 02 move forward synchronously in the excavation direction during the excavation process, and the box structure 11 moves forward with the multiple pipe jacking machines 02. The waste soil and gravel excavated by the pipe jacking machines 02 are discharged from the box structure 11 through the excavation channel 111 in the opposite direction of the excavation direction. Finally, the box structure 11 is supported in the hole 03 excavated by the multiple pipe jacking machines 02 to form the lining of the tunnel 01. After the construction of the supporting structure of the dark excavation tunnel 01 is completed, the soil in the tunnel 01 is excavated to complete the construction of the tunnel 01.

[0043] Preferably, in some embodiments, the excavation profiles of each two adjacent pipe jacking machines 02 intersect, the excavation profiles of multiple pipe jacking machines 02 are combined to form a total excavation profile, and the outer profile of the box structure 11 in the extension direction of the tunnel 01 is located within the total excavation profile. It should be noted that the excavation profile of a single pipe jacking machine 02 is the same as the outer profile of the cross section of the hole excavated by the single pipe jacking machine 02, and the cross section of the hole excavated by the single pipe jacking machine 02 is the cross section of the hole in the vertical direction of the excavation direction. The total excavation profile is the same as the outer profile of the cross section of the hole 03 excavated by multiple pipe jacking machines 02. The excavation profiles of each two adjacent pipe jacking machines 02 intersect, that is, the holes excavated by each two adjacent pipe jacking machines 02 are connected, and the outer profile of the box structure 11 in the extension direction of the tunnel 01 is located within the total excavation profile, which facilitates the installation of the box structure 11 in the hole 03 excavated by multiple pipe jacking machines 02.

[0044] Please note that, please refer to Figure 2 and Figure 3 The box assembly can be either annularly extended or have openings along the circumference of tunnel 01. Please refer to Figure 2 The box assembly extends in a ring shape, that is, the box assembly completely surrounds Tunnel 01 along the circumference of Tunnel 01, and the box assembly has a better support effect on the tunnel face. Please refer to Figure 3 The box assembly has an opening along the circumference of the tunnel 01, that is, the staff can use the box assembly to support the location with poor geological conditions according to the geological conditions outside the tunnel 01, and the location with good geological conditions can be supported without the box assembly, so as to save materials, reduce construction costs and reduce construction difficulty. Generally, when the box assembly has an opening along the circumference of the tunnel 01, the box assembly has an arch structure, that is, the box assembly has an opening on the lower side along the circumference of the tunnel 01.

[0045] Please note that, please refer to Figure 2 , Figure 3 and Figure 4 The box assembly may include only one box structure 11 or multiple box structures 11. Figure 2 and Figure 3 The box assembly only includes a box structure 11, and the box assembly does not have joints. The box structure 11 has good rigidity and good support effect, and is suitable for use in tunnels with small cross sections. Please refer to Figure 4 The box assembly includes a plurality of box structures 11, which are arranged along the circumference of the tunnel 01 and are fixedly connected in sequence. Providing a plurality of box structures 11 is conducive to reducing the length of a single box structure 11 along the circumference of the tunnel 01, which is conducive to reducing the construction difficulty, and is suitable for use in the case where the cross section of the tunnel 01 is large.

[0046] The length of the box structure 11 extending along the circumference of the tunnel 01 can be determined comprehensively based on multiple factors such as the cross-sectional area of ​​the tunnel 01, the rigidity of the supporting structure of the dark excavated tunnel 01, the resistance of the box structure 11 extending into the rock and soil, the mass of the box structure 11, and the operability of hoisting. The staff can determine the number of box structures 11 based on the length of the box structure 11 along the circumference of the tunnel 01.

[0047] There are many implementation forms for fixing and connecting multiple box structures 11 in sequence. For example, in some embodiments, one of the two adjacent box structures 11 is formed with a slot and the other is formed with a card plate. Both the slot and the card plate extend along the circumference of the tunnel 01, and the card plate is inserted into the slot. In such a structural form, the two adjacent box structures 11 are connected by a mortise and tenon structure, the connection is relatively stable, and the construction is relatively convenient. In other embodiments, in the two adjacent box structures 11, an opening connected to the inside of the box structure 11 is formed on one box structure 11, the opening is located at one end of the box structure 11 close to the other box structure 11, and faces the other box structure 11, and the end of the other box structure 11 close to the opening extends into the opening, so that the two box structures 11 are fixedly connected. In such a structural form, in the two adjacent box structures 11, one box structure 11 directly extends into the inside of the other box structure 11, the contact area between the two adjacent box components is large, and the connection is relatively stable. On this basis, in some embodiments, the interiors of all box structures 11 can be connected, so that when filling materials such as concrete into the box structure 11, the concrete and other materials can flow in the entire box assembly, facilitating construction.

[0048] In some embodiments, waterproof filling is further provided between two adjacent box structures 11. The waterproof filling is beneficial to improving the sealing of the connection between the two adjacent box structures 11.

[0049] In some embodiments, after the tunnel 01 is excavated, the two adjacent box structures 11 may be reinforced by bolting or welding, so that the dark-excavated tunnel support structure has better rigidity, which is helpful to avoid stratum deformation.

[0050] Furthermore, in order to facilitate the construction of the box structure 11, in some embodiments, the box structure 11 includes a plurality of box sections, and the plurality of box sections are arranged along the extension direction of the tunnel 01. With such a structural form, the plurality of box sections are constructed in sequence and connected in sequence to finally form the box structure 11, which is conducive to reducing the difficulty of construction. Specifically, during the construction of the box structure 11, the plurality of box sections of each box structure 11 are sequentially pushed into the holes 03 excavated by the plurality of pipe jacking machines 02, and the box section at the rear pushes the box section at the front to move forward. It should be noted that the forward movement is movement in the excavation direction. On this basis, in some embodiments, two adjacent box sections of each box structure 11 are welded and connected.

[0051] It should be noted that the length of the box section along the extension direction of the tunnel 01 can be determined by weight, lifting capacity and construction operability. Preferably, in some embodiments, the length of the box section along the extension direction of the tunnel 01 is 2 to 3 meters.

[0052] Further, in order to facilitate the construction of the box structure 11, please refer to Figure 5 and Figure 6 The inner wall of the hole 03 dug by the multiple pipe jacking machines 02 and the outer wall of the box structure 11 are filled with a filling layer 3. It can be understood that, please refer to Figure 5 and Figure 6 The box structure 11 extends along the circumference of the tunnel 01 to be excavated. In order to allow the box structure 11 to smoothly enter the rock and soil outside the tunnel 01, the holes 03 excavated by the multiple pipe jacking machines 02 will have a certain gap with the outer wall of the box structure 11. In the process of the box structure 11 extending into the holes 03 excavated by the multiple pipe jacking machines 02, the filling layer 3 is constructed in the gap between the holes 03 and the outer wall of the box structure 11, which is conducive to preventing the formation from deforming. Preferably, in some embodiments, the filling layer 3 is made of mud or sand mixed with mud. The rigidity of the mud or the sand mixed with mud is relatively low, which enables the filling layer 3 to support the inner wall of the hole 03 without causing a large obstacle to the movement of the box structure 11 extending into the hole 03. On this basis, in some embodiments, after the box structure 11 is installed in the hole 03, that is, the box structure 11 is inserted into the hole 03 and remains relatively static with the hole 03, the mud or sand mixed with the mud can be replaced with a material with greater rigidity such as cement mortar, etc., so that the installation of the box structure 11 in the hole 03 is more stable, which is conducive to improving the support effect.

[0053] Furthermore, in order to improve the stress condition of the box structure 11, a shear member extending along the inner wall of the box structure 11 is provided on the inner wall of the box structure 11. The shear member can be implemented in various forms, for example, it can be a steel bar extending along the wall of the box structure 11, it can also be a plurality of reinforcing ribs arranged on the wall of the box structure 11 in a mesh shape, it can also be a plurality of T-shaped members arranged on the wall of the box structure 11, etc., the extension direction of the T-shaped member is parallel to the wall of the box structure 11, and the plurality of T-shaped members are arranged along the wall of the box structure 11.

[0054] For further information, please refer to Figure 3 , Figure 4 and Figure 7 In order to improve the stress of the box structure 11 and increase the rigidity of the box structure 11, in some embodiments, the box structure 11 is filled with a concrete layer 2. Specifically, during the construction of the support structure of the dark excavated tunnel 01, the box structure 11 is driven by multiple pipe jacking machines 02 to extend into the rock and soil outside the tunnel 01. The waste soil and gravel excavated by the pipe jacking machines 02 are discharged from the box structure 11 through the excavation channel 111 in the opposite direction of the excavation direction. After the extension of the box structure 11 is completed, that is, the box structure 11 is installed in the hole 03 excavated by the multiple pipe jacking machines 02 and no longer moves relative to the hole 03, concrete is filled into the box structure 11 to form a concrete layer 2. It should be noted that in the process of filling the box structure 11 with concrete, the concrete can either completely fill the entire box or not fill the box.

[0055] On the basis of the concrete layer 2 filled inside the box structure 11, please refer to Figure 5 , Figure 6 and Figure 7 In some embodiments, the box structure 11 includes a box body 112 and a support structure 113. The support structure 113 is located inside the box body 112. The support structure 113 is supported between two side surfaces of the box body 112 arranged along the height direction. The support structure 113 is used to form a steel-concrete composite structure with the concrete layer 2. With such a structural form, the support structure 113 can, on the one hand, enhance the compressive stiffness of the box structure 11, improve the supporting effect of the box structure 11 on the heading, reduce the stratum deformation during the excavation of the tunnel 01, and the reliability of the tunnel 01 during its service life; on the other hand, it can be used to form a steel-concrete composite structure with the concrete layer 2, reducing the construction difficulty of the steel-concrete composite structure. It should be noted that the height direction of the box body 112 is perpendicular to the extension direction of the tunnel 01 and the cross-sectional outer contour of the tunnel 01.

[0056] It should be noted that the box body 112 refers to the structure on the box structure 11 for forming a cavity, and the support structure 113 is located in the cavity. After the box structure 11 is installed in the holes 03 excavated by multiple pipe jacking machines 02, concrete is filled into the cavity.

[0057] Specifically, during the construction of the supporting structure of the dark excavated tunnel 01, after the box structure 11 is installed in the holes 03 excavated by the plurality of pipe jacking machines 02, concrete can be filled into the box structure 11, and the filled concrete will automatically form a reinforced concrete structure with the support structure 113. The provision of the support structure 113 makes it unnecessary for the workers to enter the box structure 11 after the box structure 11 is installed in the holes 03, and to build a reinforced concrete structure for combining with the concrete layer 2 to form a steel-concrete composite structure in a narrow space, which helps to reduce the difficulty of construction.

[0058] It should be noted that for the pipe curtain dark excavation method, after multiple circular steel pipes are pushed into the rock and soil body and arranged circumferentially along the tunnel to be excavated 01, in order to form a steel-concrete composite structure, workers need to enter the steel pipes to cut the steel pipes, tie the steel bars, and pour concrete. Due to the limited space inside the pipe, construction is more difficult and the construction quality is difficult to guarantee. Moreover, the diameter design of the steel pipe must not only consider the rigidity of the steel pipe, but also the operating space of the workers, which can easily cause waste of materials and make the construction cost too high. The dark excavation tunnel 01 support structure in the embodiment of the present application does not require workers to enter the box structure 11 in the process of forming the steel-concrete composite structure. The construction is relatively easy, and there is no need to reserve a large construction operation space in the box structure 11, which is conducive to reducing material loss and saving costs. For the MMST method, the micro shield machine cannot directly make a support structure 113 for combining with the concrete layer 2 in the rectangular steel box, and workers are still required to enter the rectangular steel box to build steel bars. In the embodiment of the present application, the box structure 11 is pushed into the rock and soil by the pipe jacking machine 02. Before the box structure 11 enters the rock and soil, the support structure 113 has been formed. After the box structure 11 enters the rock and soil, concrete can be directly filled into the box structure 11.

[0059] In some embodiments, please refer to Figure 5 and Figure 6The support structure 113 includes a plurality of first sub-support structures 1131, which extend along the extension direction of the tunnel 01, and are arranged at intervals along the circumference of the tunnel 01, and the excavation channel 111 is formed between two adjacent first sub-support structures 1131. With such a structural form, the plurality of first sub-support structures 1131 can fully support the two side surfaces of the box body 112 arranged along the height direction, so that the box body 112 has greater rigidity. The plurality of first sub-support structures 1131 extend along the extension direction of the tunnel 01, and are arranged at intervals along the circumference of the tunnel 01. On the one hand, an excavation channel 111 is formed between two adjacent first sub-support structures 1131, and the excavation channel 111 has the same extension direction as the tunnel 01, which is conducive to the smooth flow of waste rock and crushed soil generated during the excavation process of the pipe jacking machine 02, and on the other hand, it is also conducive to the formation of a stable steel-concrete composite structure between the plurality of first sub-support structures 1131 and the concrete layer 2. Preferably, in some embodiments, the first sub-support structure 1131 is a rib plate structure. In some other embodiments, the first sub-support structure 1131 may include a plurality of first columns, and the plurality of first columns are arranged along the extension direction of the tunnel 01 .

[0060] On the basis that the excavation channel 111 is formed between two adjacent first sub-support structures 1131, in some embodiments, please refer to Figure 2 , Figure 3 and Figure 4 , multiple pipe jacking machines 02 are arranged in one-to-one correspondence with multiple excavation channels 111. In this way, waste soil and gravel generated during the excavation process of the pipe jacking machine 02 can flow out of the box structure 11 through the corresponding excavation channels 111, which is conducive to smooth flow of waste soil and gravel, and reduces resistance during the advancement of the pipe jacking machine 02.

[0061] In some embodiments, please refer to Figure 5 and Figure 6The support structure 113 also includes a second sub-support structure 1132, which extends along the circumference of the tunnel 01. The second sub-support structure 1132 is located between two adjacent first sub-support structures 1131. The second sub-support structure 1132 is formed with an excavation through hole, which penetrates the second sub-support structure 1132 along the extension direction of the tunnel 01. With such a structural form, the second sub-support structure 1132 can further enhance the rigidity of the box structure 11, and is conducive to the support structure 113 and the concrete layer 2 forming a more stable steel-concrete composite structure. The second sub-support structure 1132 is formed with an excavation through hole to meet the need that the waste rock and crushed soil generated during the excavation process of the pipe jacking machine 02 can flow along the extension direction of the tunnel 01 to be discharged from the box structure 11. On this basis, preferably, in some embodiments, the second sub-support structure 1132 is a rib plate structure. In some other embodiments, the second sub-support structure 1132 may include a plurality of second columns, and the plurality of second columns are arranged at intervals along the circumference of the tunnel 01, and an excavated through hole is formed between two adjacent second columns.

[0062] Of course, in some other embodiments, the support structure 113 may also be implemented in other forms, such as the support structure 113 includes a plurality of third sub-support structures 113, the third sub-support structures 113 extend in a direction perpendicular to the extension direction of the tunnel 01, the plurality of third sub-support structures 113 are arranged in the extension direction of the tunnel 01, and through holes are formed on the third sub-support structures 113 to meet the needs of soil excavation and slag removal. On this basis, in some embodiments, a fourth sub-support structure 113 is arranged between two adjacent third sub-support structures 113, and the fourth sub-support structure 113 extends in the extension direction of the tunnel 01.

[0063] In some other embodiments, the supporting structure 113 may not be provided in the box body 112, and a steel bar structure may be provided at the bottom of the box body 112. The steel bar structure may be formed integrally with the box body 112, or may be built by workers entering the box body 112 after the box body 112 is formed. The steel bar structure is used to form a steel-concrete composite structure with the concrete layer 2. Specifically, after the box structure 11 is installed in the hole 03, when the workers fill the box structure 11 with concrete, the concrete will flow to the bottom of the box structure 11 under the action of gravity, and form a steel-concrete composite structure with the steel bar structure at the bottom of the box structure 11. In this way, compared with forming a steel-concrete composite structure in the entire box, the purpose of saving materials, reducing construction costs, saving construction time, etc. can be achieved. This method can be adopted when the stiffness and strength of the supporting structure of the dark tunnel 01 meet the requirements. It should be noted that, in the process of filling the box body 112 with concrete, the concrete may be filled completely inside the box body 112 or may not be filled completely inside the box body 112, as long as the volume of the concrete is sufficient to form a steel-concrete composite structure with the steel structure.

[0064] In addition, please refer to Figure 1 The supporting structure of the dark-excavated tunnel 01 provided in the embodiment of the present application can be used only as the advance support of the tunnel 01. The advance support can be either temporary support or permanently retained after the tunnel 01 is excavated; it can also be used as the advance support and initial support of the tunnel 01, that is, after the tunnel 01 is excavated, the initial support is not constructed, and the secondary lining 4 is directly constructed on the inner wall of the tunnel 01 to complete the construction of the tunnel 01; it can also be used as the advance, initial support and secondary lining 4 of the tunnel 01, that is, after the tunnel 01 is excavated, the initial support and secondary lining can be constructed without construction. The staff can determine the functional positioning of the supporting structure of the dark-excavated tunnel 01 according to the use function, construction environment, durability requirements, etc. of the tunnel 01, and determine the length of the box structure 111 in the height direction according to the functional positioning of the supporting structure of the dark-excavated tunnel 01.

[0065] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A dark tunnel support structure, characterized in that: The invention comprises a box assembly, wherein the box assembly comprises a plurality of box structures, wherein the box structures extend along the circumference of the tunnel, the plurality of box structures are arranged along the circumference of the tunnel and are fixedly connected in sequence to form the lining of the tunnel, the interiors of the plurality of box structures are all connected, an excavation channel is formed on the box structure, and the excavation channel runs through two opposite side walls of the box structure along the extension direction of the tunnel; the plurality of box structures are used to be installed on a plurality of pipe jacking machines arranged along the circumference of the tunnel, the plurality of pipe jacking machines synchronously advance along the excavation direction during the excavation process, the plurality of box structures advance together with the plurality of pipe jacking machines, and the plurality of box structures are supported in holes excavated by the plurality of pipe jacking machines to form the lining of the tunnel; The excavation profiles of every two adjacent pipe jacking machines intersect, and the excavation profiles of a plurality of pipe jacking machines are combined to form a total excavation profile, and the outer profile of the box structure in the tunnel extension direction is located within the total excavation profile.

2. The dark tunnel support structure according to claim 1, characterized in that: The interior of the box structure is filled with a concrete layer.

3. The dark tunnel support structure according to claim 2 is characterized in that: The box structure includes a box body and a supporting structure. The supporting structure is located in the box body and supported between two side surfaces of the box body arranged in the height direction. The supporting structure and the concrete layer form a steel-concrete composite structure.

4. The dark tunnel support structure according to claim 3 is characterized in that: The support structure includes a plurality of first sub-support structures, which extend along the extension direction of the tunnel and are arranged at intervals along the circumference of the tunnel. The excavation channel is formed between two adjacent first sub-support structures.

5. The dark tunnel support structure according to claim 4, characterized in that: The first sub-support structure is a rib plate structure.

6. The dark tunnel support structure according to claim 4, characterized in that: The first sub-support structure includes a plurality of first columns, and the plurality of first columns are arranged along an extension direction of the tunnel.

7. The dark tunnel support structure according to claim 4, characterized in that: The support structure also includes a second sub-support structure, which extends along the circumference of the tunnel. The second sub-support structure is located between two adjacent first sub-support structures. An excavated through hole is formed on the second sub-support structure, and the excavated through hole penetrates the second sub-support structure along the extension direction of the tunnel.

8. The dark tunnel support structure according to claim 7, characterized in that: The second sub-support structure includes a plurality of second columns, which are arranged at intervals along the circumference of the tunnel, and the excavation through hole is formed between two adjacent second columns.

9. The dark tunnel support structure according to claim 7, characterized in that: The second sub-support structure is a rib plate structure.

10. The dark tunnel support structure according to any one of claims 1 to 9, characterized in that: The box assembly extends in a ring shape, or has an opening along the circumference of the tunnel.

11. The dark tunnel support structure according to any one of claims 1 to 9, characterized in that: Among the two adjacent box structures, one is formed with a card slot, and the other is formed with a card plate. Both the card slot and the card plate extend along the circumference of the tunnel, and the card plate is inserted into the card slot.

12. The dark tunnel support structure according to any one of claims 1 to 9, characterized in that: Among the two adjacent box structures, one of the box structures is formed with an opening that is connected to the interior of the box structure. The opening is located at one end of the box structure close to the other box structure and faces the other box structure. One end of the other box structure close to the opening extends into the opening, so that the two box structures are fixedly connected.

13. The dark tunnel support structure according to any one of claims 1 to 9, characterized in that: A filling layer is filled between the inner walls of the holes excavated by the multiple pipe jacking machines and the outer wall of the box structure.

14. The dark tunnel support structure according to any one of claims 1 to 9, characterized in that: The inner wall of the box structure is provided with a shear-resistant member extending along the inner wall of the box structure.

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