Tunnel primary support structure

Abstract

The utility model relates to a tunnel primary support structure, which takes a wave-shaped retaining plate as a support main body, and the arrangement direction of wave crests and wave troughs of the wave-shaped retaining plate is arranged in the longitudinal direction of a tunnel, so that the wave-shaped retaining plate has the mechanical characteristic of small compression rigidity along the arrangement direction of the wave crests and the wave troughs; the longitudinal deformation and stress of the surrounding rock can be controlled; meanwhile, the annular displacement and stress generated by the surrounding rock are dynamically controlled through a special connection mode between the adjacent wave-shaped retaining plates in the retaining layer. That is to say, the supporting structure can dynamically respond to the deformation and stress of the surrounding rock from the longitudinal direction and the circumferential direction at the same time by means of the retaining layer formed by the wave-shaped retaining plates, and therefore the dynamic adaptability of the tunnel supporting structure can be improved, pressure can be evenly distributed, the self-bearing capacity of the surrounding rock can be effectively exerted, and the construction period can be shortened.

Description

Technical Field

[0001] The utility model relates to the technical field of tunnel support, in particular to an initial tunnel support structure. Background Art

[0002] During tunnel excavation, surrounding rocks with poor rock quality are often low in strength, easy to break, and easily unstable due to disturbance. Sometimes local or large-scale landslides and roof falls may occur, increasing the difficulty of construction and safety risks. In some cases, the surrounding rock may also contain high ground stress, which may cause rock bursts during excavation and pose a threat to construction safety. Therefore, the reasonable setting of tunnel support structures is particularly important to ensure the safety of construction personnel and the structural stability of the tunnel.

[0003] Traditional initial support structures mainly include shotcrete, steel arches, anchors and steel mesh, which together constitute a stable system for initial tunnel support. However, with the development of tunnel engineering, the geological conditions are becoming more and more complex. Traditional support structures have problems such as long construction period, lack of dynamic adaptability, uneven pressure distribution, low efficiency and insufficient support strength in a short period of time, making it difficult to meet the growing safety and adaptability requirements.

[0004] At the same time, tunnels in my country currently generally emphasize the deformation control function of passive support components such as steel arch frames. Traditional support measures cannot effectively and fully utilize the bearing capacity of the surrounding rock itself.

[0005] Therefore, in order to effectively exert the self-bearing capacity of the surrounding rock, it is very necessary to design a new type of support structure so that it can form a self-stabilizing structure while releasing most of the stress by controlling the deformation range of the surrounding rock. Utility Model Content

[0006] In view of this, the utility model provides a novel initial tunnel support structure, which can dynamically respond to the deformation and stress of the tunnel surrounding rock in both longitudinal and circumferential directions based on its own adaptive design.

[0007] The utility model discloses an initial support structure for a tunnel, comprising a retaining layer which is arranged facing the tunnel surrounding rock and forms an annular shape in the tunnel, and is characterized in that the retaining layer is constructed by connecting a plurality of corrugated retaining plates which have continuous wave crests and wave troughs to each other in the tunnel annular direction, and the corrugated retaining plates are arranged so that the arrangement direction of their own wave crests and wave troughs is in the longitudinal direction of the tunnel, so as to adapt to the deformation and stress of the tunnel surrounding rock in the longitudinal direction; and, in each retaining layer, annular overlapping parts are respectively provided between two annularly adjacent corrugated retaining plates, and the annular overlapping parts are connected to adjacent corrugated retaining plates by means of connecting holes and annular connecting members which cooperate with the connecting holes, and the connecting hole on the annular overlapping part of at least one of the adjacent corrugated retaining plates is a strip-shaped elongated hole, and is constructed together with the connecting member to allow the corrugated retaining plate to be relatively displaced when subjected to annular pressure, so as to adapt to the deformation and stress of the tunnel surrounding rock in the annular direction.

[0008] Based on the above structure, in the utility model, when the tunnel surrounding rock produces longitudinal deformation and stress, it can respond with the help of the mechanical characteristics of the corrugated retaining plate of the retaining layer with low compressive stiffness in the arrangement direction of its own wave crests and troughs. At the same time, when the tunnel surrounding rock produces circumferential deformation and stress, since the connecting hole on the circumferential overlap portion of at least one of the adjacent corrugated retaining plates of the retaining layer is a strip-shaped elongated hole, the corrugated retaining plate can produce relative displacement when subjected to circumferential pressure, thereby being able to adapt to the deformation and stress of the tunnel surrounding rock in the circumferential direction.

[0009] Furthermore, the strip-shaped elongated hole includes a positioning hole portion and a U-shaped interference hole portion communicating with the positioning hole portion, and the annular connecting member can extend from the positioning hole portion to form a connection between the annular overlapping portions of adjacent corrugated retaining plates; the strip-shaped elongated hole and the annular connecting member are jointly constructed such that when the corrugated retaining plate is not subjected to annular pressure, the annular connecting member is retained in the positioning hole portion, and when the corrugated retaining plate is subjected to annular pressure and exceeds the rated pressure, the annular connecting member can enter the U-shaped interference hole portion from the positioning hole portion under the action of pressure and form an interference fit with the U-shaped interference hole portion.

[0010] In a preferred embodiment, the strip-shaped elongated hole is arranged on the connecting portion of the corrugated retaining plate located below in the circumferential direction among the adjacent corrugated retaining plates, and the connecting hole on the connecting portion of the corrugated retaining plate located above in the circumferential direction among the adjacent corrugated retaining plates is a conformal hole adapted to the shape of the circumferential connecting piece. That is to say, among the two adjacent corrugated retaining plates of the retaining layer, the strip-shaped elongated hole is arranged on the circumferential overlapping portion of one of them, while the connecting hole conforming to the shape of the connecting piece is arranged on the circumferential overlapping portion of the other one. In this case, the positioning hole portion of the strip-shaped elongated hole is also conformed to the shape of the connecting piece, and the connecting piece passes through the positioning hole portion to form a connection with the connecting hole on the other corrugated retaining plate, thereby connecting two adjacent corrugated retaining plates; at the same time, the radial dimension of the connecting piece is larger than the orifice size of the U-shaped interference hole portion of the strip-shaped elongated hole, so that the connecting piece can be retained in the positioning hole portion, and when annular pressure occurs, the connecting piece can be forced into the U-shaped interference hole portion under the displacement of the corrugated retaining plate under the action of pressure, and form an interference fit with the U-shaped interference hole portion, thereby adapting to the annular deformation and stress of the tunnel surrounding rock.

[0011] Furthermore, each corrugated retaining plate of the retaining layer is connected to the surrounding rock of the tunnel through an anchor rod.

[0012] Furthermore, a plurality of retaining layers are arranged along the longitudinal direction of the tunnel, and there is a gap space between each retaining layer and the tunnel surrounding rock; a buffer layer is also included, and the buffer layer is arranged between the retaining layer and the tunnel surrounding rock in a manner of filling the gap space to adapt to the radial deformation and stress of the tunnel surrounding rock. That is, in a preferred embodiment, when the tunnel surrounding rock produces radial deformation (or displacement) and stress, the buffer layer densely filled between the surrounding rock and the retaining layer can also be used to relieve pressure and adapt; that is, in the present utility model, it is possible to dynamically respond to the deformation and stress of the surrounding rock from the radial, longitudinal and circumferential directions at the same time, thereby improving the dynamic adaptability of the tunnel support structure, evenly distributing the pressure, effectively exerting the self-bearing capacity of the surrounding rock, and shortening the construction period.

[0013] That is, based on the aforementioned overall structure, the support structure of the utility model can still maintain self-stability when subjected to longitudinal, radial and circumferential deformation stresses, and will not collapse due to surrounding rock deformation and stress.

[0014] Furthermore, a radial pressure collection device is provided on the contact surface between the buffer layer and the retaining layer for collecting data on the radial deformation pressure of the tunnel surrounding rock; and / or, a longitudinal pressure collection device is provided at an adjacent position of the retaining layer in the longitudinal direction of the tunnel for collecting data on the longitudinal deformation pressure of the tunnel surrounding rock.

[0015] Furthermore, it also includes a pressure data transmission device and a background control device, wherein the pressure data transmission device can receive the pressure data collected by the radial pressure collection device and / or the longitudinal pressure collection device, and transmit it to the background control device; the background control device can analyze and process the received pressure data, and can automatically issue an early warning in combination with the stress and / or displacement values ​​in the pressure data.

[0016] Furthermore, the buffer layer is formed by filling the gap between the tunnel surrounding rock and the retaining layer with high elastic spheres of equal particle size; the radius of the high elastic spheres of equal particle size is not greater than one tenth of the wave width of the corrugated retaining plate.

[0017] Furthermore, inflatable rubber pads are arranged at both ends of each annular retaining layer in the longitudinal direction of the tunnel to seal the gap between the retaining layer and the tunnel surrounding rock at the two end positions, so that highly elastic equal-size spheres can be injected into the gap space.

[0018] Furthermore, in the longitudinal direction of the tunnel, after the corresponding buffer layer of the next retaining layer between two adjacent retaining layers is constructed, the inflatable rubber pads sealing the ends at adjacent positions of the two adjacent retaining layers will be completely deflated and withdrawn to form a common buffer layer between the two adjacent retaining layers.

[0019] Beneficial effects: In the initial tunnel support structure of the utility model, the corrugated retaining plate is used as the main support body. Through the mechanical characteristics of the corrugated retaining plate with low compressive stiffness along the direction of the wave crests and troughs, the deformation and stress of the surrounding rock in the longitudinal direction can be controlled; at the same time, through the special connection method between adjacent corrugated retaining plates in the retaining layer, the circumferential displacement and stress generated by the surrounding rock can be dynamically controlled. In other words, the support structure of the utility model can dynamically respond to the deformation and stress of the surrounding rock in the longitudinal and circumferential directions at the same time by means of the retaining layer formed by the corrugated retaining plate, thereby improving the dynamic adaptability of the tunnel support structure, evenly distributing the pressure, effectively exerting the self-bearing capacity of the surrounding rock, and shortening the construction period.

[0020] The tunnel initial support structure and construction method of the utility model are disclosed in detail below in conjunction with the embodiments shown in the accompanying drawings and the accompanying drawing numbers. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The overall structural schematic diagram of the support structure of the utility model is shown.

[0022] Figure 2 A schematic diagram of the connection structure of the circumferential overlapping portions of the corrugated connecting plates adjacent in the circumferential direction in the retaining layer is shown. Similarly, the connection structure of the longitudinal overlapping portions of the corrugated retaining plates between the longitudinally adjacent retaining layers can be implemented with reference to this.

[0023] Figure 3The schematic diagram of the structure of the strip-shaped elongated hole on the annular overlap portion is shown. Similarly, the strip-shaped elongated hole on the longitudinal overlap portion can also be implemented by reference.

[0024] Figure 4 It is a simplified structural diagram of the intelligent monitoring system for tunnel displacement and deformation in the utility model. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0027] Figure 1 The overall structural diagram of the support structure of the utility model is shown. Figure 1 As shown, the utility model discloses an initial support structure for a tunnel, including a retaining layer 1 and a buffer layer 2. The retaining layer 1 is arranged facing the tunnel surrounding rock 4 and forms a ring in the tunnel. A plurality of retaining layers 1 are arranged along the longitudinal direction of the tunnel, and there is a gap space between each retaining layer 1 and the tunnel surrounding rock 4. The buffer layer 2 is arranged between the retaining layer 1 and the tunnel surrounding rock 4 in a manner of filling the gap space to adapt to the radial deformation and stress of the tunnel surrounding rock 4. The retaining layer 1 is constructed by connecting a plurality of corrugated retaining plates 3 having continuous wave crests and wave troughs to each other in the tunnel ring direction, and the corrugated retaining plates 3 are arranged with their own wave crests and wave troughs. The arrangement direction of the wave troughs is in the longitudinal direction of the tunnel to adapt to the deformation and stress of the tunnel surrounding rock 4 in the longitudinal direction; and, in each retaining layer 1, there are annular overlap portions 8 between the two circumferentially adjacent corrugated retaining plates 3, and the annular overlap portions 8 are connected to adjacent corrugated retaining plates 3 by means of connecting holes and annular connecting members 9 matched with the connecting holes. The connecting holes on the annular overlap portions of at least one of the adjacent corrugated retaining plates 3 are strip-shaped elongated holes 10, and are constructed together with the connecting members to allow the corrugated retaining plates 3 to be relatively displaced when subjected to annular pressure to adapt to the deformation and stress of the tunnel surrounding rock 4 in the circumferential direction.

[0028] The so-called corrugated retaining plate 3 refers to a corrugated plate body with multiple continuous crests and troughs. Since the arrangement direction of its own crests and troughs is in the longitudinal direction of the tunnel, it can control the deformation and stress of the surrounding rock in the longitudinal direction by virtue of its mechanical property of low compressive stiffness in the arrangement direction of its own crests and troughs. In a specific embodiment, each retaining layer 1 is formed by a plurality of corrugated retaining plates 3 connected to each other in the circumferential direction, and the specific number of corrugated retaining plates 3 in each retaining layer 1 is determined by the size and cross-sectional form of the tunnel cross section.

[0029] Based on the above structure, in the utility model, when the tunnel surrounding rock 4 produces radial deformation (or displacement) and stress, the buffer layer 2 densely filled between the surrounding rock and the retaining layer 1 can be used to relieve pressure and adapt, and when the tunnel surrounding rock 4 produces longitudinal deformation and stress, it can respond with the mechanical property of the corrugated retaining plate 3 of the retaining layer 1 having low compressive stiffness in the arrangement direction of its own wave crests and troughs. At the same time, when the tunnel surrounding rock 4 produces circumferential deformation and stress, since the connecting hole on the circumferential overlap portion of at least one of the adjacent corrugated retaining plates 3 of the retaining layer 1 is a strip-shaped elongated hole 10, the corrugated retaining plate 3 can produce relative displacement when subjected to circumferential pressure, thereby being able to adapt to the circumferential deformation and stress of the tunnel surrounding rock 4.

[0030] That is to say, in the present invention, it is possible to dynamically respond to the deformation and stress of the surrounding rock in three directions: radial, longitudinal and circumferential. This can improve the dynamic adaptability of the tunnel support structure, evenly distribute pressure, effectively exert the self-bearing capacity of the surrounding rock and shorten the construction period.

[0031] Moreover, compared with the prior art, what is more unexpected is that, while being able to dynamically respond to the deformation and stress of the surrounding rock from three directions at the same time, the overall structure of the support structure of the utility model with the corrugated retaining plate as the main body can still be kept relatively simple, which can greatly reduce the construction cost and construction period compared with the existing support structure that realizes multi-directional deformation response. In other words, the utility model achieves technical effects that cannot be achieved according to the prior art based on a simple overall structure.

[0032] In an embodiment of the utility model, the strip-shaped elongated hole 10 includes a positioning hole portion 10a and a U-shaped interference hole portion 10b that passes through the positioning hole portion 10a, and the annular connector 9 can extend from the positioning hole portion 10a to form a connection between the annular overlapping portions 8 of adjacent corrugated retaining plates 3; the strip-shaped elongated hole 10 and the annular connector 9 are jointly constructed so that when the corrugated retaining plate 3 is not subjected to annular pressure, the annular connector 9 is retained in the positioning hole portion 10a, and when the corrugated retaining plate 3 is subjected to annular pressure and exceeds the rated pressure, the annular connector 9 can enter the U-shaped interference hole portion 10b from the positioning hole portion 10a under the action of pressure and form an interference fit with the U-shaped interference hole portion 10b.

[0033] In a preferred embodiment, the strip-shaped elongated hole 10 is provided on the connecting portion of the corrugated retaining plate 3 located at the lower side in the circumferential direction among the adjacent corrugated retaining plates 3, and the connecting hole on the connecting portion of the corrugated retaining plate 3 located at the upper side in the circumferential direction among the adjacent corrugated retaining plates 3 is a conformal hole adapted to the shape of the circumferential connector 9. That is, among the two adjacent corrugated retaining plates 3 of the retaining layer 1, the circumferential overlap portion 8 of one of them is provided with the strip-shaped elongated hole 10, while the circumferential overlap portion 8 of the other one is only provided with a connecting hole conformal to the shape of the connector. In this case, the positioning hole portion 10a of the strip elongated hole 10 is also conformed to the shape of the connecting piece, and the connecting piece passes through the positioning hole portion 10a to form a connection with the connecting hole on another corrugated retaining plate 3, thereby connecting two adjacent corrugated retaining plates 3; at the same time, the radial dimension of the connecting piece is larger than the orifice size of the U-shaped interference hole portion 10b of the strip elongated hole 10, so that the connecting piece can be retained in the positioning hole portion 10a, and when annular pressure occurs, the connecting piece can be forced into the U-shaped interference hole portion 10b under the displacement of the corrugated retaining plate 3 under the action of pressure, and form an interference fit with the U-shaped interference hole portion 10b, thereby adapting to the annular deformation and stress of the tunnel surrounding rock 4.

[0034] In a particularly preferred embodiment, the annular connecting member 9 is a bolt, the positioning hole portion 10a of the strip-shaped elongated hole 10 on one annular overlap portion 8 is a circular hole, and the connecting hole on the other corresponding annular overlap portion 8 is a circular hole. The size of the annular U-shaped interference hole portion 10b along the annular direction is determined according to the longitudinal displacement value of the tunnel allowed in the specific project.

[0035] Based on the above-mentioned overall structure, the support structure of the utility model can still maintain self-stability when subjected to longitudinal, radial and circumferential deformation stresses, and will not collapse due to surrounding rock deformation and stress.

[0036] In the embodiment of the utility model, in the longitudinal direction of the tunnel, the corrugated retaining plates 3 of the adjacent retaining layers 1 are respectively provided with longitudinal overlaps, wherein the longitudinal overlap of the corrugated retaining plates 3 of one retaining layer 1 is provided with a longitudinally extending strip stretching hole, the strip stretching hole includes a longitudinal positioning hole portion and a longitudinal U-shaped interference hole portion, and the longitudinal overlap of the corrugated retaining plates 3 of the other retaining layer 1 is provided with a conformal hole adapted to the shape of the longitudinal connector; the strip stretching hole and the longitudinal connector are jointly constructed such that when the longitudinal pressure on the corrugated retaining plates 3 exceeds the deformation pressure that can be resisted by the crest and trough of the corrugated retaining plates 3, the longitudinal connector can enter the longitudinal U-shaped interference hole portion from the longitudinal positioning hole portion and form an interference fit with the longitudinal U-shaped interference hole portion. In a particularly preferred embodiment, the longitudinal connector is a bolt, the positioning hole portion of the strip stretching hole on one longitudinal overlap is a circular hole, and the other corresponding longitudinal overlap portion is provided with a connecting hole, which is a circular hole. The longitudinal size of the longitudinal U-shaped interference hole portion is determined according to the tunnel longitudinal displacement value allowed in the specific project.

[0037] Based on the setting of the strip expansion holes, when the longitudinal deformation and stress of the tunnel surrounding rock 4 exceed the compressive stiffness that the corrugated retaining plate 3 can withstand along the arrangement direction of its own wave crests and troughs, the strip expansion holes can participate in the adaptive work of the longitudinal deformation and stress of the tunnel surrounding rock 4, thereby further improving the adaptability of the support structure to the longitudinal deformation and stress of the tunnel surrounding rock 4.

[0038] Of course, those skilled in the art can also understand that, based on the setting of the strip extension holes, the connection structure of the longitudinally adjacent corrugated retaining plates 3 can also participate in the adaptive work of the longitudinal deformation and stress of the tunnel surrounding rock 4 simultaneously with the crests and troughs of the corrugated retaining plates 3 themselves, rather than working in steps.

[0039] In the embodiment of the present utility model, each corrugated retaining plate 3 of the retaining layer 1 is connected to the tunnel surrounding rock 4 through an anchor rod 5 .

[0040] In an embodiment of the utility model, a tunnel displacement deformation intelligent monitoring system is also provided for the support structure, which includes a pressure collection device, a pressure data transmission device and a background control device 15, wherein the pressure collection device includes a radial pressure collection device, and a radial pressure collection device is provided on the contact surface of the buffer layer 2 and the retaining layer 1, so as to collect data on the radial deformation pressure of the tunnel surrounding rock 4; wherein the pressure data transmission device can receive the pressure data collected by the radial pressure collection device and / or the longitudinal pressure collection device, and transmit it to the background control device 15; the background control device 15 can analyze and process the received radial pressure data, and can automatically give an early warning in combination with the stress and / or displacement values ​​in the pressure data.

[0041] In another embodiment, a longitudinal pressure acquisition device is also provided at a position adjacent to the retaining layer 1 in the longitudinal direction of the tunnel, so as to collect data on the longitudinal deformation pressure of the tunnel surrounding rock 4. The pressure data transmission device can also receive the pressure data collected by the longitudinal pressure acquisition device and transmit it to the background control device 15; the background control device 15 can analyze and process the received longitudinal pressure data, and can automatically warn in combination with the stress and / or displacement values ​​in the longitudinal pressure data.

[0042] In a specific embodiment, the pressure collection device can include a pressure box and a strain gauge 11. When the pressure box 12 and the strain gauge 11 are used as radial pressure collection devices, they are arranged on the contact surface between the corrugated retaining plate 3 and the buffer layer 2. In a particularly preferred embodiment, a plurality of pressure boxes 12 and strain gauges 11 are arranged on the vault, arch foot, arch waist, invert and side wall of each annular retaining layer 1. In a preferred embodiment, the pressure box 12 and the strain gauge 11 are arranged corresponding to the wave crest of the corrugated retaining plate 3.

[0043] The pressure data transmission device includes a signal acquisition module and a data collection module that transmits data through an electrical connection with the signal acquisition module, wherein the data collection module includes a storage 13 and a transmitter 14, which can transmit the collected pressure data to a background control device 15 by means of the transmitter 14.

[0044] The background control device 15 includes a central processing unit, which can be implemented by existing technology and will not be described in detail here. The background control device 15 monitors the data collected by the data collection module in real time, and performs three-level automatic warnings in combination with the stress and displacement limit values; the so-called three-level automatic warnings are mainly performed by monitoring the data collected by the data collection module by the background, and by writing relevant data processing programs, the collected data are comprehensively evaluated, and the part of the evaluation results that exceeds the set safety limit is divided into three levels, and the monitoring background performs three-level automatic alarms according to the specific evaluation results; the monitoring background and the data collection module remotely transmit data through wireless signals.

[0045] According to the new tunnel deformation-pressure adaptive support structure disclosed in the first aspect of the utility model, the buffer layer 2 is formed by filling the gap between the tunnel surrounding rock 4 and the retaining layer 1 with high elastic equal-size spheres 6; the radius of the high elastic equal-size spheres 6 is not greater than one tenth of the wave width of the corrugated retaining plate 3. The high elastic equal-size spheres 6 can realize the functions of pressure bearing, pressure transmission, and rolling pressure relief. The mechanical properties of the spheres, such as compression resistance and elastic modulus, should meet the specific engineering requirements. The surface of the spheres should be as smooth as possible to reduce the friction between the spheres and facilitate flow.

[0046] For the pressure regulation of the buffer layer 2, a pressure control device can be provided, which can be used to adjust the amount of spherical materials in a specific space in the buffer layer 2 to achieve deformation control of the surrounding rock-structure under a specific range of pressure.

[0047] The initial tunnel support structure of the utility model can be realized by means of the following construction method, which specifically includes the following steps:

[0048] Step S1, excavating a tunnel to form tunnel surrounding rock 4;

[0049] Step S2, facing the tunnel surrounding rock 4, sequentially connecting a plurality of corrugated retaining plates 3 in the tunnel ring direction to form a retaining layer 1, and allowing a gap space to exist between the retaining layer 1 and the tunnel surrounding rock 4;

[0050] Step S3, placing inflatable rubber pads at both ends of the annular retaining layer 1 in the longitudinal direction of the tunnel to seal the gap between the retaining layer 1 and the tunnel surrounding rock 4 at the ends of both sides;

[0051] Step S4, injecting high elastic equal-size spheres 6 into the gap space until the gap space is densely filled to form a buffer layer 2;

[0052] The above process is repeated in sequence along the longitudinal direction of the tunnel, and adjacent retaining layers 1 are overlapped and connected in the longitudinal direction of the tunnel.

[0053] In step S1, a suitable excavation method is selected according to geological conditions and design requirements. Here, the drilling and blasting method is used as an example. Before tunneling, measurement and layout are carried out to ensure the accuracy of the center line and horizontal position of the tunnel; at the same time, the drilling position, drilling depth and angle are determined to ensure uniform and effective blasting effect; after blasting, ventilation and smoke exhaust should be carried out in time and the cleaning of the tunnel slag should be completed.

[0054] After step S1 and before step S2, the method further includes the step of applying the anchor rod 5, specifically, removing dangerous rocks and ensuring that the excavation profile meets the requirements, and applying the anchor rod 5 in time after the excavation is completed.

[0055] In step S2, the corrugated retaining plate 3 prefabricated in the factory building outside the tunnel is transported to the construction site by a transport vehicle, and the pressure box 12 and the strain gauge 11 are installed at the crest of the corrugated retaining plate 3 on the contact surface between the corrugated retaining plate 3 and the buffer layer 2 as required, and then it is electrically connected to the data collection and transmission module; after the installation of the sensor and the data collection and transmission module, the installation position of the corrugated plate is determined and the single corrugated plate is assembled; during assembly, the single corrugated plate at the invert should be assembled first, followed by the side walls and the waist of the arch on both sides, and finally the single corrugated plate at the arch top is assembled to close the whole into a ring, thereby forming a retaining layer 1.

[0056] In step S3, inflatable rubber pads are arranged at both ends of the corrugated retaining plate 3 installed in a ring, and then inflated to completely close the gap between the corrugated retaining plate 3 and the surrounding rock.

[0057] In step S4, the pressure control device enters the field, connects the ball inlet with the reserved hole 7 on the corrugated retaining plate 3, and presses the balls in the ball storage bin into the gap between the corrugated plate and the surrounding rock through the hydraulic device until the gap is filled tightly.

[0058] After step S4, the base layer is cleaned, the base treatment agent is applied, and then the waterproof sheet is laid. After the construction is completed, the integrity and sealing of the waterproof layer are checked.

[0059] After step S4, the process also includes: preparing materials such as formwork, steel bars, concrete, etc., as well as construction equipment and personnel required for secondary lining construction. The secondary lining formwork trolley is in place, and longitudinal circumferential steel bars are installed according to design requirements, and then the formwork is installed. After the formwork is installed, concrete is poured and concrete curing is performed. After the concrete reaches a certain strength, the formwork is removed and a strength test is performed.

[0060] Then, repeat the above process to install the support structure at other locations until the construction of the support structure is completed.

[0061] In the disclosed construction method, in the longitudinal direction of the tunnel, after the construction of the corresponding buffer layer 2 of the next retaining layer 1 in the two adjacent retaining layers 1 is completed, the inflatable rubber pads that seal the ends at the adjacent positions of the two adjacent retaining layers 1 are completely deflated and withdrawn to form a common buffer layer 2 between the two adjacent retaining layers 1. The specific operation is: when filling the first ring retaining layer 1, the ends of the buffer layer 2 are inflated and sealed by the inflatable rubber pads, and then the buffer layer 2 is filled with spheres; after the second ring retaining layer 1 is constructed and closed into a ring, the ends of the second ring are inflated and sealed by the rubber pads, and then the spheres are filled. After the filling is completed, the rubber pads at the inflated and sealed ends at the joints of the first ring retaining layer 1 and the second ring retaining layer 1 are deflated and withdrawn to complete the construction of the second ring. Similarly, the sphere filling cycle construction of the buffer layer 2 is carried out.

[0062] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0063] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0064] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

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

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. A tunnel initial support structure, comprising a retaining layer arranged facing the tunnel surrounding rock and forming an annular shape in the tunnel, characterized in that: The retaining layer is constructed by connecting a plurality of corrugated retaining plates with continuous wave crests and wave troughs in the tunnel circumferential direction, and the corrugated retaining plates are arranged in such a way that the arrangement direction of their own wave crests and wave troughs is in the longitudinal direction of the tunnel, so as to adapt to the deformation and stress of the tunnel surrounding rock in the longitudinal direction; Furthermore, in each retaining layer, an annular overlap portion is respectively provided between two circumferentially adjacent corrugated retaining plates, and the annular overlap portions are connected to adjacent corrugated retaining plates by means of connecting holes and annular connecting pieces cooperating with the connecting holes. The connecting hole on the annular overlap portion of at least one of the adjacent corrugated retaining plates is an elongated strip hole, and is constructed together with the connecting piece to allow the corrugated retaining plate to produce relative displacement when subjected to annular pressure, so as to adapt to the deformation and stress of the tunnel surrounding rock in the annular direction.

2. The tunnel initial support structure according to claim 1, characterized in that: The strip-shaped elongated hole includes a positioning hole portion and a U-shaped interference hole portion that penetrates the positioning hole portion, and the annular connecting member can extend from the positioning hole portion to connect the annular overlapping portions of adjacent corrugated retaining plates; The strip-shaped elongated hole and the annular connecting piece are jointly constructed so that when the corrugated retaining plate is not subjected to annular pressure, the annular connecting piece is retained in the positioning hole portion; when the corrugated retaining plate is subjected to annular pressure and exceeds the rated pressure, the annular connecting piece can enter the U-shaped interference hole portion from the positioning hole portion under the action of pressure and form an interference fit with the U-shaped interference hole portion.

3. The tunnel initial support structure according to claim 2, characterized in that: The strip-shaped elongated hole is arranged on the connecting part of the corrugated retaining plate located below in the circumferential direction among the adjacent corrugated retaining plates, and the connecting hole on the connecting part of the corrugated retaining plate located above in the circumferential direction among the adjacent corrugated retaining plates is a conformal hole adapted to the shape of the circumferential connecting piece.

4. The tunnel initial support structure according to claim 3, characterized in that: Each corrugated retaining plate of the retaining layer is connected to the tunnel surrounding rock through an anchor rod.

5. The tunnel initial support structure according to claim 4, characterized in that: The retaining layers are arranged in plurality along the longitudinal direction of the tunnel, and there is a gap space between each retaining layer and the surrounding rock of the tunnel; It also includes a buffer layer, which is arranged between the retaining layer and the tunnel surrounding rock in a manner of filling the gap space to adapt to the radial deformation and stress of the tunnel surrounding rock.

6. The tunnel initial support structure according to claim 5, characterized in that: A radial pressure acquisition device is provided on the contact surface between the buffer layer and the retaining layer, so as to acquire data on the radial deformation pressure of the tunnel surrounding rock; And / or, in the longitudinal direction of the tunnel, a longitudinal pressure collection device is provided at a position adjacent to the retaining layer, so as to collect data on the longitudinal deformation pressure of the tunnel surrounding rock.

7. The tunnel initial support structure according to claim 6, characterized in that: It also includes a pressure data transmission device and a background control device, wherein the pressure data transmission device is capable of receiving the pressure data collected by the radial pressure collection device and / or the longitudinal pressure collection device and transmitting it to the background control device; The background control device can analyze and process the received pressure data, and can automatically warn in combination with the stress and / or displacement values ​​in the pressure data.

8. The tunnel initial support structure according to claim 7, characterized in that: The buffer layer is formed by filling the gap between the tunnel surrounding rock and the retaining layer with high elasticity spheres of equal particle size; The radius of the high-elastic equal-size spheres is no greater than one tenth of the wave width of the corrugated retaining plate.

9. The tunnel initial support structure according to claim 8, characterized in that: Inflatable rubber pads are arranged at both ends of each annular retaining layer in the longitudinal direction of the tunnel to block the gap between the retaining layer and the tunnel surrounding rock at the two end positions, so that high-elastic equal-size spheres can be injected into the gap space.

10. The tunnel initial support structure according to claim 9, characterized in that: in, In the longitudinal direction of the tunnel, after the corresponding buffer layer of the next retaining layer between two adjacent retaining layers is constructed, all the inflatable rubber pads sealing the ends at adjacent positions of the two adjacent retaining layers will be deflated and withdrawn to form a common buffer layer between the two adjacent retaining layers.

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