Tunnel construction method

Abstract

The invention relates to the technical field of tunnel construction, in particular to a tunnel construction method, which comprises the following steps of: raising the vault elevation of an inclined shaft along the extending direction from a target tunnel face to a main tunnel when the inclined shaft is tunneled to a preset target tunnel face, and continuously performing excavation operation construction; a cover arch is constructed in the shed tunnel section, and a primary support of the upper step of the main tunnel is constructed in the cover arch; the main tunnel is excavated and constructed in the extending direction of the main tunnel, so that the arch crown of the inclined shaft can be lifted before the inclined shaft is excavated and constructed to the main tunnel during use, and the arch crown of the inclined shaft and the arch crown of the main tunnel are located at the same elevation; the risk of vault collapse caused by inconsistent elevation between the inclined shaft and the vault of the main tunnel during excavation operation construction of the main tunnel is avoided, and the safety of tunnel excavation operation construction is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel construction, and in particular to a tunnel construction method. Background Art

[0002] In the construction of extra-long tunnels, inclined shafts, cross tunnels and other methods are often used to increase the construction working surface. Domestic and foreign scholars have also conducted a lot of research on the top-lift construction of inclined shafts, cross tunnels and other methods, and there are many engineering examples. However, conventional schemes face many problems such as interference with large and small mileage construction, long top-lift construction, interference with the assembly of the secondary lining trolley, and the secondary lining safety step distance easily exceeding the standard after normal construction.

[0003] When excavating a long tunnel, an inclined shaft needs to be set up to increase the excavation working surface. However, in the prior art, when setting up the inclined shaft, the clearance elevation of the inclined shaft and the main tunnel cannot be the same. In the prior art, when the inclined shaft is excavated to the main tunnel, it is often excavated according to the clearance height of the inclined shaft, and then expanded after entering the main tunnel, and finally the excavation working surface of the main tunnel is formed. Although this method can complete the additional installation of the inclined shaft and the excavation of the main tunnel, there is a hidden danger of collapse of the arch of the main tunnel during the actual construction process. Summary of the invention

[0004] The main purpose of this application is to provide a tunnel construction method, which aims to solve the technical problem that when the related technology uses the inclined shaft to excavate the main tunnel, it is often excavated according to the clear height of the inclined shaft, and then expanded after entering the main tunnel, and finally forms the excavation working surface of the main tunnel. Although the method can complete the additional inclined shaft and the excavation of the main tunnel, there is a risk of collapse of the arch of the main tunnel during the actual construction process.

[0005] To achieve the above objectives, in a first aspect, the present application proposes a tunnel construction method, wherein the tunnel comprises a main tunnel and an inclined shaft intersecting the main tunnel;

[0006] The tunnel construction method comprises the following steps:

[0007] When the inclined shaft excavation construction reaches a preset target face, the crown elevation of the inclined shaft is raised along the extension direction from the target face to the main tunnel and the excavation construction is continued; wherein there is a target distance between the target face and the main tunnel;

[0008] When the excavation of the inclined shaft reaches the shed tunnel section, a casing arch is constructed in the shed tunnel section, and initial support for the upper step of the main tunnel is constructed in the casing arch;

[0009] The main tunnel is excavated along the extension direction of the main tunnel.

[0010] In one embodiment, when the inclined shaft excavation construction reaches a preset target tunnel face, the step of raising the crown elevation of the inclined shaft along the extension direction from the target tunnel face to the main tunnel and continuing the excavation operation construction includes:

[0011] When the inclined shaft is excavated to the preset target tunnel face, the arch top elevation of the inclined shaft is raised by a target slope along the extension direction from the target tunnel face to the main tunnel to form a current inclined arch;

[0012] When the crown elevation of the current inclined arch is raised to the crown elevation of the main tunnel, the arch foot position of the upper step of the main tunnel is constructed by flat slope excavation.

[0013] In one embodiment, when the arch crown elevation of the current inclined arch is raised to the arch crown elevation of the main tunnel, the step of constructing to the arch foot position of the upper step of the main tunnel by flat slope excavation operation includes:

[0014] When the top elevation of the current inclined arch is raised to the point where it connects with the main tunnel, excavation is continued at the connecting position using a shed tunnel method until entering the main tunnel; wherein a temporary support method is used in the shed tunnel for support construction;

[0015] When the arch crown elevation of the main tunnel is reached, the flat slope excavation operation is used to construct the arch foot position of the upper step of the main tunnel.

[0016] In one embodiment, when the current inclined arch crown elevation is raised to connect with the main tunnel, the step of continuing excavation construction at the connecting position by using a shed tunnel method until entering the main tunnel includes:

[0017] When the top elevation of the current inclined arch is raised to connect with the main tunnel, a reinforcement ring is applied at the connecting position of the current inclined arch and the main tunnel, and the lining operation is completed;

[0018] At the connecting position where the reinforcing ring is located after the lining work has been completed, the excavation construction is continued by using the shed tunnel method until entering the main tunnel.

[0019] In one embodiment, when the top elevation of the current inclined arch is raised to connect with the main tunnel, a reinforcement ring is applied at the connecting position of the current inclined arch and the main tunnel, and the lining operation is completed, including:

[0020] When the top elevation of the current inclined arch is raised to connect with the main tunnel, a reinforcement ring is applied at the connecting position of the current inclined arch and the main tunnel;

[0021] A casing arch is constructed inside the reinforcement ring, and the casing arch and temporary support are simultaneously constructed on both sides of the reinforcement ring facing the main tunnel to complete the lining operation of the inclined shaft.

[0022] In one embodiment, the step of excavating the main tunnel along the extension direction of the main tunnel includes:

[0023] Along the extension direction of the main tunnel, the sleeve arch and temporary support are simultaneously applied on both sides of the main tunnel on one side of the reinforcement ring;

[0024] The temporary support on the corresponding side is removed, and a corresponding excavation method is selected according to the preset survey data of the main tunnel to carry out excavation construction on the main tunnel of the tunnel.

[0025] In one embodiment, the step of removing the temporary support on the corresponding side and selecting a corresponding excavation method to excavate the tunnel main tunnel according to preset survey data of the main tunnel includes:

[0026] The temporary support on the corresponding side is removed, and under the protection of the sleeve arch, the initial support of the main tunnel is implemented according to the preset survey data of the main tunnel, and the upper arc-shaped pilot pit of the main tunnel is excavated to form a section to be excavated below the arc-shaped pilot pit;

[0027] According to the preset survey data, the corresponding excavation method is selected to carry out excavation construction on the main tunnel.

[0028] In one embodiment, the step of removing the temporary support on the corresponding side, and performing initial support of the main tunnel and excavating the upper arc-shaped pilot pit of the main tunnel according to the preset survey data of the main tunnel under the protection of the casing arch to form a section to be excavated below the arc-shaped pilot pit includes:

[0029] The temporary support on the corresponding side is removed, and under the protection of the sleeve arch, the initial support of the main tunnel is implemented according to the preset survey data of the main tunnel, and the upper arc-shaped pilot pit of the main tunnel is excavated to a preset length to form the current heading face;

[0030] The current tunnel face is sprayed with concrete to close the current tunnel face, so as to form a section to be excavated below the arc-shaped pilot pit.

[0031] In one embodiment, before the step of removing the temporary support on the corresponding side and selecting a corresponding excavation method according to the preset survey data of the main tunnel to excavate the main tunnel of the tunnel, the method further includes:

[0032] The temporary support on the other side is removed, and a corresponding excavation method is selected according to the preset survey data of the main tunnel to carry out excavation construction on the main tunnel of the tunnel.

[0033] In one embodiment, after the step of removing the temporary support on the corresponding side and selecting a corresponding excavation method according to the preset survey data of the main tunnel to excavate the main tunnel of the tunnel, the method further includes:

[0034] After the preset distance is constructed on both sides of the reinforcement ring, excavation work is carried out on both sides simultaneously until the main tunnel is connected.

[0035] One or more technical solutions proposed in this application have at least the following technical effects:

[0036] The technical solution of the present application is to raise the elevation of the arch of the inclined shaft along the extension direction from the target face to the main tunnel when the inclined shaft excavation construction reaches the preset target face and continue the excavation operation; when the inclined shaft excavation construction reaches the shed tunnel section, a casing arch is constructed in the shed tunnel section, and initial support for the upper step of the main tunnel is constructed in the casing arch; the main tunnel is excavated along the extension direction of the main tunnel, so that the arch of the inclined shaft can be raised before the inclined shaft excavation construction reaches the main tunnel, and the arch of the inclined shaft and the arch of the main tunnel are located at the same elevation, thereby avoiding the risk of arch collapse during excavation construction of the main tunnel due to inconsistent elevations between the arches of the inclined shaft and the main tunnel, thereby improving the safety of tunnel excavation construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0039] Figure 1 A flow chart provided for the first embodiment of the tunnel construction method of the present application;

[0040] Figure 2 for Figure 1 Flow chart of step S100 in the example;

[0041] Figure 3 for Figure 2 Flow chart of step S120 in the example;

[0042] Figure 4 for Figure 1 Flow chart of step S300 in the example;

[0043] Figure 5 for Figure 4 Flowchart of step S320 illustrated in FIG.

[0044] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0047] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0048] Based on this, see Figures 1 to 5 , the tunnel construction method, the tunnel comprises a main tunnel and an inclined shaft intersecting with the main tunnel;

[0049] The tunnel construction method comprises the following steps:

[0050] S100, when the inclined shaft excavation construction reaches a preset target face, the crown elevation of the inclined shaft is raised along the extension direction from the target face to the main tunnel and the excavation construction is continued; wherein there is a target distance between the target face and the main tunnel;

[0051] S200, when the excavation operation of the inclined shaft reaches the shed tunnel section, a casing arch is constructed in the shed tunnel section, and an initial support for the upper step of the main tunnel is constructed in the casing arch;

[0052] S300, excavating the main tunnel along the extension direction of the main tunnel.

[0053] In this embodiment, the specific implementation process is as follows: when the construction inclined shaft approaches the intersection mileage of the main tunnel, the construction arch elevation is gradually raised and the steel frame is extended. The arch elevation slope is controlled within 30%. After the construction inclined shaft excavates the main tunnel excavation contour line, a reinforcement ring is applied at the intersection, and the lining of the intersection section of the construction inclined shaft is applied in time. At the intersection of the construction inclined shaft and the main tunnel, a shed tunnel is used to enter the main tunnel. After the shed tunnel climbs up obliquely to the arch of the main tunnel, it is excavated forward with a flat slope to the arch foot position of the upper step on the outside of the main tunnel. A sleeve arch is set in the shed tunnel, and the initial support of the upper step of the main tunnel is applied in the sleeve arch. Along the direction of the tunnel main tunnel, the temporary support on one side of the shed is removed, and according to the geological conditions, a reasonable excavation method and support parameters are selected to apply the sleeve arch. Under the protection of the sleeve arch, the initial support of the main tunnel is applied and the upper arc guide pit is excavated. After excavating 10m forward, spray concrete to close the face and suspend excavation in this direction. Turn around and remove the temporary support on the other side of the scaffolding. According to the geological conditions, select a reasonable excavation method and support parameters, build a sleeve arch, and under the protection of the sleeve arch, build the initial support of the main tunnel and excavate the upper arc guide pit. After excavating 10m forward, spray concrete to seal the face and suspend excavation in this direction. When the space is sufficient, the main tunnel is constructed on both sides at the same time to reach the bottom. After the main tunnel reaches the bottom, the main tunnel invert arch construction is carried out in time so that the initial support and the invert arch can be formed into a ring as soon as possible to ensure construction safety.

[0054] In this embodiment, when the inclined shaft excavation construction reaches the preset target heading, the arch crown elevation of the inclined shaft is raised along the extension direction from the target heading to the main tunnel and the excavation operation is continued; when the inclined shaft excavation operation reaches the shed tunnel section, a casing arch is constructed in the shed tunnel section, and initial support for the upper step of the main tunnel is constructed in the casing arch; the main tunnel is excavated along the extension direction of the main tunnel, so that when the present invention is used, the arch crown of the inclined shaft can be raised before the inclined shaft excavation construction reaches the main tunnel, and the arch crown of the inclined shaft and the arch crown of the main tunnel are located at the same elevation, thereby avoiding the risk of arch crown collapse during excavation of the main tunnel due to inconsistent elevations between the arch crowns of the inclined shaft and the main tunnel, thereby improving the safety of tunnel excavation operation.

[0055] In one embodiment, step S100 includes:

[0056] S110, when the inclined shaft excavation construction reaches the preset target tunnel face, the arch top elevation of the inclined shaft is raised by a target slope along the extension direction from the target tunnel face to the main tunnel to form a current inclined arch;

[0057] S120. When the crown elevation of the current inclined arch is raised to the crown elevation of the main tunnel, the arch foot position of the upper step of the main tunnel is constructed by flat slope excavation.

[0058] In one embodiment, step S120 includes:

[0059] S121, when the top elevation of the current inclined arch is raised to connect with the main tunnel, excavation construction is continued at the connecting position by using a shed tunnel method until entering the main tunnel; wherein a temporary support method is used in the shed tunnel for support construction;

[0060] S122. When the arch crown elevation of the main tunnel is reached, the flat slope excavation operation is used to construct the arch foot position of the upper step of the main tunnel.

[0061] In one embodiment, step S121 includes:

[0062] S123, when the top elevation of the current inclined arch is raised to connect with the main tunnel, a reinforcement ring is applied at the connecting position of the current inclined arch and the main tunnel, and the lining operation is completed;

[0063] S124. Continue excavation at the connecting position where the reinforcing ring is located after the lining work has been completed by using a shed tunnel method until entering the main tunnel.

[0064] In one embodiment, step S123 includes:

[0065] S125, when the top elevation of the current inclined arch is raised to connect with the main tunnel, a reinforcement ring is applied at the connecting position of the current inclined arch and the main tunnel;

[0066] S126. Construct a casing arch inside the reinforcement ring, and construct the casing arch and temporary support simultaneously on both sides of the reinforcement ring facing the main tunnel to complete the lining operation of the inclined shaft.

[0067] In one embodiment, step S300 includes:

[0068] S310, along the extension direction of the main tunnel, simultaneously apply the sleeve arch and temporary support on both sides of the main tunnel on one side of the reinforcement ring;

[0069] S320, dismantling the temporary support on the corresponding side, and selecting a corresponding excavation method according to the preset survey data of the main tunnel to perform excavation construction on the main tunnel of the tunnel.

[0070] In one embodiment, step S320 includes:

[0071] S321, removing the temporary support on the corresponding side, and under the protection of the sleeve arch, carrying out the initial support of the main tunnel and excavating the upper arc-shaped pilot pit of the main tunnel according to the preset survey data of the main tunnel, so as to form a section to be excavated below the arc-shaped pilot pit;

[0072] S322. According to the preset survey data, select the corresponding excavation method to perform excavation construction on the main tunnel.

[0073] In one embodiment, step S321 includes:

[0074] S323, removing the temporary support on the corresponding side, and under the protection of the sleeve arch, carrying out the initial support of the main tunnel according to the preset survey data of the main tunnel and excavating the upper arc-shaped pilot pit of the main tunnel to a preset length to form the current heading face;

[0075] S324, performing a shotcrete operation on the current tunnel face to close the current tunnel face, so as to form a section to be excavated below the arc-shaped pilot pit.

[0076] In one embodiment, before step S320, the method further includes:

[0077] S330, removing the temporary support on the other side, and selecting a corresponding excavation method according to the preset survey data of the main tunnel to perform excavation construction on the main tunnel of the tunnel.

[0078] In one embodiment, after step S320, the method further includes:

[0079] S340, after constructing the preset distance on both sides of the reinforcement ring, excavation work is carried out on both sides simultaneously until the main tunnel is connected.

[0080] In some exemplary embodiments, the longitudinal climbing guide tunnel method can also be used to expand the inclined shaft. Specifically, after the construction inclined shaft is excavated to the main tunnel excavation contour line, a reinforcement ring is applied at the intersection, and the secondary lining of the intersection section of the construction inclined shaft is applied in time. According to the determined curve radius, the center line of the climbing guide tunnel is measured and set, and the climbing guide tunnel is excavated obliquely upward along one side of the tunnel to the main tunnel arch. The section of the climbing guide tunnel is adjusted according to the surrounding rock conditions. After the arch of the climbing guide tunnel and the arch of the main tunnel are at the same elevation, the main tunnel is directly excavated in the guide tunnel. After the main tunnel at one end is constructed for 10m, the face is closed by spraying concrete. Turn around and select the construction plan according to the geological conditions of the main tunnel for excavation. During the excavation process, the steel frame of the climbing guide pit that has an impact is removed. During the construction, after excavating a certain distance as needed, the excavation in this direction is suspended, and the face is closed by spraying concrete, and then excavation and support are carried out according to the designed excavation direction according to the normal process. The main tunnel is excavated according to the construction method of the corresponding surrounding rock grade.

[0081] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A tunnel construction method, characterized in that: The tunnel comprises a main tunnel and an inclined shaft intersecting with the main tunnel; The tunnel construction method comprises the following steps: When the inclined shaft excavation construction reaches a preset target face, the crown elevation of the inclined shaft is raised along the extension direction from the target face to the main tunnel and the excavation construction is continued; wherein there is a target distance between the target face and the main tunnel; When the excavation of the inclined shaft reaches the shed tunnel section, a casing arch is constructed in the shed tunnel section, and initial support for the upper step of the main tunnel is constructed in the casing arch; The main tunnel is excavated along the extension direction of the main tunnel.

2. The tunnel construction method according to claim 1, characterized in that: The step of raising the crown elevation of the inclined shaft along the extension direction from the target tunnel face to the main tunnel and continuing the excavation operation when the inclined shaft excavation construction reaches a preset target tunnel face comprises: When the inclined shaft is excavated to the preset target tunnel face, the arch top elevation of the inclined shaft is raised by a target slope along the extension direction from the target tunnel face to the main tunnel to form a current inclined arch; When the crown elevation of the current inclined arch is raised to the crown elevation of the main tunnel, the arch foot position of the upper step of the main tunnel is constructed by flat slope excavation.

3. The tunnel construction method according to claim 2, characterized in that: The step of constructing to the arch foot position of the upper step of the main tunnel by flat slope excavation operation when the arch crown elevation of the current inclined arch is raised to the arch crown elevation of the main tunnel comprises: When the top elevation of the current inclined arch is raised to the point where it connects with the main tunnel, excavation is continued at the connecting position using a shed tunnel method until entering the main tunnel; wherein a temporary support method is used in the shed tunnel for support construction; When the arch crown elevation of the main tunnel is reached, the flat slope excavation operation is used to construct the arch foot position of the upper step of the main tunnel.

4. The tunnel construction method according to claim 3, characterized in that: When the elevation of the current inclined arch crown is raised to connect with the main tunnel, the step of continuing excavation construction at the connecting position by using a shed tunnel method until entering the main tunnel includes: When the top elevation of the current inclined arch is raised to connect with the main tunnel, a reinforcement ring is applied at the connecting position of the current inclined arch and the main tunnel, and the lining operation is completed; At the connecting position where the reinforcing ring is located after the lining work has been completed, the excavation construction is continued by using the shed tunnel method until entering the main tunnel.

5. The tunnel construction method according to any one of claims 1 to 4, characterized in that: When the top elevation of the current inclined arch is raised to connect with the main tunnel, a reinforcement ring is applied at the connecting position of the current inclined arch and the main tunnel, and the lining operation is completed, including: When the top elevation of the current inclined arch is raised to connect with the main tunnel, a reinforcement ring is applied at the connecting position of the current inclined arch and the main tunnel; A casing arch is constructed inside the reinforcement ring, and the casing arch and temporary support are simultaneously constructed on both sides of the reinforcement ring facing the main tunnel to complete the lining operation of the inclined shaft.

6. The tunnel construction method according to claim 5, characterized in that: The step of excavating the main tunnel along the extension direction of the main tunnel comprises: Along the extension direction of the main tunnel, the sleeve arch and temporary support are simultaneously applied on both sides of the main tunnel on one side of the reinforcement ring; The temporary support on the corresponding side is removed, and a corresponding excavation method is selected according to the preset survey data of the main tunnel to carry out excavation construction on the main tunnel of the tunnel.

7. The tunnel construction method according to claim 6, characterized in that: The step of removing the temporary support on the corresponding side and selecting a corresponding excavation method to excavate the tunnel main tunnel according to the preset survey data of the main tunnel includes: The temporary support on the corresponding side is removed, and under the protection of the sleeve arch, the initial support of the main tunnel is implemented according to the preset survey data of the main tunnel, and the upper arc-shaped pilot pit of the main tunnel is excavated to form a section to be excavated below the arc-shaped pilot pit; According to the preset survey data, the corresponding excavation method is selected to carry out excavation construction on the main tunnel.

8. The tunnel construction method according to claim 7, characterized in that: The step of removing the temporary support on the corresponding side, and carrying out the initial support of the main tunnel and excavating the upper arc-shaped pilot pit of the main tunnel according to the preset survey data of the main tunnel under the protection of the sleeve arch, so as to form a section to be excavated below the arc-shaped pilot pit, includes: The temporary support on the corresponding side is removed, and under the protection of the sleeve arch, the initial support of the main tunnel is implemented according to the preset survey data of the main tunnel, and the upper arc-shaped pilot pit of the main tunnel is excavated to a preset length to form the current heading face; The current tunnel face is sprayed with concrete to close the current tunnel face, so as to form a section to be excavated below the arc-shaped pilot pit.

9. The tunnel construction method according to claim 6, characterized in that: Before the step of removing the temporary support on the corresponding side and selecting a corresponding excavation method according to the preset survey data of the main tunnel to excavate the main tunnel of the tunnel, the method further includes: The temporary support on the other side is removed, and a corresponding excavation method is selected according to the preset survey data of the main tunnel to carry out excavation construction on the main tunnel of the tunnel.

10. The tunnel construction method according to claim 6, characterized in that: After the step of removing the temporary support on the corresponding side and selecting a corresponding excavation method according to the preset survey data of the main tunnel to excavate the main tunnel of the tunnel, the method further includes: After the preset distance is constructed on both sides of the reinforcement ring, excavation work is carried out on both sides simultaneously until the main tunnel is connected.

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