Construction method for variable-section tunnel

Abstract

A construction method for a variable-section tunnel, the construction method comprising: constructing a first section of a tunnel by means of a first tunnel-boring machine (S100); at an end position of the first section of the tunnel, providing a first receiving shaft for receiving the first tunnel-boring machine (S200); in the first receiving shaft, replacing the first tunnel-boring machine with a second tunnel-boring machine (S300), the first tunnel-boring machine and the second tunnel-boring machine having different construction section sizes; converting the first receiving shaft into a launch shaft of the second tunnel-boring machine (S400); constructing a second section of the tunnel by means of the second tunnel-boring machine (S500); and at an end position of the second section of the tunnel, providing a second receiving shaft for receiving the second tunnel-boring machine (S600).

Description

Variable cross-section tunnel construction method TECHNICAL FIELD

[0001] The present application relates to the technical field of underground construction, in particular to a variable cross-section tunnel construction method. BACKGROUND

[0002] In the construction of a subway interval tunnel and a station structure, the interval tunnel is often constructed by a shield method, and the station is often constructed by an open excavation method. However, the open excavation method has a greater impact on the surrounding environment, and if a non-excavation pipe-rodding method is used to construct the station, this problem can be avoided.

[0003] In the prior art, there is a shield-pipe-rodding integrated machine device, but the tunnel constructed by the device has the same cross-section size. However, the interval tunnel and the station end face of the subway have a large difference in size, so it is difficult to apply to the variable-diameter working condition. In addition, the existing shield-pipe-rodding integrated machine device essentially simultaneously assembles two systems to realize the switching of the two functions, but the device has a high cost, and in the process of jacking, the shield device in front needs to be jacked together, which increases the jacking force and is inconvenient to operate.

[0004] SUMMARY

[0005] The purpose of the present application is to provide a variable cross-section tunnel construction method which can realize the construction of different cross-sections of multiple tunnels.

[0006] WORK.

[0007] To solve the above technical problems, the present application provides the following technical solutions:

[0008] A variable cross-section tunnel construction method comprises:

[0009] constructing a first tunnel by a first tunneling machine;

[0010] setting a first receiving well for receiving the first tunneling machine at an end position of the first tunnel;

[0011] in the first receiving well, replacing the first tunneling machine with a second tunneling machine, the construction cross-section sizes of the first tunneling machine and the second tunneling machine being different;

[0012] converting the first receiving well into a starting well of the second tunneling machine;

[0013] constructing a second tunnel by the second tunneling machine;

[0014] setting a second receiving well for receiving the second tunneling machine at an end position of the second tunnel.

[0015] Preferably, the first tunneling machine and the second tunneling machine can be different types of tunneling machines or the same type of tunneling machine with different diameter cutters.

[0016] Preferably, the first tunneling machine is disassembled and replaced by the second tunneling machine, specifically including: replacing the cutter head of the first tunneling machine with a cutter head of a different diameter to disassemble and replace the first tunneling machine with the second tunneling machine, or disassembling the first tunneling machine to replace it with the second tunneling machine that can construct a different cross-section shape.

[0017] Preferably, the first tunneling machine is a shield machine, and the second tunneling machine is a pipe jacking machine; the first tunneling machine is disassembled and replaced by the second tunneling machine, specifically including: removing the outer shell of the front shield, the middle shield, and the tail shield of the shield machine, the segment erector, and the shield jacking device, retaining the cutter head, the main drive structure, and the screw conveyor of the shield machine, installing a front end housing at the front end of the shield machine and a rear end housing at the rear end of the shield machine, and expanding the cutter head of the shield machine to a large-diameter cutter head of the pipe jacking machine.

[0018] Preferably, the first receiving shaft is converted into a launching shaft of the second tunneling machine, specifically including: installing a pipe jacking reaction frame, a pipe jacking steel plate, and a pipe jacking jacking device in the first receiving shaft, and adjusting the receiving base and the guide rail structure in the first receiving shaft for the launching of the pipe jacking machine.

[0019] Preferably, the first tunneling machine is a pipe jacking machine, and the second tunneling machine is a shield machine; the first tunneling machine is disassembled and replaced by the second tunneling machine, specifically including: removing the outer shell of the pipe jacking machine, adjusting the pipe jacking cutter head to a small-diameter shield cutter head, and installing the outer shell of the front shield, the middle shield, and the tail shield of the shield machine, the segment erector, and the shield jacking device.

[0020] Preferably, the first receiving shaft is converted into a launching shaft of the second tunneling machine, specifically including: installing a shield reaction frame and a shield steel plate at the pipe jacking exit position, and adjusting the pipe jacking receiving base and the guide rail structure in the first receiving shaft for the launching of the shield machine.

[0021] Preferably, two tunnel lines including platforms are constructed, and the two platforms are expanded by using the underground excavation method to form a large cross-section platform.

[0022] Preferably, the two platforms are expanded by using the underground excavation method, specifically including:

[0023] Drilling and grouting to reinforce the part of the platform that needs to be expanded;

[0024] Mechanically breaking the pipe jacking segment of the part of the platform that needs to be expanded.

[0025] Preferably, after breaking the pipe jacking segment, the initial support is constructed by using the grid arch, shotcrete, connecting rib, and steel mesh, and the waterproof layer and secondary lining are constructed after the expansion.

[0026] Compared with the prior art, the technical scheme has the following advantages:

[0027] The variable cross-section tunnel construction method provided by the application comprises the following steps: constructing a first tunnel section by a first tunneling machine; setting a first receiving shaft for receiving the first tunneling machine at an end position of the first tunnel section; replacing the first tunneling machine with a second tunneling machine in the first receiving shaft, the first tunneling machine and the second tunneling machine having different construction cross-section sizes; converting the first receiving shaft into a launching shaft of the second tunneling machine; constructing a second tunnel section by the second tunneling machine; and setting a second receiving shaft for receiving the second tunneling machine at an end position of the second tunnel section. The same working shaft can be used for receiving and launching, thereby reducing construction cost and improving construction efficiency. In addition, the construction of different tunnel cross-sections can be realized, and compared with the traditional integrated switching construction equipment, the construction cost can be effectively reduced, and the construction method is simple and easy to operate. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0029] Fig. 1 is a flowchart of a variable cross-section tunnel construction method provided by a specific embodiment of the application;

[0030] Fig. 1 is a flowchart of a variable cross-section tunnel construction method provided by a specific embodiment of the application;

[0031] Fig. 2 is a schematic diagram of part of the construction of two subway interval tunnels and station platform tunnels;

[0032] Fig. 3 is a schematic diagram of the structure of a shield machine;

[0033] Fig. 4 is a schematic diagram of the structure of a pipe jacking machine;

[0034] Fig. 5 is a layout diagram of the converted pipe jacking machine and pipe jacking launching shaft;

[0035] Fig. 6 is a layout diagram of the converted shield machine and shield launching shaft;

[0036] Fig. 7 is a double-line station platform tunnel expansion construction profile diagram.

[0037] The reference signs are as follows: 1 is a shield cutter, 2 is a front shield, 3 is a middle shield, 4 is a shield tail, 5 is a screw conveyor, 6 is a shield jack, 7 is a segment erector, 8 is a main drive structure, 9 is a front end housing, 10 is a rear end housing, 11 is a pipe jacking pipe section, 12 is a pipe jacking jack, 13 is a top iron, 14 is a pipe jacking machine cutter, 15 is a thrust stop, 16 is a pipe jacking steel plate, 17 is a shield receiving base and guide rail structure, 18 is a shield receiving shaft, 19 is a pipe jacking reaction frame, 20 is a pipe jacking machine receiving base and guide rail structure, 21 is a negative ring segment, 22 is a shield reaction frame, and 23 is a shield steel plate. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned objectives, features and advantages of the present application more apparent and comprehensible, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0039] In the following description, specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a variety of ways beyond those described herein, which can be apparent to those skilled in the art without departing from the spirit and scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0040] One specific embodiment of the present application provides a variable cross-section tunnel construction method, as shown in FIG. 1, including the following steps:

[0041] S100: constructing a first section of tunnel by a first tunneling machine.

[0042] S200: setting a first receiving shaft for receiving the first tunneling machine at an end position of the first section of tunnel.

[0043] S300: replacing the first tunneling machine with a second tunneling machine in the first receiving shaft. The first tunneling machine and the second tunneling machine can be different types of tunneling machines, or the same type of tunneling machine with different diameter cutters. For example, the first tunneling machine can be a shield machine, and the second tunneling machine can be a pipe jacking machine, both of which have different diameters of cutters. In addition, the first tunneling machine can be a pipe jacking machine, and the second tunneling machine can be a shield machine. In addition, the first tunneling machine and the second tunneling machine can both be pipe jacking machines or shield machines. The construction methods of small-diameter shield to large-diameter pipe jacking, large-diameter pipe jacking to small-diameter shield, large-diameter shield to small-diameter pipe jacking, small-diameter pipe jacking to large-diameter shield, and even the conversion of shield-pipe jacking with the same cross-section size can be achieved. In addition, the first tunneling machine can be replaced by a second tunneling machine with a different cross-section shape, such as the conversion of circular shield-rectangular pipe jacking equipment with different sizes or the same size.

[0044] S400: convert the first receiving well into a launching well of the second tunneling machine. That is, the same working well can realize the functions of receiving and launching, so as to reduce the construction cost and improve the construction efficiency.

[0045] S500: construct the second section of the tunnel by the second tunneling machine.

[0046] S600: set a second receiving well for receiving the second tunneling machine at the end position of the second section of the tunnel. When the number of construction sections exceeds two, the above steps can be repeated to achieve the purpose of continuous construction.

[0047] The tunnel construction method provided by the embodiment of the application can be applied to integrated trenchless construction of a subway tunnel and a station platform, including construction of a subway interval shield tunnel to a station platform jacking tunnel and construction of a subway station platform jacking tunnel to an interval shield tunnel, as shown in FIG. 2, a cross-sectional size of the station platform jacking tunnel I is greater than that of the interval shield tunnel II.

[0048] I. Construction of a subway interval shield tunnel to a station platform jacking tunnel, including:

[0049] A shield receiving well 18 is set at the end position of the shield section a, and a structural floor of the receiving well is backfilled with C35 concrete to complete soil reinforcement of a receiving portal;

[0050] Shield posture rechecking measurement is performed, a shield machine receiving base and a guide rail structure 17 are arranged in the shield receiving well 18 according to the elevation of the receiving portal and the center elevation of the shield machine, to be used for receiving the shield machine, and elevation rechecking measurement is performed after installation is completed;

[0051] The shield receiving portal is chiseled out, and a receiving portal waterproof device is installed;

[0052] The interval tunnel is constructed by the shield machine;

[0053] After the shield section a construction is completed, the shield machine is received by the shield receiving well, and the shield machine is replaced by a jacking machine, as shown in FIGS. 3 and 4, specifically including: removing components of the shield machine, such as a front shield 2, a middle shield 3, a shield tail 4, a segment assembling machine 7, and shield jacks 12, which are not needed by the jacking machine, and retaining components of the shield machine, such as a cutter head 1, a main drive structure 8, and a screw conveyor 5, which are needed by the jacking machine;

[0054] The shield receiving base and the guide rail structure 17 are adjusted to be used for launching of the jacking machine, a front end shell 9 is installed at a front end of the shield machine, a rear end shell 10 is installed at a rear end of the shield machine, and the cutter head 1 of the shield machine is expanded into a large-diameter jacking machine cutter head 14;

[0055] The shield receiving well 18 is converted into a jacking launching well, as shown in FIG. 5, specifically including:

[0056] A pipe jacking reaction frame 19 is arranged at the exit of the tunneling machine, and a pipe steel plate 16 is arranged behind the pipe jacking reaction frame 19. The pipe steel plate 16 and the wall surface of the pipe launching shaft should be in close contact, otherwise high-strength concrete should be poured in the gap to ensure that the back wall is uniformly stressed during pipe jacking. The pipe jacking reaction frame 19 should not only have sufficient compressive strength, but also be adjusted in size according to actual needs to adapt to different sizes of shield receiving shafts.

[0057] The pipe jacking jack 12 is installed to provide forward driving force for pipe jacking. The hydraulic pump station of the pipe jacking machine uses the original hydraulic pump station of the tunneling machine. After installation, the whole machine is debugged, and after passing the qualification, the next process can be entered.

[0058] The hole sealing curtain rubber plate is installed, and the hole pre-buried bolt hole is cleaned, and the hole curtain rubber plate and the annular plate are installed.

[0059] After the pit dewatering construction, horizontal exploration holes are arranged within the hole range to check the quality of the reinforcement and the flow of water and sand. If the exploration hole is in good condition and no water and sand flow out, the pipe jacking launching hole can be broken and the hole can be drilled from top to bottom.

[0060] The thixotropic mud is injected and pressed to the outer wall of the pipe joint through the grouting hole reserved in the pipe joint, so that the outer wall of the pipe joint 11 forms a complete mud sleeve.

[0061] The thrust frame 15 is installed, the pipe joint 11 is hoisted, and the top iron 13 is installed. After the pipe jacking machine is debugged, the pipe jacking section b is started.

[0062] II. Construction of the metro station platform pipe jacking tunnel to the interval shield tunnel, including:

[0063] A pipe jacking receiving shaft is arranged at the end position of the pipe jacking section b.

[0064] In the pipe jacking receiving shaft, a pipe jacking machine receiving base and guide rail structure 20 are arranged for the pipe jacking machine to exit the hole.

[0065] The platform is constructed by the pipe jacking machine.

[0066] After the pipe jacking section b is constructed, the pipe jacking machine exits the hole and reaches the pipe jacking receiving shaft. The pipe jacking machine is replaced by a shield machine, as shown in FIGS. 3 and 4, which specifically includes: removing the outer shell of the pipe jacking machine, adjusting the pipe jacking cutter head 14 to a small-diameter shield cutter head 1, and installing the outer shells of the front shield 2, the middle shield 3, and the shield tail 4 of the shield machine, the segment erector 7, and the shield jacks 6.

[0067] The pipe jacking receiving shaft is converted into a shield launching shaft, and the pipe jacking machine receiving base and guide rail structure 20 are adjusted for the launching of the shield machine.

[0068] The shield launching hole stratum is reinforced.

[0069] The shield launching portal is excavated and the portal sealing device is installed;

[0070] The launching guide rail is installed in the shield launching portal, the shield counterforce frame 22 and the shield steel plate 23 are installed at the pipe jacking portal position B, and the specific structure is shown in Figure 6;

[0071] The negative ring segment 21 is installed, and the shield launching tunneling construction is prepared to start.

[0072] Both pipe jacking construction and shield construction are non-excavation construction technologies commonly used in infrastructure construction and have been widely used in the laying of various tunnels and underground pipelines. The shield machine is more flexible because the pushing device is in front, and can be constructed for a long distance with a certain curve radius, while the pipe jacking machine is just the opposite. The jacking force of the pipe jacking construction increases with the increase of the construction distance, and the jacking force of the shield construction does not change with the distance in theory, so the shield method is used for the construction of the section tunnel in the subway engineering construction.

[0073] By using the advantages of the two non-excavation technologies of shield construction and pipe jacking construction, the expansion construction of a small-size section tunnel to a large-section platform can be realized. After the construction of the previous section is completed, the existing receiving well structure is used to adjust and convert the equipment, and the existing receiving well is used as the launching well of the next section of engineering. Compared with the existing shield-pipe jacking integrated machine equipment, the overall cost is lower, and it is not necessary to consider the complex processes of changing the construction method, pipe joint and the connection treatment of the shield segment and the pipe joint during the underground construction, which is beneficial to the guarantee of engineering quality.

[0074] In an embodiment of the present application, the above construction method can be used to construct two tunnel lines including platforms, as shown in Figure 7. The two lines are preferably parallel lines, and can be constructed in sequence or simultaneously. After the construction is completed, the two platforms are expanded by the underground excavation method to form a large-section platform. The construction process includes the following steps:

[0075] The part III of the platform that needs to be expanded is drilled and grouted for reinforcement. According to the specific distance of the double lines and the quality of the surrounding soil, supporting measures such as advanced small pipe grouting and pipe curtain method are selected to ensure construction safety.

[0076] The pipe segment of the platform that needs to be expanded is mechanically broken. In order to avoid the influence of the mechanical breaking process on the stability of the segment structure, the breaking sequence is from top to bottom, and the concrete is broken and the steel bars are cut in zones.

[0077] After the pipe segment is broken, the initial support is constructed by using the grid arch, spraying concrete, connecting bars and steel mesh, and the waterproof layer and secondary lining are constructed after the expansion.

[0078] The embodiment forms the large-section station platform by supporting and excavating the soil between the two formed station tunnel, and the construction process can reduce the environmental and traffic influence, shorten the construction period and reduce the construction risk.

[0079] The tunnel construction method provided by the application can be applied to the underground tunnel engineering such as the intercity railway tunnel and the station structure, the variable-diameter underground water conveying tunnel, the Y-shaped tunnel and the like, in addition to the above-mentioned integrated trenchless construction applied to the subway tunnel construction and the station platform.

[0080] The receiving well is arranged at the position where the variable-diameter construction is needed;

[0081] After the previous shield construction is completed, the shield machine is received in the receiving well, and the receiving base and the guide rail structure of the shield machine are adjusted for the launching of the next tunnel shield machine;

[0082] The adjustment of the cutter head of different sizes and the expansion or reduction of the front shield, the middle shield and the tail shield of the shield machine in the receiving well is completed;

[0083] The counterforce frame structure suitable for the next shield machine construction is installed, the equipment is debugged, and the next different-size shield tunnel construction is prepared.

[0084] The above description of the disclosed embodiments enables those skilled in the art to carry out or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of variable cross-section tunnel construction, characterized by, The method comprises the following steps: constructing a first tunnel section by a first tunneling machine; setting a first receiving shaft for receiving the first tunneling machine at an end position of the first tunnel section; replacing the first tunneling machine with a second tunneling machine in the first receiving shaft, the first tunneling machine and the second tunneling machine having different cross-sectional sizes; converting the first receiving shaft into a launching shaft for the second tunneling machine; constructing a second tunnel section by the second tunneling machine; setting a second receiving shaft for receiving the second tunneling machine at an end position of the second tunnel section.

2. The variable-section tunneling method according to claim 1, characterized in that, The first tunneling machine and the second tunneling machine can be different types of tunneling machines or the same type of tunneling machine with different diameter cutters.

3. The variable-section tunneling method according to claim 1, wherein The replacing of the first tunneling machine with the second tunneling machine specifically comprises replacing the cutter of the first tunneling machine with a cutter having a different diameter to replace the first tunneling machine with the second tunneling machine, or replacing the first tunneling machine with the second tunneling machine capable of constructing a different cross-sectional shape.

4. The variable-section tunneling method of claim 1, wherein, The first tunneling machine is a shield machine, and the second tunneling machine is a pipe jacking machine; the replacing of the first tunneling machine with the second tunneling machine specifically comprises removing the outer shell of the front shield, the middle shield and the tail shield of the shield machine, the segment assembling machine and the shield jacking device, retaining the cutter, the main driving structure and the screw conveyor of the shield machine, installing the front end shell at the front end of the shield machine and installing the rear end shell at the rear end of the shield machine, and expanding the cutter of the shield machine into the cutter of the pipe jacking machine with a large diameter.

5. The variable-section tunneling method according to claim 4, characterized in that, The converting of the first receiving shaft into the launching shaft for the second tunneling machine specifically comprises setting the pipe jacking counterforce frame, the pipe jacking steel plate and the pipe jacking jacking device in the first receiving shaft, and adjusting the receiving base and the guide rail structure in the first receiving shaft for the launching of the pipe jacking machine.

6. The variable-section tunneling method of claim 1, wherein, The first tunneling machine is a pipe jacking machine, and the second tunneling machine is a shield machine; the replacing of the first tunneling machine with the second tunneling machine specifically comprises removing the outer shell of the pipe jacking machine, adjusting the cutter of the pipe jacking machine into the cutter of the shield machine with a small diameter, and installing the outer shell of the front shield, the middle shield and the tail shield of the shield machine, the segment assembling machine and the shield jacking device.

7. The variable-section tunneling method according to claim 6, characterized in that, The converting of the first receiving shaft into the launching shaft for the second tunneling machine specifically comprises installing the shield counterforce frame and the shield steel plate at the pipe jacking exit position, and adjusting the pipe jacking receiving base and the guide rail structure in the first receiving shaft for the launching of the shield machine.

8. A variable cross-section tunneling method according to any one of claims 1 to 7, characterized in that, The method for constructing two tunnel lines each comprising a platform adopts the underground excavation method to expand the two platforms to form a large cross-sectional platform.

9. The variable-section tunneling method according to claim 8, characterized in that, The method for expanding the two platforms by the underground excavation method specifically comprises the following steps: drilling and grouting to reinforce the part of the platform to be expanded; mechanically breaking the pipe jacking segment of the part of the platform to be expanded.

10. The variable-section tunneling method according to claim 9, wherein After the pipe jacking segment is broken, the initial support is constructed by using the grid arch, the sprayed concrete, the connecting rib and the steel mesh, and the waterproof layer and the secondary lining are constructed after the expansion.

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