A safe and fast construction structure for a rock mass tunnel and a construction method thereof

Abstract

The application discloses a kind of broken rock mass tunnel safe and fast construction structure and its construction method, including several blocks of assembled steel corrugated plate and steel arch frame;Steel corrugated plate is set in the arch of tunnel, and steel arch frame is installed in the side wall and inverted arch position in tunnel;Steel corrugated plate and steel arch frame are fixedly connected by connecting assembly;The area where steel arch frame is located is provided with steel mesh and longitudinal connecting steel, and the area is sprayed with concrete operation;Steel corrugated plate and steel arch frame are fixedly connected with full-ring steel arch frame.The application replaces the traditional steel arch frame structure by setting steel corrugated plate in arch, and effectively combines steel corrugated plate and steel arch frame to form a combined structure, which can avoid the safety damage of arch drop block to installers during installation, and can fully exert the advantages of the two structures.

Description

Technical Field

[0001] This invention belongs to the technical field of tunnel support, specifically relating to a safe and rapid construction structure and construction method for tunnels in fractured rock mass. Background Technology

[0002] As underground engineering technology develops towards safety and speed, the construction process of the initial support steel frame for tunnels has become a high-risk procedure in current construction.

[0003] The initial installation of the support steel arch frame currently has the following shortcomings:

[0004] 1) Steel frame installation is generally done manually. During the arch frame installation process, there is a risk of rockfall in the surrounding rock of the arch, which poses a risk of injury and death to workers.

[0005] 2) After the steel arch frame is installed, shotcrete construction is carried out. The backfilling volume of the arch is large, the construction loss is large, the construction time is long, and the construction speed is slowed down.

[0006] 3) Arch frame installation machines can speed up installation, but they are not very adaptable to complex geological sections and are expensive. Summary of the Invention

[0007] The purpose of this invention is to address the aforementioned shortcomings in the prior art by providing a safe and rapid construction structure and construction method for tunnels in fractured rock masses, thereby solving the problems of safety risks, slow construction speed, and high cost associated with existing initial support steel frames.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] Firstly, a safe and rapid construction structure for tunnels in fractured rock masses includes several assembled corrugated steel plates and steel arch frames; the corrugated steel plates are installed in the arch of the tunnel, and the steel arch frames are installed in the sidewalls and invert sections of the tunnel.

[0010] The corrugated steel plate and the steel arch frame are fixedly connected by connecting components; a steel mesh and longitudinal connecting steel bars are set in the area where the steel arch frame is located, and shotcrete is applied to the area; both the corrugated steel plate and the steel arch frame are fixedly connected to the full-ring steel arch frame.

[0011] Furthermore, the steel arch frame is a shaped steel arch frame, which is quickly fixed to the surrounding rock by locking foot anchors or anchor pipes.

[0012] Furthermore, several anchor bolt holes are pre-drilled in the corrugated steel sheet, and the corrugated steel sheet is fixed to the surrounding rock by installing anchor bolts in the anchor bolt holes.

[0013] Furthermore, the connecting assembly includes a connecting plate and a flange; the flange is welded to the end of the corrugated steel plate, and the connecting plate is welded to the end of the steel arch frame; the connecting plate and the flange are fixedly connected by bolts.

[0014] Furthermore, the full-ring steel arch frame and the steel arch frame are sealed by welding, and concrete is sprayed onto the surface of the steel arch frame.

[0015] Furthermore, the full-ring steel arch frame is welded to the corrugated steel plate, and the gap between the corrugated steel plate and the surrounding rock is filled by grouting or pouring self-compacting concrete behind the corrugated steel plate.

[0016] Secondly, a construction method for a safe and rapid construction structure for tunnels in fractured rock masses includes the following steps:

[0017] S1. Excavate the tunnel according to the designed cross-sectional shape;

[0018] S2. Design parameters for corrugated steel plates and steel arch frames;

[0019] S3. On-site splicing of corrugated steel plates into a complete ring section, followed by lifting onto a platform using a forklift or steel frame installation machine, and supporting the corrugated steel plates with four lifting jacks.

[0020] S4. Install the steel arch frame on the side wall and fix the steel arch frame with locking anchor rods or anchor pipes;

[0021] S5. During installation on the sidewall, anchor bolts are installed under the protection of corrugated steel plates, and drilling and anchor bolt installation are carried out through the pre-drilled anchor bolt holes in the corrugated steel plates.

[0022] S6. Drive the lifting jack to lift the corrugated steel plate to the design height, connect the steel frame and the corrugated steel plate through the connecting components, and weld the anchor rod and the corrugated steel plate to fix them.

[0023] S7. Install steel mesh and longitudinal connecting steel bars in the area supported by steel arch frame, and carry out shotcrete operation in the area until the design thickness of shotcrete is reached.

[0024] S8. Repeat steps S3 to S7 until the longitudinal design length of the assembled corrugated steel sheet is reached.

[0025] S9. Construct a full-ring steel frame, and weld and seal the full-ring steel arch frame to the steel arch frame and the steel corrugated plate respectively;

[0026] S10. Grouting or pouring self-compacting concrete is carried out through the grouting holes or pouring ports reserved on the corrugated steel plate to fill the space between the corrugated steel plate and the surrounding rock.

[0027] Furthermore, the parameters of the corrugated steel sheet include the span, waveform, thickness, circumferential and longitudinal width; the parameters of the steel arch frame include the model of the steel arch frame and the longitudinal spacing.

[0028] Furthermore, the grouting in step S10 is cement grout or polyurethane polymer foam filler.

[0029] Furthermore, when in strata prone to rockbursts, a layer of foam or rubber is adhered to the upper surface of the corrugated steel sheet.

[0030] The safe and rapid construction structure and construction method for tunnels in fractured rock masses provided by this invention have the following beneficial effects:

[0031] This invention replaces the traditional steel arch frame structure with a corrugated steel plate in the arch section, and effectively combines the corrugated steel plate and the steel arch frame to form a combined structure. This can avoid the safety injury to the installation workers caused by the falling of the arch section during the installation process, and can also give full play to the advantages of the two structures.

[0032] The corrugated steel sheet of this invention is prefabricated in the factory and assembled on site, forming a complete structure in one go. This ensures the quality of the structure and facilitates on-site construction, improving construction efficiency. Furthermore, the corrugated steel sheet is a flexible structure that can effectively resist the impact of rockbursts, playing a significant role in safe construction in areas with severe rockbursts.

[0033] The steel corrugated plate of this invention does not require shotcrete support for the arch section, which effectively reduces the construction time of shotcrete and greatly improves work efficiency. Furthermore, the steel corrugated plate can effectively form a joint support structure with anchor bolts, which is of positive significance for the safety of tunnel structures in complex geological sections. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the overall tunnel combination structure of the present invention.

[0035] Figure 2 This is a schematic diagram of the connection structure between the tunnel corrugated steel plate and the steel arch frame of the present invention.

[0036] Figure 3 This is a schematic diagram of the tunnel construction method of the present invention.

[0037] Among them, 1. Corrugated steel plate; 2. Excavation face of surrounding rock; 3. Filling above the corrugated steel plate; 4. Steel arch frame; 5. Shotcrete; 6. Connecting components; 7. Steel frame connectors; 8. Platform; 9. Lifting jack; 10. Anchor pipe; 11. Anchor rod; 31. Flange; 32. Connecting cross plate; 33. Bolt. Detailed Implementation

[0038] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0039] Example 1

[0040] refer to Figure 1 This embodiment provides a safe and rapid construction structure for tunnels in fractured rock masses. This embodiment utilizes a combination of corrugated steel plates 1 and steel arch frames 4 to ensure the safety of installation workers during construction. Specifically, it includes:

[0041] Several corrugated steel plates 1 and steel arch frames 4 are assembled together. The corrugated steel plates 1 and steel arch frames 4 are fixedly connected by connecting components 6 to form a combined support structure for rapid support.

[0042] refer to Figure 2 The connecting assembly 6 includes a connecting plate 32 and a flange 31; the flange 31 is welded to the end of the corrugated steel plate 1, and the connecting plate 32 is welded to the end of the steel arch frame 4; the connecting plate 32 and the flange 31 are fixedly connected by multiple high-strength bolts 33.

[0043] The corrugated steel plate 1 is installed in the arch of the tunnel. The corrugated steel plate 1 includes a prefabricated corrugated steel plate 1 in the factory. The corrugated steel plate 1 is formed on the construction site by splicing the prefabricated steel plate 1. The longitudinal width of the corrugated steel plate 1 is determined according to the design value. In this embodiment, it is preferably 1m to 1.5m. The longitudinal corrugated steel plates 1 are connected by overlapping or inner flange 31.

[0044] refer to Figure 3 In this embodiment, the longitudinal length of the corrugated steel plate 1 during a single construction is determined by the length of a single excavation. A single, two, or three corrugated steel plates 1 are longitudinally connected to form a tunneling construction unit. After being assembled inside the tunnel, they are lifted onto the platform 8 by a loader or a steel arch frame 4 installation machine. The platform 8 is then fixed by four lifting jacks 9 installed on it. Workers construct and position the side wall steel arch frame 4 under the protection of the corrugated steel plate 1. After the steel arch frame 4 is installed in place, the lifting jacks 9 lift the corrugated steel plate 1 into place, and the connection between the corrugated steel plate 1 and the steel arch frame 4 is performed.

[0045] In this embodiment, anchor bolt 11 holes are pre-drilled in the corrugated steel plate 1. After the combined support structure is constructed, the anchor bolt 11 is installed, and the corrugated steel plate 1 and the anchor bolt 11 are effectively connected. That is, the corrugated steel plate 1 is fixed to the surrounding rock by installing the anchor bolt 11 in the anchor bolt 11 hole.

[0046] After the corrugated steel plate 1 and the steel arch frame 4 are connected and fixed, the steel arch frame 4 construction area is equipped with steel mesh and shotcrete 5 to quickly seal the surrounding rock excavation face 2.

[0047] The length of a single longitudinal section of the assembled corrugated steel plate 1 is generally set to 3 excavations or not exceeding 10m. After the construction of a longitudinal section of the assembled corrugated steel plate 1 is completed, a full-ring steel arch frame 4 is set up. The full-ring steel arch frame 4 and the steel arch frame 4 are sealed by welding, and concrete 5 is sprayed on the surface of the steel arch frame 4. The full-ring steel arch frame 4 is welded to the corrugated steel plate 1.

[0048] After the entire area around the corrugated steel plate 1 in this longitudinal section is sealed with shotcrete, grout or self-compacting concrete is injected through the pre-reserved grouting holes or concrete pouring ports to fill the gaps between the assembled corrugated steel plate 1 and the surrounding rock, ensuring a tight fit. Figure 1 Filler 3 above the corrugated steel plate.

[0049] The steel arch frame 4 is installed on the sidewall and invert arch of the tunnel and is quickly fixed to the surrounding rock by anchor bolts 11 or anchor pipes 10. In this embodiment, the steel arch frame 4 is a steel section steel arch frame 4, preferably I-beam or H-beam. The longitudinal spacing of the steel arch frame 4 can be adjusted according to the surrounding rock grade. Two steel arch frames 4 can be connected by steel frame connectors 7. The steel frame connectors 7 can be horizontal plates, that is, the connection between two horizontal plates. The two horizontal plates can be connected by bolts 33 to achieve a fixed connection between the two steel arch frames 4.

[0050] A steel mesh and longitudinal connecting steel bars are installed in the area where the steel arch frame 4 is located, and shotcrete 5 is applied to the area; both the steel corrugated plate 1 and the steel arch frame 4 are fixedly connected to the full-ring steel arch frame 4.

[0051] Example 2

[0052] This embodiment is based on Embodiment 1, with reference to... Figures 1-3 This paper provides a construction method for a safe and rapid construction structure for tunnels in fractured rock masses, which specifically includes the following steps:

[0053] Step S1: Excavate the tunnel according to the designed cross-sectional shape;

[0054] Step S2: Design the span, waveform, thickness, circumferential and longitudinal width of the corrugated steel plate 1, and design the model and longitudinal spacing of the steel arch frame 4.

[0055] Step S3: Splice the corrugated steel plate 1 on site. After splicing it into a complete ring, use a forklift or steel frame installation machine to lift it onto the construction platform 8. Four lifting jacks 9 are set on the platform 8 to support and fix the corrugated steel plate 1.

[0056] Step S4: Install the steel arch frame 4 at the side wall and quickly fix it with the locking anchor rod 11 or anchor pipe 10;

[0057] Step S5: During the side wall installation process, the workers on the platform 8 carry out anchor bolt 11 work under the protection of the corrugated steel plate 1, and carry out drilling and anchor bolt 11 installation through the pre-reserved anchor bolt 11 holes in the corrugated steel plate 1.

[0058] After step S6, the steel arch frame 4 and anchor rod 11 are installed, the jacking jack 9 is driven to lift the corrugated steel plate 1 to the design height, the steel arch frame 4 and the corrugated steel plate 1 are fixedly connected, and the anchor rod 11 and the corrugated steel plate 1 are welded and fixed.

[0059] Step S7: In the area supported by the steel arch frame 4, steel mesh and longitudinal connecting steel bars are installed, and shotcrete 5 is applied until the designed thickness of shotcrete 5 is achieved.

[0060] Step S8: Cyclic installation, repeating steps S3 to S7 until the longitudinal design section length of the assembled corrugated steel plate 1 is reached;

[0061] Step S9: Construct the full-ring steel frame, weld the full-ring steel frame to the corrugated steel plate 1, and seal it with sprayed concrete 5;

[0062] Step S10: Grout or pour self-compacting concrete through the grouting holes or pouring ports reserved on the corrugated steel plate 1 to fill the space between the corrugated steel plate 1 and the surrounding rock.

[0063] The grouting liquid can be cement grout or high-molecular foam filler such as polyurethane.

[0064] In strata prone to rockbursts, a layer of foam or rubber should be pasted on the upper surface of the corrugated steel plate 1 to reduce the impact of rockbursts on the composite structure and ensure personnel safety.

[0065] Although specific embodiments of the invention have been described in detail with reference to the accompanying drawings, this should not be construed as limiting the scope of protection of this patent. Various modifications and variations that can be made by a person skilled in the art without inventive effort within the scope described in the claims still fall within the scope of protection of this patent.

Claims

1. A construction method for a safe and rapid construction structure for tunnels in fractured rock mass, characterized in that, The construction structure includes: several assembled corrugated steel plates and steel arch frames; the corrugated steel plates are installed in the arch of the tunnel, and the steel arch frames are installed in the sidewalls and invert sections of the tunnel; The corrugated steel plate and the steel arch frame are fixedly connected by connecting components; a steel mesh and longitudinal connecting steel bars are set in the area where the steel arch frame is located, and shotcrete is applied to the area; both the corrugated steel plate and the steel arch frame are fixedly connected to the full-ring steel arch frame. The construction method includes the following steps: S1. Excavate the tunnel according to the designed cross-sectional shape; S2. Design parameters for corrugated steel plates and steel arch frames; S3. On-site splicing of corrugated steel plates into a complete ring section, followed by lifting onto a platform using a forklift or steel frame installation machine, and supporting the corrugated steel plates with four lifting jacks. S4. Install the steel arch frame on the side wall and fix the steel arch frame with locking anchor rods or anchor pipes; S5. During installation on the sidewall, anchor bolts are installed under the protection of corrugated steel plates, and drilling and anchor bolt installation are carried out through the pre-drilled anchor bolt holes in the corrugated steel plates. S6. Drive the lifting jack to lift the corrugated steel plate to the design height, connect the steel arch frame and the corrugated steel plate through the connecting components, and weld the anchor rod and the corrugated steel plate to fix them. S7. Install steel mesh and longitudinal connecting steel bars in the area supported by steel arch frame, and carry out shotcrete operation in the area until the design thickness of shotcrete is reached. S8. Repeat steps S3 to S7 until the longitudinal design length of the assembled corrugated steel sheet is reached. S9. Construct a full-ring steel arch frame, weld the full-ring steel arch frame to the steel arch frame and the steel corrugated plate respectively, and then seal it with sprayed concrete; S10. Grouting or pouring self-compacting concrete is carried out through the grouting holes or pouring ports reserved on the corrugated steel plate to fill the space between the corrugated steel plate and the surrounding rock.

2. The construction method for the safe and rapid construction structure of the fractured rock tunnel according to claim 1, characterized in that: The connecting assembly includes a connecting plate and a flange; the flange is welded to the end of the corrugated steel plate, and the connecting plate is welded to the end of the steel arch frame; the connecting plate and the flange are fixedly connected by bolts.

3. The construction method for the safe and rapid construction structure of the fractured rock tunnel according to claim 1, characterized in that: The parameters of the corrugated steel plate include the span, waveform, plate thickness, circumferential and longitudinal width of the corrugated steel plate; the parameters of the steel arch frame include the model of the steel arch frame and the longitudinal spacing between them.

4. The construction method for the safe and rapid construction structure of the fractured rock tunnel according to claim 1, characterized in that: The grouting in step S10 is cement grout or polyurethane polymer foam filling material.

5. The construction method for the safe and rapid construction structure of the fractured rock tunnel according to claim 1, characterized in that: When in formations prone to rockbursts, a layer of foam or rubber is attached to the upper surface of the corrugated steel sheet.

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