Tunnel high-precision long pipe shed construction method without chamber

Abstract

The invention discloses a tunnel high-precision long pipe shed construction method without a chamber, which comprises the following steps: setting up a guide frame outside a tunnel portal, mounting drilling equipment, mounting a guide pipe at the top of the guide frame, and mounting the drilling equipment at the top of the guide frame; an included angle of 15-20 degrees is formed between the inclination direction of the guide pipe and the extension direction of the tunnel; then drilling equipment drills into a tunnel rock stratum at an outer insertion angle of 15-20 in the extending direction of the tunnel under the guiding effect of the guiding pipe, a plurality of drill holes are distributed at intervals along the outline of a tunnel portal, each drill hole corresponds to one long pipe, the long pipes are inserted into the corresponding drill holes, then grouting is conducted on the long pipes, and a first ring pipe shed is formed at the tunnel portal after grouting reinforcement is completed; combining the angle and length of the long pipe and the front end position of the long pipe, inferring the position of the construction tail end of the previous annular pipe shed in the tunnel rock stratum, calculating the position of the construction starting end of the next annular pipe shed, and enabling the projection of the construction tail end of the previous annular pipe shed and the projection of the construction starting end of the next annular pipe shed to be overlapped in the same horizontal plane; and the tunnel is excavated to the construction starting end position of the next annular pipe shed, then the guide frame is moved in place, drilling, pipe inserting and grouting construction are continued, and construction of the whole section of tunnel pipe shed is completed. The method has the effect of improving the construction safety and the construction efficiency.

Description

Technical Field

[0001] The present application relates to the field of tunnel construction, and in particular to a high-precision long-tube shed construction method for tunnels that does not require a chamber. Background Art

[0002] In tunnel construction, especially when crossing loose, water-rich, soft and broken unfavorable geological conditions, the construction is difficult and risky. In order to ensure the safety and stability of tunnel construction, effective advance support measures need to be taken. As an advanced support technology, long pipe shed support is widely used in tunnel construction due to its good support effect, high construction efficiency and strong adaptability. As an underground space structure, the chamber provides the necessary construction space and working platform for the long pipe shed construction of the tunnel.

[0003] During the construction of the long pipe shed, advanced drilling equipment is used to drill holes on the tunnel wall, clean up the debris in the hole, and install the prepared long pipes (generally seamless steel pipes) into the drilled holes one by one. Slurry materials with filling and gel properties are injected into the long pipes to reinforce the loose and broken rock layers through the hardening effect of the gel. After the grouting reinforcement is completed, a support shed is built to cover and protect the tunnel to ensure the safety and stability of the tunnel construction. Then excavation is carried out along the tunnel construction direction. When the excavation depth reaches the far end of the long pipe, it is necessary to over-excavate a distance forward in the tunnel to form a chamber. The sides and top of the inner wall of the chamber need to be widened. Then the drilling rig, grouting equipment and other construction machinery are arranged in the widened space of the chamber to provide space for horizontal drilling operations and horizontal jacking to ensure the alignment of the long pipes.

[0004] Regarding the above-mentioned related technologies, the applicant believes that the following defects exist: However, under loose geological conditions, there is a lack of support during over-excavation, the safety is low, and the construction chamber will also affect the efficiency of tunnel construction, so there is still room for improvement. Summary of the invention

[0005] In order to improve construction safety and efficiency, the present application provides a high-precision long-tube shed construction method for a tunnel without the need for a chamber.

[0006] The present application provides a tunnel high-precision long pipe shed construction method without a chamber, which adopts the following technical solution: A high-precision long-tube shed construction method for a tunnel without a chamber comprises the following steps: S1: A guide frame is set up outside the tunnel entrance and drilling equipment is installed. A guide tube is installed on the top of the guide frame. The inclination direction of the guide tube is at an angle of 15° to 20° with the extension direction of the tunnel. S2: Under the guidance of the guide tube, the drilling equipment drills into the tunnel rock layer at an external insertion angle of 15° to 20° along the tunnel extension direction. Several boreholes are spaced along the tunnel entrance contour. Each borehole corresponds to a long tube. The long tube is inserted into the corresponding borehole, and then grouting is injected into the long tube. After the grouting reinforcement is completed, the first ring pipe shed is formed at the tunnel entrance; S3: Based on the angle, length and front end position of the long pipe, the position of the construction end of the previous pipe shed in the tunnel rock layer is inferred, and the construction start position of the next pipe shed is calculated. The construction end of the previous pipe shed and the construction start position of the next pipe shed overlap in the projection on the same horizontal plane, and the tunnel is excavated to the construction start position of the next pipe shed, and then the guide frame is moved into place; S4: Repeat S2 and S3 to complete the pipe shed construction of the entire tunnel.

[0007] By adopting the above technical scheme, drilling, pipe insertion and grouting reinforcement construction are carried out at an external insertion angle of 15º to 20º to form a ring of pipe sheds. The pipe shed widens from the construction starting end to the construction end. When constructing the next ring of pipe sheds, the construction starting end position of the next ring of pipe sheds is first calculated to ensure that the construction end of the previous ring of pipe sheds and the construction starting end of the next ring of pipe sheds overlap in the projection on the same horizontal plane. Therefore, when excavating the tunnel to the construction starting end position of the next ring of pipe sheds, the inner wall of the tunnel is still supported by the construction end of the previous ring of pipe sheds, so there is no need to over-excavate forward to form a chamber, which is beneficial to improving the safety and construction efficiency of tunnel pipe shed construction.

[0008] Preferably, the diameter of the long tube is 150 mm to 170 mm.

[0009] By adopting the above technical solution, using 150mm-170mm long diameter pipes as pipe-roof steel pipes can significantly improve the rigidity and strength of the support structure and more effectively resist the pressure and deformation of the surrounding soil. This helps to protect the stability of the stratum above the construction area and prevent safety accidents such as collapse. The long large diameter pipe provides a wider channel for grouting operations, making the grouting process smoother to form a solid reinforcement layer and further improve the support effect.

[0010] Preferably, the length of the long pipe is 1200 mm, and the distance between the construction end of the previous ring pipe shed and the construction start end of the next ring pipe shed is 350 mm to 450 mm.

[0011] By adopting the above technical scheme, the overlapping length of the construction end of the previous ring pipe shed and the construction starting end of the next ring pipe shed is set between 350mm and 450mm, so that the construction of the next ring pipe shed can be carried out under the effective support of the construction end of the previous ring pipe shed, which is beneficial to improving the safety and efficiency of tunnel pipe shed construction.

[0012] Preferably, after completing the construction of a ring of pipe sheds in S2, a primary lining structure is built on the inner wall of the tunnel, and the construction starting end of the pipe shed is buried in the primary lining structure.

[0013] By adopting the above technical solution, after completing the construction of one ring of the pipe shed, the primary lining structure is promptly built on the inner wall of the tunnel to strengthen the structural strength of the inner wall of the tunnel, and the starting end of the pipe shed construction is buried in the primary lining structure, which is beneficial to improving the structural stability of the pipe shed.

[0014] Preferably, the guide frame includes a frame body and a plurality of adjustment components arranged at the frame body, the plurality of adjustment components are spaced apart along the width direction of the frame body and correspond one-to-one to the plurality of guide tubes, and the adjustment components are used to adjust the angles of the corresponding guide tubes.

[0015] By adopting the above technical solution, the angle of the guide tube can be adjusted according to the construction conditions under the adjustment of the adjustment component, which is beneficial to improving the adaptability of the guide frame. Multiple adjustment components are matched with multiple guide tubes, so that multiple drilling constructions can be carried out simultaneously, and drilling construction and pipe insertion construction can also be carried out at different positions.

[0016] Preferably, the adjustment assembly includes two top support rods and two vertical jacks, the two top support rods are respectively vertically slidably connected to the front end and the rear end of the guide frame, and slide grooves are provided on both sides of the guide tube, and the length of the slide grooves is consistent with the length of the guide tube; the top of the top support rod is provided with connecting rods located on both sides of the guide tube, the connecting rods are rotatably connected in the slide grooves of the guide tube, and the connecting rods can slide relatively along the length direction of the guide tube; the two vertical cylinders correspond one-to-one to the two top support rods, and the two vertical cylinders are respectively installed at the bottom of the corresponding top support rods to drive the corresponding top support rods to slide up and down.

[0017] By adopting the above technical solution, when the two vertical jacks are extended and retracted synchronously and their extension and retraction lengths are consistent, the corresponding guide tubes can be raised and lowered while maintaining an unchanged inclination angle. When the two vertical jacks are extended and retracted in opposite directions, the corresponding guide tubes can be adjusted at an unchanged height position. This is beneficial to improving the flexibility of the guide frame and the guide tube, so as to be applied to the construction steps of an arc-shaped tunnel pipe shed.

[0018] Preferably, the frame body includes a plurality of truss units, and the plurality of truss units are assembled in sequence up and down.

[0019] By adopting the above technical solution, the frame body is assembled from a plurality of truss units, which is convenient for transportation and on-site installation, and can be assembled according to construction conditions to change the height of the frame body.

[0020] Preferably, universal wheels are installed at the bottom of the frame body.

[0021] By adopting the above technical solution, universal wheels are installed at the bottom of the frame body to facilitate the movement of the position of the guide frame to adapt to drilling and pipe insertion construction at different positions.

[0022] In summary, the present application includes at least one of the following beneficial technical effects: 1. Through drilling and pipe insertion and grouting reinforcement construction at an external insertion angle of 15º to 20º, a ring of pipe shed is formed. The pipe shed widens from the construction start end to the construction end end. When constructing the next ring of pipe shed, the construction start end position of the next ring of pipe shed is calculated first to ensure that the construction end of the previous ring of pipe shed and the construction start end of the next ring of pipe shed overlap in the projection on the same horizontal plane. Therefore, when the tunnel is excavated to the construction start end position of the next ring of pipe shed, the inner wall of the tunnel is still supported by the construction end of the previous ring of pipe shed, so there is no need to over-excavate forward to form a chamber, which is conducive to improving the safety and construction efficiency of tunnel pipe shed construction; 2. After completing the construction of one ring of the pipe shed, the primary lining structure is promptly built on the inner wall of the tunnel to strengthen the structural strength of the inner wall of the tunnel. The construction start end of the pipe shed is buried in the primary lining structure, which is conducive to improving the structural stability of the pipe shed; 3. The angle of the guide tube can be adjusted according to the construction conditions under the adjustment of the adjustment component, which is conducive to improving the adaptability of the guide frame. Multiple adjustment components are matched with multiple guide tubes, so that multiple drilling constructions can be carried out simultaneously, and drilling construction and pipe insertion construction can also be carried out at different positions; 4. Two vertical jacks are used to drive two top support rods respectively to adjust the angle and height of the guide tube. When the two vertical jacks are extended and retracted synchronously and the extension lengths are consistent, the corresponding guide tubes are lifted and lowered while maintaining an unchanged inclination angle. When the two vertical jacks are extended and retracted in opposite directions, the corresponding guide tubes are adjusted while maintaining an unchanged height position. This is beneficial to improving the flexibility of the guide frame and the guide tube, so that it can be applied to the construction steps of the arc-shaped tunnel pipe shed. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the positions of adjacent pipe sheds in a method for constructing a high-precision long pipe shed in a tunnel without a chamber according to an embodiment of the present application.

[0024] Figure 2 It is a side view of a guide frame in a high-precision long-tube shed construction method for a tunnel without a chamber according to an embodiment of the present application.

[0025] Figure 3 It is a top view of a guide frame in a high-precision long-tube shed construction method for a tunnel without a chamber according to an embodiment of the present application.

[0026] Explanation of the reference numerals: 1. tunnel; 2. pipe shed; 3. primary lining structure; 4. guide frame; 41. frame body; 411. truss unit; 42. adjustment assembly; 421. vertical jack; 422. top support rod; 423. steel corbel; 424. connecting rod; 43. universal wheel; 5. guide pipe; 51. slide chute; 6. I-beam. DETAILED DESCRIPTION

[0027] The following is combined with Figure 1-3 This application is described in further detail.

[0028] The present application embodiment discloses a high-precision long pipe shed construction method for a tunnel without a chamber, referring to Figure 1 and Figure 2 , comprising the following steps:.

[0029] S1: A guide frame 4 is set up outside the tunnel 1 opening and drilling equipment is installed. A guide pipe 5 is installed on the top of the guide frame 4, and the inclined direction of the guide pipe 5 is at an angle of 15° to 20° with the extension direction of the tunnel 1.

[0030] Reference Figure 2 and Figure 3 The guide frame 4 includes a frame body 41 and a plurality of adjustment components 42 installed at the frame body 41. The plurality of adjustment components 42 are spaced apart along the width direction of the frame body 41 and correspond to the plurality of guide tubes 5 one by one. The adjustment components 42 are used to adjust the angle of the corresponding guide tubes 5. The frame body 41 includes a plurality of truss units 411. The plurality of truss units 411 are assembled up and down for easy transportation and on-site installation, and can be assembled according to the construction conditions to change the height of the frame body 41. In addition, a universal wheel 43 is installed at the bottom of the frame body 41. This is to facilitate the movement of the position of the guide frame 4 to adapt to the drilling and pipe insertion construction at different positions of the tunnel 1.

[0031] Reference Figure 2 and Figure 3 The adjustment assembly 42 includes two top support rods 422 and two vertical jacks 421. The two top support rods 422 are vertically slidably connected to the front end and the rear end of the guide frame 4 respectively. The top support rods 422 use the vertical I-beams 6 on both sides as slide rails to improve the sliding stability of the top support rods 422.

[0032] In this embodiment, both sides of the guide tube 5 are provided with a slide groove 51, and the length of the slide groove 51 is consistent with the length of the guide tube 5. The top of the top support rod 422 is provided with a connecting rod 424 located on both sides of the guide tube 5, and the connecting rod 424 is rotatably connected to the slide groove 51 of the guide tube 5, and the connecting rod 424 can slide relatively along the length direction of the guide tube 5. The connecting rod 424, as the connecting axis of the guide tube 5, can realize the rotation function of the guide tube 5, and can also improve the flexibility of the guide tube 5 through the sliding connection between the connecting rod 424 and the slide groove 51, so as to facilitate the adjustment of the angle of the guide tube 5.

[0033] The two vertical cylinders are fixed to the frame body 41 through steel brackets 423 and correspond to the two top support rods 422 one by one. The two vertical cylinders are respectively installed at the bottom of the corresponding top support rods 422 to drive the corresponding top support rods 422 to slide up and down. When the two vertical jacks 421 are synchronously extended and retracted, and the extension lengths are consistent, the corresponding guide tube 5 can be lifted and lowered at a constant inclination state. When the two vertical jacks 421 are extended and retracted in opposite directions, the corresponding guide tube 5 can be adjusted at a constant height position, which is conducive to improving the flexibility of the guide frame 4 and the guide tube 5, so as to be applied to the construction steps of the tunnel 1 pipe shed 2 arranged in an arc shape.

[0034] S2: The drilling equipment can be a pipe-roof 2 drilling rig or a down-the-hole drilling rig. Before drilling, it is necessary to adjust the height and angle of the guide tube 5, and perform measurement and correction. Then, the drilling equipment is installed at the rear end of the frame body 41, and the drill rod is aligned with the guide tube 5. The drilling equipment rotates and pushes the drill rod under the guidance of the guide tube 5. The drill rod is drilled into the rock formation of the tunnel 1 at an external insertion angle of 15º to 20º along the extension direction of the tunnel 1. In this embodiment, the external insertion angle of the borehole is 18º. After the drilling is completed, the rock slag and mud in the hole are cleaned to ensure that the hole is unobstructed.

[0035] Several boreholes are spaced along the contour of the tunnel 1 opening, each of which corresponds to a long pipe, which is inserted into the corresponding borehole through the guide pipe 5. The pipe insertion step can be completed by mechanical jacking. During the jacking process, the jacking speed and jacking force of the steel pipe must be strictly controlled to prevent the steel pipe from bending or damage.

[0036] Then cement slurry or chemical slurry is used for grouting reinforcement. The grouting adopts the backward segmented grouting or forward segmented grouting method to ensure uniform and dense grouting. By grouting into the long pipe, the slurry flows through the holes around the long pipe to the rock layer of tunnel 1, and the loose and broken rock layer is reinforced by gel hardening. Prevent the slurry from flowing out. After the grouting reinforcement is completed, the tail of the steel pipe is sealed to form the first ring pipe shed 2 at the entrance of tunnel 1.

[0037] It should be noted that the guide frame 4 is mainly used for drilling and pipe insertion construction at the top position of the tunnel 1 and the upper positions on both sides. The lower positions on both sides of the tunnel 1 are relatively low, and a simple fixed guide frame 4 can be used in conjunction with the guide pipe 5 to carry out the construction of the pipe rack 2.

[0038] When constructing the pipe shed 2 at the top of the tunnel 1 , the position of the guide frame 4 can be adjusted by translating and rotating the frame body 41 , and then the guide frame 4 can be locked by temporarily fixing it.

[0039] Multiple guide tubes 5 are used to perform drilling construction and pipe insertion construction at different positions. It is only necessary to keep the position of the guide frame 4 unchanged, and then adjust the height of each guide tube 5 according to the arc surface at the top of the tunnel 1. The guide tube 5 at the drilling construction site can be used for pipe insertion construction first, thereby improving the construction efficiency of the pipe rack 2.

[0040] S3: Based on the angle, length and front end position of the long pipe, the position of the construction end of the previous ring pipe shed 2 in the rock layer of the tunnel 1 is inferred, and then the construction start end position of the next ring pipe shed 2 is calculated, and the construction end of the previous ring pipe shed 2 overlaps with the construction start end of the next ring pipe shed 2 in the projection on the same horizontal plane. In this embodiment, the diameter size of the long pipe can be selected from 150mm to 170mm, and specifically a steel pipe with a diameter of 159mm and a length of 1200mm is used.

[0041] After completing the construction steps of a ring of pipe shed 2, the primary lining structure 3 is built on the inner wall of the tunnel 1, and the construction starting end of the pipe shed 2 is buried in the primary lining structure 3 to strengthen the structural strength of the inner wall of the tunnel 1 and improve the structural stability of the pipe shed 2.

[0042] Then, the tunnel 1 is excavated to the construction starting end position of the next ring pipe shed 2, and the distance between the construction end of the previous ring pipe shed 2 and the construction starting end of the next ring pipe shed 2 is 350mm-450mm, so that the length dimension of the overlap between the construction end of the previous ring pipe shed 2 and the construction starting end of the next ring pipe shed 2 is between 350mm and 450mm, so that the construction of the next ring pipe shed 2 can be carried out under the effective support of the construction end of the previous ring pipe shed 2, which is conducive to improving the safety and construction efficiency of the construction of the tunnel 1 pipe shed 2. Then, the guide frame 4 is moved into place to prepare for drilling, pipe insertion and grouting construction.

[0043] S4: Repeat S2 and S3 to complete the construction of the pipe shed 2 of the entire tunnel.

[0044] In this embodiment, drilling, pipe insertion and grouting reinforcement construction are carried out at an external insertion angle of 15º to 20º to form a ring of pipe shed 2. The pipe shed 2 widens from the construction starting end to the construction end. When constructing the next ring of pipe shed 2, the construction starting end position of the next ring of pipe shed 2 is first calculated to ensure that the construction end of the previous ring of pipe shed 2 and the construction starting end of the next ring of pipe shed 2 overlap in the projection on the same horizontal plane. Therefore, when excavating the tunnel 1 to the construction starting end position of the next ring of pipe shed 2, the inner wall of the tunnel 1 is still under the support of the construction end of the previous ring of pipe shed 2, so there is no need to over-excavate forward to form a chamber, which is beneficial to improving the safety and construction efficiency of the tunnel 1 pipe shed 2 construction.

[0045] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A high-precision long-tube shed construction method for a tunnel without a chamber, characterized in that: The following steps are involved: S1: A guide frame (4) is set up outside the tunnel (1) opening and a drilling device is installed, a guide tube (5) is installed on the top of the guide frame (4), and the inclination direction of the guide tube (5) is at an angle of 15° to 20° with the extension direction of the tunnel (1); S2: Under the guidance of the guide pipe (5), the drilling equipment drills into the rock layer of the tunnel (1) at an external insertion angle of 15° to 20° along the extension direction of the tunnel (1). A plurality of boreholes are distributed at intervals along the contour of the tunnel (1) opening. Each borehole corresponds to a long pipe. The long pipe is inserted into the corresponding borehole, and then grouting is injected into the long pipe. After the grouting reinforcement is completed, a first ring pipe shed (2) is formed at the tunnel (1) opening. S3: Based on the angle, length and front end position of the long pipe, the position of the construction end of the previous pipe shed (2) in the rock layer of the tunnel (1) is inferred, and the construction start position of the next pipe shed (2) is calculated. The construction end of the previous pipe shed (2) and the construction start position of the next pipe shed (2) overlap in projection on the same horizontal plane, and the tunnel (1) is excavated to the construction start position of the next pipe shed (2), and then the guide frame (4) is moved into place; S4: Repeat S2 and S3 to complete the construction of the entire tunnel (1) and pipe shed (2).

2. According to claim 1, a high-precision long-tube shed construction method for a tunnel without a chamber is characterized in that: The diameter of the long tube is 150 mm to 170 mm.

3. The method for constructing a high-precision long pipe shed in a tunnel without a chamber according to claim 1, characterized in that: The length of the long pipe is 1200 mm, and the distance between the construction end of the previous ring pipe shed (2) and the construction start end of the next ring pipe shed (2) is 350 mm to 450 mm.

4. The method for constructing a high-precision long pipe shed in a tunnel without a chamber according to claim 1, characterized in that: After completing the construction of a ring of pipe shed (2) of S2, a primary lining structure (3) is built on the inner wall of the tunnel (1), and the construction starting end of the pipe shed (2) is buried in the primary lining structure (3).

5. The high-precision long-tube shed construction method for a tunnel without a chamber according to claim 1 is characterized in that: The guide frame (4) comprises a frame body (41) and a plurality of adjustment components (42) arranged on the frame body (41); the plurality of adjustment components (42) are spaced apart along the width direction of the frame body (41) and correspond one-to-one to the plurality of guide tubes (5); the adjustment components (42) are used to adjust the inclination angle of the corresponding guide tube (5).

6. The method for constructing a high-precision long-tube shed in a tunnel without a chamber according to claim 5, characterized in that: The adjustment assembly (42) comprises two supporting rods (422) and two vertical jacks (421). The two supporting rods (422) are respectively vertically slidably connected to the front end and the rear end of the guide frame (4). Both sides of the guide tube (5) are provided with slide grooves (51), and the length of the slide grooves (51) is consistent with the length of the guide tube (5). The top of the supporting rod (422) is provided with connecting rods (424) located on both sides of the guide tube (5). The connecting rods (424) are rotatably connected to the slide grooves (51) of the guide tube (5), and the connecting rods (424) can slide relatively along the length direction of the guide tube (5). The two vertical cylinders correspond to the two supporting rods (422) one by one. The two vertical cylinders are respectively installed at the bottom of the corresponding supporting rods (422) to drive the corresponding supporting rods (422) to slide up and down.

7. The method for constructing a high-precision long pipe shed in a tunnel without a chamber according to claim 5, characterized in that: The frame body (41) comprises a plurality of truss units (411), and the plurality of truss units (411) are assembled in sequence up and down.

8. The method for constructing a high-precision long-tube shed in a tunnel without a chamber according to claim 5, characterized in that: A universal wheel (43) is installed at the bottom of the frame body (41).

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