Construction method for in-situ replacement of underground pipeline through broken pipe jacking and pulling method

Abstract

The invention discloses a construction method for in-situ replacement of an underground pipeline through a broken pipe jacking and pulling method. The method comprises the following steps that a pilot hole is drilled from an inspection well at one end of a pipeline to be replaced to an inspection well at the other end through a horizontal directional drilling machine, and the inspection wells at the two ends are communicated; the guide drill bit in the inspection well at the other end is replaced by a reamer drill bit; a self-sealing socket short pipe is installed on the rear portion of the reamer bit, a jacking and pulling mechanism is arranged on the rear portion of the reamer bit, and the self-sealing socket short pipe is anchored in a bearing and pulling mode through the jacking and pulling mechanism; a horizontal directional drilling machine and a reamer bit are used for reverse reaming, meanwhile, a self-sealing socket short pipe is pulled and pushed into a soil layer through a jacking and pulling mechanism, then a next section of short pipe is installed behind a front section of short pipe, a bearing and pulling rod is lengthened, reverse reaming continues to be conducted, the self-sealing socket short pipe is pulled and pushed into the soil layer through the jacking and pulling mechanism, and the self-sealing socket short pipe is pulled and pushed into the soil layer through the jacking and pulling mechanism. And the operation is repeated in this way, reverse reaming and pipeline lengthening are achieved at the same time till the pipeline penetrates through the inspection well on the other side.

Description

Technical Field

[0001] The invention relates to a construction method for replacing underground pipelines in situ using a broken pipe top-pulling method, and belongs to the technical field of pipeline replacement without excavating a road surface. Background Art

[0002] For dredging, inspection and pipeline repair projects, since some sewage pipelines are close to existing house foundations and newly built roads, sewage pipelines need to pass under existing main traffic arteries, etc., there are several difficulties if excavation repair is adopted, such as: large traffic volume and long operation cycle will cause urban traffic congestion and driving safety hazards, and navigation difficulties; the underground comprehensive pipeline network is mature, there are many pipeline intersections, and the construction is difficult; some roads are newly built roads, and the road excavation procedures are difficult and the processing cycle is long; the dust and mud caused by the pile of earth are serious, and the environmental pollution is serious.

[0003] In order to solve the above problems existing in excavation and repair, trenchless methods are often used to replace pipes when encountering such problems in rainwater and sewage diversion, dredging, detection and repair pipeline projects. The trenchless pipeline replacement methods currently used are pipe jacking construction method and directional drilling and traction construction method. Although these two methods have achieved uninterrupted traffic on the road during construction, they face the construction of double-end working surfaces, which temporarily occupy a large area on both sides of the road and affect the surrounding social environment; at the same time, when both sides are close to buildings, they are faced with the problem of being unable to construct. In particular, the pipe jacking construction method requires the establishment of working wells and receiving wells, which causes great damage to the original ground facilities and has a long cycle, and there are certain safety risks for pedestrians in the surrounding area. Summary of the invention

[0004] In view of the above-mentioned defects in the prior art, the present invention provides a new construction method for replacing underground pipelines in situ by the broken pipe top-pulling method. The construction method can reduce the occupation of temporary land and increase the construction speed.

[0005] The present invention is realized by the following technical scheme: a construction method for replacing underground pipelines in situ by the broken pipe top pulling method, wherein the newly replaced pipelines are connected by a plurality of self-sealing short pipes with socket joints, and the method is characterized in that the method comprises the following steps:

[0006] (1) On the working surface at one end of the pipeline, a horizontal directional drilling rig is used to drill a pilot hole from the inspection well at one end of the pipeline to be replaced to the inspection well at the other end according to the designed guide drilling trajectory, so that the inspection wells at both ends of the pipeline to be replaced are connected;

[0007] (2) Remove the pilot drill bit connected to the drill pipe in the inspection well at the other end, and connect the reverse reaming drill bit to the drill pipe;

[0008] (3) A short self-sealing socket joint tube is installed at the rear of the reaming drill bit, and a jacking mechanism is provided at the rear of the reaming drill bit, and the short self-sealing socket joint tube is tensioned and anchored by the jacking mechanism; the jacking mechanism includes an extendable tension rod, a rear anchor top plate and an anchor ring connected to one end of the tension rod, and a hydraulic jack, the other end of the tension rod is connected to the rear end of the reaming drill bit, the short self-sealing socket joint tube is located between the reaming drill bit and the rear anchor top plate, and the hydraulic jack is arranged between the rear anchor top plate and the wall of the inspection well;

[0009] (4) Use a horizontal directional drill and a reaming drill bit to perform reverse reaming, and at the same time, use a jacking mechanism to pull the short self-sealing socket joint pipe up and penetrate into the soil layer, then install the next section of the short self-sealing socket joint pipe behind the previous section, and lengthen the tension rod, use the jacking mechanism to tension and anchor the short self-sealing socket joint pipe again, and then continue to perform reverse reaming, and use the jacking mechanism to pull the short self-sealing socket joint pipe up and penetrate into the soil layer, and repeat this process to achieve reverse reaming and extending the pipe until it penetrates to the inspection well on the other side;

[0010] (5) Fill and seal the redundant drill pipe holes to complete the pipeline renewal and installation.

[0011] In the present invention, a pilot hole is first drilled by a horizontal directional drilling rig using a guide drill bit, and then the reaming drill bit is replaced to perform reverse reaming excavation. At the same time, a self-sealing socket joint short pipe is installed at the rear of the reaming drill bit, and a top-pull mechanism is set to tension and anchor the self-sealing socket joint short pipe. During reverse reaming excavation, the reaming drill bit is used to perform reaming drilling, and at the same time, the pulling force is transmitted back through the tension rod. The connected rear anchor top plate and anchor ring and hydraulic jack are used to reversely pull and top the self-sealing socket joint short pipe into the soil layer to achieve the reaming and top-pull installation of the pipeline. In the present invention, a self-sealing socket joint short pipe is used as an updated pipeline, and its pipe section is light and the length of the pipe section is short. The pipeline connection does not require hot-melt butt connection, the interface is self-locking, earthquake-resistant and shear-resistant, and does not become disconnected. After the pipeline is connected, it is flexible as a whole and can adapt to uneven settlement. It can be used to carry out construction in the limited space of an existing inspection well, and can realize the renewal and replacement of underground pipelines in a limited space.

[0012] Furthermore, in order to ensure the construction accuracy of the pilot hole, the inclined section is drilled first when drilling the pilot hole, and then the transition is made to the horizontal center position of the designed pipeline; the detection control point setting frequency of the inclined section is every 0.5m-1.0m, and the detection control point setting frequency of the straight section is set according to the length of one drill rod.

[0013] Furthermore, the tension rod is formed by connecting a plurality of short drill rods by threads. By connecting the short drill rods by threads, the tension rod can be conveniently extended to adapt to the top extension construction of the pipeline.

[0014] Furthermore, the length of the self-sealing socket joint short tube is 500 mm, and the length of the short drill rod is 500 mm.

[0015] The beneficial effects of the present invention are as follows: the present invention adopts a self-sealing short pipe with a socket joint as an updated pipe, and adopts a specially designed jacking and pulling mechanism for jacking and pulling construction, which can optimize the traditional double-end working surface pipe-threading method to a single-end working surface pipe-threading method, effectively solving the problem of insufficient working surface in the current non-excavation pipeline replacement method, minimizing the damage to the original facilities and reducing the occupation of temporary land. The jacking and pulling construction method of the present invention has the advantages of fast construction speed, accelerated construction progress, and relatively less mechanical equipment invested, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a construction schematic diagram of in-situ replacement of underground pipelines by the broken pipe top-pull method in the present invention;

[0017] In the figure, 1. horizontal directional drilling rig, 2. reaming drill bit, 3. guide drill bit, 4. tension rod, 5. rear anchor top plate and anchor ring, 6. self-sealing socket joint short pipe, 7. hydraulic jack, 8. guide instrument, 9. existing drainage pipe, 10. plugging airbag, 11. existing inspection well I, 12. existing inspection well II. DETAILED DESCRIPTION

[0018] The present invention will be further described below by way of non-limiting embodiments and in conjunction with the accompanying drawings:

[0019] As shown in the attached figure, a construction method for replacing underground pipelines in situ by a broken pipe top-pull method is used to replace HDPE or ceramic pipes. Among them, the newly replaced pipeline is connected by a number of self-sealing short pipes with socket joints. The self-sealing short pipe with socket joints is a prior art, which is a double-sealed self-locking short pipe with socket joints and has the following advantages: A. It has the performance of a solid wall pipe; B. The connection does not require hot-melt butt equipment, and there is no interface inner flange; C. No electricity is required, and construction can also be carried out in a water environment underground; D. The pipeline is light, and the length of the pipe section is 500mm, 1000mm, etc., which is also convenient for installation in a small space, and the length of the pipe section can also be customized; E. The interface is tight and leak-free; F. The interface is self-locking, earthquake-resistant and shear-resistant, and does not disconnect; G. After the pipeline is connected, the whole is flexible and can adapt to uneven settlement. The present invention adopts a self-sealing short pipe with socket joints and a top-pull method to achieve in-situ replacement of underground pipelines. The equipment used in the construction includes a horizontal directional drilling rig 1, a guide instrument 8, a guide drill bit 3, and a reaming drill bit 2, and the above equipment are all prior art.

[0020] It includes the following steps:

[0021] (1) A horizontal directional drilling machine 1 is set on the working surface at one end of the existing drainage pipe 9 to be updated. According to the designed guide drilling trajectory, the horizontal directional drilling machine 1 is used to drill a pilot hole using the guide drill bit 3. When drilling the pilot hole, the inclined section is first drilled, and then the horizontal center position of the designed pipeline is transitioned to. Then, along the center line of the designed pipeline, the existing inspection well Ⅰ11 at one end of the pipeline is drilled to the existing inspection well Ⅱ12 at the other end, so that the inspection wells at both ends of the pipeline to be replaced are connected. The inner diameter of the existing inspection well must be greater than or equal to 1m. The closing part of the upper part of the inspection well can be removed during construction and restored after the pipeline repair is completed.

[0022] In order to ensure the construction accuracy of the pilot hole, the detection control points of the inclined section are set at a frequency of every 0.5m-1.0m, and the detection control points of the straight section are set at a frequency according to the length of a drill rod.

[0023] (2) Remove the guide drill bit 3 connected to the drill pipe in the inspection well II 12 at the other end, and connect the reverse reaming drill bit 2 to the drill pipe. The diameter of the reaming drill bit 2 shall not exceed 50 mm of the outer diameter of the pipe.

[0024] (3) A self-sealing short tube with a socket joint 6 is installed at the rear of the reaming drill bit 2, and a jacking mechanism is provided at the rear of the reaming drill bit 2, and the self-sealing short tube with a socket joint 6 is tension-anchored by the jacking mechanism; the jacking mechanism includes an extendable tension rod 4, a rear anchor top plate and an anchor ring 5 connected to one end of the tension rod 4, and a hydraulic jack 7, the other end of the tension rod 4 is connected to the rear end of the reaming drill bit 2, the self-sealing short tube with a socket joint 6 is located between the reaming drill bit 2 and the rear anchor top plate, and the hydraulic jack 7 is provided between the rear anchor top plate and the well wall of the inspection well II 12.

[0025] (4) Use the horizontal directional drilling rig 1 and the reaming drill bit 2 to carry out reverse reaming, and at the same time, use the jacking mechanism to pull the self-sealing socket joint short pipe 6 up and penetrate into the soil layer, then install the next section of the self-sealing socket joint short pipe 6 after the previous section of the self-sealing socket joint short pipe 6, and extend the tension rod 4, use the jacking mechanism to anchor the self-sealing socket joint short pipe 6 again, and then continue to carry out reverse reaming, and use the jacking mechanism to pull the self-sealing socket joint short pipe up and penetrate into the soil layer, and repeat this process to achieve reverse reaming and extending the pipeline at the same time, until it penetrates to the inspection well Ⅰ11 on the other side. During reverse reaming excavation, the reaming drill bit 2 implements reaming drilling, and at the same time transmits the pulling force back through the tension rod 4, and uses the connected rear anchor top plate and anchor ring 5 and hydraulic jack 7 to pull the self-sealing socket joint short pipe 6 up and penetrate into the soil layer. During the whole process, the pipe is only subjected to the friction resistance of jacking.

[0026] In order to facilitate the extension of the tension rod 4, it is preferred that the tension rod 4 is formed by connecting several short drill rods through threads. External threads are set at both ends of the short drill rods, and they are connected through threaded sleeves when extending. When the tension rod 4 needs to be extended, the rear anchor top plate and the anchor ring 5 are disassembled, and the short drill rod to be connected is connected to the original short drill rod through the threaded sleeve for extension, and then the rear anchor top plate and the anchor ring 5 are connected to the extended tension rod 4. By threading the short drill rod, the tension rod can be easily extended to adapt to the top extension construction of the pipeline.

[0027] Preferably, the length of the self-sealing socket joint short tube is 500 mm, and the length of the short drill rod is 500 mm.

[0028] (5) Fill and seal the redundant drill pipe holes to complete the pipeline renewal and installation.

[0029] The key control points during the construction process are:

[0030] (1) When the first drill rod is drilled into the soil, the method of light pressure and slow rotation should be adopted to stabilize the position of the entry point. Drilling can only be carried out after it meets the designed entry angle. When drilling the pilot hole, the frequency of setting the detection control points of the inclined section and the straight section should be ensured.

[0031] (2) During the construction of the pilot hole, the direction of drilling shall be controlled according to the designed axis of the pipeline and the hydraulic slope. The drill light source must be reliably sealed, the circuit connection must be stable, and the direction-control theodolite must be firmly installed. During the drilling process, the direction-control theodolite axis shall be checked every 20m of drilling.

[0032] (3) The outer diameter of the machine head shall not exceed the outer diameter of the pipeline by 50mm; the distance of the pipeline being pulled up once shall not exceed 80m, and the distance between inspection wells for ordinary pipelines shall be controlled at an accuracy of 20mm-30mm for the pipe opening of each inspection well; after the pipeline is completed, CCTV detection and the internal infiltration method shall be used for tightness inspection.

[0033] (4) The mud for directional drilling and hole expansion should be prepared according to the formation conditions, and the adjustment of mud performance indicators should meet the following requirements: ① The viscosity should be able to maintain the stability of the hole wall and carry the drill cuttings to the surface; ② The water loss of the mud should be controlled at 10-15ml within 30min in general formations; the water loss of water-sensitive, easily collapsed and loose formations should be controlled below 5ml; ③ The pH+ value of the mud should be controlled between 8-10.

[0034] The other parts of this embodiment are all prior art and will not be described in detail here.

Claims

1. A construction method for replacing underground pipelines in situ by using a broken pipe top-pull method, wherein the newly replaced pipelines are connected by a plurality of short self-sealing socket joints, and the characteristics are: The steps include: (1) On the working surface at one end of the pipeline, a horizontal directional drilling rig is used to drill a pilot hole from the inspection well at one end of the pipeline to be replaced to the inspection well at the other end according to the designed guide drilling trajectory, so that the inspection wells at both ends of the pipeline to be replaced are connected; (2) Remove the pilot drill bit connected to the drill pipe in the inspection well at the other end, and connect the reverse reaming drill bit to the drill pipe; (3) A short self-sealing socket joint tube is installed at the rear of the reaming drill bit, and a jacking mechanism is provided at the rear of the reaming drill bit, and the short self-sealing socket joint tube is tensioned and anchored by the jacking mechanism; the jacking mechanism includes an extendable tension rod, a rear anchor top plate and an anchor ring connected to one end of the tension rod, and a hydraulic jack, the other end of the tension rod is connected to the rear end of the reaming drill bit, the short self-sealing socket joint tube is located between the reaming drill bit and the rear anchor top plate, and the hydraulic jack is arranged between the rear anchor top plate and the wall of the inspection well; (4) Use a horizontal directional drill and a reaming drill bit to perform reverse reaming, and at the same time, use a jacking mechanism to pull the short self-sealing socket joint pipe up and penetrate into the soil layer, then install the next section of the short self-sealing socket joint pipe behind the previous section, and lengthen the tension rod, use the jacking mechanism to tension and anchor the short self-sealing socket joint pipe again, and then continue to perform reverse reaming, and use the jacking mechanism to pull the short self-sealing socket joint pipe up and penetrate into the soil layer, and repeat this process to achieve reverse reaming and extending the pipe until it penetrates to the inspection well on the other side; (5) Fill and seal the redundant drill pipe holes to complete the pipeline renewal and installation.

2. The construction method for replacing underground pipelines in situ by the broken pipe top-pull method according to claim 1 is characterized by: When drilling the pilot hole, drill the inclined section first and then transition to the designed horizontal center position of the pipeline; the detection control point setting frequency of the inclined section is every 0.5m-1.0m, and the detection control point setting frequency of the straight section is set according to the length of one drill rod.

3. The construction method for replacing underground pipelines in situ by the broken pipe top pulling method according to claim 1 or 2 is characterized by: The tension rod is formed by connecting a plurality of short drill rods through threads.

4. The construction method for replacing underground pipelines in situ by the broken pipe top-pull method according to claim 3 is characterized by: The length of the self-sealing socket joint short pipe is 500 mm, and the length of the short drill rod is 500 mm.

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