A construction method for pipeline crossing existing line

Abstract

The pipeline crossing existing line construction method relates to the pipeline installation technical field. Mainly to solve the problem of pipeline crossing existing line construction backfill quality cannot be guaranteed. The existing line pavement is cut, after the foundation pit excavation is completed, the box culvert cushion template support and concrete pouring are carried out. The box culvert bottom plate and part of the side wall steel bar binding, template support, water stop belt installation are carried out, and the concrete pouring of the box culvert bottom structure is carried out. After the box culvert side wall steel bar binding, template support and water stop belt installation are carried out, the concrete pouring of the side wall is carried out, and after the box culvert side wall concrete pouring is condensed and the mold is removed, the pipe crossing pipeline in the box culvert and the platform backfill are constructed synchronously. The gap between the box culvert and the pipeline is backfilled with sand gravel and original soil, the top of the backfilled original soil is shaped, the concrete box culvert top plate cushion is poured along the top of the backfilled soil, which serves as the base surface and inner mold for the box culvert top construction; finally, the concrete pouring of the box culvert top plate is carried out. The advantage is that the backfill quality is good.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pipeline installation, in particular to a pipeline crossing existing line construction method. BACKGROUND

[0002] With the continuous improvement of infrastructure construction technology in China, the development of large-diameter pipeline long-distance installation construction is becoming increasingly rapid, and the number of pipeline crossing existing lines is also increasing. During the construction of crossing existing lines, the "box before pipe" construction method of crossing pipeline in box culvert is usually adopted, that is, the box culvert is constructed first, and then the pipeline is pulled to cross the box culvert. At the same time, in order to do a good job in pipeline insulation and reduce the vibration of the pipeline during operation, backfill material is used to fill between the box culvert and the pipeline.

[0003] Because the gap between the box culvert and the pipeline is small, mechanical equipment cannot enter. During construction, not only time and effort are wasted, but also the backfill at the intersection with the top plate is usually not dense, there are gaps, and the quality of the backfill cannot be guaranteed. In addition, full-frame and inner mold need to be erected during the construction of the box culvert top plate, which increases the labor and construction cost. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a pipeline crossing existing line construction method which is simple in construction, low in engineering cost, fast in construction speed and high in quality.

[0005] To solve the above technical problems, the present application adopts the following technical solutions:

[0006] Firstly, the present method is based on large excavation construction, and the foundation pit is excavated with slope. Before the construction of the box culvert, the existing line is temporarily diverted and changed to ensure the smoothness of the existing line.

[0007] Secondly, the existing line surface is cut before the excavation of the foundation pit, and then the excavation is carried out. After the excavation is completed and the joint acceptance is qualified, the box culvert cushion formwork is set and the concrete is poured. After the box culvert cushion concrete is set, the box culvert bottom plate and part of the side wall reinforcement are bound, the formwork is set, the water stop belt is installed, and then the concrete is poured. The poured concrete this time is the bottom plate and the part 30cm above the bottom corner elevation, that is, the bottom structure of the box culvert.

[0008] Thirdly, the box culvert side wall reinforcement is bound, the formwork is set, the water stop belt is installed, and then the side wall concrete is poured. The poured concrete this time is the part 10cm below the top corner elevation of the box culvert, and the box culvert top plate reinforcement connecting rod is pre-embedded during the reinforcement binding.

[0009] Fourthly, after the box culvert side wall concrete pouring is set and the formwork is removed, the pipeline crossing in the box culvert and the backfill of the platform back are constructed synchronously. This time, the backfill of the platform back is filled to the elevation position of the constructed side wall.

[0010] Fifth, backfill the gap between the box culvert and the installed pipeline. After the pipeline installation is qualified, immediately compact the area below 120° of the pipeline axle with gravel. For areas where mechanical compaction is not possible, use manual symmetrical filling and compact in layers with a tamping hammer to avoid unevenness and settlement. For areas above 120° of the pipeline axle on both sides, use the original soil for backfilling. Use a backhoe excavator to deliver the material to the backfill area and compact in layers with a light compaction tool. Do not directly dump backfill material above the pipeline to avoid incomplete compaction and segregation of the fill material. Backfilling on both sides should be carried out simultaneously and evenly, and the height difference between the two sides should be less than the thickness of one layer of fill. The backfilling height in this case is 10cm below the top slab and the top axle.

[0011] Sixth, the top of the backfill soil inside the box culvert is manually shaped (to the same shape as the top slab and top haunch of the box culvert), and a 10cm thick C15 concrete box culvert top slab cushion layer is poured along the top of the shaped backfill soil as the base surface and inner formwork for the construction of the top of the box culvert.

[0012] Seventh, then carry out the reinforcement binding of the box culvert top slab and top corner, waterstop installation, and outer formwork erection, and finally pour the concrete for the box culvert top slab.

[0013] Eighth, the existing line will be restored. After restoration, the road surface structure will be the same as the existing line surface structure, and traffic will resume.

[0014] The advantages of this invention are: simple construction, low project cost, fast construction speed, and high backfill quality. Compared with other construction methods, this method does not require the erection of full-span scaffolding and internal formwork when constructing the top slab of the box culvert, which not only saves labor and material costs but also improves the construction safety factor. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the interior of the box culvert and the backfill status of the abutment in this invention;

[0016] Figure 2 This is a schematic diagram of the construction status of the box culvert top slab cushion layer of the present invention;

[0017] Figure 3 This is a schematic diagram of the construction status of the box culvert top slab of the present invention;

[0018] Figure 4 This is a schematic diagram of the cross-sectional structure of the present invention. Detailed Implementation

[0019] The following is combined with Figures 1-4 The present invention will be further described;

[0020] It includes the following steps:

[0021] Firstly, the method is based on large excavation construction, and the foundation pit 1 is excavated with slope. Before the box culvert construction, the existing line is temporarily diverted to ensure the smoothness of the existing line.

[0022] Secondly, the existing line pavement 2 is cut before the excavation of the foundation pit, and then the excavation is carried out. After the excavation is completed and the joint acceptance is qualified, the box culvert cushion formwork is set up and the box culvert cushion concrete is poured. After the box culvert cushion 3 concrete is set, the box culvert bottom plate and part of the side wall reinforcement are bound, the formwork is set up, the water stop is installed, and then the concrete is poured. This time, the concrete is poured for the bottom plate and the bottom corner elevation up to 30 cm, which is the bottom structure 4 of the box culvert.

[0023] Thirdly, the box culvert side wall reinforcement is bound, the formwork is set up, the water stop is installed, and then the side wall 5 concrete is poured. This time, the concrete is poured for the box culvert top corner elevation down to 10 cm, and the box culvert top plate reinforcement connecting rod 6 is pre-embedded during the reinforcement binding.

[0024] Fourthly, after the box culvert side wall concrete pouring is set and the formwork is removed, the pipe passing through the box culvert 7 and the backfilling of the platform 8 are constructed synchronously. This time, the platform backfilling is carried out to the elevation position of the constructed side wall.

[0025] Fifthly, the gap between the box culvert and the passing pipe is backfilled. After the pipe installation is qualified, the sand and gravel 9 is used to tamp and fill the parts below the 120° corner of the pipe. The parts that cannot be tamped by machinery are filled by manual symmetrical filling, and the parts are tamped by layering with a rammer to avoid uneven settlement. The parts above the 120° corner of the pipe on both sides are backfilled with original soil 10, which is fed to the backfilling position by a backhoe excavator, and is compacted by layering with a light compaction tool. The backfilling material should not be directly poured on the top of the pipe to avoid leakage and segregation of the filling material. The two sides should be filled uniformly and rise simultaneously, and the height difference between the two sides should be less than the thickness of one layer of filling. The filling height this time is 10 cm below the top plate and top corner of the box culvert.

[0026] Sixthly, the upper part of the backfilled original soil inside the box culvert is manually shaped (shaped into the same shape as the top plate and top corner of the box culvert), and a 10 cm thick C15 concrete box culvert top plate cushion 11 is poured along the top of the shaped backfilled soil, which serves as the base surface and internal formwork for the top construction of the box culvert.

[0027] Seventhly, the reinforcement binding, water stop installation and outside formwork setting of the box culvert top plate and top corner are carried out, and finally the concrete pouring of the box culvert top plate 12 is carried out.

[0028] Eighthly, the existing line is restored, and the pavement structure after restoration is the same as the existing line pavement structure, and the traffic is restored.

[0029] While embodiments of the application have been shown and described, it is to be understood that the application is not limited to the details of the embodiments described, since numerous changes, modifications, substitutions and variations could be made thereto by those skilled in the art without departing from the spirit of the application as defined by the following claims and their equivalents.

Claims

1. A method of constructing a pipeline crossing an existing line, characterised in that: It comprises the following steps:

1. The method is based on large excavation construction, and the foundation pit is excavated with slope; 2. Before the excavation of the foundation pit, the existing pavement is cut, then excavated, after the excavation is completed, the box culvert cushion formwork is set and the box culvert cushion concrete is poured; after the box culvert cushion concrete is set, the box culvert bottom plate and part of the side wall reinforcement are bound, the formwork is set, the water stop is installed, then the concrete is poured, and the concrete poured this time is the bottom plate and the part 30cm above the bottom corner elevation; 3. Then the box culvert side wall reinforcement is bound, the formwork is set, the water stop is installed, and then the box culvert side wall concrete is poured, and the concrete poured this time is the part 10cm below the top corner elevation of the box culvert, and the embedded box culvert top plate reinforcement connecting rod is pre-buried during the reinforcement binding; 4. After the box culvert side wall concrete pouring is set and the formwork is removed, the pipe passing through the box culvert and the backfilling of the platform are constructed synchronously, and the platform backfilling is carried out to the position of the side wall elevation that has been constructed; 5. The gap between the box culvert and the pipe passing through is backfilled, and after the pipe installation is qualified, the sand and gravel are used to tamp the parts below 120° of the pipe corner, the parts that cannot be tamped by machinery are filled with artificial symmetrical materials, and the tamping hammer is used for layered tamping; the parts above 120° of the pipe corner on both sides are backfilled with original soil, and the backfilling parts are fed by using a backhoe excavator, and are layered and compacted by using a compaction tool; both sides are backfilled uniformly and rise at the same time, and the backfilling filling height is 10cm below the box culvert top plate and the top corner; 6. The upper part of the backfilling original soil filled in the box culvert is manually shaped to the same shape as the box culvert top plate and the top corner, and along the top of the backfilling soil shaped, 10cm thick C15 box culvert top plate cushion concrete is poured as the base surface and inner mold for the construction of the top of the box culvert; 7. Then the box culvert top plate and the top corner reinforcement binding, water stop installation and outside formwork setting are carried out, and finally the box culvert top plate concrete pouring is carried out.

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