Ductile cast iron jacking pipe outer wall concrete layer jolt ramming device and method

Abstract

The invention discloses a nodular cast iron jacking pipe outer wall concrete layer jolt ramming device and method, and belongs to the technical field of nodular cast iron jacking pipe outer wall concrete layer jolt ramming. The nodular cast iron jacking pipe outer wall concrete layer jolt ramming device comprises a first mold, a second mold and a third mold, bases are arranged on the circumferential faces of the first mold, the second mold and the third mold, and a pneumatic vibrator is arranged on one side of each base. In order to solve the problem that the jolt ramming efficiency of a concrete protective layer of a nodular cast iron jacking pipe is low, a plurality of bases are welded to the circumferential face of a nodular cast iron jacking pipe pouring mold from bottom to top, pneumatic vibrators are installed on the bases before pouring, and the pneumatic vibrators are sequentially started from bottom to top during pouring; the number and the distribution mode of the pneumatic vibrators can be changed according to the size of the nodular cast iron jacking pipe, it is guaranteed that a good jolt ramming effect can be obtained at different positions in a concrete layer, and the concrete jolt ramming efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of vibration compaction of concrete layer on the outer wall of ductile iron jacking pipe, in particular to a device and method for vibration compaction of concrete layer on the outer wall of ductile iron jacking pipe. Background Art

[0002] An important application scenario of ductile iron pipes is trenchless technology. Trenchless construction technology is the laying and updating of ductile iron pipelines without excavating the surface. Trenchless construction has the characteristics of not damaging the environment and not affecting traffic. It can be used to construct various underground pipelines in areas where excavation construction cannot be implemented, such as busy urban areas, historical sites protection areas, crop and vegetation protection areas, and crossing highways, railways, buildings, rivers and lakes. Thanks to my country's rapid economic development and infrastructure construction, trenchless technology has developed rapidly in China in recent years. Common trenchless construction technologies are mainly divided into traction method and jacking method.

[0003] Pipe jacking technology is a type of trenchless technology. The pipe diameter is generally DN600-DN2600. The common ductile iron pipe jacking is to use a special molding mold to cast a concrete protective layer on the outer wall of the cast pipe, and then steam cure the concrete layer to completely solidify and generate strength. Concrete is mainly mixed with raw materials such as cement, sand, gravel and admixtures. In order to make the concrete layer obtain better strength and wear resistance, the anti-corrosion coating on the outside of the ductile iron pipe can be effectively protected from damage during the jacking construction. When pouring ductile iron pipe jacking concrete, a vibration operation will be used to increase the density of the concrete layer. The purpose of the vibration operation is to fully fill the concrete in the molding mold, effectively remove the internal gas, and finally form a dense structure.

[0004] The pouring of the concrete protective layer of the ductile iron pipe jacking is to assemble the ductile iron pipe and the mold in advance, and then use the crane and the pipe turning machine to make the pipe stand vertically in the pouring pit. At this time, the socket is at the bottom, and the bottom support of the mold clamps the socket to ensure the seal, and the spigot is at the top, which is convenient for the installation of the pouring cap. The pouring cap is composed of a receiving hopper and a lower hopper. During pouring, the concrete falls on the lower hopper, and then flows into the receiving hopper along the inner wall of the lower hopper, and then flows into the cavity between the mold and the pipe. While pouring, there is a vibration requirement, the purpose is to expel the bubbles in the concrete layer and make the whole structure dense to obtain good strength. The conventional vibration process is generally through a vibration table or a vibration rod. When using a vibration table for vibration, due to the large span of the jacking pipe diameter, the selection and capacity requirements of the vibration table are relatively large, and there is often a situation where a big horse pulls a small cart. At the same time, due to the continuous production of the jacking pipe Due to the continuity requirement, there are often a large number of pouring pits, which will result in the need for multiple vibrators, or the pipe of a single vibrator has to be lifted back and forth before and after pouring and compaction. Therefore, although the use of a vibrating table to vibrate when pouring the concrete layer of ductile iron pipe jacking can achieve a good compaction effect, it has the disadvantages of large investment, high cost or efficiency impact. When using a vibrating rod to vibrate, since the thickness of the concrete protective layer of the ductile iron pipe jacking is relatively small, between 40 mm and 120 mm, and there is a steel mesh skeleton in the middle, the vibrating rod has a small operating space and is easily affected by the steel skeleton. At the same time, due to the large effective length span of the ductile iron pipe jacking, the common ones are 2m, 3m, 4, 5m, and 6m. Conventional vibrating rods cannot reach the bottom concrete, and the specially lengthened vibrating rods can meet the requirements of the intensity depth, but the vibration effect of the tip is also greatly weakened.

[0005] However, due to the large span, thin concrete thickness and great depth, the vibration table has high requirements on the foundation and occupies a large area. Either it is costly to invest in multiple units at one time, or it is troublesome to invest in one unit and frequently lift the pipe for casting. When using a vibration rod, the bottom cannot be vibrated due to the small vibration space and large depth, which affects the overall compaction effect. As a result, the existing method of using a vibration table or a vibration rod has the problem of low compaction efficiency of the concrete protective layer of the ductile iron jacking pipe. Therefore, it does not meet the existing needs. In this regard, the present application proposes a device and method for compacting the concrete layer on the outer wall of a ductile iron jacking pipe. Summary of the invention

[0006] The purpose of the present invention is to provide a device and method for compacting the concrete layer on the outer wall of a ductile iron jacking pipe. A base is welded to the circumferential surface of a ductile iron jacking pipe casting mold, and the base is provided with several parts from bottom to top. A pneumatic vibrator is then installed on the base. When pouring concrete, the pneumatic vibrators are turned on in sequence from bottom to top, and the vibrators are continuously vibrated until water oozes out of the concrete surface after the pouring is completed. The pneumatic vibrators can be used repeatedly, thereby reducing costs, improving concrete compaction efficiency, and solving the problems in the prior art.

[0007] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a device for compacting the concrete layer on the outer wall of a ductile iron jacking pipe, comprising a base, and also comprising a first mold, a second mold and a third mold, wherein the first mold, the second mold and the third mold are hollow cylindrical structures, and the circumferential surfaces of the three are all provided with bases, and a pneumatic vibrator is provided on one side of the base, the circumferential surface of the first mold is provided with at least eight bases, the circumferential surface of the second mold is provided with at least sixteen bases, and the circumferential surface of the third mold is provided with at least twenty bases, and the first mold, the second mold and the third mold are respectively provided with a first jacking pipe, a second jacking pipe and a third jacking pipe inside.

[0008] Preferably, the eight bases are all welded to the circumferential surface of the first mold, and the eight bases are divided into four layers from upward, with two bases in each layer, and the layers are parallel to each other. The two bases in each layer form an angle of 180° with the first top pipe as the center. The first layer is 0.4m away from the bottom of the first mold, the second layer is 2m away from the first layer, the third layer is 0.8m away from the second layer, and the fourth layer is 2m away from the third layer.

[0009] Preferably, the sixteen bases are all welded to the circumferential surface of the second mold, and the sixteen bases are divided into four layers from upward, with four bases in each layer, and the layers are parallel to each other. Any two adjacent bases among the four bases in each layer form a 90° angle with the second top pipe as the center. The first layer is 0.4m away from the bottom of the second mold, the second layer is 2m away from the first layer, the third layer is 0.8m away from the second layer, and the fourth layer is 2m away from the third layer.

[0010] Preferably, the twenty bases are welded to the circumferential surface of the third mold, and the twenty bases are divided into five layers from bottom to top, with four bases in each layer, and the layers are parallel to each other. Any two adjacent bases in the four bases in each layer form an angle of 90° with the third top pipe as the center. The first layer is 0.4m away from the bottom of the third mold, the second layer is 1.2m away from the first layer, the third layer is 1.2m away from the second layer, the fourth layer is 1.2m away from the third layer, and the fifth layer is 1.2m away from the fourth layer.

[0011] Preferably, the first jack pipe, the second jack pipe and the third jack pipe are all made of ductile iron, the minimum size and maximum size of the first jack pipe are DN600 and DN1200 respectively, the minimum size and maximum size of the second jack pipe are DN1400 and DN1800 respectively, and the minimum size and maximum size of the third jack pipe are DN2000 and DN2600 respectively.

[0012] Preferably, a positioning plate is provided on the side of the base, a fixing plate is provided on the side of the pneumatic vibrator, the fixing plate is located between the two positioning plates, the fixing plate and the base are connected by fixing screws, a buckle is provided on one side of the fixing plate, and the buckle and the base are connected by a limit screw.

[0013] A method for compacting the concrete layer on the outer wall of a ductile iron top pipe is implemented based on a device for compacting the concrete layer on the outer wall of a ductile iron top pipe, and comprises the following steps:

[0014] S1. Weld eight bases on the circumferential surface of the first mold, weld sixteen bases on the circumferential surface of the second mold, and weld twenty bases on the circumferential surface of the third mold;

[0015] S2, placing the first mold upright inside the curing pit, and installing a pneumatic vibrator on the base;

[0016] S3, connecting the compressed air pipeline to the pneumatic vibrator, pouring concrete between the first mold and the first jacking pipe, and starting the pneumatic vibrator to perform a vibration compaction operation;

[0017] S4, after the compaction operation is completed, a concrete curing operation is performed until a concrete protective layer is formed on the surface of the first mold. After the concrete curing operation is completed, the connection between the compressed air pipeline and the pneumatic vibrator is disconnected, and the pneumatic vibrator is removed from the base;

[0018] S5, repeating S2, S3 and S4 in sequence for the second mold and the third mold respectively until concrete protective layers are formed on the surfaces of the second mold and the third mold respectively.

[0019] Preferably, the step of vibrating the first mold in S3 comprises:

[0020] S301: pour concrete between the first mold and the first jacking pipe through the feeding hopper, and start the pneumatic vibrator of the first layer at the same time. When the concrete height is 0.4m, start the pneumatic vibrator of the second layer. When the concrete height is 2.4m, start the pneumatic vibrator of the third layer. When the concrete height is 3.4m, start the pneumatic vibrator of the fourth layer. The exciting force of the pneumatic vibrator is 40KN, and the vibration is 1.6mm.

[0021] S302: After pouring is completed, continue vibrating for five minutes until water seeps out of the concrete surface, and then turn off all pneumatic vibrators.

[0022] Preferably, the step of vibrating the second mold in S3 is the same as that of the first mold, and the step of vibrating the third mold includes:

[0023] S311: pour concrete between the third mold and the third jacking pipe through the feeding hopper, and start the pneumatic vibrator of the first layer at the same time. When the concrete height is 0.4m, start the pneumatic vibrator of the second layer. When the concrete height is 1.6m, start the pneumatic vibrator of the third layer. When the concrete height is 2.8m, start the pneumatic vibrator of the fourth layer. When the concrete height is 4m, start the pneumatic vibrator of the fifth layer. The exciting force of the pneumatic vibrator is 40KN, and the vibration is 1.6mm.

[0024] S312: After pouring, continue vibrating for five minutes until water seeps out of the concrete surface, then turn off all pneumatic vibrators.

[0025] Preferably, the concrete curing operation steps of the first mold, the second mold and the third mold in S4 are the same, and the concrete curing operation steps of the first mold include:

[0026] S401: After the upper end of the first mold is sealed, steam is transported from the lower end of the first mold to the inside through a pipeline, and the internal temperature is kept at least 70° for nine hours;

[0027] S402: after removing the first mold and repairing the concrete protective layer on the surface of the first jacking pipe, the concrete protective layer is covered with a tarpaulin, and steam is transported to the concrete protective layer through a pipeline until the internal temperature reaches at least 70°, and then the temperature is kept for nine hours;

[0028] S403: Use a concrete rebound tester to test the rebound strength of the concrete cover. It meets the standard when it reaches at least 32Mp.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The present invention welds a plurality of bases on the circumferential surface of a ductile iron jacking pipe casting mold. The number of layers and the number of bases on each layer are set according to the size of the ductile iron jacking pipe. Before casting, a pneumatic vibrator is installed on the base. When casting concrete, the pneumatic vibrator of each layer is turned on from bottom to top in sequence, and the pneumatic vibrator is continuously vibrated until water oozes out of the surface of the concrete after the casting is completed. The pneumatic vibrator can be repeatedly used on different molds, the investment in production equipment is small, and only simple maintenance is required on a daily basis, thereby reducing costs.

[0031] 2. The present invention connects the base and the pneumatic vibrator through a fixing screw, the fixing screw is located between the buckle and the base, and then connects the buckle and the base through a limit screw, thereby reducing the risk of the fixing screw falling off and improving the safety of the compaction operation. At the same time, according to the different sizes of ductile iron jacking pipes, the number and distribution of pneumatic vibrators are changed in a targeted manner to ensure that different positions in the concrete layer can obtain a good compaction effect, improve the concrete compaction efficiency, and ensure the strength of the subsequent concrete layer after maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the partial structure of the first mold of the present invention;

[0033] Figure 2 It is a schematic diagram of the partial structure of the second mold of the present invention;

[0034] Figure 3It is a schematic diagram of the partial structure of the third mold of the present invention;

[0035] Figure 4 It is a schematic diagram of the local structure of the buckle of the present invention;

[0036] Figure 5 It is a schematic diagram of the partial structure of the pneumatic vibrator of the present invention.

[0037] In the figure: 1, pneumatic vibrator; 101, fixing plate; 102, fixing screw; 2, base; 201, positioning plate; 202, groove; 3, buckle; 301, limit screw; 4, first jacking tube; 401, first mold; 5, second jacking tube; 501, second mold; 6, third jacking tube; 601, third mold. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] To solve the problem of low compaction efficiency of the concrete cover of ductile iron pipe jacking, please refer to Figure 1-5 , this embodiment provides the following technical solutions:

[0040] A device for compacting the concrete layer on the outer wall of a ductile iron jacking pipe comprises a base 2, and also comprises a first mold 401, a second mold 501 and a third mold 601. The first mold 401, the second mold 501 and the third mold 601 are hollow cylindrical structures. The circumferential surfaces of the three are all provided with a base 2, and a pneumatic vibrator 1 is provided on one side of the base 2. The circumferential surface of the first mold 401 is provided with at least eight bases 2, the circumferential surface of the second mold 501 is provided with at least sixteen bases 2, and the circumferential surface of the third mold 601 is provided with at least twenty bases 2. The first mold 401, the second mold 501 and the third mold 601 are respectively provided with a first jacking pipe 4, a second jacking pipe 5 and a third jacking pipe 6.

[0041] Eight bases 2 are welded to the circumferential surface of the first mold 401, and the eight bases 2 are divided into four layers from upward, with two bases in each layer, and the layers are parallel to each other. The two bases 2 in each layer form an angle of 180° with the first top tube 4 as the center. The first layer is 0.4m away from the bottom of the first mold 401, the second layer is 2m away from the first layer, the third layer is 0.8m away from the second layer, and the fourth layer is 2m away from the third layer; sixteen bases 2 are welded to the circumferential surface of the second mold 501, and the sixteen bases 2 are divided into four layers from upward, with four bases in each layer, and the layers are parallel to each other. Any two adjacent bases 2 in the four bases 2 in each layer form an angle of 90° with the second top tube 5 as the center. The first layer is 0.4m away from the bottom of the second mold 501, the second layer is 2m away from the first layer, the third layer is 0.8m away from the second layer, and the fourth layer is 2m away from the third layer; twenty Each base 2 is welded to the circumferential surface of the third mold 601. The twenty bases 2 are divided into five layers from bottom to top, with four bases in each layer. The layers are parallel to each other. Any two adjacent bases 2 in the four bases 2 in each layer form an angle of 90° with the third jacking pipe 6 as the center. The first layer is 0.4m away from the bottom of the third mold 601, the second layer is 1.2m away from the first layer, the third layer is 1.2m away from the second layer, the fourth layer is 1.2m away from the third layer, and the fifth layer is 1.2m away from the fourth layer. The first jacking pipe 4, the second jacking pipe 5 and the third jacking pipe 6 are all made of ductile iron. The minimum and maximum sizes of the first jacking pipe 4 are DN600 and DN1200 respectively, the minimum and maximum sizes of the second jacking pipe 5 are DN1400 and DN1800 respectively, and the minimum and maximum sizes of the third jacking pipe 6 are DN2000 and DN2600 respectively.

[0042] Specifically, the welding areas between the first mold 401, the second mold 501 and the third mold 601 and the base 2 need to be thickened by 5mm-10mm, and the area of ​​the thickened area needs to be slightly larger than the base 2. Before pouring, the pneumatic vibrator 1 is installed on the base 2. When pouring concrete, the pneumatic vibrator 1 of each layer is turned on from bottom to top, and the vibration is continued after the pouring until water oozes from the surface of the concrete. The pneumatic vibrator 1 can be repeatedly used on different molds, and the investment in production equipment is small. At the same time, only simple maintenance is required on a daily basis, which further reduces the cost.

[0043] A positioning plate 201 is provided on the side of the base 2, and a fixing plate 101 is provided on the side of the pneumatic vibrator 1. The fixing plate 101 is located between the two positioning plates 201. The fixing plate 101 is connected to the base 2 by a fixing screw 102. A buckle 3 is provided on one side of the fixing plate 101. The fixing screw 102 is located between the buckle 3 and the base 2. The buckle 3 and the base 2 are connected by a limit screw 301, which can reduce the risk of the fixing screw 102 falling off and improve the safety of the compaction operation. At the same time, according to the different sizes of ductile iron jacking pipes, the number and distribution of pneumatic vibrators 1 are changed in a targeted manner to ensure that different positions in the concrete layer can obtain good compaction effects, improve the concrete compaction efficiency, and ensure the strength of the subsequent concrete layer after maintenance.

[0044] A method for compacting the concrete layer on the outer wall of a ductile iron top pipe is implemented based on a device for compacting the concrete layer on the outer wall of a ductile iron top pipe, and comprises the following steps:

[0045] S1, welding eight bases 2 on the circumferential surface of the first mold 401, welding sixteen bases 2 on the circumferential surface of the second mold 501, and welding twenty bases 2 on the circumferential surface of the third mold 601;

[0046] S2, erecting the first mold 401 inside the curing pit, and installing the pneumatic vibrator 1 on the base 2;

[0047] S3, connecting the compressed air pipeline to the pneumatic vibrator 1, pouring concrete between the first mold 401 and the first jacking pipe 4, and starting the pneumatic vibrator 1 to perform a vibration operation;

[0048] S4, after the compaction operation is completed, the concrete curing operation is performed until a concrete protective layer is formed on the surface of the first mold 401. After the concrete curing operation is completed, the connection between the compressed air pipeline and the pneumatic vibrator 1 is disconnected, and the pneumatic vibrator 1 is removed from the base 2;

[0049] S5. Repeat S2, S3 and S4 in sequence for the second mold 501 and the third mold 601 until concrete protective layers are formed on the surfaces of the second mold 501 and the third mold 601 respectively.

[0050] Specifically, the steps of performing the vibration compaction operation on the first mold 401 in S3 include:

[0051] S301: pour concrete between the first mold 401 and the first jacking pipe 4 through the feeding hopper, and start the pneumatic vibrator 1 of the first layer at the same time. When the concrete height is 0.4m, start the pneumatic vibrator 1 of the second layer. When the concrete height is 2.4m, start the pneumatic vibrator 1 of the third layer. When the concrete height is 3.4m, start the pneumatic vibrator 1 of the fourth layer. The exciting force of the pneumatic vibrator 1 is 40KN, and the vibration is 1.6mm.

[0052] S302: After pouring is completed, vibration is continued for five minutes until water seeps out of the concrete surface, and then all pneumatic vibrators 1 are turned off.

[0053] Specifically, the steps of the second mold 501 performing the compaction operation in S3 are the same as those of the first mold 401, and the steps of the third mold 601 performing the compaction operation include:

[0054] S311: pour concrete between the third mold 601 and the third jacking pipe 6 through the feeding hopper, and start the pneumatic vibrator 1 of the first layer at the same time. When the concrete height is 0.4m, start the pneumatic vibrator 1 of the second layer. When the concrete height is 1.6m, start the pneumatic vibrator 1 of the third layer. When the concrete height is 2.8m, start the pneumatic vibrator 1 of the fourth layer. When the concrete height is 4m, start the pneumatic vibrator 1 of the fifth layer. The exciting force of the pneumatic vibrator 1 is 40KN, and the vibration is 1.6mm.

[0055] S312: After pouring is completed, vibration is continued for five minutes until water seeps out of the concrete surface, and then all pneumatic vibrators 1 are turned off.

[0056] Specifically, the concrete curing operation steps of the first mold 401, the second mold 501 and the third mold 601 in S4 are the same, and the concrete curing operation steps of the first mold 401 include:

[0057] S401: After the upper end of the first mold 401 is sealed, steam is transported from the lower end of the first mold 401 to the inside through a pipeline, and the internal temperature is kept at least 70° for nine hours;

[0058] S402: After removing the first mold 401 and repairing the concrete protective layer on the surface of the first jacking pipe 4, the concrete protective layer is covered with a tarpaulin, and steam is transported to the concrete protective layer through a pipeline until the internal temperature reaches at least 70°, and then the temperature is kept for nine hours;

[0059] S403: Use a concrete rebound tester to test the rebound strength of the concrete cover. It meets the standard when it reaches at least 32Mp.

[0060] Working principle: a base 2 is welded on the circumferential surface of the ductile iron jacking pipe casting mold. The base 2 is provided with several parts from bottom to top. The pneumatic vibrator 1 is installed on the base 2 before casting. When pouring concrete, the pneumatic vibrator 1 is turned on from bottom to top in sequence. After the pouring, the pneumatic vibrator 1 is continuously vibrated until water oozes out of the concrete surface. The pneumatic vibrator 1 can be used repeatedly, thereby reducing the cost. At the same time, according to the different sizes of ductile iron jacking pipes, the number and distribution of the pneumatic vibrators 1 are changed in a targeted manner to ensure that different positions in the concrete layer can obtain good compaction effects, thereby improving the concrete compaction efficiency.

[0061] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0062] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for compacting the concrete layer on the outer wall of a ductile iron top pipe, comprising a base (2), characterized in that: The invention also comprises a first mould (401), a second mould (501) and a third mould (601), wherein the first mould (401), the second mould (501) and the third mould (601) are hollow cylindrical structures, the circumferential surfaces of the three moulds are all provided with bases (2), one side of the bases (2) is provided with a pneumatic vibrator (1), the circumferential surface of the first mould (401) is provided with at least eight bases (2), the circumferential surface of the second mould (501) is provided with at least sixteen bases (2), the circumferential surface of the third mould (601) is provided with at least twenty bases (2), and the first mould (401), the second mould (501) and the third mould (601) are provided with a first top pipe (4), a second top pipe (5) and a third top pipe (6) respectively inside.

2. A device for vibrating and compacting the concrete layer on the outer wall of a ductile iron top pipe according to claim 1, characterized in that: The eight bases (2) are all welded to the circumferential surface of the first mold (401). The eight bases (2) are divided into four layers from upward, with two bases in each layer. The layers are parallel to each other. The two bases (2) in each layer form an angle of 180° with the first top pipe (4) as the center. The first layer is 0.4 m away from the bottom of the first mold (401), the second layer is 2 m away from the first layer, the third layer is 0.8 m away from the second layer, and the fourth layer is 2 m away from the third layer.

3. The device for vibrating and compacting the concrete layer on the outer wall of a ductile iron top pipe according to claim 1, characterized in that: The sixteen bases (2) are all welded to the circumferential surface of the second mold (501). The sixteen bases (2) are divided into four layers from top to bottom, with four bases in each layer. The layers are parallel to each other. Any two adjacent bases (2) in the four bases (2) in each layer form an angle of 90° with the second top pipe (5) as the center. The first layer is 0.4 m away from the bottom of the second mold (501), the second layer is 2 m away from the first layer, the third layer is 0.8 m away from the second layer, and the fourth layer is 2 m away from the third layer.

4. A device for compacting the concrete layer on the outer wall of a ductile iron top pipe according to claim 1, characterized in that: The twenty bases (2) are all welded to the circumferential surface of the third mold (601). The twenty bases (2) are divided into five layers from bottom to top, with four bases in each layer. The layers are parallel to each other. Any two adjacent bases (2) in the four bases (2) in each layer form an angle of 90° with the third top pipe (6) as the center. The first layer is 0.4 m away from the bottom of the third mold (601), the second layer is 1.2 m away from the first layer, the third layer is 1.2 m away from the second layer, the fourth layer is 1.2 m away from the third layer, and the fifth layer is 1.2 m away from the fourth layer.

5. The device for vibrating and compacting the concrete layer on the outer wall of a ductile iron top pipe according to claim 1, characterized in that: The first jack pipe (4), the second jack pipe (5) and the third jack pipe (6) are all made of ductile iron. The minimum size and maximum size of the first jack pipe (4) are DN600 and DN1200 respectively, the minimum size and maximum size of the second jack pipe (5) are DN1400 and DN1800 respectively, and the minimum size and maximum size of the third jack pipe (6) are DN2000 and DN2600 respectively.

6. The device for compacting the concrete layer on the outer wall of a ductile iron top pipe according to claim 1, characterized in that: A positioning plate (201) is provided on the side of the base (2), a fixing plate (101) is provided on the side of the pneumatic vibrator (1), the fixing plate (101) is located between the two positioning plates (201), the fixing plate (101) and the base (2) are connected via fixing screws (102), a buckle (3) is provided on one side of the fixing plate (101), and the buckle (3) and the base (2) are connected via limiting screws (301).

7. A method for compacting the concrete layer on the outer wall of a ductile iron jacking pipe, which is implemented based on the device for compacting the concrete layer on the outer wall of a ductile iron jacking pipe according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1, welding eight bases (2) on the circumferential surface of the first mold (401), welding sixteen bases (2) on the circumferential surface of the second mold (501), and welding twenty bases (2) on the circumferential surface of the third mold (601); S2, placing the first mold (401) upright inside the curing pit, and installing a pneumatic vibrator (1) on the base (2); S3, connecting the compressed air pipeline to the pneumatic vibrator (1), pouring concrete between the first mold (401) and the first jacking pipe (4), and starting the pneumatic vibrator (1) to perform a vibration compaction operation; S4, after the compaction operation is completed, a concrete curing operation is performed until a concrete protective layer is formed on the surface of the first mold (401). After the concrete curing operation is completed, the connection between the compressed air pipeline and the pneumatic vibrator (1) is disconnected, and the pneumatic vibrator (1) is removed from the base (2); S5. Repeat S2, S3 and S4 in sequence for the second mold (501) and the third mold (601) respectively until concrete protective layers are formed on the surfaces of the second mold (501) and the third mold (601).

8. A method for vibrating the outer wall concrete layer of a ductile iron top pipe according to claim 7, characterized in that: The step of performing the vibrating operation on the first mold (401) in S3 comprises: S301: concrete is poured between the first mold (401) and the first jacking pipe (4) through the feeding hopper, and the pneumatic vibrator (1) of the first layer is turned on at the same time. When the concrete height is 0.4m, the pneumatic vibrator (1) of the second layer is turned on. When the concrete height is 2.4m, the pneumatic vibrator (1) of the third layer is turned on. When the concrete height is 3.4m, the pneumatic vibrator (1) of the fourth layer is turned on. The exciting force of the pneumatic vibrator (1) is 40KN, and the vibration is 1.6mm. S302: After pouring is completed, vibration is continued for five minutes until water seeps out of the concrete surface, and then all pneumatic vibrators (1) are turned off.

9. A method for vibrating and compacting the concrete layer on the outer wall of a ductile iron top pipe according to claim 7, characterized in that: The steps of vibrating and compacting the second mold (501) in S3 are the same as those of the first mold (401), and the steps of vibrating and compacting the third mold (601) include: S311: concrete is poured between the third mold (601) and the third jacking pipe (6) through the feeding hopper, and the pneumatic vibrator (1) of the first layer is turned on at the same time. When the concrete height is 0.4m, the pneumatic vibrator (1) of the second layer is turned on. When the concrete height is 1.6m, the pneumatic vibrator (1) of the third layer is turned on. When the concrete height is 2.8m, the pneumatic vibrator (1) of the fourth layer is turned on. When the concrete height is 4m, the pneumatic vibrator (1) of the fifth layer is turned on. The exciting force of the pneumatic vibrator (1) is 40KN, and the vibration is 1.6mm. S312: After pouring is completed, vibration is continued for five minutes until water seeps out of the concrete surface, and then all pneumatic vibrators (1) are turned off.

10. A method for vibrating the outer wall concrete layer of a ductile iron top pipe according to claim 7, characterized in that: The concrete curing operation steps of the first mold (401), the second mold (501) and the third mold (601) in S4 are the same, and the concrete curing operation steps of the first mold (401) include: S401: After the upper end of the first mold (401) is sealed, steam is transported from the lower end of the first mold (401) to the inside through a pipeline, and the internal temperature is kept at least 70° for nine hours; S402: after removing the first mold (401) and repairing the concrete protective layer on the surface of the first jacking pipe (4), the concrete protective layer is covered with a tarpaulin, and steam is transported to the concrete protective layer through a pipeline until the internal temperature reaches at least 70°, and then the temperature is kept for nine hours; S403: Use a concrete rebound tester to test the rebound strength of the concrete cover. It meets the standard when it reaches at least 32Mp.

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