Underwater connection method of prefabricated box culvert and existing underground structure

Abstract

The present invention relates to the technical field of underground structure engineering, and specifically discloses a method for underwater connection between a prefabricated box culvert and an existing underground structure, including setting a temporary sealing device at the end of the prefabricated box culvert, setting an end sealing door in the working well at the end of the underground structure and sealing it, breaking the existing enclosure structure, transporting the prefabricated box culvert to the docking starting point and advancing it until the temporary sealing device is tightly fitted with the early ring beam of the cave entrance, grouting is performed using a grouting pipe, the water in the sealing chamber is drained and the anti-flooding door and the end sealing door are removed, and a pressure test and leak detection test is performed on the joint between the prefabricated box culvert corbel and the early ring beam of the cave entrance. After the pressure test and leak detection test are qualified, the temporary sealing device is removed, a circle of reinforced concrete ring frame beams are cast in place at the cave entrance, the prefabricated box culvert is connected to the underground structure, and the underwater foundation trench is backfilled. The present invention is conducive to implementing the connection between the prefabricated box culvert and the existing underground structure in a highly permeable stratum with abundant groundwater, reducing engineering risks and ensuring engineering quality.

Description

Technical Field

[0001] The invention relates to the technical field of underground structure engineering, and in particular to an underwater connection method of a prefabricated box culvert and an existing underground structure. Background Art

[0002] At present, the conventional method of connecting reinforced concrete pipe corridors with existing underground structures is to reserve steel connectors or steel slings in the beams and slabs of the existing underground structures, and cast them on site as a whole with the beams and slabs of the ends of the reinforced concrete pipe corridors. This construction method can ensure that the reinforced concrete pipe corridors have a certain strength and durability after being connected to the existing underground structures in ordinary strata. However, in highly permeable strata with abundant groundwater, the scheme of connecting the cast-in-place concrete pipe corridors with existing underground structures by open excavation will have problems such as high engineering risks and difficulty in ensuring quality. Summary of the invention

[0003] The purpose of the present invention is to provide an underwater connection method for a prefabricated box culvert and an existing underground structure, so as to solve the problems of high engineering risk and difficult quality assurance when using the existing connection method in a highly permeable stratum with abundant groundwater.

[0004] In order to solve the above technical problems, the present invention provides a method for underwater connection between a prefabricated box culvert and an existing underground structure, which is characterized by comprising the following steps:

[0005] S1. A temporary sealing device is provided at the end of the prefabricated box culvert, wherein the temporary sealing device comprises a stainless steel plate and a stainless steel wire brush. The stainless steel plate is placed obliquely, one end of which is installed on the end of the prefabricated box culvert, and the other end is provided with the stainless steel wire brush. A grouting pipe is provided at the end of the prefabricated box culvert, and an end sealing door is provided inside the prefabricated box culvert;

[0006] S2. Excavate the foundation trench underwater within the route range of the underground pipe gallery, transport the prefabricated box culvert to the docking point between the working well at the end of the underground structure and the prefabricated box culvert, cast the preliminary ring beam at the opening of the working well at the end of the underground structure, and install the flood prevention door in the working well at the end of the underground structure;

[0007] S3. Remove the external enclosure structure of the underground structure, push the prefabricated box culvert toward the underground structure, and make the stainless steel wire brush of the temporary sealing device of the prefabricated box culvert end contact and fit with the previous ring beam at the opening of the working well of the underground structure end. When the end of the prefabricated box culvert completely enters the working well of the underground structure end and the corbel of the prefabricated box culvert fits tightly with the previous ring beam of the underground structure, stop pushing, and form a sealed chamber between the flood prevention door and the end sealing door;

[0008] S4. Use the grouting pipe to inject grout between the prefabricated box culvert corbel and the enclosure structure, and between the early ring beam and the enclosure structure, drain the water in the sealed chamber, and remove the flood prevention door and end sealing door;

[0009] S5. Perform a pressure test and leak test on the joint between the prefabricated box culvert corbel and the previous ring beam. After the pressure test and leak test are passed, remove the temporary sealing device at the end of the prefabricated box culvert, cast a circle of reinforced concrete ring frame beams between the previous ring beam at the end of the working well of the underground structure and the end of the prefabricated box culvert, and the connection between the prefabricated box culvert and the end of the underground structure is completed;

[0010] S6. Carry out backfilling operations within the underwater foundation trench backfilling range.

[0011] Preferably, in step S1, the temporary sealing devices are multiple groups evenly arranged along the advancing direction.

[0012] Preferably, in step S1, the stainless steel plate is tilted backwards, and a waterproof rubber plate is provided on the front side of the stainless steel plate.

[0013] Preferably, in step S2, sponge rubber sealing material is filled at the four corners of the working shaft opening at the end of the underground structure, and the sponge rubber sealing material fits tightly with the prefabricated box culvert and the underground structure.

[0014] Preferably, in step S2, a temporary steel support is set up at the cast-in-place preliminary ring beam at the entrance of the underground structure.

[0015] Preferably, in step S2, a steel track is laid at the bottom of the underwater foundation trench, and the prefabricated box culvert is transported to the starting point of the connection between the working well at the end of the underground structure and the prefabricated box culvert on the steel track. In step S3, the prefabricated box culvert is pushed toward the direction of the underground structure by a jack in conjunction with the steel track.

[0016] Preferably, in step S1, a telescopic limit rod is provided at the front end of the prefabricated box culvert end. In step S3, after the prefabricated box culvert end completely enters the working well of the end of the underground structure and the prefabricated box culvert corbel fits tightly with the early ring beam of the underground structure, the telescopic limit rod is extended and connected to the flood prevention door, and the jack is kept not released.

[0017] Preferably, in step S3, during the advancement of the prefabricated box culvert, grouting is injected into the cavity on the rear side of the stainless steel plate through a grouting pipe.

[0018] Preferably, in step S5, if the pressure test and leak detection test fails, the leaking point is sealed by grouting, and the pressure test and leak detection test is repeated until there is no leaking point and the pressure test and leak detection test passes.

[0019] Preferably, in step S6, the soil above and on the sides of the pipe gallery is backfilled to level the site.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] A temporary sealing device is used to temporarily block groundwater. During the process of the prefabricated box culvert being pushed into the end of the underground structure, the stainless steel wire brush contacts and deforms with the preliminary ring beam of the well hole at the end of the underground structure, achieving a shock-absorbing effect. The stainless steel plate is bent under the action of water pressure by grouting, and the stainless steel wire brush will fit closely with the preliminary ring beam of the hole, thereby enhancing the temporary sealing effect. The present invention is conducive to the connection between the prefabricated box culvert and the existing underground structure in a highly permeable stratum with abundant groundwater, reducing engineering risks and ensuring engineering quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of preliminary preparations for jacking a prefabricated box culvert to an end of an underground structure in a method for underwater connection of a prefabricated box culvert to an existing underground structure according to an embodiment of the present invention;

[0023] Figure 2 for Figure 1 AA section view;

[0024] Figure 3 A schematic diagram of a method for underwater connection of a prefabricated box culvert and an existing underground structure in accordance with an embodiment of the present invention, wherein the prefabricated box culvert is pushed toward the end of the underground structure;

[0025] Figure 4 for Figure 3 BB section view;

[0026] Figure 5 A schematic diagram of a cast-in-place reinforced concrete ring frame beam at an end opening of an underground structure in a method for underwater connection between a prefabricated box culvert and an existing underground structure according to an embodiment of the present invention;

[0027] Figure 6 for Figure 5 CC section view of ;

[0028] Figure 7 A schematic diagram of three sets of temporary sealing devices used in a method for underwater connection between a prefabricated box culvert and an existing underground structure according to an embodiment of the present invention;

[0029] Figure 8 Schematic diagram of four sets of temporary sealing devices used in a method for underwater connection between a prefabricated box culvert and an existing underground structure according to an embodiment of the present invention.

[0030] In the figure, 1. underground structure; 2. enclosure structure; 3. advance ring beam; 4. temporary steel support; 5. flood prevention door; 6. prefabricated box culvert; 7. jack; 8. end sealing door; 9. prefabricated box culvert corbel; 10. steel track; 11. groundwater level; 12. telescopic limit rod; 13. temporary sealed space; 14. reinforced concrete ring frame beam; 15. first set of temporary sealing device; 16. second set of temporary sealing device; 17. third set of temporary sealing device; 18. fourth set of temporary sealing device; 19. stainless steel wire brush; 20. stainless steel plate; 21. waterproof rubber sheet; 22. embedded steel plate; 23. grouting pipe; 24. bolt; 25. sponge rubber sealing material; 26. foundation trench backfill range; 27. sealing chamber; 28. temporary sealing device. DETAILED DESCRIPTION

[0031] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0034] like Figures 1 to 6 As shown, a method for underwater connection between a prefabricated box culvert and an existing underground structure according to an embodiment of the present invention comprises the following steps:

[0035] S1. A temporary sealing device 28 for temporarily blocking groundwater is provided at the end of the prefabricated box culvert 6. Figure 1As shown, the end is located at the front end of the corbel, and the temporary sealing device 28 of the end includes a stainless steel plate 20 and a stainless steel wire brush 19. The stainless steel plate 20 is placed obliquely, as shown in FIG. Figure 7 , 8 As shown, the stainless steel plate 20 is tilted backwards, and a waterproof rubber plate 21 can be provided on the front side to enhance the water-proof effect. One end of the stainless steel plate 20 is mounted on the embedded steel plate 22 at the end of the prefabricated box culvert 6 by bolts 24, and the other end is provided with a stainless steel wire brush 19.

[0036] The temporary sealing device 28 can be a plurality of groups evenly arranged along the propulsion direction. The more groups there are, the stronger the water pressure resistance is. Figure 7 As shown, there are three groups, namely, a first group of temporary sealing devices 15, a second group of temporary sealing devices 16 and a third group of temporary sealing devices 17. Figure 8 The arrangement shown is four groups, namely the first group of temporary sealing devices 15, the second group of temporary sealing devices 16, the third group of temporary sealing devices 17 and the fourth group of temporary sealing devices 18. A grouting pipe 23 is provided at the end of the prefabricated box culvert 6 to allow the grouting liquid to be filled into the rear side of the temporary sealing device 28.

[0037] A telescopic limit rod 12 for limiting the distance between the prefabricated box culvert 6 and the underground structure 1 is arranged at the front end of the prefabricated box culvert 6 , and end sealing doors 8 are arranged at both ends inside the prefabricated box culvert 6 .

[0038] The total longitudinal length of the three sets of temporary sealing devices 28 is 1000mm~2000mm, with 1500mm being the best. The length of the stainless steel wire brush 19 is 200~300mm, with 250mm being the best. The length of the prefabricated box culvert corbel 9 is 1~5m, with 2m being the best.

[0039] S2, such as Figure 1 , 2 As shown, underwater excavation of a foundation trench is carried out within the route range of the underground pipe gallery, the construction position is lower than the groundwater level 11, a steel track 10 is laid at the bottom of the foundation trench, and the length of the steel track 10 is designed according to actual needs, which is 5 m in this embodiment. The prefabricated box culvert 6 is transported to the starting point of the docking between the end working well of the underground structure 1 on the steel track 10 and the prefabricated box culvert 6, that is, the end of the underground structure 1 away from the steel track 10, by a floating method.

[0040] The four corners of the working well opening at the end of the underground structure 1 are filled with sponge rubber sealing material 25, and the sponge rubber sealing material 25 fits tightly with the prefabricated box culvert 6 and the existing underground structure 1 to enhance the sealing effect.

[0041] There is an existing enclosure structure 2 outside the working shaft at the end of the underground structure 1. An advance ring beam 3 is cast at the opening of the working shaft at the end of the underground structure 1, and a temporary steel support 4 is erected to ensure stability and strength at the opening of the working shaft.

[0042] A flood-proof door 5 is installed in the working shaft at the end of the underground structure 1 . At this time, a temporary sealed space 13 is formed between the flood-proof door 5 and the surrounding structure 2 .

[0043] S3, such as Figure 3 , 4 As shown, the external retaining structure 2 of the underground structure 1 is removed, and the prefabricated box culvert 6 is pushed toward the underground structure 1 through the jack 7 in cooperation with the steel track 10 on the foundation trench, and the stainless steel wire brush 19 of the temporary sealing device 28 at the end of the prefabricated box culvert 6 contacts and adheres to the early ring beam 3 at the working well opening at the end of the underground structure 1 and deforms, which plays a shock-absorbing role.

[0044] During the advancement of the prefabricated box culvert 6, grouting is injected into the cavity on the rear side of the stainless steel plate 20 through the grouting pipe 23 to enhance the supporting force of the stainless steel wire brush 19. The stainless steel plate 20 is bent by the pressure of the grouting liquid, and the stainless steel wire brush 19 will fit tightly against the preliminary ring beam 3 of the opening, thereby achieving a temporary sealing effect.

[0045] When the end of the prefabricated box culvert 6 completely enters the working well at the end of the underground structure 1 and the outer end of the prefabricated box culvert corbel 9 is tightly fitted with the outer end of the preliminary ring beam 3 of the opening of the underground structure 1, the advancement is stopped, and a sealing chamber 27 is formed between the flood-proof door 5 and the end sealing door 8. The telescopic limit rod 12 is extended and connected to the flood-proof door 5, and the jack 7 remains in a loosened state.

[0046] S4. Grouting is performed between the prefabricated box culvert corbel 9 and the enclosure structure 2 and between the preliminary ring beam 3 and the enclosure structure 2 through the innermost grouting pipe 23. The water in the sealing chamber 27 is pumped out with a water pump. After the water is drained, the flood prevention door 5 and the end sealing door 8 are removed.

[0047] S5. Perform a pressure test and leak detection on the joint between the prefabricated box culvert corbel 9 and the preliminary ring beam 3 of the opening of the underground structure 1. If the pressure test and leak detection test fails, the leaking point is sealed by grouting, and the pressure test and leak detection test is repeated until there is no leaking point. If the pressure test and leak detection test passes, the temporary sealing device 28 at the end of the prefabricated box culvert 6 is removed. Figure 5 , 6 As shown, a circle of reinforced concrete ring frame beam 14 is cast between the preliminary ring beam 3 at the end of the working shaft opening of the underground structure 1 and the end of the prefabricated box culvert 6. The size of the reinforced concrete ring frame beam 14 is designed according to actual needs. In this embodiment, it is 1500×700mm. The connection between the prefabricated box culvert 6 and the end of the underground structure 1 is completed.

[0048] S6. Carry out backfilling operation within the underwater foundation trench backfill range 26, and backfill the covering soil above and on the sides of the pipe gallery to level the site.

[0049] The temporary sealing device of the embodiment of the present invention plays a role in temporarily blocking groundwater. During the process of the prefabricated box culvert 6 being pushed forward to the end of the underground structure 1, the stainless steel wire brush 19 contacts and deforms with the preliminary ring beam 3 at the end of the well opening of the underground structure 1, which plays a role in shock absorption; at the same time, the stainless steel plate 20 bends under the action of water pressure, and the stainless steel wire brush 19 will fit tightly with the preliminary ring beam 3 at the opening, thereby enhancing the effect of temporary sealing. The embodiment of the present invention is conducive to the implementation of the scheme of connecting the prefabricated box culvert with the existing underground structure in a highly permeable stratum with abundant groundwater, reducing engineering risks and ensuring engineering quality.

[0050] The embodiments of the present invention are given for the purpose of illustration and description, and are not intended to be exhaustive or to limit the invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

Claims

1. A method for underwater connection between a prefabricated box culvert and an existing underground structure, characterized in that: The following steps are involved: S1. A temporary sealing device (28) is provided at the end of the prefabricated box culvert (6), wherein the temporary sealing device (28) comprises a stainless steel plate (20) and a stainless steel wire brush (19), wherein the stainless steel plate (20) is placed obliquely, one end of which is mounted on the end of the prefabricated box culvert (6), and the other end of which is provided with the stainless steel wire brush (19), a grouting pipe (23) is opened at the end of the prefabricated box culvert (6), and an end sealing door (8) is provided inside the prefabricated box culvert (6); S2, excavating a foundation trench underwater within the route range of the underground pipe gallery, transporting the prefabricated box culvert (6) to the docking start point between the working well at the end of the underground structure (1) and the prefabricated box culvert (6), casting an early ring beam (3) at the opening of the working well at the end of the underground structure (1), and installing a flood prevention door (5) in the working well at the end of the underground structure (1); S3, the outer enclosure structure (2) of the underground structure (1) is removed, and the prefabricated box culvert (6) is pushed toward the underground structure (1), the stainless steel wire brush (19) of the temporary sealing device (28) at the end of the prefabricated box culvert (6) is in contact with the preliminary ring beam (3) at the opening of the working well at the end of the underground structure (1), and grouting is injected into the cavity on the rear side of the stainless steel plate (20) through the grouting pipe (23). When the end of the prefabricated box culvert (6) completely enters the working well at the end of the underground structure (1) and the prefabricated box culvert corbel (9) is in close contact with the preliminary ring beam (3) of the underground structure (1), the advancement is stopped, and a sealing chamber (27) is formed between the flood prevention door (5) and the end sealing door (8); S4, grouting is performed between the prefabricated box culvert corbel (9) and the enclosure structure (2) and between the preliminary ring beam (3) and the enclosure structure (2) through the grouting pipe (23), the water in the sealing chamber (27) is drained, and the flood prevention door (5) and the end sealing door (8) are removed; S5, a pressure test and leak test is performed on the joint between the prefabricated box culvert corbel (9) and the preliminary ring beam (3). After the pressure test and leak test are passed, the temporary sealing device (28) at the end of the prefabricated box culvert (6) is removed, and a circle of reinforced concrete ring frame beam (14) is cast between the preliminary ring beam (3) at the end of the working well of the underground structure (1) and the end of the prefabricated box culvert (6). The connection between the prefabricated box culvert (6) and the end of the underground structure (1) is completed; S6. Perform backfilling operations within the underwater foundation trench backfilling range (26).

2. The underwater connection method of a prefabricated box culvert and an existing underground structure according to claim 1 is characterized in that: In the step S1, the temporary sealing devices (28) are multiple groups evenly arranged along the advancing direction.

3. The underwater connection method of a prefabricated box culvert and an existing underground structure according to claim 1 is characterized in that: In the step S1, the stainless steel plate (20) is tilted backwards, and a waterproof rubber plate (21) is provided on the front side of the stainless steel plate (20).

4. The underwater connection method of a prefabricated box culvert and an existing underground structure according to claim 1 is characterized in that: In step S2, the four corners of the working well opening at the end of the underground structure (1) are filled with a sponge rubber sealing material (25), and the sponge rubber sealing material (25) is tightly fitted to the prefabricated box culvert (6) and the underground structure (1).

5. The underwater connection method of a prefabricated box culvert and an existing underground structure according to claim 1 is characterized in that: In the step S2, a temporary steel support (4) is erected at the cast-in-place preliminary ring beam (3) at the opening of the underground structure (1).

6. The underwater connection method of a prefabricated box culvert and an existing underground structure according to claim 1 is characterized in that: In the step S2, a steel track (10) is laid at the bottom of the underwater foundation trench, and the prefabricated box culvert (6) is transported to the starting point of the connection between the working well at the end of the underground structure (1) and the prefabricated box culvert (6) on the steel track (10). In the step S3, the prefabricated box culvert (6) is pushed toward the underground structure (1) by means of a jack (7) in cooperation with the steel track (10).

7. The underwater connection method of a prefabricated box culvert and an existing underground structure according to claim 6 is characterized in that: In the step S1, a telescopic limit rod (12) is arranged at the front end of the prefabricated box culvert (6). In the step S3, after the prefabricated box culvert (6) end completely enters the working well of the end of the underground structure (1) and the prefabricated box culvert corbel (9) is tightly fitted with the preliminary ring beam (3) of the underground structure (1), the telescopic limit rod (12) is extended and connected to the flood prevention door (5), and the jack (7) is kept fixed.

8. The underwater connection method of a prefabricated box culvert and an existing underground structure according to claim 1 is characterized in that: In step S5, if the pressure test and leak detection test fails, the leaking point is sealed by grouting, and the pressure test and leak detection test is repeated until there is no leaking point and the pressure test and leak detection test passes.

9. The underwater connection method of a prefabricated box culvert and an existing underground structure according to claim 1 is characterized in that: In step S6, the soil above and on the sides of the pipe gallery is backfilled to level the site.

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