Detachable system for retaining structure reserved tunnel portal and construction method of detachable system

Abstract

The invention discloses a detachable system for a retaining structure reserved tunnel portal and a construction method of the detachable system. The detachable system at least comprises but not limited to a supporting body, a first reinforcement cage and a second reinforcement cage. Connecting plates are arranged on the contact surfaces of the first reinforcement cage and the second reinforcement cage with the support body; the supporting body is detachably connected with the connecting plate; according to the scheme, the detachable supporting body is arranged at the reserved tunnel portal, rapid disassembly and assembly of the supporting body can be achieved, meanwhile, the disassembled supporting body can be recycled, a thick underground diaphragm wall does not need to be broken, the overall structure cannot be affected, the strength of the underground diaphragm wall structure is guaranteed, and the construction cost is reduced. And meanwhile, the grooving efficiency and grooving precision of the reserved tunnel portal can be improved.

Description

Technical Field

[0001] The invention relates to the field of building construction, and in particular to a detachable system for a reserved door of an enclosure structure and a construction method thereof. Background Art

[0002] With the development of urban construction, there are more and more ultra-deep and ultra-thick underground continuous wall projects, and the demolition of the underground continuous wall at the entrance and exit and other ancillary connecting areas is a key factor affecting the safety, quality and progress of the project. At the same time, due to the excessive weight of the concrete blocks after the demolition of the ultra-deep and ultra-thick underground continuous wall, the transfer and hoisting methods of the concrete blocks in the narrow station are very demanding, which is also the most important key factor affecting construction safety.

[0003] At present, the commonly used methods for breaking the ground-connected wall mainly include: diamond wire saw cutting and blasting machine combined with manual labor. Diamond wire saw cutting is a method of cutting concrete using a high-speed rotating diamond rope. Blasting machine breaking mainly uses strong impact and crushing force to break the hard continuous wall concrete into small pieces.

[0004] The two processes have obvious shortcomings during construction, with prominent quality and safety risks, and more waste generated, which is not conducive to environmental protection. Taking rope saw cutting as an example, the existing technology is mostly achieved by setting up an operating platform with a rope saw cutting machine and an electric hoist, which has extremely high safety risks, damages existing structures, is prone to cross-operation, has high costs, high operating technical requirements, and a long construction period. It is difficult to hoist and is not conducive to environmental protection. Summary of the invention

[0005] The purpose of the present invention is to provide a detachable system for reserved openings in enclosure structures and a construction method thereof in view of the above-mentioned deficiencies, so as to solve the problems in the prior art of demolishing ground-connected walls, such as high safety risks, damage to existing structures, easy cross-operation, high cost, high operating technical requirements, long construction period, difficulty in lifting, and disadvantageous to environmental protection.

[0006] The present invention is achieved through the following scheme:

[0007] A detachable system for reserved openings in enclosure structures includes at least but is not limited to a support body, a first steel cage and a second steel cage; connecting plates are provided on the contact surfaces of the first steel cage and the second steel cage with the support body; the support body and the connecting plates are detachably connected.

[0008] Based on the above-mentioned structure of a detachable system for reserved openings in enclosure structures, the first steel cage is arranged on the upper end surface of the support body, the second steel cage is arranged on the lower end surface of the support body, the connecting plate is provided with connecting holes, and the supporting body is provided with locking holes matching the connecting holes, and the supporting body and the connecting plate are connected as a whole by bolts.

[0009] Based on the above-mentioned structure of a detachable system for reserved door openings in enclosure structures, the support body includes a side wall support portion and a central support portion; the central support portion is arranged between the two side wall support portions, and a detachable filling layer is arranged between the side support portion and the central support portion.

[0010] Based on the above-mentioned structure of a detachable system for reserved openings in enclosure structures, the side wall support portion includes a first support vertical plate, a first support side plate and a first support end plate; the first support side plates are arranged in parallel in two numbers, and the first support vertical plate is arranged at the center position of the two first support side plates to form an I-shaped structure; the first support end plates are arranged on both sides of the I-shaped structure, and the first support end plates are respectively arranged perpendicular to the first support vertical plate and the first support side plate; the locking holes are evenly arranged on the first support side plates.

[0011] Based on the above-mentioned structure of a detachable system for reserved door openings in enclosure structures, the central support portion includes a first support column, a second support column and a central filling layer, and the central filling layer is arranged between the first support column and the second support column; the first support column and the second support column have the same structure.

[0012] Based on the above-mentioned structure of a detachable system for reserved openings in enclosure structures, the first support column includes two support legs arranged in parallel, a cavity structure for pouring concrete is arranged between adjacent support legs, and the support legs include a second support vertical plate, a second support side plate and a second support end plate; the second support side plates are arranged in parallel in two numbers, and the second support vertical plate is arranged at the center position of the two second support side plates to form an I-shaped structure; the second support end plates are arranged on both sides of the I-shaped structure, and the second support end plates are respectively arranged perpendicular to the second support vertical plate and the second support side plate; locking holes are evenly arranged on the second support side plates.

[0013] Based on the structure of the above-mentioned detachable system for reserved door openings in enclosure structures, the end face of the first support column away from the side wall support portion is the inner side, the end face of the first support column close to the side wall support portion is the outer side, and positioning steel bars and limiting steel bars are arranged between the inner support legs of the first support column and the second support column.

[0014] Based on the above-mentioned structure of a detachable system for reserved openings in enclosure structures, the limiting steel bars are arranged between the second supporting vertical plates of the inner supporting legs of the first supporting column and the second supporting column, and the limiting steel bars are arranged between the second supporting end plates of the inner supporting legs of the first supporting column and the second supporting column; the positioning steel bars are used to position the central filling layer so that there is a concave cavity in the central supporting part, and the limiting steel bars are used to limit the end position of the central filling layer.

[0015] Based on the above-mentioned structure of a detachable system for reserved door openings in enclosure structures, the central filling layer includes a foam board and a wooden box, the foam board is arranged in the wing panels opposite to each other on the second support end panels of the inner support legs of the first support column and the second support column, the height of the foam board is the same as the height of the wing panel of the second support end panel, and the wooden box is arranged in the cavity between the foam boards on both sides.

[0016] The scheme also provides a construction method for a reserved hole door of a retaining structure, comprising the following steps:

[0017] Step 1: Cast underground wall. According to the construction plan and combined with the construction technology level and mechanical combination, the guide wall is laid out and positioned. A special trenching machine is used to dig a narrow and deep trench in 6m sections along the design outline under the condition of mud wall protection. After cleaning the trench, a steel cage is sunk in the trench and underwater concrete is poured to build a section of reinforced concrete wall. Several wall sections are connected into a whole to form a continuous underground wall.

[0018] Step 2: When the main ground-connected wall is constructed to the entrance or wind pavilion, the dividing line must be accurately laid out and the grooves must be accurately marked. The groove sections at this location must be grooved one by one and the steel cage processing must be started at the same time;

[0019] Step 3: Set the detachable system in the marked portal area, insert the concrete conduit into the avoidance groove, cast the second steel cage and support legs, and then cast the retaining wall and support columns in the concrete receiving cavity;

[0020] Step three also includes the processing of the steel cage, which is carried out on a steel cage platform with a distance scale. The upper and lower elevation lines corresponding to the opening position are accurately marked on the platform. The processing of a steel cage should be divided into three sections, and finally assembled and connected by bolts to form the final shape.

[0021] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0022] 1. This scheme can realize the rapid disassembly and assembly of the support body by setting a detachable support body at the reserved hole door. At the same time, the disassembled support body can also be recycled. This scheme does not need to break the thick ground-connected wall, will not affect the overall structure, ensure the strength of the ground-connected wall structure, and at the same time can also improve the grooving efficiency and grooving accuracy of the reserved hole door.

[0023] 2. This scheme is mainly used for the construction of retaining structures in the area where the auxiliary structures of the main foundation pit are connected. This method is simple to construct and the device is easy to manufacture. The processes involved are all existing. The device has a high recycling rate after the main structure construction is completed. With this device, the period of breaking the tunnel gate is shortened, safe and controllable, and energy-saving and environmentally friendly. The economic benefits are extremely obvious. With this device, the disturbance to the existing structure is minimal when the tunnel gate is broken in the later stage, which reduces the adverse effects on the main structure and provides a guarantee for the safety of the underground structure.

[0024] 3. This solution not only solves the problems of vibration caused by chiseling and cutting on the existing structure, water leakage in the structure, and difficulty in lifting in a small space, but also improves the reusability of retaining structure materials in deep foundation pit construction and saves the cost of waste soil disposal. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall vertical cross-sectional structure of the present invention;

[0026] Figure 2 It is a structural schematic diagram of the connecting plate in the present invention;

[0027] Figure 3 It is a schematic diagram of the overall transverse cross-sectional structure of the present invention;

[0028] Figure 4 It is an enlarged structural schematic diagram of the central support part in the present invention;

[0029] Figure 5 It is a schematic diagram of the overall structure of the side wall support part in the present invention;

[0030] Figure 6 It is a schematic diagram of an application scenario of the disassembly system of the present invention;

[0031] Markings in the figure: 1. support body; 2. first steel cage; 3. second steel cage; 4. connecting plate; 5. concrete conduit; 11. locking hole; 12. side wall support part; 13. central support part; 121. first support vertical plate; 122. first support side plate; 123. first support end plate; 131. first support column; 132. second support column; 133. central filling layer; 134. supporting leg; 135. cavity structure; 136. second support vertical plate; 137. second support side plate; 138. second support end plate; 139. positioning steel bar; 1310. limiting steel bar; 1331. foam board; 1332. wooden box; 41. connecting hole; 42. plate structure; 43. avoidance groove. DETAILED DESCRIPTION

[0032] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0033] Any feature disclosed in this specification (including any additional claims and abstract), unless otherwise stated, may be replaced by other equivalent or alternative features having similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0034] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "left", "right", etc. are based on the directions 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 predetermined direction, be constructed and operated in a predetermined direction, and therefore cannot be understood as a limitation on the present invention.

[0035] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0036] Example 1

[0037] like Figure 1 to Figure 5 As shown, the present invention provides a technical solution:

[0038] A detachable system for reserved openings in enclosure structures, which at least includes but is not limited to a support body 1, a first steel cage 2 and a second steel cage 3; a connecting plate 4 may be provided on the contact surface between the first steel cage 2 and the second steel cage 3 and the support body 1; the support body 1 and the connecting plate 4 are detachably connected.

[0039] Based on the above structure, by arranging a detachable support body 1 at the reserved opening, the support body 1 can be quickly disassembled and assembled, and the disassembled support body 1 can also be recycled. This solution does not require the removal of thicker ground-connected walls and will not affect the overall structure, thereby ensuring the strength of the ground-connected wall structure. At the same time, it can also improve the grooving efficiency and grooving accuracy of the reserved opening.

[0040] As an example, the first steel cage 2 is arranged on the upper end surface of the support body 1, the second steel cage 3 is arranged on the lower end surface of the support body 1, a connecting hole 41 is arranged on the connecting plate 4, and a locking hole 11 matching the connecting hole 41 is arranged on the support body 1, and the support body 1 and the connecting plate 4 are connected as a whole by bolts.

[0041] Based on the above structure, the support body 1 can be easily dismantled and installed later through bolt connection.

[0042] As an example, the support body 1 may include a side wall support portion 12 and a central support portion 13 ; the central support portion 13 is disposed between the two side wall support portions 12 , and a detachable filling layer is disposed between the side support portions and the central support portion 13 .

[0043] Based on the above structure, this solution connects the side wall support part 12 with other ground-connected wall structures in the reserved portal area as a whole during pouring, and provides the main supporting force for the reserved portal area by setting the central support part 13, which cooperates with the side wall support part 12 to form an overall support for the reserved portal area. The filling layer only serves as a filling layer to prevent concrete from entering it during pouring. On the one hand, it can reduce the amount of concrete used, and on the other hand, it can also facilitate subsequent demolition.

[0044] As an example, the side wall support portion 12 may include a first support vertical plate 121, a first support side plate 122 and a first support end plate 123; two first support side plates 122 are arranged in parallel, and the first support vertical plate 121 is arranged at the center of the two first support side plates 122 to form an I-shaped structure; the first support end plates 123 are arranged on both sides of the I-shaped structure, and the first support end plates 123 are respectively arranged perpendicular to the first support vertical plate 121 and the first support side plate 122; the locking holes 11 are evenly arranged on the first support side plates 122;

[0045] Based on the above structure, by setting the side wall support part 12 as an I-shaped structure, the support of the side wall of the reserved tunnel door area can be guaranteed, and by setting a locking hole 11 on the first supporting side plate 122, it can be quickly connected to the connecting hole 41 on the connecting plate 4 as a whole; the first supporting end plate 123 is used to increase the contact area with the underground soil.

[0046] As an example, the central support portion 13 may include a first support column 131, a second support column 132 and a central filling layer 133, wherein the central filling layer 133 is disposed between the first support column 131 and the second support column 132; the first support column 131 and the second support column 132 have the same structure;

[0047] The first support column 131 may include two support legs 134 arranged in parallel, a cavity structure 135 for pouring concrete is arranged between adjacent support legs 134, and the support leg 134 includes a second support vertical plate 136, a second support side plate 137 and a second support end plate 138; two second support side plates 137 are arranged in parallel, and the second support vertical plate 136 is arranged at the center of the two second support side plates 137 to form an I-shaped structure; the second support end plates 138 are arranged on both sides of the I-shaped structure, and the second support end plates 138 are respectively arranged perpendicular to the second support vertical plate 136 and the second support side plate 137; the locking holes 11 are evenly arranged on the second support side plates 137;

[0048] The end surface of the first support column 131 away from the side wall support portion 12 is the inner side, and the end surface of the first support column 131 close to the side wall support portion 12 is the outer side. A positioning steel bar 139 and a limiting steel bar 1310 are arranged between the support legs 134 on the inner sides of the first support column 131 and the second support column 132;

[0049] The limiting steel bar 1310 is arranged between the second supporting vertical plate 136 of the inner supporting leg 134 of the first supporting column 131 and the second supporting column 132, and the limiting steel bar 1310 is arranged between the second supporting end plate 138 of the inner supporting leg 134 of the first supporting column 131 and the second supporting column 132; the positioning steel bar 139 is used to position the central filling layer 133 so that there is a concave cavity in the central supporting part 13, and the limiting steel bar 1310 is used to limit the end position of the central filling layer 133.

[0050] Based on the above structure, the initial position of the central filling layer 133 is limited by the positioning steel bar 139, and the end position of the central filling layer 133 is limited by the limiting steel bar 1310. After the central filling layer 133 is added, the central support portion 13 has a concave concrete accommodating cavity, that is, the cavity formed between the positioning steel bar 139 and the second support end. By pouring concrete in the cavity, a retaining wall that is much thinner than a conventional ground-connected wall can be formed. After completion, the central filling layer 133 can be removed and a simple mechanical structure can be used to break the thinner retaining wall, thereby reducing the construction difficulty and improving the installation accuracy of the reserved door.

[0051] As an example, the central filling layer 133 may include a foam board 1331 and a wooden box 1332. The foam board 1331 is arranged in the opposite wing panels on the second support end panel 138 of the inner support legs 134 of the first support column 131 and the second support column 132. The height of the foam board 1331 is the same as the height of the wing panel of the second support end panel 138. The wooden box 1332 is arranged in the cavity between the foam boards 1331 on both sides.

[0052] Based on the above structure, in this solution, since the inner area near the second support plate needs to be removed by screws later, foam is used for support, and the center position is supported by a wooden box 1332 and a limiting steel bar 1310. The foam board 1331 and the wooden box 1332 form a support surface with the same height as the entire support leg 134, which is used to interfere with the concrete accommodating cavity so that the concrete forms a retaining wall at the specified position.

[0053] As an example, limiting steel bars 1310, positioning steel bars 139 and a filling layer are also provided between the side wall support portion 12 and the central support portion 13, and their configuration is the same as that of the central support portion 13, which will not be described in detail here.

[0054] As an example, the connecting plate 4 may include a plate structure 42 and an avoidance groove 43 , the connecting hole 41 and the avoidance groove 43 are arranged on the plate structure 42 , and the setting position of the avoidance groove 43 matches the position of the supporting leg 134 .

[0055] Based on the above structure, the avoidance groove 43 is provided so that the concrete conduit 5 can be inserted to pour the support leg 134 and the second reinforcement cage 3 under the support leg 134 .

[0056] This solution not only solves the problems of vibration caused by chiseling and cutting on the existing structure, structural leakage, and difficulty in lifting in a small space, but also improves the reusability of retaining structure materials in deep foundation pit construction and saves the cost of waste soil disposal.

[0057] Example 2

[0058] like Figure 1 As shown, the present invention provides a technical solution:

[0059] A construction method for a reserved hole door of an enclosure structure comprises the following steps:

[0060] Step 1: Cast underground wall. According to the construction plan and combined with the construction technology level and mechanical combination, the guide wall is laid out and positioned. A special trenching machine is used to dig a narrow and deep trench in 6m sections along the design outline under the condition of mud wall protection. After cleaning the trench, a steel cage is sunk in the trench and underwater concrete is poured to build a section of reinforced concrete wall. Several wall sections are connected into a whole to form a continuous underground wall.

[0061] Step 2: When the main ground-connected wall is constructed to the entrance or wind pavilion, the dividing lines must be accurately laid out and the grooves should be accurately marked. The groove sections at this location should be grooved one by one and the steel cage processing should be started at the same time.

[0062] Step 3: Set the detachable system in the marked portal area, insert the concrete conduit 5 into the avoidance groove 43, cast the second steel cage 3 and the support leg 134, and then cast in the concrete accommodating cavity to form a retaining wall and support columns.

[0063] Step three may also include the processing of the steel cage, which is carried out on a steel cage platform with a distance scale. The upper and lower elevation lines corresponding to the opening position are accurately marked on the platform. A steel cage should be processed in three sections and finally assembled and connected by bolts to form the final shape.

[0064] In this solution, the foam board 1331, the wooden box 1332, the side wall support part 12 and the central support part 13 are all detachable structures, which are convenient for subsequent recycling. After the foam board 1331 and the wooden box 1332 and other supporting structures are dismantled, only a thin retaining wall is reserved, which is convenient for the final demolition of the retaining wall.

[0065] The processing of the dismantling system of this scheme is relatively complicated, and the decomposition steps are as follows: first, the supporting vertical plate and supporting side plate are processed in the factory, and each supporting side plate has 8 bolt holes in total, and the connecting plate has 4 bolt holes in total of 48; each supporting leg 134 needs to be split into two sections for processing, and the middle bolt hole is processed into a long strip hole to reserve a loose bolt movable position, so that after the bolt is loosened later, the upper column moves down and easily moves out of the column; after all the supporting legs 134 are assembled, they are placed vertically on the processing platform, and at this time, the positioning steel bars 139 are welded on the web of the column and a cavity is reserved (for concrete filling on the soil side), and then the foam board 1331 is placed within the width of all the wing plates. After the foam board 1331 is fixed, the processed wooden box 1332 is placed between the foam boards 1331, and then the wooden box 1332 is fixed with the limiting steel bar 1310. The connection between the main reinforcement of the steel cage and the capping steel plate adopts lap welding, and the main reinforcement is bent to 90° in advance and welded to the top and bottom steel plates. Finally, the first steel cage 2 and the second steel cage 3 are respectively connected to the demolition system by bolts.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A detachable system for reserved openings of enclosure structures, characterized in that: At least includes but is not limited to a support body, a first steel cage and a second steel cage; a connecting plate is arranged on the contact surface between the first steel cage and the second steel cage and the support body; the support body and the connecting plate are detachably connected.

2. A detachable system for reserved openings of enclosure structures according to claim 1, characterized in that: The first steel cage is arranged on the upper end surface of the support body, the second steel cage is arranged on the lower end surface of the support body, the connecting plate is provided with a connecting hole, the supporting body is provided with a locking hole matching the connecting hole, and the supporting body and the connecting plate are connected as a whole by bolts.

3. A detachable system for reserved openings of enclosure structures as claimed in claim 2, characterized in that: The support body comprises a side wall support portion and a central support portion; the central support portion is arranged between the two side wall support portions, and a detachable filling layer is arranged between the side support portion and the central support portion.

4. A detachable system for reserved openings of enclosure structures as claimed in claim 3, characterized in that: The side wall support portion includes a first support vertical plate, a first support side plate and a first support end plate; the first support side plates are arranged in parallel in two numbers, and the first support vertical plate is arranged at the center position of the two first support side plates to form an I-shaped structure; the first support end plates are arranged on both sides of the I-shaped structure, and the first support end plates are respectively arranged perpendicular to the first support vertical plate and the first support side plate; the locking holes are evenly arranged on the first support side plates.

5. A detachable system for reserved openings of enclosure structures as claimed in claim 4, characterized in that: The central support portion comprises a first support column, a second support column and a central filling layer, wherein the central filling layer is arranged between the first support column and the second support column; the first support column and the second support column have the same structure.

6. A detachable system for reserved openings of enclosure structures as claimed in claim 5, characterized in that: The first support column includes two support legs arranged in parallel, a cavity structure for pouring concrete is arranged between adjacent support legs, and the support legs include a second support vertical plate, a second support side plate and a second support end plate; the second support side plates are arranged in parallel in two, and the second support vertical plate is arranged at the center position of the two second support side plates to form an I-shaped structure; the second support end plates are arranged on both sides of the I-shaped structure, and the second support end plates are respectively arranged perpendicular to the second support vertical plate and the second support side plate; locking holes are evenly arranged on the second support side plates.

7. A detachable system for reserved openings of enclosure structures as claimed in claim 6, characterized in that: The end face of the first support column away from the side wall support portion is the inner side, and the end face of the first support column close to the side wall support portion is the outer side. Positioning steel bars and limiting steel bars are arranged between the inner support legs of the first support column and the second support column.

8. A detachable system for reserved openings of enclosure structures as claimed in claim 7, characterized in that: The limiting steel bars are arranged between the second supporting vertical plates of the inner supporting legs of the first supporting column and the second supporting column, and the limiting steel bars are arranged between the second supporting end plates of the inner supporting legs of the first supporting column and the second supporting column; the positioning steel bars are used to position the central filling layer so that there is a concave cavity in the central supporting part, and the limiting steel bars are used to limit the end position of the central filling layer.

9. A detachable system for reserved openings of enclosure structures as claimed in claim 8, characterized in that: The central filling layer includes a foam board and a wooden box. The foam board is arranged in the wing plates opposite to each other on the second support end plates of the inner support legs of the first support column and the second support column. The height of the foam board is the same as the height of the wing plate of the second support end plate. The wooden box is arranged in the cavity between the foam boards on both sides.

10. A construction method for reserved openings in enclosure structures, characterized in that: The following steps are involved: Step 1: Cast underground wall. According to the construction plan and combined with the construction technology level and mechanical combination, the guide wall is laid out and positioned. A special trenching machine is used to dig a narrow and deep trench in 6m sections along the design outline under the condition of mud wall protection. After cleaning the trench, a steel cage is sunk in the trench and underwater concrete is poured to build a section of reinforced concrete wall. Several wall sections are connected into a whole to form a continuous underground wall. Step 2: When the main ground-connected wall is constructed to the entrance or wind pavilion, the dividing line must be accurately laid out and the grooves must be accurately marked. The groove sections at this location must be grooved one by one and the steel cage processing must be started at the same time; Step 3: Set the detachable system in the marked portal area, insert the concrete conduit into the avoidance groove, cast the second steel cage and support legs, and then cast the retaining wall and support columns in the concrete receiving cavity; Step three also includes the processing of the steel cage, which is carried out on a steel cage platform with a distance scale. The upper and lower elevation lines corresponding to the opening position are accurately marked on the platform. The processing of a steel cage should be divided into three sections, and finally assembled and connected by bolts to form the final shape.

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