Tunnel inverted arch and central drainage ditch integrated construction method

Abstract

The invention discloses a tunnel inverted arch and central drainage ditch integrated construction method, and relates to the technical field of tunnel construction. The tunnel inverted arch and center drainage ditch integrated construction method comprises the steps that S1, inverted arch steel bars are bound at the inverted arch construction position, prefabricated concrete cushion blocks are placed at the tops of the inverted arch steel bars, and center ditch formwork assemblies are installed at the tops of the prefabricated concrete cushion blocks; s2, inverted arch concrete and center drainage ditch concrete are poured; and after the inverted arch concrete and the center drainage ditch concrete are solidified, an outer mold of the center ditch formwork assembly is removed, and inverted arch filling concrete is poured. According to the construction method, through integrated construction, reserved grooves are avoided, the procedures of mounting and dismounting formworks for multiple times in traditional construction are reduced, and the construction complexity and workload are reduced; and the forming speed of the inverted arch is increased through integrated construction, so that the distance between the inverted arch and the tunnel face can be shortened, overall advancing of tunnel construction is facilitated, and the construction period of tunnel engineering is shortened.

Description

Technical Field

[0001] The present application relates to the technical field of tunnel construction, and in particular to a method for integrating the construction of a tunnel invert and a central drainage ditch. Background Art

[0002] The subsurface structure of tunnel engineering pavement usually has an invert, invert filling and central drainage ditch. As part of the secondary lining of the tunnel, the invert and the central drainage ditch use concrete with a higher strength grade, usually C40; while the invert filling uses concrete with a lower grade, usually C20. Since the concrete grades of the invert filling, the invert and the central drainage ditch are different, they cannot be poured at the same time. In order to ensure construction safety, the tunnel needs to complete the invert construction in a timely manner, and the distance between the invert and the heading should not exceed 50 meters under Grade IV surrounding rock conditions, and should not exceed 40 meters under Grade V surrounding rock conditions. The construction progress of the invert plays a key role in restricting the construction period of the entire tunnel.

[0003] The existing construction method of the central drainage ditch of a tunnel is usually: first cast the inverted arch, then cast the inverted arch filling of the reserved groove with formwork, the width of the groove includes the wall of the central drainage ditch, and then install the formwork and support in the groove, and then cast the wall of the central drainage ditch. In this construction process, the formwork generally uses bamboo plywood, and the support is set up through steel pipes, and the bamboo plywood is fixed with a top support. When supporting the formwork, it is necessary to set up the support through a large number of steel pipes, and adjust the top support to ensure that the formwork is installed in place; when removing the formwork, it is necessary to arrange construction personnel to enter the ditch, remove all the top supports, and then drag the steel pipe support out of the ditch.

[0004] There are many shortcomings in this construction method: 1. The assembly and disassembly process of the template is relatively complicated. Due to the small space of the central ditch and the poor lighting conditions, the assembly and disassembly workload during the construction process is huge, which consumes a lot of time and manpower. 2. Too many template assembly processes are prone to cause a large number of assembly defects, which not only affects the appearance quality, but also makes it difficult to clean the garbage in the drainage ditch, thereby affecting the overall quality of the product. 3. Both the reserved groove and the construction drainage ditch require repeated installation of internal templates and internal supports, which not only increases the complexity of the process, but also causes waste of labor and materials. 4. Since the template needs to be installed and disassembled many times during the construction process, it takes a long time for the final formation of the invert, which is not conducive to the overall advancement of tunnel construction, thereby affecting the construction progress and efficiency of the entire tunnel project. Summary of the invention

[0005] The purpose of this application is to provide an integrated construction method for a tunnel invert and a central drainage ditch to solve the problems of heavy construction workload and long construction time.

[0006] The technical solution adopted by this application to solve its technical problem is:

[0007] A tunnel invert and central drainage ditch integrated construction method, comprising:

[0008] S1. Tie up the inverted arch reinforcement at the inverted arch construction position, place a precast concrete pad on the top of the inverted arch reinforcement, and install a center ditch formwork assembly on the top of the precast concrete pad;

[0009] S2, pouring the inverted arch concrete and the central drainage ditch concrete; after the inverted arch concrete and the central drainage ditch concrete are solidified, the outer formwork of the central ditch formwork assembly is removed, and the inverted arch filling concrete is poured.

[0010] Furthermore, in step S1, the method for installing the center trench template assembly includes:

[0011] Two oppositely arranged half-width integral outer molds are installed on the precast concrete pad, and the two half-width integral outer molds are connected by first tension bolts;

[0012] Two oppositely arranged half-width integral inner molds are installed between the two half-width integral outer molds. The two half-width integral outer molds correspond to the two half-width integral inner molds one by one and are connected by second tension bolts.

[0013] Furthermore, the half-width integral outer mold and the half-width integral inner mold are both steel molds.

[0014] Furthermore, the half-width integral outer mold includes an outer mold upper vertical section, an outer mold horizontal section and an outer mold lower vertical section which are sequentially connected from top to bottom; the outer mold horizontal section is used to support the top of the precast concrete pad, and the outer mold lower vertical section is used to be close to the side of the precast concrete pad.

[0015] Furthermore, the half-width integral inner mold includes a first vertical segment of the inner membrane and a first horizontal segment of the inner membrane which are sequentially connected from top to bottom, and the first vertical segment of the inner membrane is used to be connected to the upper vertical segment of the outer mold through the second tension bolts.

[0016] Furthermore, the half-width integral inner mold also includes a second vertical section of the inner mold and a second horizontal section of the inner mold, the lower end of the second vertical section of the inner mold is connected to one side of the second horizontal section of the inner mold, the other side of the second horizontal section of the inner mold is connected to the upper end of the first vertical section of the inner membrane, and the second horizontal section of the inner mold and the first horizontal section of the inner membrane are respectively located on both sides of the first vertical section of the inner membrane.

[0017] Furthermore, in step S1, the half-width integral outer formwork is also fixedly connected to the inverted arch reinforcement or ground anchor via a first support member.

[0018] Furthermore, the first support member includes a plurality of diagonal steel pipes.

[0019] Furthermore, in step S2, before pouring the inverted arch filling concrete, a second support member is arranged between two inner molds of the center trench formwork assembly.

[0020] Furthermore, the second support member includes a plurality of horizontally arranged inner supporting steel pipes.

[0021] Beneficial effects of this application:

[0022] The integrated construction method of the tunnel invert and central drainage ditch provided in the embodiment of the present application avoids the need for reserved grooves through integrated construction, reduces the process of multiple installation and removal of formwork in traditional construction, and reduces construction complexity and workload; the integrated construction speeds up the formation speed of the invert, thereby shortening the distance between the invert and the heading face, which is beneficial to the overall advancement of tunnel construction, thereby improving construction efficiency and shortening the construction period of the tunnel project. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a schematic diagram of the structure after the inverted arch reinforcement, precast concrete pads and center ditch formwork components are installed;

[0025] Figure 2 This is a schematic diagram of the structure after the invert concrete and the central drainage ditch concrete are poured;

[0026] Figure 3 It is a schematic diagram of the structure after the outer mold of the center groove template assembly is removed;

[0027] Figure 4 It is a schematic diagram of the structure after the invert is filled with concrete;

[0028] Figure 5 It is a schematic diagram of the structure after the inner mold of the center groove template assembly is removed;

[0029] Figure 6 It is a schematic diagram of the structure of the center groove template assembly;

[0030] Figure 7 It is a structural schematic diagram of a half-integral outer mold and a half-integral inner mold.

[0031] Reference numerals:

[0032] 1-Inverted arch reinforcement;

[0033] 2- Precast concrete pads;

[0034] 3-Center groove template assembly;

[0035] 31-half-width integral outer mold;

[0036] 311-vertical section on the outer mold;

[0037] 312-outer mold horizontal section;

[0038] 313-vertical section below the outer mold;

[0039] 32-first tension bolt;

[0040] 33-Half-width integral inner mold;

[0041] 331-first vertical segment of the inner membrane;

[0042] 332-first horizontal segment of the intima;

[0043] 333- the second vertical section of the inner mold;

[0044] 334-second horizontal section of the inner mold;

[0045] 34- second tension bolt;

[0046] 4- first support member;

[0047] 5- second support member;

[0048] 6-Invert concrete;

[0049] 7-Center drain concrete;

[0050] 8-Fill the invert with concrete. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. In the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0052] In the description of this application, the terms "upper", "lower", "left", "right", "front", "back", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on this application. Unless otherwise specified, the above-mentioned directional descriptions can be flexibly set in the process of actual application under the condition that the relative positional relationship shown in the accompanying drawings is satisfied.

[0053] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" 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 direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0054] See also Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 The present application provides a method for integrated construction of a tunnel invert and a central drainage ditch, comprising the following steps:

[0055] S1. Tie up the inverted arch reinforcement 1 at the inverted arch construction position, place a precast concrete pad 2 on the top of the inverted arch reinforcement 1, and install a center ditch formwork assembly 3 on the top of the precast concrete pad 2.

[0056] Before construction, the specific positions and sizes of the invert, invert filling and central drainage ditch are determined according to the tunnel design drawings, and the precast concrete pad 2 is prepared in advance to ensure that its strength and size meet the design requirements. The concrete grade of the precast concrete pad 2 is the same as that of the invert and central drainage ditch.

[0057] During construction, the inverted arch reinforcement 1 is tied at the inverted arch construction position to ensure that the spacing and position of the inverted arch reinforcement 1 meet the design requirements. After the inverted arch reinforcement 1 is tied, a plurality of precast concrete pads 2 are placed on the top of the inverted arch reinforcement 1 along the longitudinal direction of the tunnel. The precast concrete pads 2 are used to support the center trench formwork assembly 3 to ensure the installation height and stability of the center trench formwork assembly 3. Then, the center trench formwork assembly 3 is installed on the top of the precast concrete pads 2. Figure 1 The center groove template assembly 3 is mainly composed of a pair of outer molds and a pair of inner molds arranged between the pair of outer molds.

[0058] S2, pouring inverted arch concrete and central drainage ditch concrete; after the inverted arch concrete and central drainage ditch concrete are solidified, the outer form of the central ditch formwork assembly 3 is removed, and the inverted arch filling concrete is poured.

[0059] See also Figure 2 , pour the inverted arch concrete 6 in the inverted arch steel bar 1, and pour the center drainage ditch concrete 7 in the center ditch formwork assembly 3. The inverted arch concrete 6 and the center drainage ditch concrete 7 are C40 concrete with the same grade. During the pouring process, a vibrating rod is used to vibrate the concrete to avoid quality problems such as honeycomb and rough surface, thereby ensuring the pouring quality of the concrete.

[0060] See also Figure 3 After the inverted arch concrete and the central drainage ditch concrete are solidified, the outer mold of the central ditch formwork assembly 3 is removed, and the inner mold of the central ditch formwork assembly 3 is reinforced. Removing the outer mold of the central ditch formwork assembly 3 can expose the outer side of the ditch wall of the central drainage ditch, so that the inverted arch filling concrete 8 is tightly connected to the ditch wall of the central drainage ditch when the inverted arch filling concrete 8 is subsequently poured. Reinforcing the inner mold of the central ditch formwork assembly 3 can improve the firmness of the inner mold fixation, and prevent the inner mold from deformation or displacement when the inverted arch filling concrete 8 is subsequently poured.

[0061] See also Figure 4 , pour the inverted arch filling concrete 8 above the inverted arch, the inverted arch filling concrete 8 is grade C20 concrete, and during the pouring process, the concrete is vibrated by a vibrating rod to avoid quality problems such as honeycomb and rough surface, thereby ensuring the pouring quality of the concrete, and at the same time, the inner mold of the center ditch template assembly 3 is used to support and protect the ditch wall of the center drainage ditch to avoid the damage to the ditch wall caused by the force generated on the ditch wall of the center drainage ditch during the vibration of the inverted arch filling concrete 8.

[0062] See also Figure 5 After the inverted arch filling concrete 8 solidifies, the inner mold of the central ditch template assembly 3 is removed. Then the prefabricated ditch cover is installed on the top of the central drainage ditch to complete the whole process.

[0063] The integrated construction method of the tunnel invert and central drainage ditch provided in the embodiment of the present application avoids the reserved groove through integrated construction, reduces the process of installing and removing the templates many times in traditional construction, and reduces the construction complexity and workload. The integrated construction speeds up the formation speed of the invert, thereby shortening the distance between the invert and the face, which is beneficial to the overall advancement of tunnel construction, thereby improving construction efficiency and shortening the construction period of the tunnel project. During the entire construction process, traffic in the tunnel can be achieved through the invert trestle without affecting the construction of other processes in the tunnel.

[0064] In some embodiments, see Figure 6In step S1, the method for installing the center trench template assembly 3 comprises the following steps:

[0065] Two oppositely arranged half-width integral outer molds 31 are installed on the precast concrete pad 2, and the two half-width integral outer molds 31 are connected by first tension bolts 32; two oppositely arranged half-width integral inner molds 33 are installed between the two half-width integral outer molds 31, and the two half-width integral outer molds 31 correspond to the two half-width integral inner molds 33 one by one and are connected by second tension bolts 34. When the central ditch formwork assembly 3 is installed, a space for pouring the central drainage ditch concrete to form the ditch wall of the central drainage ditch is formed between the top of the precast concrete pad 2, the two half-width integral outer molds 31 and the two half-width integral inner molds 33.

[0066] The use of a half-width integral outer mold 31 and a half-width integral inner mold 33 not only reduces the workload of on-site assembly, but also makes the installation and disassembly of the mold more convenient, which can significantly shorten the construction time, and can ensure the flatness and splicing accuracy of the mold surface, reduce the splicing gap, and thus improve the flatness and appearance quality of the concrete surface. The outer mold and the inner mold are connected by the first tension bolt 32 and the second tension bolt 34 to form an integral structure, which enhances the stability of the mold, can effectively resist the lateral pressure during concrete pouring, and avoid deformation of the mold. The use of tension bolts can also accurately control the spacing and position of the inner mold and the outer mold to ensure the dimensional accuracy of the central drainage ditch.

[0067] In some embodiments, the half-width integral outer mold 31 and the half-width integral inner mold 33 are both steel molds. For example, the steel mold can be composed of a steel plate and an I-beam back rib fixed on the surface of the steel plate. Accordingly, the steel mold is made of high-strength steel, has good compression and bending resistance, can withstand large construction loads, and has a long service life, can be used repeatedly, and is not easy to be damaged, thereby reducing the investment and maintenance costs of the mold.

[0068] In some embodiments, see Figure 6 , Figure 7 The half-width integral outer mold 31 includes an outer mold upper vertical section 311, an outer mold horizontal section 312, and an outer mold lower vertical section 313 connected in sequence from top to bottom; the outer mold horizontal section 312 is used to support the top of the precast concrete pad 2, and the outer mold lower vertical section 313 is used to cling to the side of the precast concrete pad 2. The outer mold upper vertical section 311 and the outer mold lower vertical section 313 are respectively located on both sides of the outer mold horizontal section 312, and the outer mold upper vertical sections 311 of the two half-width integral outer molds 31 are connected by a plurality of first tension bolts 32.

[0069] Accordingly, the segmented structure of the upper vertical section 311 of the outer mold, the horizontal section 312 of the outer mold, and the lower vertical section 313 of the outer mold enables the outer mold to provide good support and stability in different directions. The horizontal section 312 of the outer mold is directly supported on the top of the precast concrete pad 2, and can position the height of the outer mold; the lower vertical section 313 of the outer mold is close to the side of the precast concrete pad 2, and can position the horizontal position of the outer mold, thereby enabling the outer mold to be quickly positioned and fixed during installation, reducing the installation workload.

[0070] In some embodiments, see Figure 6 , Figure 7 The half-width integral inner mold 33 includes a first vertical segment 331 and a first horizontal segment 332 of the inner mold connected sequentially from top to bottom, and the first vertical segment 331 of the inner mold is used to be connected to the upper vertical segment 311 of the outer mold through the second tension bolt 34. When the half-width integral inner mold 33 is installed, one end of the first horizontal segments 332 of the inner molds of the two half-width integral inner molds 33 are in contact.

[0071] The first vertical section 331 of the inner mold is connected to the upper vertical section 311 of the outer mold by the second tension bolt 34, forming a rigid connection, which can effectively resist the lateral pressure during concrete pouring and reduce the deformation of the mold. This structure makes the inner mold and the outer mold form a whole, enhancing the overall stability of the mold system.

[0072] Exemplarily, the half-width integral inner mold 33 also includes a second vertical section 333 of the inner mold and a second horizontal section 334 of the inner mold, the lower end of the second vertical section 333 of the inner mold is connected to one side of the second horizontal section 334 of the inner mold, the other side of the second horizontal section 334 of the inner mold is connected to the upper end of the first vertical section 331 of the inner membrane, and the second horizontal section 334 of the inner mold and the first horizontal section 332 of the inner membrane are respectively located on both sides of the first vertical section 331 of the inner membrane.

[0073] Correspondingly, the second vertical section 333 of the inner mold contacts the upper vertical section 311 of the outer mold, which can accurately control the position and size of the inner mold and ensure the construction accuracy of the central drainage ditch. At the same time, by utilizing the cooperation of the second vertical section 333 of the inner mold and the second horizontal section 334 of the inner mold, when the invert is filled with concrete, a groove for accommodating the ditch cover can be directly formed on the top of the central drainage ditch to facilitate the subsequent installation of the ditch cover.

[0074] In order to improve the firmness of the center groove template assembly 3 during installation, see Figure 1 In step S1, the half-width integral outer formwork 31 is also fixedly connected to the inverted arch reinforcement 1 or the ground anchor through the first support member 4. The first support member 4 may include a plurality of diagonal bracing steel pipes.

[0075] Accordingly, the half-width integral outer formwork 31 is fixedly connected to the inverted arch reinforcement 1 or the ground anchor through the first support member 4, which can significantly enhance the stability of the outer formwork during construction, effectively resist the lateral pressure generated when pouring the central drainage ditch concrete, reduce the deformation and displacement of the formwork, effectively avoid safety accidents caused by unstable formwork, and improve construction safety. After the construction is completed, the first support member 4 can be reserved in the concrete.

[0076] In step S2, before pouring the inverted arch filling concrete, a second support member 5 is arranged between the two inner molds of the center trench formwork assembly 3. The second support member 5 may include a plurality of horizontally arranged inner support steel pipes. Specifically, the inner support steel pipes are supported between the first vertical sections 331 of the inner membranes of the two half-width integral inner molds 33.

[0077] Correspondingly, a second support member 5 is provided between the two inner molds of the center trench formwork assembly 3, which can effectively support the two inner molds and prevent the inner molds from being deformed or displaced due to lateral pressure when pouring the inverted arch and filling concrete, thereby improving construction safety.

[0078] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed in the present application should be covered within the protection scope of the present application.

Claims

1. A method for integrated construction of a tunnel invert and a central drainage ditch, characterized in that: include: S1, tying the inverted arch reinforcement (1) at the inverted arch construction position, placing a precast concrete pad (2) on the top of the inverted arch reinforcement (1), and installing a center trench template assembly (3) on the top of the precast concrete pad (2); S2, pouring the inverted arch concrete and the central drainage ditch concrete; after the inverted arch concrete and the central drainage ditch concrete are solidified, the outer formwork of the central ditch formwork assembly (3) is removed, and the inverted arch filling concrete is poured.

2. The method for integrated construction of tunnel invert and central drainage ditch according to claim 1, characterized in that: In step S1, the method for installing the center groove template assembly (3) includes: Two half-width integral outer molds (31) arranged opposite to each other are installed on the precast concrete pad (2), and the two half-width integral outer molds (31) are connected via first tension bolts (32); Two oppositely arranged half-width integral inner molds (33) are installed between the two half-width integral outer molds (31); the two half-width integral outer molds (31) correspond to the two half-width integral inner molds (33) in a one-to-one manner and are connected via second tension bolts (34).

3. The integrated construction method of tunnel invert and central drainage ditch according to claim 2, characterized in that: The half-width integral outer mold (31) and the half-width integral inner mold (33) are both steel mold plates.

4. The integrated construction method of tunnel invert and central drainage ditch according to claim 2, characterized in that: The half-width integral outer mold (31) comprises an outer mold upper vertical section (311), an outer mold horizontal section (312), and an outer mold lower vertical section (313) which are sequentially connected from top to bottom; the outer mold horizontal section (312) is used to support the top of the precast concrete pad (2), and the outer mold lower vertical section (313) is used to closely contact the side of the precast concrete pad (2).

5. The integrated construction method of tunnel invert and central drainage ditch according to claim 4, characterized in that: The half-width integral inner mold (33) comprises a first vertical section (331) of the inner membrane and a first horizontal section (332) of the inner membrane which are sequentially connected from top to bottom, and the first vertical section (331) of the inner membrane is used to be connected to the upper vertical section (311) of the outer mold via the second tension bolts (34).

6. The method for integrated construction of tunnel invert and central drainage ditch according to claim 5, characterized in that: The half-width integral inner mold (33) also includes a second vertical section (333) of the inner mold and a second horizontal section (334) of the inner mold. The lower end of the second vertical section (333) of the inner mold is connected to one side of the second horizontal section (334) of the inner mold, and the other side of the second horizontal section (334) of the inner mold is connected to the upper end of the first vertical section (331) of the inner membrane. The second horizontal section (334) of the inner mold and the first horizontal section (332) of the inner membrane are respectively located on both sides of the first vertical section (331) of the inner membrane.

7. The integrated construction method of tunnel invert and central drainage ditch according to claim 2, characterized in that: In step S1, the half-width integral outer formwork (31) is also fixedly connected to the inverted arch reinforcement (1) or the ground anchor via the first support member (4).

8. The integrated construction method of tunnel invert and central drainage ditch according to claim 7, characterized in that: The first support member (4) comprises a plurality of diagonal steel pipes.

9. The integrated construction method of tunnel invert and central drainage ditch according to claim 1, characterized in that: In step S2, before pouring the inverted arch filling concrete, a second support member (5) is arranged between two inner molds of the central trench formwork assembly (3).

10. The integrated construction method of tunnel invert and central drainage ditch according to claim 9, characterized in that: The second support member (5) comprises a plurality of horizontally arranged inner support steel pipes.

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