A tunnel inner buffer material horizontal jet grouting laying method and laying structure

Abstract

The application provides a tunnel inner buffering material horizontal injection pouring laying method and laying structure, foam concrete is laid between primary support and secondary lining in a tunnel; a plurality of steel formworks are installed on the inner side of the primary support, adjacent steel formworks are fixed through bolt connection to form a formwork whole, a space is formed between the formwork whole and the primary support, and the space is used for laying foam concrete; the shape of the formwork whole is matched with the primary support; a steel formwork end is installed, a steel formwork end on the steel formwork at the top of the tunnel is provided with a preset pouring opening, the pouring opening is communicated with the space; foam concrete is horizontally injected into the space from the pouring opening of the top steel formwork, and the foam concrete is poured and formed from bottom to top; after the foam concrete reaches a set strength, the steel formwork is removed. The application solves the problem of pouring buffering material between the primary support and the secondary lining, does not need to erect a support, does not need a lining trolley, has simple equipment, low cost and convenient construction.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel engineering, in particular, to a tunnel inner buffer material horizontal injection pouring laying method and laying structure. BACKGROUND

[0002] For a tunnel crossing an active fault, the expansion amount needs to be determined according to the activity of the fault, and a buffer material is used for filling. The buffer material is generally filled between the initial support and the secondary lining in the tunnel. Currently, the commonly used buffer material is foam concrete. Since the foam concrete buffer material is constructed, the initial support has been constructed, but the secondary lining has not been constructed, so that the foam concrete (buffer material) located between the initial support and the secondary lining is difficult to lay.

[0003] In the prior art, someone proposes to use a lining trolley to complete the laying of the foam concrete, such as the Chinese patent application with the application number 201210019772.0, which discloses a tunnel foam concrete damping structure and a construction method thereof. A buffer layer is arranged between the inner layer and the outer layer of the tunnel arch and the side wall. The inner layer is an initial support layer, which includes a steel arch and a steel mesh. The outer layer is a secondary lining layer. The buffer layer is a foam concrete layer. The connecting steel bars are welded on the outer side of the steel mesh of the initial support layer. The connecting steel bars are uniformly distributed along the tunnel arch and the side wall in the circumferential direction, and the connecting steel bars are uniformly and spacedly distributed on the steel mesh in the tunnel mileage direction. The length of the connecting steel bars of the connecting steel bars is set to extend into the foam concrete layer. At the same time, it is further disclosed that a lining trolley and a foaming machine are used to produce foam concrete by the foaming machine. The pouring of the foam concrete layer is performed through the reserved holes of the trolley template. After the foam concrete layer is constructed, the secondary lining layer is constructed.

[0004] However, for a TBM tunnel, due to the limitation of the construction process, the secondary lining can only be poured through the whole tunnel, but the buffer layer needs to be laid in advance at the active fault, so the traditional secondary lining trolley cannot be used. In addition, if the secondary lining trolley is used for pouring, the secondary lining trolley needs to have the function of section change, or the trolley needs to be modified, which is difficult and expensive. SUMMARY

[0005] In view of the defects in the prior art, the purpose of the present application is to provide a tunnel inner buffer material horizontal injection pouring laying method and laying structure.

[0006] According to one aspect of the present application, a tunnel inner foam concrete horizontal injection laying method is provided, the foam concrete is laid between the initial support and the secondary lining in the tunnel, and the method comprises the following steps:

[0007] A plurality of steel formworks are installed inside the initial support in the tunnel, adjacent steel formworks are fixed by bolt connection, and the plurality of steel formworks are sequentially connected to form a formwork whole, a space is formed between the formwork whole and the initial support, and the space is used for laying the foam concrete; the shape of the formwork whole matches the initial support;

[0008] A steel formwork end is installed on the steel formwork at the end of the formwork whole, and the steel formwork at the end is located at the top position in the tunnel, at least one pouring opening is provided on the steel formwork end, and the pouring opening communicates with the space;

[0009] Foam concrete is horizontally sprayed into the space from the pouring opening of the top steel formwork, and the foam concrete is poured and formed from bottom to top;

[0010] After the foam concrete reaches the set strength, the steel formwork is removed.

[0011] Preferably, the steel formwork is a prefabricated steel structure, wherein a bolt hole is provided around each steel formwork, and two adjacent steel formworks are connected by inserting a bolt through the bolt hole.

[0012] Preferably, the steel formwork end is a plate perpendicular to the main body of the steel formwork, and the plate and the main body of the steel formwork are connected by a bolt.

[0013] Preferably, the steel formwork is provided with one or more stiffening ribs, including transverse stiffening ribs and / or longitudinal stiffening ribs, for improving the pressure bearing capacity of the steel formwork.

[0014] According to a second aspect of the present application, a foam concrete horizontal spraying and laying structure in a tunnel is provided, which comprises:

[0015] A plurality of steel formworks are installed inside the initial support in the tunnel, adjacent steel formworks are fixed by bolt connection, and the plurality of steel formworks are sequentially connected to form a formwork whole, a space is formed between the formwork whole and the initial support, and the space is used for laying the foam concrete; the shape of the formwork whole matches the initial support;

[0016] A steel formwork end is installed on the steel formwork at the end of the formwork whole, and the steel formwork at the end is located at the top position in the tunnel, at least one pouring opening is provided on the steel formwork end, and the pouring opening communicates with the space;

[0017] Foam concrete is horizontally sprayed into the space from the pouring opening of the top steel formwork, and the foam concrete is poured and formed from bottom to top.

[0018] Compared with the prior art, the embodiments of the present invention have at least one of the following beneficial effects:

[0019] This invention provides a method for horizontal spraying of foamed concrete in tunnels. It utilizes reusable steel formwork for support according to the required excavation volume, and then horizontally sprays foamed concrete onto the top of the tunnel through the pouring port on the steel formwork to complete the pouring of foamed concrete. This method solves the problem of pouring the buffer material (foamed concrete) between the initial support and the secondary lining.

[0020] The steel formwork of the present invention is a prefabricated steel structure that does not require the erection of supports or the use of lining trolleys. The equipment is simple, the cost is low, and the construction is convenient.

[0021] This invention provides a method for horizontal spraying of foamed concrete in tunnels, which involves horizontally spraying foamed concrete from the top of the tunnel through pre-reserved holes, thereby achieving the bottom-up casting and molding of foamed concrete. The foamed concrete is subjected to gravity, resulting in good compactness and high molding quality. Attached Figure Description

[0022] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0023] Figure 1 This is a schematic diagram illustrating the principle of horizontal spraying of foamed concrete in a tunnel according to one embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram of a horizontal spraying structure for foamed concrete in a tunnel according to one embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of a steel formwork in one embodiment of the present invention;

[0026] Figure 4a This is a schematic diagram of the connection between two non-end steel templates in one embodiment of the present invention;

[0027] Figure 4b This is a schematic diagram of the connection between the steel template and the end of the steel template in one embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of the steel template end splicing structure in one embodiment of the present invention;

[0029] Figure 6 This is a schematic diagram of the stiffening ribs of the steel template in one embodiment of the present invention.

[0030] In the diagram: 1 is the surrounding rock, 2 is the initial support, 3 is the secondary lining, 4 is the steel formwork, 5 is the foamed concrete, 6 is the end of the steel formwork, 7 is the bolt, 8 is the pouring port, 9 is the stiffening rib, 10 is the splice joint, 11 is the bolt hole, and 12 is the plain concrete. Detailed Implementation

[0031] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0032] Because the initial support has been completed but the secondary lining has not yet been constructed when the foamed concrete buffer material is laid, it is difficult to lay the foamed concrete (buffer material) located between the initial support and the secondary lining. To address the above problem, this invention provides a method for horizontal spraying of foamed concrete in tunnels, wherein the foamed concrete 5 is laid between the initial support 2 and the secondary lining 3 in the tunnel.

[0033] Reference Figure 1 As shown in the figure, this embodiment provides a method for horizontal spraying of foamed concrete in tunnels. Multiple spliced ​​steel templates are used for support, forming a space for foamed concrete laying between them and the initial support. Horizontal spraying is then used to complete the horizontal spraying of foamed concrete in the tunnel.

[0034] Specifically, the method for horizontal spraying of foamed concrete inside the tunnel can be referred to in the following steps:

[0035] S1, Install steel formwork:

[0036] like Figure 1 As shown, the surrounding rock 1 is a tunnel. The initial support 2 is constructed first in the tunnel. Then, multiple steel formwork 4 are installed on the inner side of the initial support 2. Adjacent steel formwork 4 are connected and fixed by bolts 7. After multiple steel formwork 4 are connected in sequence, they form a template whole. A space is formed between the template whole and the initial support 2. This space is used to lay foam concrete 5.

[0037] Specifically, the overall cross-sectional shape of the connected template matches the cross-sectional shape of the initial support 2, such as... Figure 2 As shown, the cross-sectional shape of the initial support 2 is similar to an ellipse, and the overall cross-sectional shape of the template is also similar to an ellipse. Because it is located inside the initial support 2, the inner diameter of the template is smaller than that of the initial support 2. In this example embodiment, the steel template 4 is arc-shaped.

[0038] Of course, this is only one embodiment of the present invention. In other embodiments, the cross-sectional shape of the initial support 2 can also be other shapes, and the cross-sectional shape of the template as a whole is also adjusted accordingly.

[0039] The specific size of the space formed between the above-mentioned template and the initial support 2 is determined according to the actual engineering design. This space determines the amount of foamed concrete 5 that needs to be laid.

[0040] like Figure 2 As shown, after the plain concrete 12 is poured, it can be used as a support for installing the steel formwork 4. The entire structure installation does not require other supports or equipment, simplifying construction and greatly reducing complexity.

[0041] S2, Install steel formwork end 6. The steel formwork end 6 is installed on the steel formwork 4 at the end of the formwork body, and the steel formwork 4 at the end is located at the top of the tunnel. At least one pouring port 8 is preset on the steel formwork end 6. The pouring port 8 is connected to the space formed between the formwork body and the initial support 2.

[0042] In this embodiment, the pouring port 8 is not set on each steel formwork. Instead, after all the steel formwork 4 are connected into a whole, the pouring port 8 is only set on the end 6 of the steel formwork located at the top of the tunnel and belonging to the whole formwork. That is, the pouring port 8 is located on the end 6 of the highest steel formwork. In this way, gravity can be used to form the foamed concrete in the subsequent pouring.

[0043] At least one pouring opening 8 should be provided on the end 6 of the steel formwork, as per [reference]. Figure 5 As shown, three pouring inlets 8 are located on the highest end 6 of the steel formwork. Of course, to improve pouring efficiency, more pouring inlets 8 can be installed, depending on the actual pouring volume. If there are multiple pouring inlets 8, they can be arranged evenly in parallel and at intervals, with all inlets 8 communicating with the aforementioned space.

[0044] S3, Foamed concrete is horizontally sprayed into the space from the pouring port 8 of the top steel formwork, and the foamed concrete is poured from bottom to top to form the shape.

[0045] In this step, a horizontal spray pipe can be used inside the pouring port 8 to spray foamed concrete horizontally into the space. In this way, the foamed concrete sprayed horizontally from the pouring port 8 at the end 6 of the steel formwork set on the top steel formwork 4 can achieve the foamed concrete to be poured and formed from bottom to top. The foamed concrete is subjected to gravity, has good compactness, and has high forming quality.

[0046] S4. After the foamed concrete reaches the set strength, remove the steel formwork.

[0047] In this step, foamed concrete is horizontally poured into the top of the tunnel. Depending on the engineering design requirements, such as after 7-10 days of pouring to reach the set strength, the steel formwork 4 can be removed. After the foamed concrete reaches its strength, the steel formwork 4 is removed, and the secondary lining 3 can be constructed simultaneously to complete the final buffer material filling structure.

[0048] The above embodiments of the present invention can solve the problem of pouring the buffer material (foamed concrete) between the initial support and the secondary lining. Using steel formwork for support eliminates the need for scaffolding and lining trolleys, resulting in simple equipment, low cost, and convenient construction.

[0049] Reference Figure 3 and 4a As shown in 4b, in some embodiments, the steel formwork 4 adopts a prefabricated steel structure, wherein each steel formwork 4 has multiple bolt holes 11 around its perimeter. See also Figure 4a As shown, the two non-end steel templates are connected, and the two adjacent steel templates 4 are connected to each other by inserting the corresponding bolts 7 into each bolt hole 11.

[0050] In this embodiment, the quantity and size of the steel formwork 4 are determined based on the area of ​​foamed concrete to be laid within the tunnel (initial support). The steel formwork 4 adopts a regular shape, preferably using rectangular (square) steel plates formed to fit the shape of the tunnel (initial support). Multiple steel formwork 4s can use the same size, facilitating manufacturing and installation. For example, in some embodiments, 3m × 3m steel formwork 4 can be used. Additionally, as... Figure 1 As shown, from the longitudinal section of the tunnel (initial support), the steel formwork 4 can be an array-type continuous connection structure, and the specific number and length of the connections are determined according to the project requirements.

[0051] Reference Figure 4b The diagram shown is a schematic representation of the connection between the steel template and the steel template end in one embodiment of the present invention. A steel template end 6 connected by bolts is provided at the outermost end of the template body. The steel template end 6, the steel template 4, and the tunnel (initial support) cooperate to form a relatively sealed space, which can effectively prevent foam concrete leakage after spraying.

[0052] The steel formwork end 6 can be selected from various structural forms. For example, as shown in Figure 4, in a preferred embodiment, the steel formwork end 6 can be a plate-shaped member perpendicular to the main body of the steel formwork. One end of the plate-shaped member is connected to the main body of the steel formwork by bolts, and the other end is detachably connected and fixed to the tunnel (initial support). This avoids leakage of foamed concrete and facilitates the subsequent disassembly and reuse of the formwork.

[0053] Reference Figure 2As shown, there is a joint (joint 10 in the figure) between two adjacent steel formwork 4 (including the steel formwork ends 6 installed thereon). In other embodiments, to further prevent foamed concrete leakage, a sealing component can be provided at the joint (joint 10 in the figure). The sealing component can be an elastic gasket, such as a rubber gasket, or other forms.

[0054] In another preferred embodiment, to accommodate tunnels with larger cross-sectional areas (initial support) and ensure the stability of the steel formwork structure, one or more stiffening ribs can be provided on a single steel formwork. Depending on the shape and size of the steel formwork and the structural stability requirements, the stiffening ribs can be provided only as transverse stiffening ribs, only as longitudinal stiffening ribs, or as shown in the following examples. Figure 6 As shown, both transverse and longitudinal stiffening ribs are installed on the steel formwork. These stiffening ribs are used to increase the load-bearing capacity of the steel formwork. Multiple transverse and longitudinal stiffening ribs can be installed at equal intervals, and should be positioned as perpendicular as possible to the steel formwork 4. The transverse and longitudinal stiffening ribs intersect to form a cross shape, thus creating a stable reinforced structure. The specific number and size of the stiffening ribs should ensure structural stability without affecting the laying of foamed concrete between the formwork and the initial support 2.

[0055] In the above embodiment, multiple steel formwork 4 are installed on the inner side of the initial support 2 to... Figure 5 Taking the example shown, the bottom steel formwork 4 can be installed first, followed by the side steel formwork 4s on both sides of the bottom steel formwork 4, and finally the top steel formwork 4. Of course, if the structure allows, the bottom steel formwork 4 can also be installed first, followed by the side steel formwork 4 on one side of the bottom steel formwork 4, then the top steel formwork 4, and finally the side steel formwork 4 on the other side of the bottom steel formwork 4.

[0056] The horizontal spraying method for foamed concrete in tunnels provided in the above embodiments of the present invention utilizes reusable steel templates to horizontally spray foamed concrete onto the top of the tunnel to complete the pouring of foamed concrete. It does not require complex support setup or lining trolleys, and the equipment is simple, greatly reducing construction costs and simplifying construction steps.

[0057] This invention provides a method for horizontal spraying of foamed concrete in tunnels, which involves horizontally spraying foamed concrete from the top of the tunnel through pre-reserved holes, thereby achieving the bottom-up casting and molding of foamed concrete. The foamed concrete is subjected to gravity, resulting in good compactness and high molding quality.

[0058] Based on the same technical concept as the above embodiments, in another embodiment of the present invention, a horizontal spraying structure for foamed concrete in tunnels is also provided to realize the horizontal spraying of foamed concrete in tunnels as described in the above embodiments. Specifically, the horizontal spraying structure for foamed concrete in tunnels includes:

[0059] Multiple steel formwork 4 are installed inside the initial support in the tunnel. Adjacent steel formwork is fixed by bolts. Multiple steel formwork 4 are connected in sequence to form a formwork assembly. This formwork assembly and the initial support 2 form a space for laying foamed concrete. The shape of the formwork assembly matches the initial support.

[0060] The steel formwork end 6 is installed on the steel formwork 4 at the end of the formwork body, and the steel formwork 4 at this end is located at the top of the tunnel. The steel formwork end 6 has one or more pre-set pouring ports 8, which are connected to the space formed between the formwork body and the initial support 2. Foamed concrete is horizontally sprayed into the space through a horizontal spraying pipe, and the foamed concrete is poured from bottom to top to form the shape.

[0061] Foamed concrete was poured horizontally at the top of the tunnel. After the foamed concrete reached its strength, the steel formwork 4 was removed, and the secondary lining was constructed simultaneously to finally complete the foamed concrete laying work.

[0062] The structures of the various components involved in this embodiment are the same as those in the above-described method for horizontal spraying of foamed concrete in tunnels, and will not be described again here.

[0063] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention. The above preferred features can be used in any combination without conflict.

Claims

1. A method for horizontal spraying of foamed concrete in a tunnel, wherein the foamed concrete, after being laid, is located between the initial support and the secondary lining within the tunnel, characterized in that... include: Multiple steel formwork templates are installed on the inner side of the initial support inside the TBM tunnel. Adjacent steel formwork templates are fixed together by bolts. Multiple steel formwork templates are connected in sequence to form a template assembly. A space is formed between the template assembly and the initial support, and the space is used to lay the foamed concrete. The shape of the template assembly matches the initial support. Install steel formwork end caps, which are installed on the steel formwork at the end of the entire formwork, and the steel formwork at this end is located at the top of the tunnel. At least one pouring port is pre-set on the steel formwork end cap, and the pouring port communicates with the space. Foamed concrete is horizontally sprayed into the space from the pouring port of the top steel formwork, and the foamed concrete is poured from bottom to top to form the shape. After the foamed concrete reaches the set strength, the steel formwork is removed; The entire process of laying the foamed concrete requires no support frame or lining trolley.

2. The method for horizontal spraying of foamed concrete in tunnels according to claim 1, characterized in that, The steel template is a prefabricated steel structure, wherein each steel template has bolt holes around its perimeter, and adjacent steel templates are connected by inserting bolts into these bolt holes.

3. The method for horizontal spraying of foamed concrete in tunnels according to claim 1, characterized in that, The end of the steel template is a plate-shaped component perpendicular to the main body of the steel template, and the plate-shaped component is bolted to the main body of the steel template.

4. The method for horizontal spraying of foamed concrete in tunnels according to claim 1, characterized in that, The steel formwork is provided with one or more stiffening ribs, including transverse stiffening ribs and / or longitudinal stiffening ribs, for improving the load-bearing capacity of the steel formwork.

5. The method for horizontal spraying of foamed concrete in tunnels according to claim 1, characterized in that, Multiple steel formwork templates are installed on the inner side of the initial support, wherein: first, the lower steel formwork template located at the bottom of the tunnel is installed, then the side steel formwork templates located on both sides of the lower steel formwork template are installed, and finally the top steel formwork template is installed.

6. The method for horizontal spraying of foamed concrete in tunnels according to claim 1, characterized in that, There is a splice joint at the connection between adjacent steel formworks, and a sealing component is installed at the splice joint to prevent the foamed concrete from leaking out.

7. The method for horizontal spraying of foamed concrete in tunnels according to claim 1, characterized in that, The quantity and size of the steel templates are determined based on the area of ​​foamed concrete that needs to be laid inside the tunnel.

8. A horizontal spraying structure for foamed concrete in tunnels, used in the horizontal spraying method for foamed concrete in tunnels as described in claim 1, characterized in that, include: Multiple steel formwork panels are installed inside the initial support of the tunnel. Adjacent steel formwork panels are fixed together by bolts. The multiple steel formwork panels are connected in sequence to form a template assembly. A space is formed between the template assembly and the initial support, and the space is used to lay the foamed concrete. The shape of the template assembly matches the initial support. The steel formwork end is installed on the steel formwork at the end of the formwork assembly, and the steel formwork at this end is located at the top of the tunnel. At least one pouring port is preset on the steel formwork end, and the pouring port communicates with the space. Foamed concrete is horizontally sprayed into the space through a horizontal spray pipe, and the foamed concrete is poured and formed from bottom to top.

9. The horizontal spraying structure for foamed concrete in tunnels according to claim 8, characterized in that, Also includes: The steel template is a prefabricated steel structure, wherein each steel template has bolt holes around its perimeter, and adjacent steel templates are connected by inserting bolts into these bolt holes.

10. The horizontal spraying structure for foamed concrete in tunnels according to claim 8, characterized in that, The end of the steel template is a plate-shaped component perpendicular to the main body of the steel template, and the plate-shaped component is bolted to the main body of the steel template. The steel formwork is provided with one or more stiffening ribs, including transverse stiffening ribs and / or longitudinal stiffening ribs, for improving the load-bearing capacity of the steel formwork.

Images