Undercut excavation construction of existing station through-hole type Built-in steel box structure of top plate

Abstract

To provide a built-in steel box structure for an undercut excavation construction top plate of an existing pass-through type station, which avoids the use of a jack, further avoids the obstruction of the binding connection of reinforcing bars, ensures the continuity and completeness of the reinforcing bars in concrete, does not affect the load-bearing state of the entire lining, and is less likely to cause cracks. [Solution] The built-in steel box structure of the top plate of an undercut excavation construction of an existing station through-passage type includes an existing tunnel 1, a new tunnel 11 is excavated at the bottom of the existing tunnel, reinforcing piles 12 are fixedly connected to the surface of the new tunnel, and a steel box structure body is installed on the surface of the reinforcing piles, and the steel box structure body includes a support plate, which is welded to the top of the reinforcing pile.

Description

[Technical field]

[0001] This invention relates to the technical field of tunnel construction, and more particularly to the built-in steel box structure of the undercut excavation top plate of a tunnel-type existing station. [Background technology]

[0002] In the undercut excavation construction of existing stations, in order to ensure the structural safety of the existing stations, the construction process requires the station to be supported by support piles. After the construction of the support piles is completed, it is often necessary to use structures such as jacks to transition and connect them, thereby adjusting and maintaining the bearing capacity. However, after the undercut excavation is completed, when the top lining is constructed, jacks must be driven into the lining, which will block the binding connection of the reinforcing bars in the lining and once again affect the load-bearing state of the entire lining, making it easy for cracks to occur. Summary of the Invention [Problem to be solved by the invention]

[0003] The purpose of this invention is to provide a built-in steel box structure for the undercut excavation construction top plate of an existing pass-through type station, in order to solve the problem that when constructing the conventional top lining proposed in the background art above, a jack needs to be driven into the lining, which blocks the binding connection of the reinforcing bars in the lining, affects the load-bearing state of the entire lining, and makes it easy for cracks to occur. [Means for solving the problem]

[0004] In order to achieve the above object, the present invention provides the following technical solution: The built-in steel box structure of the top plate of the undercut excavation construction of the existing station through-passing includes an existing tunnel, a new tunnel is excavated at the bottom of the existing tunnel, a reinforcing pile is fixedly connected to the surface of the new tunnel, a steel box structure body is installed on the surface of the reinforcing pile, the steel box structure body includes a support plate, the support plate is welded to the top of the reinforcing pile, two sets of the support plate are installed, a connecting web plate is fixedly connected between the two sets of support plates, and the top support plate is connected in contact with the bottom of the existing tunnel, rebar holes are drilled on the surface of the connecting web plate, vertical rebars are drilled and connected on the rebar holes, multiple sets of the connecting web plate are installed, horizontal rebars are placed between the multiple sets of connecting web plates, and a lining is cast inside the new tunnel, and the top of the lining covers the steel box structure body and the top of the reinforcing pile.

[0005] Preferably, a plurality of sets of the reinforcing piles are installed, the bottoms of the reinforcing piles are installed at the bottom of the new tunnel, and the reinforcing piles support the steel box structure body on the new tunnel.

[0006] Preferably, the support plates and the rebar holes are perpendicular to each other, the rebar holes are installed in multiple sets, and the multiple sets of rebar holes are linearly and uniformly arranged between the two sets of support plates.

[0007] Preferably, the rebar holes are arranged in three sets, the longitudinal rebars are arranged in three sets, and the three sets of longitudinal rebars correspond to the three sets of rebar holes.

[0008] Preferably, the longitudinal bars pass through the rebar holes and at the same time through a plurality of sets of tie web plates, which support the longitudinal bars on the steel box structure body.

[0009] Preferably, the support plates, connecting web plates and longitudinal bars form a plurality of sets of mesh holes on the steel box structure body, and the transverse bars pass through the mesh holes in the steel box structure body.

[0010] Preferably, the vertical reinforcing bars and the horizontal reinforcing bars are perpendicular to each other, the horizontal reinforcing bars are installed in multiple sets, and the multiple sets of horizontal reinforcing bars and the vertical reinforcing bars are not located in the same horizontal plane. Effect of the Invention

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0012] 1. Reinforcement piles are driven into the bottom of the existing tunnel, then a new tunnel is excavated, the steel box structure body is welded to the top of the reinforcing piles, and the vertical rebars are connected to pass through the reinforcing bar holes on the connecting web plate. At this time, the support plate, the connecting web plate and the vertical rebars form multiple sets of mesh holes on the steel box structure body, and the horizontal rebars pass through the mesh holes in the steel box structure body to bind and connect the multiple sets of horizontal rebars. Then, the lining is cast into the new tunnel, and the top of the lining covers the steel box structure body and the top of the reinforcing piles. After the lining is fixed, the reinforcing piles are cut and removed inside the new tunnel. This steel box structure avoids the use of jacks and the blocking of the binding and connection of the reinforcing bars, ensures the continuity and integrity of the reinforcing bars in the concrete, does not affect the load-bearing state of the entire lining, and is not prone to cracks. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a schematic front sectional view of the structure of the present invention; [Diagram 2] FIG. 2 is an enlarged schematic diagram of the structure of the present invention shown in FIG. [Diagram 3] 1 is a schematic front sectional perspective view of the steel box structure body structure of the present invention; [Figure 4] FIG. 2 is a schematic front cross-sectional perspective view of the steel box structure main body assembly rebar of the present invention; [Diagram 5] FIG. 5 is an enlarged schematic diagram of the structure of B in FIG. 4 of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] An embodiment of the present invention will be described with reference to Figs. 1 to 5.

[0015] The built-in steel box structure of the undercut excavation construction top plate of the existing station includes an existing tunnel 1, a new tunnel 11 is excavated at the bottom of the existing tunnel 1, reinforcing piles 12 are fixedly connected to the surface of the new tunnel 11, a steel box structure body 2 is installed on the surface of the reinforcing piles 12, the steel box structure body 2 includes a support plate 21, the support plate 21 is welded to the top of the reinforcing piles 12, the support plate 21 is installed in two sets, and a connecting weld is provided between the two sets of support plates 21. The connecting web plates 22 are fixedly connected, and the top support plate 21 is in contact with and connected to the bottom of the existing tunnel 1, reinforcing bar holes 23 are drilled on the surface of the connecting web plates 22, vertical reinforcing bars 24 are drilled into the reinforcing bar holes 23 and connected, multiple sets of connecting web plates 22 are installed, horizontal reinforcing bars 25 are placed between the multiple sets of connecting web plates 22, and a lining 3 is poured into the inside of the new tunnel 11, and the top of the lining 3 covers the steel box structure main body 2 and the tops of the reinforcing piles 12.

[0016] Furthermore, multiple sets of reinforcement piles 12 are installed, the bottoms of the reinforcement piles 12 are installed at the bottom of the new tunnel 11, and the reinforcement piles 12 support the steel box structure main body 2 on the new tunnel 11; the reinforcement piles 12 are attached from the bottom of the existing tunnel 1 before excavating the reinforcement piles 12, and the reinforcement piles 12 have a certain height, so that the reinforcement piles 12 can be deeply inserted a certain distance into the bottom of the new tunnel 11; and the tops of the reinforcement piles 12 can support the steel box structure main body 2 at the top of the new tunnel 11.

[0017] Furthermore, the support plates 21 and the reinforcing bar holes 23 are perpendicular to each other, the reinforcing bar holes 23 are installed in multiple sets, and the multiple sets of reinforcing bar holes 23 are linearly arranged evenly between the two sets of support plates 21, and the support plates 21 and the connecting web plates 22 ensure the stability of the entire structure of the steel box structure main body 2.

[0018] Furthermore, three sets of reinforcing bar holes 23 are installed, three sets of vertical reinforcing bars 24 are installed, the three sets of vertical reinforcing bars 24 correspond to the three sets of reinforcing bar holes 23, and the three sets of vertical reinforcing bars 24 are drilled onto and connected to the three sets of reinforcing bar holes 23, respectively.

[0019] Furthermore, the vertical reinforcing bars 24 pass through the reinforcing bar holes 23 and at the same time penetrate multiple sets of connecting web plates 22, and the connecting web plates 22 support the vertical reinforcing bars 24 on the steel box structure main body 2, thereby making it easy to assemble the vertical reinforcing bars 24.

[0020] Furthermore, the support plates 21, the connecting web plates 22 and the vertical reinforcement bars 24 form multiple sets of mesh holes on the steel box structural body 2, and the horizontal reinforcement bars 25 pass through the mesh holes of the steel box structural body 2, at which time the horizontal reinforcement bars 25 and the vertical reinforcement bars 24 can be bound and connected to each other, and the positions of the horizontal reinforcement bars 25 and the vertical reinforcement bars 24 are ensured.

[0021] Furthermore, the vertical reinforcing bars 24 and the horizontal reinforcing bars 25 are perpendicular to each other, the horizontal reinforcing bars 25 are installed in multiple sets, and the multiple sets of horizontal reinforcing bars 25 and vertical reinforcing bars 24 are not located on the same horizontal plane. After the assembly of the horizontal reinforcing bars 25 and the vertical reinforcing bars 24 in the steel box structure main body 2 is completed, the lining 3 is poured, and the lining 3 is poured from the bottom to the top inside the new tunnel 11.

[0022] Working principle: Reinforcement piles 12 are driven into the bottom of the existing tunnel 1, then a new tunnel 11 is excavated, and the steel box structure body 2 is welded to the top of the reinforcement piles 12. Then, the vertical reinforcing bars 24 are connected to the connecting web plate 22 so as to penetrate the reinforcing bar holes 23 on the connecting web plate 22. At this time, the support plate 21, the connecting web plate 22 and the vertical reinforcing bars 24 form multiple sets of mesh holes on the steel box structure body 2, and the horizontal reinforcing bars 25 are made to penetrate the mesh holes of the steel box structure body 2, and the multiple sets of horizontal reinforcing bars 25 and vertical reinforcing bars 24 are tied and connected, then the lining 3 is poured into the inside of the new tunnel 11, the top of the lining 3 covers the steel box structure body 2 and the tops of the reinforcing piles 12, and after the lining 3 is fixed, the reinforcing piles 12 are cut and removed inside the new tunnel 11. This steel box structure avoids the use of jacks, and also avoids the obstruction of the tying and connection of the reinforcing bars, ensures the continuity and completeness of the reinforcing bars in the concrete, does not affect the load-bearing state of the entire lining 3, and is less likely to cause cracks. [Explanation of symbols]

[0023] 1 Existing tunnel 11 New Tunnel 12 Reinforcement piles 2 Steel box structure body 21 Support plate 22 Connecting web plate 23 Rebar hole 24 Longitudinal reinforcement 25 Transverse Reinforcement 3 Lining

Claims

1. 1. A built-in steel box structure of an undercut excavation construction top plate of an existing station of a pass-through type, comprising an existing tunnel at the bottom of which a new tunnel is excavated, characterized in that: reinforcing piles are fixedly connected to a surface of the new tunnel, a steel box structure body is installed on the surface of the reinforcing piles, the steel box structure body includes a support plate, the support plate is welded to the top of the reinforcing piles, the support plate is installed in two sets, a connecting web plate is fixedly connected between the two sets of support plates, and the top support plate is connected in contact with the bottom of the existing tunnel, reinforcing bar holes are drilled on the surface of the connecting web plate, and vertical reinforcing bars are drilled and connected on the reinforcing bar holes, the connecting web plate is installed in multiple sets, and horizontal reinforcing bars are placed between the multiple sets of connecting web plates, and a lining is cast inside the new tunnel, and the top of the lining covers the steel box structure body and the top of the reinforcing piles.

2. The built-in steel box structure of the undercut excavation construction top plate of the pass-through type existing station according to claim 1, characterized in that the reinforcement piles are installed in multiple sets, the bottoms of the reinforcement piles are installed at the bottom of the new tunnel, and the reinforcement piles support the steel box structure body on the new tunnel.

3. The built-in steel box structure of the undercut excavation construction top plate of the pass-through existing station as described in claim 1, characterized in that the support plate and the reinforcing bar holes are perpendicular to each other, the reinforcing bar holes are installed in multiple sets, and the multiple sets of reinforcing bar holes are linearly and uniformly arranged between the two sets of support plates.

4. The built-in steel box structure of the undercut excavation construction top plate of the pass-through existing station as described in claim 1, characterized in that the rebar holes are installed in three sets, the vertical rebars are installed in three sets, and the three sets of vertical rebars correspond to the three sets of rebar holes.

5. The built-in steel box structure of the undercut excavation construction top plate of the pass-through type existing station according to claim 4, characterized in that the vertical rebars pass through the rebar holes and at the same time penetrate multiple sets of connecting web plates, and the connecting web plates support the vertical rebars on the steel box structure body.

6. The built-in steel box structure of the undercut excavation construction top plate of the pass-through type existing station as claimed in claim 1, characterized in that the support plate, the connecting web plate and the vertical reinforcing bars form a plurality of sets of mesh holes on the steel box structure body, and the horizontal reinforcing bars pass through the mesh holes of the steel box structure body.

7. The built-in steel box structure of the undercut excavation construction top plate of the existing station according to claim 6, characterized in that the vertical reinforcing bars and the horizontal reinforcing bars are perpendicular to each other, the horizontal reinforcing bars are installed in multiple sets, and the multiple sets of horizontal reinforcing bars and the vertical reinforcing bars are not located on the same horizontal plane.

Images