CN118008366A - A steel-concrete composite lattice shell segment - Google Patents

Abstract

The invention relates to a steel-concrete combined reticulated shell type duct piece, which comprises a plurality of duct piece connecting blocks spliced with each other, wherein each duct piece connecting block comprises a reticulated shell and a concrete piece, and a first bolt ball is arranged on the inner wall of the concrete piece; the first bolt ball is fixed through the support and the reinforcing mesh of the concrete sheet, and the net shell is fixed on the inner side of the concrete sheet through the first bolt ball; the pipeline inside the tunnel is arranged in the range of the net shell in a penetrating way. The beneficial effects of the invention are as follows: the combined structure stress principle is utilized, and part of concrete layers on the inner sides of the duct pieces are replaced through the net shells, so that the thickness of the concrete parts is reduced compared with that of the conventional duct pieces while the design requirements are met, and the dead weight of the concrete pieces is reduced; meanwhile, the performance of tension and concrete compression of the structural steel is fully exerted, the bearing capacity is high, the overall stability is good, and the overall strength of the duct piece is increased; the duct piece is prefabricated in a factory and transported to a construction site for assembly, and a first bolt ball is preset during construction of the concrete layer and used for subsequent construction of the net shell, so that post-punching of the concrete layer is avoided.

Description

A steel-concrete composite lattice shell segment

Technical Field

The invention belongs to the field of tunnel shield, and in particular relates to a steel-concrete combined lattice shell type segment.

Background technique

The shield tunnel segment is the innermost barrier of the shield tunnel, bearing the soil pressure and groundwater pressure, and is the main accessory for shield tunnel construction. The development of shield tunnel segments at home and abroad has a long history. Most of the segments are reinforced concrete structures, which have problems such as heavy self-weight and low adjacent waterproof performance.

CN113586084A proposes a prefabricated double-layer segment structure, in which two layers of concrete are poured through a steel structure. After the outer UHPC protective layer is poured, part of the steel bars are exposed to the outside for pouring ordinary concrete layers, which is equivalent to replacing part of the ordinary concrete with the UHPC protective layer, thereby reducing the deadweight of the segment. However, since two pourings are required, the construction efficiency is low and the construction difficulty is relatively large.

Therefore, a new segment structure is urgently needed to solve the above problems.

Summary of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide a steel-concrete composite lattice shell segment.

The steel-concrete composite lattice shell segment comprises a plurality of segment connection blocks spliced together, each segment connection block comprises a lattice shell and a concrete segment, arc-shaped bolt holes are provided at both ends of the concrete segment, the concrete segment is in an arc shape, and a No. 1 bolt ball is provided on the inner wall of the concrete segment;

The No. 1 bolt ball is fixed through the support and the steel mesh of the concrete sheet, the support includes a support pad and a support anchor bar, the No. 1 bolt ball is fixed to the support pad, and the support pad is fixed through the support anchor bar and the steel mesh;

The grid shell includes horizontal bars and oblique bars, which are connected by No. 2 bolt balls, and the grid shell is fixed to the inner side of the concrete sheet by No. 1 bolt balls; the internal pipelines of the tunnel are laid within the range of the grid shell;

The ends of the segment connection blocks are double-layered, the connection seams formed by adjacent segment connection blocks are staggered in double layers, steel plates are embedded at both ends of the concrete sheet, and the adjacent segment connection blocks are connected by arc bolts and straight bolts penetrating the steel plates.

Preferably, arc-shaped bolt holes are also provided on the steel sheet, the lower end of the steel sheet extends out of the concrete sheet, and straight bolt holes are reserved; the straight bolts penetrate the straight bolt holes on two adjacent steel sheets for fixing; the arc-shaped bolt holes are provided in the innermost layer of the double layer of the corresponding connection seam between the end of the concrete sheet and the steel sheet.

Preferably, the lattice shell is made of steel, aluminum alloy, carbon fiber or fiberglass, and is a cross truss system, a tetrahedral pyramid system, a triangular pyramid system or a curved lattice system. When the lattice shell is a tetrahedral pyramid system, the angle of the oblique rod in the tetrahedral pyramid is 30° to 60°.

Preferably, the No. 1 bolt ball is provided with a rod hole and a center axis hole, the support plate is provided with a center axis and a clamping plate, the center axis is inserted into the center axis hole, the clamping plate is clamped on the No. 1 bolt ball, and the rod hole is used to insert the ends of the flat rod and the inclined rod.

Preferably, the steel mesh includes transverse steel bars, longitudinal steel bars and stirrups, and the steel plates are arranged at the ends of the steel mesh through steel plate anchor bars.

The construction method of the steel-concrete composite lattice shell segment comprises the following steps:

Step 1: Tie the steel mesh and set the support for the steel plate and the No. 1 bolt ball, install the No. 1 bolt ball through the support, and pour the concrete sheet;

Step 2: Assemble the straight rods, inclined rods and No. 2 bolt balls to form the grid shell in each segment connection block, and assemble the grid shell and concrete sheet through the No. 1 bolt balls to complete the assembly of all segment connection blocks;

Step 3: Connect and fix two adjacent segment connection blocks by using arc bolts and straight bolts, and connect and fix the grid shells of the two segment connection blocks by using additional rods;

Step 4: Lay the internal pipelines of the tunnel inside the grid shell.

Preferably, in step 2 and step 3, two adjacent concrete sheets are first connected and fixed by arc bolts and straight bolts to form concrete pipe segments, and then the straight rods, inclined rods and No. 2 bolt balls are assembled to form an annular grid shell, and the grid shell is fixed to the inner side of the concrete ring by No. 1 bolt balls.

The beneficial effects of the present invention are:

1) The present invention utilizes the force principle of the combined structure and replaces part of the concrete layer on the inner side of the segment with a grid shell. While meeting the design requirements, the thickness of the concrete part is smaller than that of the previous segment, thereby reducing the dead weight of the concrete segment. At the same time, the tensile properties of the structural steel and the compressive properties of the concrete are fully utilized, with high bearing capacity and good overall stability, thereby increasing the overall strength of the segment.

2) The present invention utilizes the characteristics of simple lattice shell structure, low assembly difficulty, and multiple gaps to increase the space utilization rate in the tunnel. In addition, the lattice shell structure has good seismic resistance and can effectively reduce the damage to the structure caused by earthquakes.

3) The present invention adopts an assembled type. The pipe segments are prefabricated in the factory and transported to the construction site for assembly. A No. 1 bolt ball is preset during the construction of the concrete layer for subsequent construction of the grid shell, avoiding the need for post-drilling of the concrete layer, greatly shortening the construction period, saving energy and being environmentally friendly, and having good integrity.

4) The present invention sets the end of the concrete layer as a double-layer structure, so that the connection seams between adjacent pipe segments are double-layer staggered, thereby enhancing the waterproof performance, and pre-buried steel sheets are used to penetrate straight bolts, which, in combination with arc bolts, improve the connection strength between adjacent pipe segments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is an overall schematic diagram of a steel-concrete composite lattice shell segment;

Figure 2 is a schematic diagram of a segment connection block;

Fig. 3 is a schematic diagram of a steel mesh;

Figure 4 is a schematic diagram of a steel plate;

FIG5 is a top view of the No. 1 bolt ball and the support;

FIG6 is a schematic diagram of a support for a No. 1 bolt ball;

Figure 7 is a schematic diagram of an arc-shaped bolt;

Figure 8 is a schematic diagram of a straight bolt;

Fig. 9 is a schematic diagram of a bolt ball No. 1;

Figure 10 is a schematic diagram of the No. 2 bolt ball.

Explanation of the reference numerals in the drawings: segment connecting block 1, grid shell 2, concrete sheet 3, No. 1 bolt ball 4, connecting seam 5, No. 2 bolt ball 6, flat rod 7, inclined rod 8, arc-shaped bolt hole 9, steel mesh 10, transverse steel bar 11, longitudinal steel bar 12, stirrups 13, rod hole 14, bearing pad 15, bearing anchor bar 16, arc-shaped bolt 17, additional rod 18, steel plate 19, steel plate anchor bar 20, straight bolt 21, straight bolt hole 22, thread 23, nut 24, center axis 25, clamping plate 26, center axis hole 27.

Detailed ways

The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for ordinary persons in the art, without departing from the principle of the present invention, the present invention can also be modified in some ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Embodiment 1

As an embodiment, as shown in Figures 1 to 2 and Figures 5 to 10, this steel-concrete composite gridshell type segment includes six segment connection blocks 1 spliced to each other, each segment connection block 1 includes a gridshell 2 and a concrete segment 3, arc-shaped bolt holes 9 are opened at both ends of the concrete segment 3, the concrete segment 3 is in an arc surface shape, and a No. 1 bolt ball 4 is provided on the inner wall of the concrete segment 3.

The No. 1 bolt ball 4 is fixed by the support and the steel mesh 10 of the concrete sheet 3. The support includes a support pad 15 and a support anchor bar 16. The No. 1 bolt ball 4 is fixed on the support pad 15. The support pad 15 is fixed by the support anchor bar 16 and the steel mesh 10. The steel mesh 10 includes transverse steel bars 11, longitudinal steel bars 12 and stirrups 13.

The grid shell 2 includes a flat rod 7 and an oblique rod 8 of uniform thickness, and is evenly stressed. The flat rod 7 and the oblique rod 8 are connected by a No. 2 bolt ball 6. The No. 2 bolt ball 6 has a plurality of rod holes 14 for connecting the flat rod 7 and the oblique rod 8. The grid shell 2 is fixed to the inner side of the concrete sheet 3 by a No. 1 bolt ball 4, giving full play to the tensile properties of structural steel and the compressive properties of concrete, with high bearing capacity and good overall stability. The overall strength of the pipe segment is increased while reducing the amount of concrete used. The thickness of the concrete sheet 3 is much smaller than that of other ordinary reinforced concrete pipe segments, which is only about half of the thickness of the existing pipe segments, so its deadweight is greatly reduced.

The lattice shell 2 is made of steel, aluminum alloy, carbon fiber or fiberglass, and is a cross truss system, a tetrahedral pyramid system, a triangular pyramid system or a curved lattice system, which has good seismic resistance and can effectively reduce the damage to the structure caused by earthquakes. In this embodiment, the lattice shell 2 is a tetrahedral pyramid system, and the angle of the oblique rod 8 in the tetrahedral pyramid is 30° to 60°. The internal pipelines of the tunnel are laid within the scope of the lattice shell 2, which not only improves the utilization rate of the underground space, but also reduces the engineering workload of laying the internal pipelines of the tunnel.

The No. 1 bolt ball 4 is provided with a rod hole 14 and a center axis hole 27, and the support pad 15 is provided with a center axis 25 and a clamping plate 26. The No. 1 bolt ball 4 is fixed to the support through the support center axis 25 and the clamping plate 26. Specifically, as shown in FIG. 5 and FIG. 6, the center axis 25 is inserted into the center axis hole 27, and the clamping plate 26 is clamped on the No. 1 bolt ball 4. The rod hole 14 is used to insert the ends of the flat rod 7 and the inclined rod 8. By prefabricating the support pad 15 of the No. 1 bolt ball 4 in the concrete sheet 3, the installation of the rod member of the lattice shell 2 avoids the step of drilling holes in the concrete sheet 3.

The main material of the No. 1 bolt ball 4 and the No. 2 bolt ball 6 is a steel body, which has moderate strength and strong corrosion resistance.

Embodiment 2

As another embodiment, this embodiment 2 proposes a more specific steel-concrete composite lattice shell segment based on the embodiment 1, as shown in FIG. 3 and FIG. 4 .

The end of the segment connection block 1 has a double-layer structure, and the connection seam 5 formed by connecting adjacent segment connection blocks 1 is staggered in double layers, which improves the waterproof performance of the segment connection. Steel plates 19 are embedded at both ends of the concrete sheet 3. Adjacent segment connection blocks 1 are connected by arc bolts 17 and straight bolts 21 penetrating the steel plates 19. The steel plates 19 are arranged at the ends of the steel mesh 10 through steel plate anchor bars 20.

Both ends of the arc bolt 17 are provided with threads 23 and nuts 24, which are respectively used to fix the ends of the concrete pieces 3 on both sides of the connection seam 5; while the straight bolt 21 is only provided with threads 23 and nuts 24 at one end, and the straight bolt 21 directly penetrates the steel plates 19 on the ends of the concrete pieces 3 on both sides of the connection seam 5 and is fixed by nuts 24.

The steel sheet 19 is also provided with an arc-shaped bolt hole 9, the lower end of the steel sheet 19 extends out of the concrete sheet 3, and a straight bolt hole 22 is reserved; the straight bolt 21 is fixed through the straight bolt holes 22 on two adjacent steel sheets 19; the arc-shaped bolt hole 9 is provided at the end of the concrete sheet 3 and on the steel sheet 19 corresponding to the inner layer of the double layer of the connecting seam 5, so that the arc-shaped bolt 17 does not penetrate the outer layer of the connecting seam 5, further giving play to the characteristics of the double-layer structure of the connecting seam 5, and the arc-shaped bolt hole 9 does not affect the waterproof effect of the outer layer of the double layer of the connecting seam 5.

It should be noted that the parts in this embodiment that are the same or similar to those in the first embodiment can be referenced to each other and will not be described in detail in this application.

Embodiment 3

As another embodiment, this embodiment 3 is proposed on the basis of the embodiment 2, and the construction method of the steel-concrete composite lattice shell type segment includes the following steps:

Step 1: Tie the steel mesh 10 and set the support of the steel plate 19 and the No. 1 bolt ball 4, install the No. 1 bolt ball 4 through the support, and pour the concrete sheet 3;

Step 2: Assemble the straight rod 7, the oblique rod 8 and the No. 2 bolt ball 6 to form the grid shell 2 in each pipe segment connection block 1, and assemble the grid shell 2 and the concrete sheet 3 through the No. 1 bolt ball 4 to complete the assembly of all pipe segment connection blocks 1;

Step 3: Connect and fix two adjacent segment connecting blocks 1 by arc bolts 17 and straight bolts 21, and connect and fix the grid shells 2 of the two segment connecting blocks 1 by additional rods 18 to make up for the problem of separate construction of grid shells 2 on different concrete sheets 3 in step 2, and lack of connection structure strength of grid shells 2 on both sides of the connection seam 5; form a complete and circumferentially symmetrical segment structure as shown in Figure 1.

Step 4: Lay the internal pipeline of the tunnel in the grid shell 2.

Embodiment 4

As another embodiment, this embodiment 4 proposes, based on the embodiment 3, another construction method of the steel-concrete composite lattice shell type segment, comprising the following steps:

Step 1: Tie the steel mesh 10 and set the support of the steel plate 19 and the No. 1 bolt ball 4, install the No. 1 bolt ball 4 through the support, and pour the concrete sheet 3;

Step 2: First, two adjacent concrete sheets 3 are connected and fixed by arc bolts 17 and straight bolts 21 to form a concrete pipe segment;

Step three, assemble the straight rods 7, the oblique rods 8 and the No. 2 bolt balls 6 to form an annular grid shell 2, and fix the grid shell 2 on the inner side of the concrete ring through the No. 1 bolt balls 4. The grid shell 2 can also be directly assembled on the concrete pipe segment constructed in step two, so that the grid shell 2 on the inner ring of the concrete pipe segment is uniform; this is equivalent to constructing the additional rods 18 in Example 3 as ordinary straight rods 7 simultaneously.

Step 4: Lay the internal pipeline of the tunnel in the grid shell 2.

It should be noted that the parts in this embodiment that are the same or similar to those in Embodiment 3 can be referenced to each other and will not be described in detail in this application.

The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

Claims (7)

1. A steel-concrete composite lattice shell segment, characterized in that it comprises a plurality of segment connection blocks spliced together, each segment connection block comprises a lattice shell and a concrete segment, arc-shaped bolt holes are provided at both ends of the concrete segment, the concrete segment is in an arc shape, and a No. 1 bolt ball is provided on the inner wall of the concrete segment; The No. 1 bolt ball is fixed through the support and the steel mesh of the concrete sheet, the support includes a support pad and a support anchor bar, the No. 1 bolt ball is fixed to the support pad, and the support pad is fixed through the support anchor bar and the steel mesh; The grid shell includes horizontal bars and oblique bars, which are connected by No. 2 bolt balls, and the grid shell is fixed to the inner side of the concrete sheet by No. 1 bolt balls; the internal pipelines of the tunnel are laid within the range of the grid shell; The ends of the segment connection blocks are double-layered, the connection seams formed by adjacent segment connection blocks are staggered in double layers, steel plates are embedded at both ends of the concrete sheet, and the adjacent segment connection blocks are connected by arc bolts and straight bolts penetrating the steel plates. 2. The steel-concrete composite lattice shell segment according to claim 1 is characterized in that arc-shaped bolt holes are also opened on the steel sheet, the lower end of the steel sheet extends out of the concrete sheet, and straight bolt holes are reserved; the straight bolts penetrate the straight bolt holes on two adjacent steel sheets for fixing; the arc-shaped bolt holes are opened in the inner layer of the double layer of the corresponding connection seam between the end of the concrete sheet and the steel sheet. 3. The steel-concrete composite gridshell segment according to claim 1 is characterized in that the gridshell is made of steel, aluminum alloy, carbon fiber or fiberglass, and is a cross truss system, a quadrangular pyramid system, a triangular pyramid system or a curved grid system. When the gridshell is a quadrangular pyramid system, the angle of the diagonal rod in the quadrangular pyramid is 30° to 60°. 4. The steel-concrete composite lattice shell segment according to claim 1 is characterized in that a rod hole and a center axis hole are opened on the No. 1 bolt ball, a center axis and a clamping plate are provided on the support pad, the center axis is inserted into the center axis hole, the clamping plate is clamped on the No. 1 bolt ball, and the rod hole is used to insert the ends of the flat rod and the inclined rod. 5. The steel-concrete composite lattice shell segment according to claim 1 is characterized in that the steel mesh includes transverse steel bars, longitudinal steel bars and stirrups, and the steel plate is arranged on the end of the steel mesh through steel plate anchor bars. 6. The construction method of the steel-concrete composite lattice shell segment according to any one of claims 1 to 5, characterized in that it comprises the following steps: Step 1: Tie the steel mesh and set the support for the steel plate and the No. 1 bolt ball, install the No. 1 bolt ball through the support, and pour the concrete sheet; Step 2: Assemble the straight rods, inclined rods and No. 2 bolt balls to form the grid shell in each segment connection block, and assemble the grid shell and concrete sheet through the No. 1 bolt balls to complete the assembly of all segment connection blocks; Step 3: Connect and fix two adjacent segment connection blocks by using arc bolts and straight bolts, and connect and fix the grid shells of the two segment connection blocks by using additional rods; Step 4: Lay the internal pipelines of the tunnel inside the grid shell. 7. The construction method of the steel-concrete composite gridshell type pipe segment according to claim 6 is characterized in that in step 2 and step 3, two adjacent concrete sheets are first connected and fixed by arc bolts and straight bolts to form a concrete pipe segment, and then the straight rods, inclined rods and No. 2 bolt balls are assembled to form an annular gridshell, and the gridshell is fixed to the inner side of the concrete ring by the No. 1 bolt ball.