CN214787405U - Equal-rigidity lattice and sprayed concrete combined primary support structure - Google Patents

Abstract

The utility model relates to an equal rigidity lattice and shotcrete combination just prop up structure, including just spouting the concrete layer, spouting concrete layer and a plurality of arch steelframe again, the setting of arch steelframe just spouts the concrete layer and spouts the concrete layer again between, links to each other through the tie-beam between the two adjacent roof truss arch steelframes, and the arch steelframe is formed by the concatenation of many lattices, and two adjacent lattices pass through the connecting piece and link to each other, the inside through-hole that is provided with of every lattice, be provided with the pea gravel concrete in the through-hole. Through filling the pea gravel concrete in lattice, two kinds of material advantages complementary of steel lattice and concrete have improved the compressive strength of arch steelframe when having higher moulding and toughness, corrosion resistance and later stage stability. In addition, the arched steel frames are connected into a whole by the connecting beams, so that the longitudinal overall rigidity of the steel frames can be improved, the structure is stressed in a synergistic manner, and the overall stability of the primary support is improved.

Description

Equal-rigidity lattice and sprayed concrete combined primary support structure

Technical Field

The utility model belongs to the technical field of the tunnel is just propped up technique and specifically relates to an equal rigidity lattice and shotcrete combination just prop up structure.

Background

With the further advance of the infrastructure and western development of China, the tunnel and underground engineering are rapidly advanced, and the tunnel engineering construction is developed towards complex geological conditions such as high ground stress, weak and broken zones and the like. In tunnel construction engineering, the primary support type of a tunnel has an important influence on the structural stability of the tunnel, and the primary support of the tunnel generally has modes of wood support, section steel support, grid support, anchor-shotcrete support and the like. The primary support mechanism of the existing tunnel is that when sprayed concrete does not reach enough strength, the steel arch supports the load of surrounding rock, the deformation rate of the surrounding rock is reduced, and along with the setting hardening and strength increase of the sprayed concrete, the pressure of the surrounding rock is converted into the common support of the sprayed concrete, the steel arch, a reinforcing mesh and a bolt composite support system. However, in practice, the synergistic effect between the steel bars (the grid or the section steel) and the concrete is poor, the sprayed concrete is cut into longitudinal rings by the steel arch frame, the steel frame and the sprayed concrete are respectively borne by the steel frame, the adhesion between the steel frame and the sprayed concrete is poor, the gap between the steel frame and the surrounding rock is difficult to be filled and compacted by the sprayed concrete, and cracks appear in the sprayed concrete near the steel frame. Meanwhile, the steel frames are generally connected by longitudinal connecting bars or steel frames and are arranged in a staggered mode, and due to the fact that the strength of the connecting bars is low or the density of the connecting bars is not enough, the overall longitudinal torsion resistance of the steel bars is poor, the steel frames are easy to twist or shear, and finally the supporting capability is lost.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a rigidity lattice and shotcrete combination just prop up structure such as is provided improves the fore-and-aft bulk rigidity of steelframe, makes the structure atress in coordination, and the respective advantage of make full use of solves the steel bow member unstability destruction problem under the loading effect.

The utility model provides a technical scheme that its technical problem adopted is: the equal-rigidity lattice and sprayed concrete combined primary support structure comprises a primary sprayed concrete layer, a secondary sprayed concrete layer and a plurality of arched steel frames, wherein the arched steel frames are arranged between the primary sprayed concrete layer and the secondary sprayed concrete layer, two adjacent arched steel frames are connected through connecting beams,

the arched steel frame is formed by splicing a plurality of lattices, two adjacent lattices are connected through a connecting piece, a through hole is arranged in each lattice, and fine aggregate concrete is arranged in the through hole.

Furthermore, the lattice comprises I-shaped steel, steel plates are welded on two sides of the I-shaped steel, and the steel plates and the I-shaped steel enclose two through holes.

Furthermore, the connecting piece is a connecting sleeve, and two ends of the connecting sleeve are sleeved at the end parts of two adjacent lattices and connected with the lattices through first bolts.

Further, the connecting sleeve comprises two sleeves, and the two sleeves are welded on two side faces of the partition plate.

Further, the connecting beam is a steel rib plate.

Furthermore, the two ends of the steel rib plate are connected with connecting plates perpendicular to the steel rib plate, and the connecting plates are attached to the side faces of the lattice and connected with the lattice through second bolts.

Further, the connecting plate is connected with the steel rib plate in a welding mode.

Further, the second bolt comprises a stud, one end of the stud is in threaded connection with the lattice, and the other end of the stud penetrates through the connecting plate and then is in threaded connection with the nut.

Further, grooves or holes are reserved on the outer wall of the lattice.

Further, a plurality of foot locking anchor rods are arranged at the connecting piece.

The utility model has the advantages that: through filling the pea gravel concrete in lattice, two kinds of material advantages complementary of steel lattice and concrete have improved the compressive strength of arch steelframe when having higher moulding and toughness, corrosion resistance and later stage stability. In addition, the arched steel frames are connected into a whole by the connecting beams, so that the longitudinal overall rigidity of the steel frames can be improved, the structure is stressed in a synergistic manner, and the overall stability of the primary support is improved.

Drawings

FIG. 1 is a schematic overall cross-sectional view of the present invention;

FIG. 2 is a schematic top view of the arched steel frames of the present invention connected by connecting beams;

FIG. 3 is a schematic cross-sectional view A-A of FIG. 2;

FIG. 4 is a schematic view of the lattice in connection with a connecting beam;

FIG. 5 is a schematic view of a connection between two adjacent lattices;

FIG. 6 is a schematic cross-sectional view of B-B of FIG. 5;

reference numerals: 1-lattice; 11-i-section steel; 12-a steel plate; 2, connecting pieces; 21-a sleeve; 22-a separator; 3-a second bolt; 4-fine stone concrete; 5, connecting the beams; 51-a connecting plate; 6-first bolt; 7-primary spraying of a concrete layer; 8-spraying a concrete layer again; 9-locking the anchor rod.

Detailed Description

The present invention will be further explained with reference to the drawings and examples.

As shown in fig. 1 and 2, the utility model discloses an equal rigidity lattice and shotcrete combination just prop up structure, including just spouting concrete layer 7, respraying concrete layer 8 and a plurality of arch steelframe, the setting of arch steelframe is just spouting between concrete layer 7 and respraying concrete layer 8, links to each other through tie-beam 5 between the two adjacent arch steelframes. The arch steelframe is formed by the concatenation of many check 1, and two adjacent check 1 link to each other through connecting piece 2, and every 1 inside through-holes that are provided with of check, be provided with pea gravel concrete 4 in the through-hole.

The hoop setting in tunnel is followed to the arch steelframe, and for the convenience of construction, divide into multistage lattice 1 with the arch steelframe, and two adjacent lattice 1 link to each other through connecting piece 2, and connecting piece 2 can be current various steel connecting pieces, like steel connection plate etc. preferably, as shown in fig. 5 and fig. 6, connecting piece 2 is the adapter sleeve, the both ends cover of adapter sleeve just links to each other with lattice 1 through first bolt 6 at the tip of two adjacent lattices 1. During construction, one end of the connecting sleeve is firstly sleeved at the end part of the lattice 1 which is already constructed, the end part of the next lattice 1 to be constructed is inserted into the other end of the connecting sleeve, and then the first bolt 6 is screwed down, so that the operation is convenient, and the efficiency can be improved.

For the stability of the connection sleeve, the connection sleeve comprises two sleeves 21 of the same length, the two sleeves 21 being welded on both sides of the partition 22. Two sleeves 21 overlap respectively at the tip of two adjacent lattice 1, and baffle 22 and lattice 1's tip contact separate lattice 1 through baffle 22, play the effect of hoop location, can guarantee that two sleeves 21 overlap the length unanimous on lattice 1 to improve the stability of connecting. In addition, the bending resistance bearing capacity at the node can be improved.

Lattice 1 sets up to hollow structure, and during the construction at its inside fine aggregate concrete 4 that fills, can realize that the lattice 1 of steel material is complementary with two kinds of material advantages of concrete, has improved the compressive strength, the corrosion resistance of arch steelframe and the stability in later stage when higher moulding and toughness.

The lattice 1 can adopt rectangular steel and the like, preferably, as shown in fig. 3, the lattice 1 comprises an I-shaped steel 11, steel plates 12 are welded on two sides of the I-shaped steel 11, and the steel plates 12 and the I-shaped steel 11 enclose two through holes, so that the lattice 1 is in a reversed Chinese character shape, the rigidity of the lattice 1 is increased, and the instability is less prone to being caused compared with a common steel frame.

Two adjacent arched steel frames are connected into a whole through a connecting beam 5, so that the overall rigidity and stability of primary support are further ensured, the connecting beam 5 can be various profiles, preferably, as shown in fig. 3 and 4, the connecting beam 5 is a steel rib plate, two ends of the steel rib plate are connected with connecting plates 51 perpendicular to the steel rib plate, and the connecting plates 51 are attached to the side surfaces of the lattice 1 and connected with the lattice 1 through second bolts 3. The steel rib plates and the connecting plates 51 at the two ends form an I shape, so that the construction difficulty is not increased while the connection strength is ensured.

The connecting plate 51 is connected with the steel rib plate in a welding mode, and the connecting strength is high.

In order to facilitate the installation of the second bolt 3, the second bolt 3 comprises a stud, one end of the stud is in threaded connection with the lattice 1, and the other end of the stud penetrates through the connecting plate 51 and then is in threaded connection with a nut. During construction, one end of the stud is screwed into the threaded hole in the side wall of the lattice 1, the other end of the stud penetrates through the through hole in the connecting plate 51, and finally the nut is installed to keep the connecting plate 51 stable.

Grooves or holes are reserved on the outer wall of the lattice 1 so as to increase the friction force between the primary sprayed concrete layer 7 and the secondary sprayed concrete layer 8 and the lattice 1, and the stability is improved.

The position that sets up connecting piece 2 is the weak point of arch steelframe, consequently, connecting piece 2 department is provided with many lock foot stock 9, and stability obtains improving.

During construction, a primary sprayed concrete layer 7 is firstly constructed, then arch steel frames are constructed one by one, and finally a secondary sprayed concrete layer 8 is constructed. When the arched steel frame is constructed, a section of lattice 1 is installed in place, then the fine aggregate concrete 4 is injected into the lattice 1, the connecting piece 2 can be installed when the strength of the fine aggregate concrete reaches 30%, the first bolt 6 is screwed down, and then the next section of lattice 1 is installed. After finishing two arched steel frames, the two arched steel frames can be connected by using a plurality of connecting beams 5, and then the next arched steel frame is constructed.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. Equal rigidity lattice and shotcrete combination just prop up structure, including just spouting concrete layer (7), compound concrete layer (8) and a plurality of arch steelframe, the setting of arch steelframe is just spouting between concrete layer (7) and compound concrete layer (8), links to each other its characterized in that through tie-beam (5) between the two adjacent arch steelframes:

the arched steel frame is formed by splicing a plurality of lattices (1), two adjacent lattices (1) are connected through a connecting piece (2), a through hole is formed in each lattice (1), and fine aggregate concrete (4) is arranged in the through hole.

2. The equal stiffness lattice and shotcrete combined primary support structure of claim 1, wherein: the lattice (1) comprises I-shaped steel (11), steel plates (12) are welded on two sides of the I-shaped steel (11), and the steel plates (12) and the I-shaped steel (11) enclose two through holes.

3. The equal stiffness lattice and shotcrete combined primary support structure of claim 1, wherein: the connecting piece (2) is a connecting sleeve, and two ends of the connecting sleeve are sleeved at the end parts of the two adjacent lattices (1) and connected with the lattices (1) through first bolts (6).

4. The equal stiffness lattice and shotcrete combined primary support structure of claim 3, wherein: the connecting sleeve comprises two sleeves (21), and the two sleeves (21) are welded on two side faces of the partition plate (22).

5. The equal stiffness lattice and shotcrete combined primary support structure of claim 1, wherein: the connecting beam (5) is a steel rib plate.

6. The equal stiffness lattice and shotcrete combined primary support structure of claim 5, wherein: the two ends of the steel rib plate are connected with connecting plates (51) perpendicular to the steel rib plate, and the connecting plates (51) are attached to the side faces of the lattice structure (1) and connected with the lattice structure (1) through second bolts (3).

7. The equal stiffness lattice and shotcrete combined primary support structure of claim 6, wherein: and the connecting plate (51) is connected with the steel rib plate in a welding manner.

8. The equal stiffness lattice and shotcrete combined primary support structure of claim 6, wherein: the second bolt (3) comprises a stud, one end of the stud is in threaded connection with the lattice (1), and the other end of the stud penetrates through the connecting plate (51) and then is in threaded connection with the nut.

9. The equal stiffness lattice and shotcrete combined primary support structure of claim 1, wherein: grooves or holes are reserved in the outer wall of the lattice (1).

10. The equal stiffness lattice and shotcrete combined primary support structure of claim 1, wherein: and a plurality of foot locking anchor rods (9) are arranged at the connecting piece (2).

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