Close-splicing laminated slab connecting structure of fiber grid reinforced prefabricated bottom slab and construction method of close-splicing laminated slab connecting structure

Abstract

The invention relates to a closely-spliced laminated slab connecting structure of a fiber grid reinforced prefabricated bottom slab, which comprises a concrete prefabricated bottom slab, a bidirectional fiber fabric grid reinforced layer and an oblique bending steel bar, and is characterized in that the bidirectional fiber fabric grid reinforced layer is embedded in the bottom of the prefabricated bottom slab; every two adjacent prefabricated bottom plates in the left-right direction are tightly spliced and clamped through trapezoid protrusions and trapezoid concave holes in the two sides of the plates, plate bottom longitudinal load-bearing steel bars in the plates obliquely and upwards stretch out at the positions close to the ends of the plates to form obliquely-bent steel bars, and post-pouring concrete layers provided with plate face two-way steel bars are arranged on the upper portions of the prefabricated bottom plates. And the extending parts of the inclined bent steel bars are anchored into the post-pouring concrete layer. The bidirectional fiber fabric grid reinforcing layer is embedded in the bottom of the prefabricated bottom plate, so that the flexural capacity of the prefabricated bottom plate and the anti-cracking strength of plate bottom concrete are improved, and plate bottom supports can be properly reduced; the stress at the bottom of the plate is transmitted by obliquely bending the steel bars, so that the bearing capacity of the closely-spliced laminated plate is enhanced; and the structural integrity is better, and the bearing capacity is higher.

Description

Technical Field

[0001] The invention relates to the field of prefabricated building construction, and in particular to a close-jointed composite plate connection structure of a fiber grid reinforced prefabricated base plate and a construction method thereof. Background Art

[0002] Compared with traditional construction methods, prefabricated buildings have the advantages of saving natural resources, reducing environmental pollution, shortening construction time, and improving building quality. At present, prefabricated buildings are developing rapidly across the country, especially in concrete structures. Concrete composite slabs are widely used in engineering practice by combining prefabricated base plates with post-cast concrete layers.

[0003] Common concrete composite slabs in engineering usually adopt the 6+7 model, that is, a 70mm thick cast-in-place layer is poured on top of a 60mm thick prefabricated bottom plate, with a thickness of 130mm. Usually, the integral joints between the prefabricated bottom plates of the two-way slabs require a 200-300mm cast-in-place strip to be reserved, and temporary supports need to be set up during on-site construction. In traditional structural construction, a full-frame support is set up at the bottom, and accessories such as sweeping rods, two-way horizontal rods, scissor braces, and adjustable top supports are set up. At the same time, the temporary support needs to be dismantled in the later stage, which requires a lot of manpower, material resources and construction time.

[0004] To this end, in recent years, many scholars and experts have proposed a close connection method without reinforcement on the edge of the plate. However, during on-site construction, the two adjacent prefabricated bottom plates need to be repeatedly aligned and leveled, and the connection at the joints is not tight enough. The existence of joints reduces the rigidity of the composite plate, and the deformation is concentrated at the joints, making it difficult for the composite plate to achieve the effect of "equivalent to cast-in-place". Summary of the invention

[0005] In order to solve the technical problems existing in the prior art, the present invention provides a close-jointed composite plate connection structure of a fiber grid reinforced prefabricated base plate and a construction method thereof.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] A close-jointed composite plate connection structure of a fiber grid reinforced prefabricated base plate comprises a concrete prefabricated base plate, a bidirectional fiber fabric grid reinforcement layer and obliquely bent steel bars. The bidirectional fiber fabric grid reinforcement layer is embedded in the bottom of the concrete prefabricated base plate. Mutually matching trapezoidal protrusions and trapezoidal recesses are respectively provided on both sides of the concrete prefabricated base plate. Two adjacent concrete prefabricated base plates on the left and right are closely joined together through the trapezoidal protrusions and trapezoidal recesses. The obliquely bent steel bars are formed by the longitudinal force-bearing steel bars at the bottom of the concrete prefabricated base plate extending obliquely upward from the concrete prefabricated base plate near the plate end. A post-cast concrete layer with bidirectional steel bars on the plate surface is provided on the upper part of the concrete prefabricated base plate, and the protruding part of the obliquely bent steel bars is anchored in the post-cast concrete layer.

[0008] As a preferred technical solution, the bidirectional fiber fabric grid reinforcement layer is laid 10 mm above the bottom of the precast concrete slab, with 1-3 layers laid.

[0009] As a preferred technical solution, the fiber composite of the bidirectional fiber fabric grid reinforcement layer is one or more of glass fiber composite, carbon fiber composite, basalt fiber composite and aramid fiber composite.

[0010] As a preferred technical solution, the trapezoidal protrusion is arranged at the side joint of the concrete precast base plate, 20 mm away from the bottom of the plate, the hypotenuse of the trapezoidal protrusion is 120° with the plate joint, the hypotenuse height of the trapezoidal protrusion is 5 mm, the bottom height is 10 mm, and the length of the protruding part is 10 mm.

[0011] As a preferred technical solution, reinforcing ribs are provided inside the precast concrete bottom plate and inside the trapezoidal protruding portion. The reinforcing ribs are located 25 mm from the bottom of the plate, and the tail ends of the reinforcing ribs are located 5 mm from the trapezoidal protruding portion.

[0012] As a preferred technical solution, the length of the reinforcing bar is 100 mm, and it is fixed to the oblique bent steel bars by steel wire binding, and the lap length of the reinforcing bar and the oblique bent steel bars is 50 mm.

[0013] As a preferred technical solution, the bending angle of the obliquely bent steel bar is between 30° and 60°, and the bending point of the obliquely bent steel bar is 40mm-50mm away from the plate seam.

[0014] As a preferred technical solution, the oblique bent steel bars in the two adjacent left and right precast concrete slabs are cross-arranged and the upper protruding parts are spaced 5 mm apart.

[0015] As a preferred technical solution, a method for constructing a close-jointed composite plate connection structure of a fiber grid reinforced prefabricated base plate comprises the following steps:

[0016] Step S1: prefabricate a prefabricated concrete base plate;

[0017] Step S2: Arrange precast concrete floor support;

[0018] Step S3: hoisting and closely assembling the prefabricated concrete base plate;

[0019] Step S4: arranging bidirectional stress-bearing steel bars on the top of the slab above the truss steel bars;

[0020] Step S5: pouring the concrete superposition layer.

[0021] As a preferred technical solution, step one includes: setting trapezoidal protrusions and trapezoidal recesses on the mold in advance, and arranging a bidirectional fiber fabric grid 10 mm away from the bottom of the board; arranging bidirectional force-bearing longitudinal reinforcements on the bottom of the board 20 mm away from the bottom of the board, and the longitudinal reinforcements are bent obliquely upward on the side of the board, and the bending angle is between 30°-60°, and the bending point is 40mm-50mm away from the side of the board; the reinforcing bars in the trapezoidal protrusion are tied and overlapped with the obliquely bent steel bars, the tying overlap length is 50mm, and the tail end of the reinforcing bar is located 5mm away from the trapezoidal protrusion; truss steel bars are laid on the upper part of the longitudinal steel bars; and concrete is poured to complete the production of the concrete precast base plate.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The fiber grid reinforced prefabricated base plate close-joined composite plate connection structure and construction method of the present invention have a bidirectional fiber fabric grid reinforcement layer embedded in the bottom of the concrete prefabricated base plate, which can effectively improve the bending bearing capacity of the prefabricated base plate and the crack resistance of the base plate concrete, thereby appropriately reducing the base plate support; the trapezoidal protrusions and recessed hole engagement parts can achieve rapid close joining between the prefabricated base plates, and the construction is convenient and accurate; the obliquely bent steel bars can effectively transfer the base plate stress and enhance the bearing capacity of the close-joined composite plates; when the thickness of the prefabricated base plate remains unchanged, the position of the base plate longitudinal reinforcement arranged inside it is moved up 10-15mm relative to the ordinary base plate, and the thickness of the post-cast concrete layer can be increased by about 10mm, the structural integrity is better, the bearing capacity is stronger, and the base plate support operation can be reduced during construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the close-joined laminated plate connection structure of the fiber grid reinforced prefabricated base plate of the present invention;

[0025] Figure 2 It is a front cross-sectional view of a concrete prefabricated base plate in a close-joined composite plate connection structure of a fiber grid reinforced prefabricated base plate of the present invention;

[0026] Figure 3 It is a top view of obliquely bent steel bars in a concrete prefabricated bottom plate in a close-jointed composite plate connection structure of a fiber grid reinforced prefabricated bottom plate of the present invention;

[0027] Figure 4 It is a top view of the connection structure of the obliquely bent steel bars and the reinforcing bars in the close-jointed composite plate connection structure of the fiber grid reinforced prefabricated base plate of the present invention;

[0028] Figure 5 yes Figure 2 Enlarged view of part A.

[0029] In the figure: 1. Precast concrete base plate; 2. Bidirectional fiber fabric grid reinforcement layer; 3. Joints; 4. Trapezoidal protrusions; 5. Trapezoidal recesses; 6. Reinforcement bars; 7. Obliquely bent steel bars; 8. Post-cast concrete layer; 9. Truss steel bars; 10. Bidirectional force-bearing steel bars on the top of the plate; 11. Bending of the obliquely bent steel bars. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is further described below in conjunction with specific implementation methods:

[0031] like Figure 1 As shown, a close-jointed composite plate connection structure of a fiber mesh reinforced prefabricated base plate comprises a concrete prefabricated base plate 1, a bidirectional fiber fabric mesh reinforcement layer 2, and obliquely bent steel bars 7. The bidirectional fiber fabric mesh reinforcement layer 2 is embedded in the bottom of the concrete prefabricated base plate 1. The two sides of the concrete prefabricated base plate 1 are respectively provided with mutually matching trapezoidal protrusions 4 and trapezoidal recesses 5. The two adjacent concrete prefabricated base plates 1 on the left and right are closely joined together through the trapezoidal protrusions 4 and the trapezoidal recesses 5. The obliquely bent steel bars 7 are formed by the longitudinal force-bearing steel bars at the bottom of the concrete prefabricated base plate 1 in the concrete prefabricated base plate 1 extending obliquely upward from the concrete prefabricated base plate 1 near the plate end. A post-cast concrete layer 8 with bidirectional steel bars on the plate surface is provided on the upper part of the concrete prefabricated base plate 1. The protruding part of the obliquely bent steel bars 7 is anchored in the post-cast concrete layer 8.

[0032] The bidirectional fiber fabric grid reinforcement layer 2 is laid 10 mm above the bottom of the precast concrete base plate 1, and 1 to 3 layers are laid.

[0033] The fiber composite material of the bidirectional fiber fabric grid reinforcement layer 2 is one or more of glass fiber composite material, carbon fiber composite material, basalt fiber composite material and aramid fiber composite material.

[0034] like Figure 5 As shown, the trapezoidal protrusion 4 is arranged at the side joint 3 of the concrete precast base plate 1, located 20 mm away from the bottom of the plate, the hypotenuse of the trapezoidal protrusion 4 is 120° with the plate joint, the hypotenuse height of the trapezoidal protrusion 4 is 5 mm, the bottom height is 10 mm, and the length of the protruding part is 10 mm.

[0035] Reinforcement ribs 6 are arranged inside the concrete precast bottom plate 1 and inside the trapezoidal protrusion 4. The reinforcement ribs 6 are located 25 mm from the bottom of the plate, and the tail end of the reinforcement ribs 6 is located 5 mm from the trapezoidal protrusion 4.

[0036] like Figure 4 As shown, the length of the reinforcing bar 6 is 100 mm, and it is fixed to the oblique bent steel bar 7 by steel wire binding, and the lap length of the reinforcing bar 6 and the oblique bent steel bar 7 is 50 mm.

[0037] like Figure 2As shown, the bending angle of the obliquely bent steel bar 7 is between 30° and 60°, and the bending point 11 of the obliquely bent steel bar 7 is 40mm-50mm away from the plate seam.

[0038] like Figure 3 As shown, the obliquely bent steel bars 7 in the two adjacent left and right precast concrete bottom plates 1 are cross-arranged and the upper protruding parts are spaced 5 mm apart.

[0039] A method for constructing a close-jointed composite plate connection structure of a fiber grid reinforced prefabricated base plate comprises the following steps:

[0040] Step S1: prefabricate a prefabricated concrete base plate 1;

[0041] Specifically, the mold is provided with a trapezoidal protrusion 4 and a trapezoidal recess 5 in advance; a bidirectional fiber fabric grid is arranged 10 mm away from the bottom of the plate; bidirectional force-bearing longitudinal reinforcements are arranged 20 mm away from the bottom of the plate, and the longitudinal reinforcements are bent obliquely upward on the side of the plate, with a bending angle of 30°-60°, and the bending point 11 is 40 mm-50 mm away from the side of the plate; the reinforcing ribs 6 in the trapezoidal protrusion 4 are tied and overlapped with the obliquely bent steel bars 7, with a tying overlap length of 50 mm, and the tail end of the reinforcing ribs 6 is located 45 mm away from the trapezoidal protrusion; truss steel bars 9 are laid on the upper part of the longitudinal steel bars; concrete is poured to complete the production of the precast concrete base plate 1.

[0042] Step S2: Arrange the prefabricated concrete base plate 1 support;

[0043] Specifically, the supports are reasonably arranged according to the size and span of the precast concrete base plate 1. Compared with the traditional structure construction in which a full-frame support is set up at the bottom, the present invention can appropriately reduce the arrangement of the base plate support.

[0044] Step S3: hoisting and closely assembling the prefabricated concrete base plate 1;

[0045] Specifically, according to the size and layout requirements of the panel, multiple prefabricated concrete bottom plates 1 are placed on the beam edge and the support for close assembly, and the trapezoidal protrusions 4 on the plate sides of the adjacent prefabricated concrete bottom plates 1 on the left and right are closely assembled and engaged with the trapezoidal recesses 5, and the multiple prefabricated concrete bottom plates 1 are placed in a horizontal state;

[0046] Step S4: arranging the bidirectional stress-bearing steel bars 10 on the top of the truss steel bars 9;

[0047] Specifically, the bidirectional force-bearing steel bars 10 on the top of the slab and the truss steel bars 9 are tied together with steel wires to form a spatial truss force transmission system.

[0048] Step S5: pouring the concrete superposition layer.

[0049] Specifically, after the bidirectional reinforcement binding of the post-cast concrete layer 8 is completed, the post-cast concrete layer 8 is poured and vibrated to be dense, and after the vibration is completed, standard concrete curing is carried out.

[0050] This embodiment is only a further explanation of the invention rather than a limitation of the invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as they are within the scope of the claims of the invention, they are protected by the patent law.

Claims

1. A fiber grid reinforced prefabricated base plate close-joined plate connection structure, characterized in that: It includes a precast concrete base plate, a bidirectional fiber fabric grid reinforcement layer, and obliquely bent steel bars. The bidirectional fiber fabric grid reinforcement layer is embedded in the bottom of the precast concrete base plate. The two sides of the precast concrete base plate are respectively provided with mutually matching trapezoidal protrusions and trapezoidal recesses. The two adjacent precast concrete base plates on the left and right are tightly spliced ​​and engaged through the trapezoidal protrusions and trapezoidal recesses. The obliquely bent steel bars are formed by the longitudinal force-bearing steel bars at the bottom of the precast concrete base plate in the precast concrete base plate extending obliquely upward from the precast concrete base plate near the plate end. A post-cast concrete layer with bidirectional steel bars on the plate surface is provided on the upper part of the precast concrete base plate, and the protruding part of the obliquely bent steel bars is anchored in the post-cast concrete layer.

2. The close-jointed composite board connection structure of the fiber grid reinforced prefabricated base plate according to claim 1 is characterized in that: The bidirectional fiber fabric grid reinforcement layer is laid 10 mm above the bottom of the concrete prefabricated bottom plate, and is laid in 1-3 layers.

3. The close-jointed composite board connection structure of the fiber grid reinforced prefabricated base plate according to claim 1 is characterized in that: The fiber composite material of the bidirectional fiber fabric grid reinforcement layer is one or more of glass fiber composite material, carbon fiber composite material, basalt fiber composite material and aramid fiber composite material.

4. The close-jointed composite board connection structure of the fiber grid reinforced prefabricated base plate according to claim 1 is characterized in that: The trapezoidal protrusion is arranged at the side joint of the concrete precast base plate, located 20 mm away from the bottom of the plate, the hypotenuse of the trapezoidal protrusion is 120° with the plate joint, the hypotenuse height of the trapezoidal protrusion is 5 mm, the bottom height is 10 mm, and the length of the protruding part is 10 mm.

5. The close-jointed composite board connection structure of the fiber grid reinforced prefabricated base plate according to claim 1 is characterized in that: Reinforcement ribs are arranged inside the concrete precast bottom plate and inside the trapezoidal protruding part. The reinforcement ribs are located 25 mm from the bottom of the plate, and the tail ends of the reinforcement ribs are located 5 mm from the trapezoidal protruding part.

6. The close-jointed composite board connection structure of the fiber grid reinforced prefabricated base plate according to claim 5 is characterized in that: The length of the reinforcing bar is 100 mm, and it is fixed to the oblique bent steel bar by steel wire binding. The lap length of the reinforcing bar and the oblique bent steel bar binding is 50 mm.

7. The close-jointed composite board connection structure of the fiber grid reinforced prefabricated base plate according to claim 1 is characterized in that: The bending angle of the obliquely bent steel bar is between 30° and 60°, and the bending point of the obliquely bent steel bar is 40mm-50mm away from the plate seam.

8. The close-jointed composite board connection structure of the fiber grid reinforced prefabricated base plate according to claim 1 is characterized in that: The oblique bent steel bars in the two adjacent left and right precast concrete slabs are arranged crosswise and the upper protruding parts are spaced 5 mm apart.

9. A method for constructing a close-jointed composite plate connection structure of a fiber grid reinforced prefabricated base plate according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: Step S1: prefabricate a prefabricated concrete base plate; Step S2: Arrange precast concrete floor support; Step S3: hoisting and closely assembling the prefabricated concrete base plate; Step S4: arranging bidirectional stress-bearing steel bars on the top of the slab above the truss steel bars; Step S5: pouring the concrete superposition layer.

10. The method for constructing the close-jointed composite plate connection structure of the fiber grid reinforced prefabricated base plate according to claim 9, characterized in that: The step 1 comprises: setting trapezoidal protrusions and trapezoidal concave holes on the mold in advance, arranging a bidirectional fiber fabric grid at a distance of 10 mm from the bottom of the board; arranging bidirectional longitudinal reinforcements at a distance of 20 mm from the bottom of the board, the longitudinal reinforcements are bent upward obliquely at the side of the board, the bending angle is between 30° and 60°, and the bending point is 40 mm to 50 mm away from the side of the board; The reinforcement bars in the exit part are tied and overlapped with the obliquely bent steel bars, and the lap length is 50mm. The tail end of the reinforcement bar is located at 5mm of the trapezoidal protrusion; truss reinforcement is laid on the upper part of the longitudinal reinforcement; Pouring concrete completes the production of the precast concrete base slab.

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