A close-jointed precast concrete bidirectional composite floor slab with ribbed beams and construction method

Abstract

The present invention discloses a precast concrete bidirectional composite slab with ribbed beams and a construction method. The upper surface of the composite slab is provided with a plurality of transverse and mutually parallel reinforced concrete ribs, and the ribs are integrally formed with the composite slab. A steel mesh is provided in the plate body of the composite slab, and the steel mesh is formed by binding a plurality of transverse steel bars and a plurality of longitudinal steel bars, and the two ends of the transverse steel bars are exposed from the side of the composite slab, while the two ends of the longitudinal steel bars are not exposed from the side of the composite slab. At least one of the two longitudinal sides on the upper surface of the composite slab is provided with a plurality of longitudinally parallel grooves, and the groove passes through the middle and lower part of at least one rib beam, and the portion of the groove directly below the rib beam is provided with a through hole.

Description

Technical Field

[0001] The invention relates to the technical field of precast concrete composite floor slabs, in particular to a close-jointed precast concrete bidirectional composite floor slab. Background Art

[0002] At present, with the vigorous development of the construction industry, traditional housing construction technology can no longer meet the housing needs of modern society due to a series of problems such as low production efficiency, slow construction speed, high pollution and long construction period.

[0003] Prefabricated buildings refer to buildings that transfer a large amount of on-site work in traditional construction methods to factories, where building components and accessories (such as floor slabs, wall panels, stairs, balconies, etc.) are processed and manufactured in the factory, transported to the construction site, and assembled and installed on site through reliable connection methods.

[0004] Prefabricated buildings mainly include prefabricated and assembled concrete structures. Because they adopt standardized design, factory production, assembly construction, information management, and intelligent applications, they are representatives of modern industrialized production methods.

[0005] Composite floor slab is an assembled integral floor slab composed of prefabricated composite floor slab and cast-in-place reinforced concrete. Prefabricated composite floor slab is prefabricated in the factory, transported to the site and hoisted into place by tower crane. Equipment pre-buried pipelines are laid on the prefabricated composite floor slab, and then the upper steel mesh of the composite floor slab is laid. Finally, the cast-in-place concrete on the prefabricated composite floor slab is poured. The prefabricated composite floor slab is both a component of the structural floor slab and a permanent formwork for the cast-in-place reinforced concrete on it.

[0006] Precast composite slabs are specifically divided into one-way composite slabs (rebars are exposed on only two sides) and two-way composite slabs (rebars are exposed on all four sides). According to the description in 6.6.3 of the Technical Code for Prefabricated Concrete Structures (JGJ1-2014), "When separate joints are used between precast slabs, they should be designed as one-way slabs. For four-side supported composite slabs with an aspect ratio of no more than 3, when integral joints or no joints are used between the precast slabs, they can be designed as two-way slabs." Accordingly, when the slab is large and needs to be divided and designed, separate joints are used for one-way slab design; when two-way slab design is used, integral joints are used for slabs with an aspect ratio of no more than 3.

[0007] One-way composite slabs have reinforcement only on two sides, which makes construction and installation easy and efficient, but the joints are obvious and cracks are likely to occur if they are not properly repaired at a later stage.

[0008] The connection between two-way composite slabs is usually in the form of post-cast strips, also known as integral joints (joint width 200-500mm), which have complex structure and cumbersome construction, and steel bars often collide; separate formwork and scaffolding are required at the post-cast strips, and it is impossible to achieve complete formwork and support-free (assuming a living room has 3 composite slabs and 2 joints of about 500mm width. The installation of the composite slabs requires 18 vertical supports and 9 discontinuous square timbers, and the formwork requires 2 templates and 6 supports. The construction is very difficult and the quality is difficult to guarantee); the top supporting beams are forced to be cut off, and it is impossible to ensure that the tops of both sides are flush. Measurement and leveling require a lot of manpower, which reduces work efficiency and seriously restricts the application of two-way composite slabs.

[0009] Therefore, developing a dense precast concrete composite floor slab that does not require a supporting formwork has become one of the technical problems that urgently need to be solved in this field. Summary of the invention

[0010] The purpose of the present invention is to provide a close-jointed precast concrete bidirectional composite floor slab with ribbed beams and a construction method.

[0011] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0012] A close-jointed precast concrete bidirectional composite floor with ribbed beams, wherein the upper surface of the composite floor is provided with a plurality of transverse, mutually parallel ribbed beams made of reinforced concrete, and the ribbed beams and the composite floor are integrally formed;

[0013] A steel mesh is provided in the plate body of the composite floor slab, and the steel mesh is formed by binding a plurality of transverse steel bars and a plurality of longitudinal steel bars, the two ends of the transverse steel bars are exposed from the side of the composite floor slab, and the two ends of the longitudinal steel bars are not exposed from the side of the composite floor slab;

[0014] At least one of the two longitudinal sides of the upper surface of the composite floor is provided with a plurality of longitudinally parallel grooves, the grooves pass through the middle and lower part of at least one rib beam, and the portion of the groove directly below the rib beam is provided with a through hole.

[0015] The rib beam is provided with an upper and lower layer of transverse steel bars, each layer of transverse steel bars has two steel bars, and the upper and lower layers of transverse steel bars are tied together by a number of mutually parallel stirrups. The cross section of the rib beam is trapezoidal.

[0016] Wherein, the upper surface of the rib beam is provided with a plurality of evenly distributed rib beam grooves.

[0017] Wherein, a plurality of longitudinal through holes are provided in the middle and lower part of the rib beam located in the middle part of the upper surface of the composite floor slab.

[0018] The number of through holes in the rib beams at the middle of the upper surface of the composite floor slab is less than the number of through holes in the rib beams at the edge of the upper surface of the composite floor slab.

[0019] Wherein, the upper surface of the composite floor is a rough surface.

[0020] When the composite floor is a side plate, only one of the two longitudinal sides of the upper surface of the composite floor is provided with a plurality of longitudinally parallel grooves.

[0021] When the composite floor is a middle plate, a plurality of longitudinally parallel grooves are provided on both longitudinal sides of the upper surface of the composite floor.

[0022] The construction method of the close-joined precast concrete bidirectional composite floor slab with ribbed beams of the present invention is specifically as follows: two adjacent close-joined precast concrete bidirectional composite floor slabs are closely joined and arranged, the overlapping steel bars are passed through the through holes in the rib beams at the edge of the slab body, and are placed in the grooves of the two adjacent close-joined precast concrete bidirectional composite floor slabs, and the embedded electric wires are passed through the through holes in the rib beams in the middle of the slab body and the through holes in the rib beams at the edge of the slab body. After the arrangement is completed, the upper steel mesh is laid, and concrete is poured to form a cast-in-place layer of the composite floor slab.

[0023] Compared with the prior art, the outstanding effects of the present invention are:

[0024] (1) The close-joined precast concrete bidirectional composite floor slab with ribbed beams of the present invention can be constructed in a close-joined manner without the need for formwork, which can save 2 / 3 of the construction materials and 80% of the labor costs.

[0025] (2) Overlap steel bars (straight bars) are installed in the grooves of two adjacent closely-assembled precast concrete bidirectional composite slabs to ensure real overlap and force transmission, thus meeting the seismic resistance requirements of the building.

[0026] (3) The close-jointed precast concrete two-way composite floor with ribbed beams of the present invention is provided with a plurality of ribbed beams, and the structural strength is much higher than that of the conventional triangular steel truss. Moreover, the overlapping steel bars of two adjacent close-jointed precast concrete two-way composite floor slabs pass through the ribbed beams on the two slabs to form a mesh structure. The force is transmitted through the overlapping of the steel bars, thereby ensuring the connection strength at the joints.

[0027] (4) The upper surface of the close-jointed precast concrete bidirectional composite floor with ribbed beams of the present invention is a rough surface, and a large number of rib grooves are formed on the upper surface of the ribbed beams, which ensures the bonding strength between the composite floor and the upper cast-in-place layer, greatly avoids the separation or misalignment of the upper and lower layers, and has better earthquake resistance.

[0028] The close-joined precast concrete bidirectional composite floor slab with ribbed beams and the construction method of the present invention are further described below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a top cross-sectional view of a close-assembled precast concrete bidirectional composite floor slab (middle slab) with ribbed beams according to the present invention;

[0030] Figure 2 It is a front cross-sectional view of a close-assembled precast concrete bidirectional composite floor slab (middle slab) with ribbed beams according to the present invention;

[0031] Figure 3 It is a left sectional view of the close-jointed precast concrete bidirectional composite floor slab (middle slab) with ribbed beams of the present invention;

[0032] Figure 4 for Figure 1 A partial enlarged view of the area “A”;

[0033] Figure 5 for Figure 1 A partial enlarged view of the area "B" in the middle;

[0034] Figure 6 for Figure 2 A partial enlarged view of the "C" in the middle;

[0035] Figure 7 for Figure 3 A partial enlarged view of the "D" in the middle;

[0036] Figure 8 It is a top cross-sectional view of a close-assembled precast concrete bidirectional composite floor slab (side slab) with ribbed beams of the present invention;

[0037] Fig. 9 It is a partial stereoscopic view of the close-assembled precast concrete two-way composite floor slab with ribbed beams according to the present invention.

[0038] Among them, 11-groove, 12-rib beam, 13-transverse steel bar, 14-longitudinal steel bar, 15-stirrup, 121-rib beam groove, 122-through hole. DETAILED DESCRIPTION

[0039] Example 1

[0040] like Figure 1-7 and Fig. 9 A close-jointed precast concrete bidirectional composite floor with ribbed beams, wherein the upper surface of the composite floor is provided with three transverse, mutually parallel ribbed beams 12 made of reinforced concrete, and the ribbed beams 12 are integrally formed with the composite floor; a steel mesh is provided in the plate body of the composite floor, and the steel mesh is formed by binding a plurality of transverse steel bars 13 and a plurality of longitudinal steel bars 14, the two ends of the transverse steel bars 13 are exposed from the side of the composite floor, and the two ends of the longitudinal steel bars 14 are not exposed from the side of the composite floor; a plurality of longitudinally parallel grooves 11 are provided on both longitudinal sides of the upper surface of the composite floor, and the grooves 11 pass through the middle and lower parts of the ribbed beams 12 on the same side of the longitudinal edge of the upper surface of the composite floor, and the part of the groove 11 directly below the ribbed beam 12 is provided with a through hole 122.

[0041] The rib beam 12 is provided with two layers of transverse steel bars, each layer of which has two transverse steel bars, and the transverse steel bars of the upper and lower layers are tied together by a plurality of mutually parallel stirrups 15. The cross section of the rib beam 12 is trapezoidal. The upper surface of the rib beam 12 is provided with a plurality of evenly distributed rib beam grooves 121.

[0042] The middle and lower parts of the rib beams 12 in the middle of the upper surface of the composite floor are provided with a plurality of longitudinal through holes 122. The through hole 122 is a section of pre-buried corrugated pipe. The number of through holes 122 in the rib beams 12 in the middle of the upper surface of the composite floor is less than the number of through holes 122 in the rib beams 12 at the edges of the upper surface of the composite floor.

[0043] The upper surface of the composite floor slab is a rough surface.

[0044] The composite floor slab is a middle slab. When in use, both longitudinal sides of the composite floor slab are not placed on beams or walls, and need to form a steel bar lap connection with adjacent composite floor slabs.

[0045] Example 2

[0046] like Figure 8 As shown, a close-jointed precast concrete bidirectional composite floor slab with ribbed beams is different from the structure of Example 1 in that the composite floor slab is an edge plate, and only one of the two longitudinal sides of the upper surface of the composite floor slab is provided with a plurality of longitudinally parallel grooves. When in use, of the two longitudinal sides of the composite floor slab, the side with the grooves is not placed on the beam or wall, and needs to form a steel bar lap connection with the adjacent composite floor slab; the side without the grooves is placed on the beam or wall.

[0047] Example 3

[0048] The construction method of the close-assembled precast concrete bidirectional composite floor slab with ribbed beams of Example 1 or 2 is specifically as follows:

[0049] Two adjacent closely-joined precast concrete two-way composite slabs are closely-joined and arranged. The horizontal lap steel bars (straight bars) are passed through the corrugated tubes in the rib beams at the edge of the slab and placed in the grooves of the two adjacent closely-joined precast concrete two-way composite slabs. The embedded wires are passed through the through holes in the rib beams in the middle of the slab and the through holes in the rib beams at the edge of the slab. After the arrangement is completed, the upper steel mesh is laid and concrete is poured to form a cast-in-place layer of the composite slab.

[0050] The embodiments described above are merely descriptions of preferred implementation modes of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A construction method for a close-jointed precast concrete bidirectional composite floor slab with ribbed beams, characterized in that: The upper surface of the composite floor slab is provided with a plurality of transverse, mutually parallel reinforced concrete rib beams (12), the rib beams (12) and the composite floor slab being integrally formed; the cross section of the rib beams (12) is trapezoidal; the upper surface of the rib beams (12) is provided with a plurality of evenly distributed rib beam grooves (121); A steel mesh is provided in the body of the composite floor slab, the steel mesh being formed by binding a plurality of transverse steel bars (13) and a plurality of longitudinal steel bars (14), the two ends of the transverse steel bars (13) being exposed from the side of the composite floor slab, and the two ends of the longitudinal steel bars (14) not being exposed from the side of the composite floor slab; At least one of the two longitudinal sides of the upper surface of the composite floor slab is provided with a plurality of longitudinally parallel grooves (11), the grooves (11) passing through the middle and lower part of at least one rib beam (12), and a through hole (122) is provided in the portion of the groove (11) located directly below the rib beam (12); The construction method is as follows: two adjacent closely-joined precast concrete two-way composite slabs are closely joined and arranged, the lap steel bars are passed through the through holes in the rib beams at the edge of the slab, and placed in the grooves of the two adjacent closely-joined precast concrete two-way composite slabs, and the embedded wires are passed through the through holes in the rib beams in the middle of the slab and the through holes in the rib beams at the edge of the slab. After the arrangement is completed, the upper steel mesh is laid, and concrete is poured to form a cast-in-place layer of the composite slab.

2. The construction method of the close-jointed precast concrete bidirectional composite floor slab with ribbed beams according to claim 1 is characterized in that: The rib beam (12) is provided with an upper and lower layer of transverse steel bars, each layer of transverse steel bars having two steel bars, and the upper and lower layers of transverse steel bars are tied together by a plurality of mutually parallel stirrups (15).

3. The construction method of the close-jointed precast concrete bidirectional composite floor slab with ribbed beams according to claim 2 is characterized in that: A plurality of longitudinal through holes (122) are provided in the middle and lower parts of the rib beam (12) located in the middle of the upper surface of the composite floor slab.

4. The construction method of the close-jointed precast concrete bidirectional composite floor slab with ribbed beams according to claim 3 is characterized by: The number of through holes (122) in the rib beams (12) in the middle of the upper surface of the composite floor slab is less than the number of through holes (122) in the rib beams (12) at the edges of the upper surface of the composite floor slab.

5. The construction method of the close-jointed precast concrete bidirectional composite floor slab with ribbed beams according to claim 4 is characterized in that: The upper surface of the composite floor is a rough surface.

6. The construction method of the close-jointed precast concrete bidirectional composite floor slab with ribbed beams according to claim 5 is characterized in that: When the composite floor slab is an edge slab, only one of the two longitudinal sides of the upper surface of the composite floor slab is provided with a plurality of longitudinally parallel grooves (11).

7. The construction method of the close-jointed precast concrete bidirectional composite floor slab with ribbed beams according to claim 5 is characterized by: When the composite floor slab is a middle slab, a plurality of longitudinally parallel grooves (11) are provided on both longitudinal sides of the upper surface of the composite floor slab.

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