Prestressed concrete laminated slab bottom plate and preparation method

Abstract

According to the prestressed concrete laminated slab bottom plate and the preparation method, by adopting a groove arrangement method, under the condition of double-layer reinforcement arrangement, the centers of two-way prestressed reinforcements are equivalent to the centers of the positions of the horizontal axes of the cross sections of two-way prestressed concrete slabs; the axial center of the transverse section of the bidirectional prestressed concrete slab is pressed, and the axial center of the longitudinal section of the groove position is pressed, so that the bottom plate of the prestressed concrete laminated slab can be effectively prevented from warping and cracking. The bottom plate of the bidirectional prestressed concrete laminated slab prepared by the method is simple in process, good in quality, high in efficiency and low in cost.

Description

Technical Field

[0001] The invention belongs to the technical field of housing construction engineering, and relates to concrete components and prefabrication technology, in particular to a prestressed concrete composite slab bottom plate and a preparation method thereof. Background Art

[0002] Prestressed concrete composite slab bottom plates are widely used for their good rigidity and crack resistance. At present, the commonly used prestressed concrete composite slab bottom plates are mainly unidirectionally prestressed. Due to the effect of the concrete Poisson's ratio, it is easy to produce cracks parallel to the prestressed steel bars in the bottom plates, which brings a certain degree of trouble to users. In order to overcome the cracking phenomenon caused by the concrete Poisson's ratio, it has become a trend to use bidirectional prestressing technology to prepare concrete composite slab bottom plates.

[0003] Invention patent application specification CN202310443873.9 discloses a "three-layer reinforced prestressed concrete composite slab bottom plate and preparation method". The three-layer reinforcement method is adopted so that the center of force of the unidirectional or bidirectional prestressing is on the center plane of the thickness direction of the bottom plate concrete or the offset is small, which can prevent the prefabricated bottom plate from warping and cracking. The concrete composite slab bottom plate prepared in this invention can use traditional hooks and concrete protective layer pads, or can use a hook assembly that prefabricates the hook and pad as one. The hook assembly can improve the anchoring effect of the hook and the reliability of lifting, facilitate the binding and fixing of the hook, prevent the pad from moving and causing the pad to fail, ensure that the pad plays the role that the traditional concrete protective layer pad should play, and ensure the thickness of the concrete protective layer is accurate. The invention is used to prepare the concrete composite slab bottom plate, which has a simple and mature process, good quality, high efficiency, low cost, safe and reliable lifting, and a large spacing between the required temporary supports for construction, which can save support and reduce the overall construction cost. However, the three-layer reinforcement is too complicated and cross-linked, and the calculated values ​​of the concrete cover thickness are too large in both directions, which should be improved. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a prestressed concrete composite slab bottom plate and a preparation method, which only requires two layers of reinforcement to achieve bidirectional prestressed steel bars to form compressive prestress in the center of the cross section, has a simple production process, and the composite slab bottom plate has good quality, low cost and excellent crack resistance.

[0005] The technical solution of the present invention is as follows: a prestressed concrete composite slab bottom plate, comprising: a bidirectional prestressed concrete slab, longitudinal prestressed steel bars, transverse prestressed steel bars, concrete and grooves, the transverse prestressed steel bars are arranged on the horizontal axis of the longitudinal section of the bidirectional prestressed concrete slab at the longitudinal groove, the longitudinal prestressed steel bars are arranged on the horizontal axis of the transverse section of the bidirectional prestressed concrete slab, and the upper surface of the concrete is provided with a longitudinal groove.

[0006] Furthermore, the grooves on the bidirectional prestressed concrete slab are arranged along the longitudinal length of the bidirectional prestressed concrete slab.

[0007] Furthermore, the longitudinal prestressed steel bars and the transverse prestressed steel bars of the bidirectional prestressed concrete slab are arranged in an interchangeable upper and lower layer positions. At this time, the groove is arranged along the transverse length of the bidirectional prestressed concrete slab.

[0008] A method for preparing a prestressed concrete composite slab bottom plate comprises the following steps:

[0009] S1 Arrange and tension prestressed steel bars

[0010] After cleaning the formwork and installing the side formwork, arrange the prestressed steel bars. First, arrange the transverse prestressed steel bars at the horizontal axis centerline of the longitudinal section at the longitudinal groove of the bidirectional prestressed concrete slab, and then arrange the longitudinal prestressed steel bars at the horizontal axis centerline of the transverse section of the bidirectional prestressed concrete slab; tension the longitudinal prestressed steel bars and the transverse prestressed steel bars and lock them;

[0011] S2 pouring concrete curing and demoulding

[0012] Pour concrete, make longitudinal grooves on the surface of the concrete, cure the concrete, release the prestress of the longitudinal prestressed steel bars and the transverse prestressed steel bars after the concrete reaches the designed strength, remove the side formwork, demould the bidirectional prestressed concrete slab, and complete the preparation of the prestressed concrete composite slab bottom plate.

[0013] Furthermore, a method for preparing a prestressed concrete composite slab bottom plate comprises the following steps:

[0014] S1 Arrange and tension prestressed steel bars

[0015] After cleaning the formwork and installing the side formwork, arrange the prestressed steel bars. First, arrange the longitudinal prestressed steel bars at the horizontal axis centerline of the transverse section at the transverse groove of the bidirectional prestressed concrete slab, and then arrange the transverse prestressed steel bars at the horizontal axis centerline of the longitudinal section of the bidirectional prestressed concrete slab; tension the longitudinal prestressed steel bars and the transverse prestressed steel bars and lock them;

[0016] S2 pouring concrete curing and demoulding

[0017] Pour concrete, make transverse grooves on the surface of the concrete, cure the concrete, release the prestress of the longitudinal prestressed steel bars and the transverse prestressed steel bars after the concrete reaches the designed strength, remove the side formwork, demould the bidirectional prestressed concrete slab, and complete the preparation of the prestressed concrete composite slab bottom plate.

[0018] The beneficial effects of the present invention are:

[0019] A prestressed concrete composite slab bottom plate and a preparation method thereof, by adopting a method of setting grooves, in the case of double-layer reinforcement, the center of the bidirectional prestressed steel bar is equivalent to the center of the horizontal axis line of the bidirectional prestressed concrete slab section, the transverse section of the bidirectional prestressed concrete slab is axially compressed, and the longitudinal section of the groove position is axially compressed, which can effectively prevent the prestressed concrete composite slab bottom plate from warping and cracking. The bidirectional prestressed concrete composite slab bottom plate is prepared by the present invention, with simple process, good quality, high efficiency and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a top view schematic diagram of the bidirectional prestressed concrete slab in the present invention;

[0021] Figure 2 is a schematic transverse cross-sectional view of a bidirectional prestressed concrete slab in the present invention;

[0022] Figure 3 It is a longitudinal cross-sectional schematic diagram of the bidirectional prestressed concrete slab at the longitudinal groove in the present invention;

[0023] In the figure, 1-bidirectional prestressed concrete slab, 2-longitudinal prestressed steel bars, 3-transverse prestressed steel bars, 4-concrete, 5-groove. DETAILED DESCRIPTION

[0024] It should be noted that in the description of the present invention, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", "clockwise", "counterclockwise", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction.

[0025] In the present invention, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connect" and the like should be understood in a broad sense. For example, "fixed" can be a fixed connection, a detachable connection, or an integral connection; the connection can be a mechanical connection or an electrical connection; the connection can be a direct connection or an indirect connection through an intermediate medium, and can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] A prestressed concrete composite slab bottom plate comprises a bidirectional prestressed concrete slab 1, longitudinal prestressed steel bars 2, transverse prestressed steel bars 3, concrete 4 and grooves 5. The bidirectional prestressed concrete slab 1 comprises longitudinal prestressed steel bars 2, transverse prestressed steel bars 3, concrete 4 and grooves 5; the longitudinal prestressed steel bars 2 are arranged on the horizontal axis of the transverse section of the bidirectional prestressed concrete slab 1, extending or not extending from the end of the bidirectional prestressed concrete slab 1; the transverse prestressed steel bars 3 are arranged on the horizontal axis of the longitudinal section at the longitudinal groove of the bidirectional prestressed concrete slab 1, extending or not extending from the end of the bidirectional prestressed concrete slab 1; the upper surface of the concrete 4 is provided with a groove 5; the groove 5 is arranged along the longitudinal length of the bidirectional prestressed concrete slab 1.

[0027] The longitudinal prestressed steel bars 2 and the transverse prestressed steel bars 3 in the bidirectional prestressed concrete slab 1 can be interchanged and arranged in upper and lower layers, and at this time, the groove 5 is arranged along the transverse length of the bidirectional prestressed concrete slab 1 .

[0028] A prestressed concrete composite slab bottom plate and a preparation method thereof, which is used to prepare the prestressed concrete composite slab bottom plate, comprises the following steps, which are performed in sequence:

[0029] Step 1: Arrange and tension prestressed steel bars

[0030] After cleaning the formwork and installing the side formwork, the prestressed steel bars are arranged. First, the transverse prestressed steel bars 3 are arranged at the horizontal axis centerline of the longitudinal section at the longitudinal groove on the bidirectional prestressed concrete slab 1, and then the longitudinal prestressed steel bars 2 are arranged at the horizontal axis centerline of the transverse section of the bidirectional prestressed concrete slab 1; the longitudinal prestressed steel bars 2 and the transverse prestressed steel bars 3 are tensioned and locked;

[0031] Step 2: Pour concrete and maintain the mold

[0032] Pour concrete 4, make longitudinal grooves on the surface of concrete 4, cure concrete 4, release the prestress of longitudinal prestressed steel bars 2 and transverse prestressed steel bars 3 after concrete 4 reaches the designed strength, remove the side formwork, demould the bidirectional prestressed concrete slab 1, and complete the preparation of the bottom plate of the prestressed concrete composite slab.

[0033] The above is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any modification, equivalent replacement and improvement made by any person skilled in the art within the technical scope disclosed by the present invention and within the spirit and principle of the present invention shall be covered within the protection scope of the present invention. At the same time, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

Claims

1. A prestressed concrete composite slab bottom plate, characterized in that: include: A bidirectional prestressed concrete slab (1), longitudinal prestressed steel bars (2), transverse prestressed steel bars (3), concrete (4) and grooves (5); the transverse prestressed steel bars (3) are arranged on the horizontal axis centerline of the longitudinal section of the bidirectional prestressed concrete slab (1) at the longitudinal groove; the longitudinal prestressed steel bars (2) are arranged on the horizontal axis centerline of the transverse section of the bidirectional prestressed concrete slab (1); and the upper surface of the concrete (4) is provided with a groove (5).

2. The prestressed concrete composite slab bottom plate according to claim 1, characterized in that: The groove (5) is arranged along the longitudinal length of the bidirectional prestressed concrete slab (1).

3. The prestressed concrete composite slab bottom plate according to claim 1, characterized in that: The longitudinal prestressed steel bars (2) and the transverse prestressed steel bars (3) are arranged in an interchangeable upper and lower layer positions, and at this time, the groove (5) is arranged along the transverse length of the bidirectional prestressed concrete slab (1).

4. A method for preparing a prestressed concrete composite slab bottom plate, characterized in that: The following steps are involved: S1 Arrange and tension prestressed steel bars After cleaning the formwork and installing the side formwork, the prestressed steel bars are arranged. First, the transverse prestressed steel bars (3) are arranged at the horizontal axis centerline of the longitudinal section at the longitudinal groove on the bidirectional prestressed concrete slab (1), and then the longitudinal prestressed steel bars (2) are arranged at the horizontal axis centerline of the transverse section of the bidirectional prestressed concrete slab (1); the longitudinal prestressed steel bars (2) and the transverse prestressed steel bars (3) are tensioned and locked; S2 pouring concrete curing and demoulding Concrete is poured, longitudinal grooves are made on the surface of the concrete (4), the concrete is cured, and after the concrete reaches the designed strength, the prestress of the longitudinal prestressed steel bars (2) and the transverse prestressed steel bars (3) is released, the side formwork is removed, and the bidirectional prestressed concrete slab (1) is demoulded, thereby completing the preparation of the prestressed concrete composite slab bottom plate.

5. A method for preparing a prestressed concrete composite slab bottom plate, characterized in that: The following steps are involved: S1 Arrange and tension prestressed steel bars After cleaning the formwork and installing the side formwork, the prestressed steel bars are arranged. First, the longitudinal prestressed steel bars (2) are arranged at the horizontal axis centerline position of the transverse section at the transverse groove on the bidirectional prestressed concrete slab (1), and then the transverse prestressed steel bars (3) are arranged at the horizontal axis centerline position of the longitudinal section of the bidirectional prestressed concrete slab (1); the longitudinal prestressed steel bars (2) and the transverse prestressed steel bars (3) are tensioned and locked; S2 pouring concrete curing and demoulding Concrete is poured, transverse grooves are made on the surface of the concrete (4), the concrete is cured, and after the concrete reaches the designed strength, the prestress of the longitudinal prestressed steel bars (2) and the transverse prestressed steel bars (3) is released, the side formwork is removed, and the bidirectional prestressed concrete slab (1) is demoulded, thereby completing the preparation of the prestressed concrete composite slab bottom plate.

Images