CN114876190A - Method and device for intercepting high-strength concrete in beam - Google Patents

Abstract

The invention discloses a method and a device for intercepting high-strength concrete in a beam, wherein the method comprises the following steps: determining an interception position: the part which is half of the height of the column boundary beam and is not less than 500mm is used as the joint surface of high-strength and low-strength grade concrete; installing an intercepting device: selecting one beam stirrup as a positioning stirrup; after the stirrups are installed, a plurality of deformed steels are arranged between two beam main reinforcements which are adjacent in the transverse direction, the deformed steels are arranged at the positions of the reinforcement protection layers on the two sides of the beam respectively, the deformed steels are installed in an inclined mode, the deformed steels and the stirrups are installed at an angle of 45 degrees, and the upper portions of the deformed steels are fixed with the stirrups; reinforcing steel bars which are smaller than the beam main bars by one grade are arranged between two vertically adjacent beam main bars; installing a screw at the lower opening of the template: a screw is arranged at the bottom of the beam and traverses the beam template, and the lower part of the deformed steel bar is abutted against the screw; and (6) pouring concrete. The invention can avoid the disordered flowing of the high-strength concrete and improve the interception quality of the high-strength concrete.

Description

Method and device for intercepting high-strength concrete in beam

technical field

The invention relates to the field of building construction, in particular to a method and a device for intercepting high-strength concrete in a beam.

Background technique

With the rapid development of the construction industry, in order to ensure the design requirements of "strong columns, weak beams and strong joints", concrete of different strength grades are designed in the beam-column joint area of the structure to ensure the seismic resistance of the structure. In order to improve the construction quality of intercepting high-strength concrete in the beam and ensure the structural construction quality of the beam-column joint area and the aesthetics of the concrete, the existing construction method will cause the concrete to flow and crack in the joint area, affecting the quality and appearance of the concrete structure. Effect.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a method and device for intercepting high-strength concrete in a beam, which can avoid disorderly flow of high-strength concrete and improve the interception quality of high-strength concrete.

To achieve the above object, the present invention provides the following technical solutions:

A method for intercepting high-strength concrete in a beam, comprising the following steps:

(1) Determine the interception position: the half distance from the column side beam height and not less than 500mm is used as the interface of high and low strength grade concrete, that is, the interception surface;

(2) Installation of intercepting device: select one of the beam stirrups located at half the distance from the column side beam height and not less than 500mm as the positioning stirrup; after the stirrup installation is completed, the horizontally adjacent two beam main bars A plurality of rebars are arranged between the two sides of the beam, and one rebar is set at the position of the steel bar protection layer on both sides of the beam. The rebar is installed at an inclination, the rebar and the stirrup are installed at 45°, and the upper part of the rebar is fixed with the stirrup; Between the main reinforcement of two adjacent beams, there is a steel bar one grade smaller than the main reinforcement of the beam;

(3) Installation of screw at the bottom of the template: a screw is set at the bottom of the beam, the screw traverses the beam template, and the lower part of the rebar is in contact with the screw;

(4) Concrete pouring: first, use a concrete pump to transport the column grade concrete in place and vibrate it in layers, reserve a 45° inclined plane at the floor beam slab, remove the intercepting device and the screw when the concrete is initially set, and then Pump concrete for pouring beam slabs.

Preferably, in the step (2), the stirrups are arranged at a distance of 30 cm from the edge of the column.

Preferably, in the step (2), the stirrups are bound with binding wires, and the binding spacing is 10 cm.

Preferably, in the step (2), the threaded steel is a third-grade threaded steel with a diameter of 16 mm, and the upper part of the threaded steel and the stirrup are firmly bound by binding wires.

Preferably, in the step (2), the length of the upper opening of the rebar should be 50mm higher than the top surface of the beam.

Preferably, in the step (2), the steel bars are bound with the threaded steel bars on both sides thereof.

Preferably, in the step (3), the diameter of the screw is 18 mm.

Preferably, in the step (3), the outer casing of the screw is provided with a plastic sleeve.

Preferably, in the step (4), the method of removing the intercepting device and the screw is as follows: loosen the tie wire that binds the upper opening of the rebar and the stirrup, and hit the rebar 50mm higher than the upper opening of the concrete with a hammer to let the thread The steel is loose, and it is convenient to take out the rebar, and then remove the screw.

A high-strength concrete interception device in a beam, comprising a beam main reinforcement and a beam formwork, and further comprising:

For positioning stirrups, select one of the beam stirrups located at half the distance from the column side beam height and not less than 500mm as the positioning stirrup;

Rebar, multiple rebars are arranged between the main bars of two adjacent beams in the transverse direction, and one rebar is set at the position of the steel bar protection layer on both sides of the beam; the rebar and the stirrup are installed at an inclination of 45°, and the upper part of the rebar is installed. fixed with stirrups;

Reinforcing bars, the reinforcing bars are respectively arranged between the main bars of two adjacent beams in the vertical direction;

The screw rod is arranged at the bottom of the beam, the screw rod traverses the beam template, and the lower part of the threaded steel is in contact with the screw rod.

Compared with the prior art, the beneficial effects of the present invention are:

1) The present invention reasonably arranges the intercepting device, and sets up blocking facilities on the formwork to avoid disorderly flow of high-strength concrete and improve the interception quality of high-strength concrete.

2) The present invention ensures the strength of the concrete in the node area, avoids the flow and cracking of the concrete in the node area, and improves the visual effect of the concrete structure.

3) The intercepting device is simple to manufacture, easy to install and disassemble, improves work efficiency, has strong applicability, and can be widely used in complex beam-column joint areas.

4) The present invention is suitable for the project in which the beam-column node area in the frame structure and the frame shear wall structure is constructed by concrete of different strength grades.

Description of drawings

Fig. 1 is the position location diagram of intercepting device in Embodiment 1 of the present invention;

2 is an elevation view of the intercepting device in Embodiments 1 and 2 of the present invention;

3 is a side view of the intercepting device in Embodiments 1 and 2 of the present invention;

Fig. 4 is the installation diagram of the blocking screw in Embodiment 1 of the present invention;

Fig. 5 is the intercepting diagram of high-strength concrete in the beam in the embodiment 1 of the present invention;

In the figure, 1. High-strength concrete for columns, 2. Low-strength concrete for beams and slabs, 3. Rebars, 4. Screws, 5. Frame columns, 6. Beam main bars, 7. Positioning stirrups, 8. Steel bars.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

A method for intercepting high-strength concrete in a beam, and the construction process is as follows:

Construction preparation → determine the position of the intercepting device → production of the intercepting device → installation of the intercepting device → installation of the blocking screw at the lower mouth of the beam formwork → high-strength concrete pouring → removal of the intercepting device → concrete pouring of the beam and slab.

1. Construction preparation

(1) In order to ensure the quality of the project, the construction personnel should be familiar with the construction drawings in advance, understand the construction content, and be familiar with the relevant requirements for concrete of different strengths in the beam-column joint area of the national codes, standards and atlases.

(2) Configure necessary construction equipment, prepare construction equipment and installation materials, and do a good job in product protection after construction.

(3) Before construction, the technical person in charge shall make technical disclosure to the on-site construction personnel, so as to better control the quality and meet the specification requirements.

2. Determine the location of the interceptor

(1) As shown in Figure 1, in order to enhance the shear resistance of the core area of the column node, a distance (h/2) from the column side beam height and ≥ 500mm is used as the interface of high and low strength grade concrete (intercepting device). installation).

(2) The on-site personnel calculate the position of the interface of high and low strength grade concrete according to the drawings, and then mark the beam steel bar with red paint (marks should be made on the top and bottom of the intercepting device), and the beam steel bar is placed in the formwork and re-check the relevant data, so as to avoid large errors in the process of lowering the steel bars.

3. Intercepting device production and installation

(1) As shown in Figure 4, select the beam stirrup 30cm away from the side of the column (frame column 5) as the positioning stirrup 7.

(2) The positioning stirrups 7 are bound with binding wires, and the binding spacing is 10cm.

(3) As shown in Figure 2-3, after the installation of the positioning stirrup 7 is completed, the installation of the intercepting device is carried out.

(4) The threaded steel 3 is arranged between the two adjacent beam main bars 6 in the lateral direction. During installation, the third-grade threaded steel 3 with a diameter of 16mm is installed vertically at 45° on the positioning stirrup 7 and tied firmly with binding wires.

(5) The length of the upper mouth of the tertiary rebar 3 of the intercepting device should be 50mm higher than the top surface of the beam to ensure that the intercepting device can be easily taken out before the concrete is initially set.

(6) Two 3-grade rebars 3 of φ16mm must be installed at the position of the steel bar protection layer on both sides of the beam to avoid the phenomenon of slurry leakage on the side during concrete pouring. Vertically adjacent two beam main bars 6 are bound with steel bars 8 and rebars 3 that are one grade smaller than the beam main bars.

4. Installation of the screw at the bottom of the beam formwork

(1) As shown in Figure 4, in order to ensure the stability of the intercepting device and avoid loosening during concrete pouring, it is necessary to set a screw 4 of φ18mm at the bottom of the beam to fix the lower part of the skeleton steel bar.

(2) The installation position of the screw 4 is the lower port of the steel skeleton, the screw is located below the bottom rib of the beam, and the lower port of the intercepting device is against the lower screw 4 to ensure the stability of the steel skeleton during concrete pouring.

5. High-strength concrete pouring, interception device removal and beam-slab concrete pouring

(1) The concrete pouring and tamping method in the beam-column joint area is as follows: first, use a concrete pump to transport the column-grade concrete (ie, column high-strength concrete 1) in place and vibrate in layers, leaving a 45° inclined plane at the floor beam slab. , when the concrete is initially set, the intercepting device (including the rebar 3 and the steel bar 8) and the screw rod 4 are removed, and the beam formwork at the hole of the screw rod 4 is repaired, and then the concrete for pouring the beam plate (that is, the beam plate is low strength concrete 2). The interception of high-strength concrete in the beam is shown in Figure 5.

(2) When pouring and ramming floor column, beam and slab concrete, the flow of high-strength grade concrete and the problem of cold joints of high and low strength adjoining surfaces should be controlled.

(3) When the concrete labels of beams and columns differ greatly, the mix ratio design should be carried out to meet the requirements of concrete strength grade and pumpability.

(4) After the concrete is poured, it should be covered and watered within 12 hours.

6. After the high-strength concrete in the beam is poured, the intercepting device is removed

(1) Before the concrete reaches the initial setting, remove the intercepting device, loosen the binding wire of the upper opening of the rebar 3 and the positioning stirrup 7, and hit the rebar 3 50mm above the upper opening of the concrete with a hammer to let the rebar 3 3 Loose, easy to take out the steel frame.

(2) Before removing the intercepting device, the screw 4 should be removed first. In order to facilitate the removal of the screw 4, a plastic sleeve can be added outside the screw 4, and the plastic sleeve does not need to be removed. The related materials after dismantling can be cleaned up for the next use.

7. Quality control standards

(1) Check the raw materials before construction, and have a certificate of conformity and a re-test report witnessing sampling, and check the construction process, technological process, and testing process.

(2) The allowable deviation of the production and installation of the intercepting device shall comply with the provisions of Table 1.

Table 1 Interceptor fabrication and installation allowable deviation (mm)

Example 2

As shown in Figures 2 and 3, an in-beam interception device for high-strength concrete includes beam main bars 6 and beam formwork, and also includes:

Positioning stirrup 7, select one of the beam stirrups located at half the distance from the column side beam height and not less than 500mm as the positioning stirrup 7;

Threaded steel 3, a plurality of threaded steels 3 are arranged between two adjacent beam main bars 6 in the transverse direction, and a threaded steel 3 is respectively set at the position of the reinforcing bar protection layer on both sides of the beam; the threaded steel 3 and the stirrup 7 are at 45° Inclined installation, the upper part of the threaded steel 3 is fixed with the positioning stirrup 7;

Reinforcing bars 8, the reinforcing bars 8 are respectively arranged between the two adjacent beam main bars 6 in the vertical direction;

The screw 4, the screw 4 is arranged at the bottom of the beam, the screw 4 traverses the beam template, and the lower part of the screw steel 3 is in contact with the screw 4.

Principle: During the construction of concrete with different strength grades in the beam-column joint area, the concrete is poured according to the principle of high concrete strength first, then low, and column first, then beam slab. After the concrete pouring in the beam-column core area is completed, the intercepting device is removed, and the beam-slab concrete is poured, thereby ensuring the concrete strength of the beam-column joint area and avoiding shear damage and cracks in the beam-column joint area due to the flow of high-strength concrete.

The above content is only an example and description of the structure of the present invention. Those skilled in the art can make various modifications or supplements to the specific embodiments described or replace them in a similar manner, as long as they do not deviate from the structure of the present invention. Or beyond the scope defined by the claims, all belong to the protection scope of the present invention.

Claims (10)

1. A method for intercepting high-strength concrete in a beam is characterized by comprising the following steps:

(1) determining an interception position: the part which is half of the height of the pillar boundary beam and is not less than 500mm is used as the interface of high-strength and low-strength concrete, namely a blocking section;

(2) installing an intercepting device: selecting one beam stirrup which is positioned at a half distance from the height of the column boundary beam and is not less than 500mm as a positioning stirrup; after the stirrups are installed, a plurality of deformed steels are arranged between two beam main reinforcements which are adjacent in the transverse direction, the deformed steels are arranged at the positions of the reinforcement protection layers on the two sides of the beam respectively, the deformed steels are installed in an inclined mode, the deformed steels and the stirrups are installed at an angle of 45 degrees, and the upper portions of the deformed steels are fixed with the stirrups; reinforcing steel bars which are smaller than the beam main bars by one grade are arranged between two vertically adjacent beam main bars;

(3) installing a screw at the lower opening of the template: a screw is arranged at the bottom of the beam and traverses the beam template, and the lower part of the deformed steel bar is abutted against the screw;

(4) pouring concrete: the concrete pump is used for conveying the concrete of the column grade to be in place and vibrating in layers, a 45-degree inclined plane is reserved at the beam slab of the floor, the intercepting device and the screw rod are removed when the concrete is initially set, and then the concrete for pouring the beam slab is pumped.

2. The method for intercepting high-strength concrete in a beam according to claim 1, wherein the method comprises the following steps: in the step (2), the stirrups are arranged at the positions 30cm away from the column sides.

3. The method for intercepting high-strength concrete in a beam according to claim 1, wherein the method comprises the following steps: in the step (2), the stirrups are bound by binding wires, and the binding distance is 10 cm.

4. The method for intercepting high-strength concrete in a beam according to claim 1, wherein the method comprises the following steps: in the step (2), the deformed steel bar is a three-level deformed steel bar with the diameter of 16mm, and the upper part of the deformed steel bar is firmly bound with the stirrup through the binding wire.

5. The method for intercepting high-strength concrete in a beam according to claim 1, wherein the method comprises the following steps: in the step (2), the length of the upper opening of the deformed steel bar is 50mm higher than the top surface of the beam.

6. The method for intercepting high-strength concrete in a beam according to claim 1, wherein the method comprises the following steps: and (3) binding the steel bars with the deformed steel bars on the two sides in the step (2).

7. The method for intercepting high-strength concrete in a beam according to claim 1, wherein the method comprises the following steps: in the step (3), the diameter of the screw is 18 mm.

8. The method for intercepting high-strength concrete in a beam according to claim 1, wherein the method comprises the following steps: and in the step (3), a plastic sleeve is sleeved outside the screw rod.

9. The method for intercepting high-strength concrete in a beam according to claim 1, wherein: in the step (4), the intercepting device and the screw rod dismounting method are that the binding wires for binding the upper opening of the deformed steel bar and the stirrups are loosened, the deformed steel bar 50mm higher than the upper opening of the concrete is knocked by a hammer to loosen the deformed steel bar, the deformed steel bar is conveniently taken out, and then the screw rod is dismounted.

10. The utility model provides an in roof beam to high strength concrete intercepting device, includes girder main muscle and beam formwork, its characterized in that still includes:

positioning stirrups, wherein one beam stirrup positioned at a position which is half of the height of the column boundary beam and not less than 500mm is selected as the positioning stirrup;

the beam comprises deformed steel bars, a plurality of deformed steel bars and a plurality of reinforcing steel bars, wherein the plurality of deformed steel bars are arranged between two beam main bars which are adjacent in the transverse direction; the deformed steel bar and the stirrup are obliquely arranged at an angle of 45 degrees, and the upper part of the deformed steel bar is fixed with the stirrup;

the reinforcing steel bars are respectively arranged between two vertically adjacent beam main reinforcements;

and the screw rod is arranged at the bottom of the beam, the screw rod transversely penetrates through the beam template, and the lower part of the deformed steel bar abuts against the screw rod.

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