Crossed hollow grid beam

Abstract

The utility model discloses a crossed hollow grid beam, and belongs to the technical field of building structure engineering. The crossed hollow grid beam comprises a plurality of crossed hollow beam prefabricated units, and a lower suspension beam B and an upper suspension beam B between every two adjacent crossed hollow beam prefabricated units in the crossed hollow beam prefabricated units are connected through suspension beam cast-in-place sections. The crossed hollow beam prefabricated units are prefabricated and processed in a factory standardization mode, the construction quality of key joints such as beam-beam connecting points is guaranteed, meanwhile, the structural bearing capacity of the crossed hollow grid beam is improved, and the problems that a lower suspension beam is inconvenient to construct, the construction period is long, and decoration pipelines are holed are solved; and full-assembly green construction in a real sense is realized.

Description

Technical Field

[0001] The utility model relates to a cross hollow grid beam and belongs to the technical field of building structure engineering. Background Art

[0002] Concrete cross hollow beams are mainly used in civil residential buildings, large-span public buildings or industrial plants. Existing concrete cross hollow beam construction is mostly cast on site, mainly divided into one or more castings. One-time casting has very high requirements on the fluidity of concrete. The cross hollow beam structure is relatively complex. Since the lower suspension beam of the cross hollow beam is a large-span frame beam structure, the height of the short column is relatively prominent, and it is blocked by the hollow belly position so that it does not have a construction working surface, resulting in great difficulty in the construction of the lower suspension beam position of the cross hollow beam; multiple castings will affect the short column and the upper suspension beam reinforcement. Therefore, both casting methods will affect the cross hollow beam to varying degrees in terms of construction period and structural bearing capacity. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a cross hollow grid beam.

[0004] The utility model is realized through the following technical solutions:

[0005] A cross hollow grid beam, comprising a plurality of cross hollow beam prefabricated units, wherein a lower suspension beam B and an upper suspension beam B between two adjacent cross hollow beam prefabricated units in the plurality of cross hollow beam prefabricated units are respectively connected via a suspension beam cast-in-place section.

[0006] The cross hollow beam prefabricated unit includes two cross-shaped short columns, and the four free ends of the two cross-shaped short columns are provided with lower suspension beams B and upper suspension beams B side by side, and the upper suspension beams B are located directly above the lower suspension beams B. The two cross-shaped short columns are symmetrically arranged, and the lower suspension beams B and upper suspension beams B at one end of one of the cross-shaped short columns are directly connected one by one with the lower suspension beams B and upper suspension beams B at one end of the other cross-shaped short column during the prefabrication process.

[0007] The free end of the lower suspension beam B is provided with a lower suspension beam outwardly extending longitudinal reinforcement B, and the free end of the upper suspension beam B is provided with an upper suspension beam outwardly extending longitudinal reinforcement B.

[0008] The free ends of the outwardly extending longitudinal reinforcement B of the lower cantilever beam and the outwardly extending longitudinal reinforcement B of the upper cantilever beam are both provided with external threads.

[0009] The top surface of the upper suspension beam B is coplanar with the upper end surface of the cross-shaped short column, and the bottom surface of the lower suspension beam B is coplanar with the lower end surface of the cross-shaped short column.

[0010] The top surface of the upper suspension beam B is pre-embedded with beam-slab connecting ribs C, and the exposed portion of the beam-slab connecting ribs C is in an inverted V shape.

[0011] The difference between the exposed height of the beam-slab connecting reinforcement C and the thickness of the cast-in-place floor slab is the thickness of the concrete protective layer.

[0012] The space between the lower suspension beam B and the upper suspension beam B at one longitudinal end of the cross hollow beam prefabricated unit is filled with concrete to form a solid cantilever beam.

[0013] The beneficial effects of the utility model are:

[0014] 1. The factory-standardized prefabrication of cross hollow beam prefabrication units ensures the construction quality of key nodes such as beam-beam connection points, while improving the structural bearing capacity of cross hollow grid beams, solving problems such as inconvenient construction of lower hanging beams, long construction period, and opening holes for decoration pipelines, thus realizing truly fully assembled green construction.

[0015] 2. The cross-shaped short column is included in the beam as a whole. There is no splicing or cast-in-place concrete at the cross-shaped short column. The cross hollow beam prefabricated unit has a stable structure, good shear resistance, strong bearing capacity, and can meet the needs of large-span buildings. The cross hollow beam prefabricated unit is produced in batches according to factory standards, with good quality and fast processing. It will not disturb other prefabricated components during installation, which improves the quality of the cross hollow grid beam. The cross hollow beam prefabricated unit can be prefabricated in advance as needed and directly installed after being transported to the construction site, which greatly shortens its production and installation cycle, and also greatly reduces on-site cast-in-place wet operations, which has better environmental benefits and saves manpower and material resources.

[0016] 3. The cross hollow beam prefabricated unit can be cast in the mold at one time, and the two cross-shaped short columns are manufactured and processed in the factory. Compared with the traditional concrete prefabricated components, the complex beam-beam connection is included in the factory prefabrication, and the quality is more guaranteed. Compared with the traditional frame beam of the same height, the spanning capacity is better, that is, for the same span, the cross hollow beam prefabricated unit is smaller in height than the solid frame beam, which can gain a larger indoor clearance and make full use of the building space.

[0017] 4. The two cross-shaped short columns are manufactured and processed in the factory, which not only improves the structural stiffness of the cross hollow beam prefabricated unit, but also makes up for the loss of bending stiffness of the cross hollow beam prefabricated unit due to the reduction of height, and can also ensure the quality of the structural nodes; it solves the problems of loss of bending stiffness of the concrete cross hollow beam structure, difficulty in casting the nodes, and uneven quality of various components caused by on-site casting.

[0018] 5. Rectangular hollow spaces are left inside the cross hollow beam prefabricated units and between adjacent cross hollow beam prefabricated units, which can save a lot of building materials and save costs. In addition, rectangular hollow spaces can be used for pipeline installation, which can effectively shorten the construction period, reduce construction costs, and improve environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a cross hollow beam prefabricated unit of the utility model when a solid cantilever beam is provided on the cross hollow beam prefabricated unit;

[0020] Figure 2 It is a structural schematic diagram of the utility model when there is no solid cantilever beam on the cross hollow beam prefabricated unit;

[0021] Figure 3 It is a structural schematic diagram of a prefabricated cross hollow beam building floor including cross hollow grid beams;

[0022] Figure 4 is a schematic diagram of the column structure;

[0023] Figure 5 This is a schematic diagram of the structure of the precast beam.

[0024] In the figure: 1-column, 112-precast solid web beam, 113-extending longitudinal reinforcement of solid web beam; 2-precast beam, 210-lower suspension beam A, 212-extending longitudinal reinforcement A of lower suspension beam, 213-extending longitudinal reinforcement A of upper suspension beam; 3-cross hollow grid beam, 30-precast unit of cross hollow beam, 300-cross short column, 301-lower suspension beam B, 302-upper suspension beam B, 303-extending longitudinal reinforcement B of lower suspension beam, 304-extending longitudinal reinforcement B of upper suspension beam, 305-beam-slab connecting reinforcement C, 306-solid web cantilever beam, 307-beam-column cast-in-place section A, 31-suspended beam cast-in-place section; 6-beam body cast-in-place section B. DETAILED DESCRIPTION

[0025] The technical solution of the utility model is further described below, but the scope of protection required is not limited to the description.

[0026] Cross hollow beam structures are often used in large-span concrete structures. Since the concrete beam is hollow and the beam height is only 1 / 15 to 1 / 30 of the span, the beam structure height is significantly lower than the beam height of the traditional concrete structure (1 / 12 to 1 / 14), thereby increasing the effective net height of the room. At the same time, the large-span concrete cross hollow beam building floor structure can also be built into multi-story or high-rise buildings, realizing the transformation of horizontal spreading of large-span concrete cross hollow beam building floors into vertical building, which is the so-called "industrial building" concept. Not only can the building structure space be used more efficiently, but more importantly, a large amount of land can be saved, which can be greatly developed in the future construction field.

[0027] like Figures 1 to 5 As shown, a cross hollow grid beam described in the utility model, the cross hollow grid beam 3 includes a plurality of cross hollow beam prefabricated units 30, and the lower suspension beam B301 and the upper suspension beam B302 between two adjacent cross hollow beam prefabricated units 30 in the plurality of cross hollow beam prefabricated units 30 are respectively connected by a suspension beam cast-in-place section 31.

[0028] When in use, the cantilever beam cast-in-place section 31 is used to wrap the upper cantilever beam extending longitudinal reinforcement B304 and sleeves in two adjacent intersecting hollow beam prefabricated units 30, and the lower cantilever beam extending longitudinal reinforcement B303 and sleeves in two adjacent intersecting hollow beam prefabricated units 30, and realize the connection between two adjacent upper cantilever beams B302 and two adjacent lower cantilever beams B301.

[0029] The cross hollow grid beam 3 has less cast-in-place concrete in its overall structure and has stronger integrity.

[0030] The cross hollow beam prefabrication unit 30 is prefabricated in a standardized factory to ensure the construction quality of key nodes such as beam-beam connection points, while improving the structural bearing capacity of the cross hollow grid beam 3, solving the problems of inconvenient construction of lower hanging beams, long construction period, and opening holes for decoration pipelines, thus realizing truly fully assembled green construction.

[0031] The cross hollow beam prefabricated unit 30 includes two cross-shaped short columns 300, and the four free ends of the two cross-shaped short columns 300 are provided with lower suspension beams B301 and upper suspension beams B302 side by side, and the upper suspension beam B302 is located directly above the lower suspension beam B301. The two cross-shaped short columns 300 are symmetrically arranged, and the lower suspension beam B301 and the upper suspension beam B302 at one end of one of the cross-shaped short columns 300 are directly connected one by one with the lower suspension beam B301 and the upper suspension beam B302 at one end of the other cross-shaped short column 300 during the prefabrication process.

[0032] The cross-shaped short column 300 is included in the beam as a whole. There is no splicing or cast-in-place concrete at the cross-shaped short column 300. The cross hollow beam prefabricated unit 30 has a stable structure, good shear resistance, strong bearing capacity, and can meet the needs of large-span buildings. The cross hollow beam prefabricated unit 30 is produced in batches according to factory standards, has good quality, fast processing, and will not disturb other prefabricated components during installation, which improves the quality of the cross hollow grid beam 3. The cross hollow beam prefabricated unit 30 can be prefabricated in advance as needed and directly installed after being transported to the construction site, which greatly shortens its production and installation cycle, and also greatly reduces on-site cast-in-place wet operations, which has better environmental benefits and saves more manpower and material resources.

[0033] The cross hollow beam prefabricated unit 30 can be cast in a mold at one time, and the two cross-shaped short columns 300 are manufactured and processed in the factory. Compared with traditional concrete prefabricated components, the complex beam-beam connections are included in the factory prefabrication, and the quality is more guaranteed. Compared with traditional frame beams of the same height, the spanning capacity is better, that is, for the same span, the cross hollow beam prefabricated unit 30 is smaller in height than the solid frame beam, which can gain a larger indoor clearance and make full use of the building space.

[0034] Manufacturing and processing the two cross-shaped short columns 300 in the factory not only improves the structural rigidity of the cross hollow beam prefabricated unit 30, but also makes up for the loss of bending rigidity of the cross hollow beam prefabricated unit 30 due to the reduction in height, and can also ensure the quality of the structural nodes; it solves the problems of loss of bending rigidity of the concrete cross hollow beam structure, difficulty in casting the nodes, and uneven quality of various components due to on-site casting.

[0035] Rectangular hollow spaces are provided inside the cross hollow beam prefabricated units 30 and between adjacent cross hollow beam prefabricated units 30, which can save a lot of building materials and save costs. In addition, the rectangular hollow spaces can be used for pipeline installation, which can effectively shorten the construction period, reduce construction costs, and improve environmental benefits.

[0036] The free end of the lower suspension beam B301 is provided with a lower suspension beam outwardly extending longitudinal reinforcement B303, and the free end of the upper suspension beam B302 is provided with an upper suspension beam outwardly extending longitudinal reinforcement B304. The lower suspension beam outwardly extending longitudinal reinforcement B303 and the upper suspension beam outwardly extending longitudinal reinforcement B304 are both stress-bearing steel bars.

[0037] The free ends of the lower cantilever beam outwardly extending longitudinal reinforcement B303 and the upper cantilever beam outwardly extending longitudinal reinforcement B304 are both provided with external threads.

[0038] The top surface of the upper suspension beam B302 is coplanar with the upper end surface of the cross-shaped short column 300 , and the bottom surface of the lower suspension beam B301 is coplanar with the lower end surface of the cross-shaped short column 300 .

[0039] The top surface of the upper suspension beam B302 is pre-embedded with beam-slab connecting ribs C305, and the exposed portion of the beam-slab connecting ribs C305 is in an inverted V shape.

[0040] The exposed height of the beam-slab connecting rib C305 differs from the thickness of the cast-in-place floor slab by the thickness of the concrete protective layer. The beam-slab connecting rib C305 is pre-buried at the top of the upper suspension beam B302, which is convenient for quickly identifying the position of the cross hollow beam prefabricated unit 30, and convenient for on-site hoisting of the cross hollow beam prefabricated unit 30. The cross hollow beam prefabricated unit 30 can also be connected to the cast-in-place floor slab as a whole, which can increase the construction speed, shorten the construction period, and reduce the construction cost.

[0041] The lower suspension beam B301 and the upper suspension beam B302 at one longitudinal end of the cross hollow beam prefabricated unit 30 are filled with concrete to form a solid cantilever beam 306. The longitudinal end of the cross hollow beam prefabricated unit 30 is made into a solid cantilever beam 306. Compared with the combination of the lower suspension beam B301 and the upper suspension beam B302, the solid cantilever beam 306 has improved overall stiffness and bearing capacity; the cantilever beam extending longitudinal reinforcement at the solid cantilever beam 306 is connected to the prefabricated solid beam extending longitudinal reinforcement 113 at the prefabricated solid beam 112 on the column 1 through a sleeve, which can also further improve the overall stiffness of the connection between the solid cantilever beam 306 and the prefabricated solid beam 112; finally, after support, local cast-in-place concrete is used to connect the solid cantilever beam 306 and the prefabricated solid beam 112, so as to make up for the problem of overall bending stiffness loss of the cross hollow grid beam 3 due to the height reduction.

[0042] A method for manufacturing and installing a cross hollow grid beam comprises the following steps:

[0043] Step 1: Assemble the prefabricated template of the cross hollow beam prefabrication unit 30, and arrange the longitudinal reinforcement, stirrups and beam-slab connecting reinforcement C305 according to the design;

[0044] Step 2: Measure and locate the longitudinal reinforcement, stirrups and beam-slab connecting reinforcement C305, and then tie the reinforcement according to the design;

[0045] Step 3: pour concrete into the prefabricated formwork and vibrate the concrete to make it dense;

[0046] Step 4: After the concrete and precast formwork are cured to the specified strength, the precast formwork is removed;

[0047] Step 5: After the cross hollow beam prefabricated unit 30 is transported to the construction site, it is hoisted to the designed position by a crane, and for the cross hollow beam prefabricated unit 30 provided with a solid cantilever beam 306, the solid cantilever beam 306 is directed toward the side center column, and then the lower suspension beam B301 and the upper suspension beam B302 of all the cross hollow beam prefabricated units 30 are placed correspondingly;

[0048] Step 6: Set up a support frame at the bottom of the two cross-shaped short columns 300 on each cross hollow beam prefabricated unit 30;

[0049] Step 7: Connect the lower suspension beam outward longitudinal reinforcement B303 and the upper suspension beam outward longitudinal reinforcement B304 in two adjacent cross hollow beam prefabricated units 30 through sleeves to form the main frame of the cross hollow grid beam 3, and connect the solid web cantilever beam 306 outward longitudinal reinforcement, the lower suspension beam outward longitudinal reinforcement B303 and the upper suspension beam outward longitudinal reinforcement B304 on the outermost circle of the cross hollow beam prefabricated units 30 of the main frame of the cross hollow grid beam 3 through sleeves, correspondingly to the prefabricated solid web beam outward longitudinal reinforcement 113 on the column 1, the lower suspension beam outward longitudinal reinforcement A212 and the upper suspension beam outward longitudinal reinforcement A213 on the prefabricated beam 2;

[0050] Step 8: Position and correct the precast beam 2 and the cross hollow beam precast unit 30, and then use a template to cast concrete in the connection section between the solid cantilever beam 306 and the column 1 to form a beam-column cast-in-place section A307;

[0051] Step nine: erect formwork and pour concrete into the connection section between the lower cantilever beam B301 and the lower cantilever beam A210, and the connection section between two adjacent lower cantilever beams B301, to form the beam body cast-in-place section B6 and the cantilever beam cast-in-place section 31 accordingly.

[0052] Most of the existing large-span cross hollow beam structures are constructed using cast-in-place concrete. Generally, a one-time formwork support system is used and concrete is poured in batches. However, due to the inconvenience of construction, the construction speed is reduced to a certain extent. In addition, it is very easy to have unstable component connections, resulting in the structure not meeting the use requirements, thereby increasing construction costs.

[0053] During the construction of the cross hollow grid beam, there is no need to set up a construction platform for workers, which saves the time of setting up and dismantling the construction platform and ensures the safety of workers. The factory standardizes the prefabrication of the cross hollow beam prefabrication unit 30, which ensures the construction quality of key nodes such as beam-beam connection points, solves the problems of inconvenient construction of lower hanging beams, long construction period, and opening holes for decoration pipelines, and realizes the real full assembly green construction.

[0054] The length of the prefabricated beam 2 is consistent with the length of the cross hollow beam prefabricated unit 30, and the length of the cross hollow beam prefabricated unit 30 is twice its own width;

[0055] The cast-in-place concrete used in the beam-column cast-in-place section A307, the beam body cast-in-place section B6 and the cantilever beam cast-in-place section 31 is micro-expansive concrete that is one grade higher than that of the prefabricated components.

[0056] The length of the precast beam 2 is consistent with the length of the cross hollow beam precast unit 30, and the length of the cross hollow beam precast unit 30 is twice its own width, which helps the factory to standardize the production of precast components such as the cross hollow beam precast unit 30 and the precast beam 2; at the same time, the lengths of the beam-column cast-in-place section A307, the beam body cast-in-place section B6 and the cantilever beam cast-in-place section 31 are consistent, which facilitates the simultaneous positioning and construction of the cross hollow beam precast unit 30 and the precast beam 2.

[0057] The fully assembled construction of the cross hollow grid beam 3 effectively solves the problems of inconvenient construction platform erection and cast-in-place construction of the lower suspended beam, and the long construction period. By using cast-in-place micro-expansive concrete that is one grade higher than the prefabricated components at the assembly nodes, it can not only ensure the mechanical properties of the connection, but also save material costs.

[0058] Specifically, the template is a steel template, and the support frame is a steel pipe bracket constructed by using steel pipes.

Claims

1. A cross hollow grid beam, characterized in that: The cross hollow grid beam (3) comprises a plurality of cross hollow beam prefabricated units (30), wherein the lower suspension beam B (301) and the upper suspension beam B (302) between two adjacent cross hollow beam prefabricated units (30) in the plurality of cross hollow beam prefabricated units (30) are respectively connected via a suspension beam cast-in-place section (31).

2. The cross hollow grid beam according to claim 1, characterized in that: The cross hollow beam prefabricated unit (30) comprises two cross-shaped short columns (300), the four free ends of the two cross-shaped short columns (300) are provided with lower suspension beams B (301) and upper suspension beams B (302) side by side, and the upper suspension beams B (302) are located directly above the lower suspension beams B (301), the two cross-shaped short columns (300) are symmetrically arranged, and the lower suspension beams B (301) and the upper suspension beams B (302) at one end of one of the cross-shaped short columns (300) are directly connected one by one with the lower suspension beams B (301) and the upper suspension beams B (302) at one end of the other cross-shaped short column (300) during the prefabrication process.

3. The cross hollow grid beam according to claim 2, characterized in that: The free end of the lower suspension beam B (301) is provided with a lower suspension beam outwardly extending longitudinal reinforcement B (303), and the free end of the upper suspension beam B (302) is provided with an upper suspension beam outwardly extending longitudinal reinforcement B (304).

4. The cross hollow grid beam according to claim 2, characterized in that: The free ends of the lower cantilever beam outwardly extending longitudinal reinforcement B (303) and the upper cantilever beam outwardly extending longitudinal reinforcement B (304) are both provided with external threads.

5. The cross hollow grid beam according to claim 2, characterized in that: The top surface of the upper suspension beam B (302) and the upper end surface of the cross-shaped short column (300) are coplanar, and the bottom surface of the lower suspension beam B (301) and the lower end surface of the cross-shaped short column (300) are coplanar.

6. The cross hollow grid beam according to claim 2, characterized in that: The top surface of the upper suspension beam B (302) is pre-buried with beam-slab connecting ribs C (305), and the exposed portion of the beam-slab connecting ribs C (305) is in an inverted V shape.

7. The cross hollow grid beam according to claim 6, characterized in that: The exposed height of the beam-slab connecting reinforcement C (305) differs from the thickness of the cast-in-place floor slab by the thickness of the concrete protective layer.

8. The cross hollow grid beam according to claim 2, characterized in that: Concrete is filled between the lower suspension beam B (301) and the upper suspension beam B (302) at one longitudinal end of the cross hollow beam prefabricated unit (30) to form a solid cantilever beam (306).

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