A rib-key fully spliced assembled integral steel-concrete composite open-web sandwich slab and method

Abstract

The invention discloses an assembled integral steel-concrete composite open-web sandwich slab for assembling single precast reinforced concrete upper and lower ribs at steel pipe shear keys, which comprises steel pipe shear keys, precast reinforced concrete lower ribs, precast reinforced concrete superimposed upper ribs and surface concrete thin plates. The lower ribs are connected with the steel pipe shear keys by double screw sleeves. After all the double screw sleeve connections of the lower ribs are completed, concrete is cast in situ for the second time at the connection points. The superimposed upper ribs are connected with the steel pipe shear keys by double screw sleeves. After all the double screw sleeve connections of the upper ribs are completed, the surface thin plate concrete and the upper rib composite layer concrete are finally cast at one time, so that the steel pipe shear keys, the upper and lower ribs and the surface thin plates form an integral to work together. The assembling unit of the invention is simple and light in manufacture and easy to hoist; the unit transportation does not require special supports and is convenient for transportation; the full-sleeve connection on site makes it easy to ensure the construction quality and the construction speed is fast; the structure has large stiffness and excellent mechanical and economic performances.

Description

Technical Field

[0001] The present invention relates to a building structure in the field of civil engineering, in particular to a rib-key fully spliced assembled monolithic steel-concrete composite open-web sandwich slab floor and a preparation method thereof. Background Art

[0002] Since the successful development of reinforced concrete open-web sandwich slabs in 1995, reinforced concrete open-web sandwich slabs have the characteristics of light self-weight, small structural height, the ability to pass through water and electricity pipelines in the open web, beautiful appearance, excellent economic performance, and the use of this structure can build multi-story or high-rise large-span building structures, thus greatly saving land. By 2021, this structural form has been successfully applied in more than 20 provinces, municipalities and autonomous regions across the country, and 3 local regulations have been successfully compiled, creating good social and economic benefits.

[0003] In recent years, due to the high construction noise and pollution during on-site concrete pouring, and the increasing labor costs, the pace of promoting building assembly in various regions of China has gradually accelerated. For example, Beijing requires that by 2020, the proportion of prefabricated buildings should account for more than 30% of the total number of newly built buildings. Since the reinforced concrete open-web sandwich slab is composed of shear keys, upper and lower ribs and a surface concrete thin slab, due to the particularity and complexity of its structure, if the cast-in-place method is used for construction, the construction process is relatively complex and the formwork consumption is huge. The above factors have forced the reinforced concrete open-web sandwich slab structure to develop towards the prefabricated or assembled monolithic direction.

[0004] The invention creation with the application number 201710005411.3 and the name of large-span prefabricated hybrid steel open-web sandwich slab floor and manufacturing method discloses an open-web sandwich slab floor and its manufacturing method for making and assembling units in different regions and assembling them on site, which has promoted the assembly process of open-web sandwich slabs and realized the assembly application of steel open-web sandwich slabs.

[0005] For steel open-web sandwich slabs and reinforced concrete open-web sandwich slabs, the internal force and deformation distribution laws under load are the same, only the materials are different. Since in the service stage of the reinforced concrete open-web sandwich slab, the overall bending moment of the slab is manifested as the pressure or tension received by the upper and lower ribs, and at the same time, there is a very small local bending moment in the upper and lower ribs, and the inflection point of the ribs approximately appears near the midpoint position, so it can be considered to divide the whole open-web sandwich slab into different regions and number them. The regions with the same number have the same shape and size, and are truncated at the midpoint position of the upper and lower ribs and processed in the prefabrication factory. For steel open-web sandwich slabs, the assembled units are transported to the site and strongly connected with high-strength bolts at the truncated positions; for reinforced concrete open-web sandwich slabs, the steel bars are connected with straight thread sleeves at the connection nodes, and concrete is poured secondarily at the connection nodes, and finally the concrete thin slab is poured.

[0006] The above assembly technology for reinforced concrete open-web sandwich plates has achieved very remarkable results, greatly reducing the on-site construction workload. The precast units are processed in the factory, and the quality is well guaranteed. However, there are still some aspects that need to be improved urgently. For example, the deficiency of the above-mentioned assembly method of fabricating and assembling units in regions is that the shear keys and the upper and lower ribs of the assembled units are cast together, and the steel bar binding and formwork installation are complex; the self-weight of the assembled units is large, which is not conducive to hoisting; the size of the assembled units is large, the transportation is difficult, and special supports need to be made during transportation to avoid damage to the assembled units caused by bumps during transportation; at the on-site splicing joints, formwork needs to be installed on-site and then concrete is cast again, etc. Summary of the Invention

[0007] The purpose of the present invention is to provide a rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate floor and its preparation method. The present invention solves the problems of many and complex on-site construction procedures, slow construction speed, and large consumption of formwork and supports in cast-in-place reinforced concrete open-web sandwich plates; the present invention is an assembled integral structure, the assembled unit has a simple and light structure, is easy to hoist, convenient for transportation, the on-site construction is simple, and the efficiency is high.

[0008] The technical solution of the present invention: A rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate floor, including a grid frame, a solid web side beam surrounding the edge of the grid frame, and a concrete thin plate covering the surface of the solid web side beam and the grid frame; the grid frame is spliced by a plurality of assembled units; the assembled unit includes upper ribs and lower ribs arranged in upper and lower layers, and one ends of the upper and lower ribs are correspondingly connected to the upper and lower parts of the same side wall of the shear key; the other ends of the upper and lower ribs are correspondingly connected to the upper and lower parts of the same side wall of the shear key of another assembled unit, so as to form an assembled structure; each assembled unit is spliced with each other according to the assembled structure described above, and finally a grid frame is formed.

[0009] In the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate floor described above, the ends of the upper and lower ribs and the side wall of the shear key are connected by double screw sleeves.

[0010] In the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate floor described above, a U-shaped steel plate that semi-surrounds the connection position between the ends of the upper and lower ribs and the side wall of the shear key is provided.

[0011] In the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate floor described above, the concrete filled in the connection position semi-surrounded by the U-shaped steel plate is cast on-site.

[0012] In the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate floor described above, the upper rib is a precast composite beam; the precast composite beam includes a precast beam and a composite layer provided on the upper surface of the precast beam; the concrete of the composite layer is cast on-site.

[0013] In the above-mentioned rib-key fully spliced assembled integral steel-concrete composite open-web sandwich floor slab, internal stiffening plates are provided at the top of the shear key and at the connection positions between the shear key and the upper and lower ribs.

[0014] The manufacturing method of the above-mentioned rib-key fully spliced assembled integral steel-concrete composite open-web sandwich floor slab includes the following steps:

[0015] S1. Determine the floor slab plane size and grid size, and locate the layout points of the shear keys by positioning and setting out the lines.

[0016] S2. Prefabricate the upper ribs, lower ribs and shear keys.

[0017] S3. Transport the upper and lower ribs and shear keys to the site for assembly into a grid frame, and anchor the reserved steel bars at the edge nodes of the grid frame into the solid web side beam.

[0018] S4. Pour the concrete at the connection position between the lower rib and the shear key.

[0019] S5. Bind the concrete thin plate formwork and tie the steel bars of the concrete thin plate.

[0020] S6. Pour the concrete of the concrete thin plate and the solid web side beam on site and then cure and remove the formwork.

[0021] In step S5 of the above-mentioned manufacturing method, when tying the steel bars of the concrete thin plate, the head and tail of the longitudinal steel bars of the superimposed layer arranged on the same axis are sequentially connected through double screw sleeves.

[0022] In step S6 of the above-mentioned manufacturing method, the concrete of the superimposed layer and the concrete thin plate are poured synchronously.

[0023] In the above-mentioned manufacturing method, shear studs are welded on the bottom, side surfaces inside the U-shaped steel plate at the connection position between the upper and lower ribs and the top surface of the shear key before concrete pouring.

[0024] Beneficial effects: Compared with the prior art, in the present invention, single precast reinforced concrete upper and lower ribs are assembled at the shear keys to form a grid frame (i.e., the main load-bearing structure of the floor slab), and then the concrete thin plate is poured, and finally an assembled integral steel-concrete composite open-web sandwich floor slab structure is formed, which has the following advantages:

[0025] (1) For the assembled integral steel-concrete composite open-web sandwich floor slab with a common span (within 30 m) in the present invention, the grid frame within the solid web side beam is composed of precast reinforced concrete upper and lower ribs and shear keys; the main load-bearing members of the floor slab are single precast concrete upper and lower ribs, which can be precast in the factory in advance, greatly reducing the complexity of on-site construction, reducing the usage amount of formwork, and improving the construction efficiency.

[0026] (2) The present invention well inherits the advantages of cast-in-situ reinforced concrete open-web sandwich slabs, such as small self-weight, strong spanning ability, small structural height, beautiful appearance, the ability to pass through water and electricity pipelines in the open web, flexible partition division, and good economic performance.

[0027] (3) The present invention is an assembled integral floor structure, which combines the advantages of prefabricated buildings and cast-in-situ structures, conforms to the spirit of promoting building prefabrication, building industrialization and green construction in China, and the cast-in-situ concrete thin slab improves the overall performance of the prefabricated open-web sandwich slab.

[0028] (4) The prefabricated assembling unit of the present invention is the upper and lower ribs with double screw sleeves and shear keys. The types of assembling unit components are few, the self-weight is small, and the factory production is simple.

[0029] (5) The shape of the prefabricated assembling unit of the present invention is simple, and it can be closely arranged on the transport vehicle and transported to the construction site. No special support is required for the assembling unit during transportation.

[0030] (6) Due to the small self-weight of the prefabricated assembling unit of the present invention, the on-site hoisting is simple and no large hoisting equipment is required.

[0031] (7) All the prefabricated assembling units of the present invention are connected by double screw sleeves at the construction site, and only a small amount of stud welding work is carried out on-site. The construction quality is easy to guarantee and the construction speed is fast.

[0032] (8) The shear key of the present invention is a steel pipe shear key, there is no problem of shear key cracking, and the elastic modulus of the steel is high. Under the same cross-sectional dimensions, the shear bearing capacity of the shear key can be controlled by controlling the wall thickness of the steel pipe. Its shear stiffness is greater than that of ordinary reinforced concrete shear keys, thereby increasing the overall stiffness of the open-web sandwich slab, and the mechanical properties are excellent.

[0033] (9) A large amount of formwork and supports can be saved during the construction of the present invention, the construction speed is fast, the construction period is greatly saved, and the economic performance is good.

[0034] (10) The upper rib of the present invention is a precast composite beam, and the concrete of the composite layer and the concrete thin slab are poured synchronously at the construction site; this structure can make the combination between the concrete thin slab and the upper rib of the floor better, enhance the integrity of the floor, and further enhance the stiffness of the floor.

[0035] (11) The structural stiffness of the rib-key fully spliced type assembled integral steel-concrete composite open-web sandwich slab floor of the present invention is basically the same as that of the cast-in-situ reinforced concrete open-web sandwich slab floor; compared with the cast-in-situ reinforced concrete open-web sandwich slab floor, its construction period can be shortened by about 1 / 3.

[0036] Compared with the traditional precast concrete open-web sandwich slab, the assembled unit of the present invention is simple to manufacture, light in weight, and easy to hoist; special supports are not required for unit transportation, and the transportation is convenient; full-sleeve connection is used on site, the on-site construction is simple, the construction quality is easy to guarantee, and the construction speed is fast.

[0037] In summary, the present invention not only retains the advantages of the traditional open-web sandwich slab, such as small self-weight, small structural floor height, good economic performance, and strong spanning ability, but also solves the problems of many on-site construction processes, complexity, slow construction speed, large consumption of formwork and supports in the cast-in-place reinforced concrete open-web sandwich slab, greatly improving the construction speed, ensuring the construction quality, and having excellent mechanical and economic performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is the overall plan view of the assembled integral open-web sandwich slab of the present invention, and the dotted box is an assembled unit;

[0039] Figure 2 It is the structural schematic diagram after the construction of a connection node of the grid of the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich slab of the present invention;

[0040] Figure 3 It is the exploded view of the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich slab of the present invention;

[0041] Figure 4 It is the structural schematic diagram of the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich slab of the present invention when the concrete at the connection of the lower rib and the shear key and the concrete of the surface thin plate are not poured;

[0042] Figure 5 It is the structural schematic diagram of the single precast superimposed upper rib with partial pouring of the present invention;

[0043] Figure 6 It is the structural schematic diagram of the single precast lower rib with complete pouring of the present invention;

[0044] Figure 7 It is the structural schematic diagram of the steel pipe shear key welded with U-shaped steel plate and internal stiffening plate of the present invention;

[0045] Figure 8 It is the sectional view of the steel pipe shear key welded with U-shaped steel plate and internal stiffening plate of the present invention;

[0046] Figure 9 It is the structural schematic diagram of the steel bar connection relationship between the upper and lower ribs at the side bay and the reinforced concrete solid side beam at the side node of the present invention;

[0047] Figure 10 It is the structural schematic diagram of the steel bar connection relationship between the solid beam at the side bay, the solid side beam and the precast upper and lower ribs of the present invention;

[0048] Reference numerals: 1 - concrete thin plate, 2 - upper rib, 3 - lower rib, 4 - shear key, 5 - U-shaped steel plate, 6 - longitudinal reinforcement, 7 - stirrup, 8 - double screw sleeve, 9 - internal stiffening plate, 10 - solid web side beam, 11 - grid frame, 12 - assembly unit, 13 - frame column, 14 - precast beam, 15 - composite layer. Specific implementation mode

[0049] The present invention will be further described below in conjunction with the embodiments and the drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work shall fall within the scope of protection of the present invention.

[0050] Embodiment 1. A rib-key fully spliced assembled integral steel-concrete composite open-web sandwich floor slab, the composition is as Figures 1 - 10 shown, including a grid frame 11, the edge of the grid frame 11 is surrounded by a solid web side beam 10, and the surface of the solid web side beam 10 and the grid frame 11 is covered with a concrete thin plate 1; the grid frame 11 is composed of a plurality of assembly units 12 spliced together; the assembly unit 12 includes upper and lower ribs 2 arranged in upper and lower layers, and one end of the upper and lower ribs is correspondingly connected to the upper and lower parts of the same side wall of the shear key 4; the other end of the upper and lower ribs is correspondingly connected to the upper and lower parts of the same side wall of the shear key 4 of another assembly unit 12, so as to form an assembled structure; between each assembly unit 12, they are spliced with each other according to the described assembled structure, and finally the grid frame 11 is formed.

[0051] The ends of the upper and lower ribs are connected to the side wall of the shear key 4 through a double screw sleeve 8.

[0052] A U-shaped steel plate 5 that semi-surrounds it is provided at the connection position between the ends of the upper and lower ribs and the side wall of the shear key 4.

[0053] The concrete filled inside the connection position semi-surrounded by the U-shaped steel plate 5 is cast on site.

[0054] The aforementioned upper rib 2 is a precast composite beam; the precast composite beam includes a precast beam 14 and a composite layer 15 provided on the upper surface of the precast beam 14; the concrete of the composite layer 15 is cast on site.

[0055] At the top of the aforementioned shear key 4, and at the connection positions between the shear key 4 and the upper and lower ribs, internal stiffening plates 9 are provided; the inside of the shear key 4 can be a hollow structure or a solid structure with concrete poured after drilling holes in the internal stiffening plate 9.

[0056] The aforementioned method for manufacturing the floor slab includes the following steps:

[0057] S1. Determine the plane size and grid size of the floor slab, and locate and lay out the lines to find the layout points of the shear key 4;

[0058] S2. Prefabricate the upper rib 2, lower rib 3 and shear key 4;

[0059] S3. Transport the upper and lower ribs and the shear key 4 to the site for assembly into the grid frame 11, and anchor the steel bars reserved at the edge nodes of the grid frame 11 into the solid web side beam 10;

[0060] S4. Pour the concrete at the connection position of the lower rib 3 and the shear key 4;

[0061] S5. Assemble the formwork of the concrete thin plate 1 and bind the steel bars of the concrete thin plate 1;

[0062] S6. Pour the concrete of the concrete thin plate 1 and the solid web side beam 10 on site and then cure and remove the formwork.

[0063] In step 5, when binding the steel bars of the concrete thin plate 1, the head and tail of the longitudinal bars 6 of the superimposed layer 15 arranged on the same axis are sequentially connected by double screw sleeves 8 synchronously.

[0064] In step 6, the concrete of the superimposed layer 15 and the concrete thin plate 1 are poured synchronously.

[0065] Shear studs have been welded on the bottom, side surfaces inside the U-shaped steel plate 5 at the connection position of the upper and lower ribs and the top surface of the shear key 4 before the concrete pouring.

[0066] Example 2. A rib-key fully spliced assembled monolithic steel-concrete composite open-web sandwich floor slab, the composition is as Figures 1 - 10 shown, including a precast lower rib 3, a precast superimposed upper rib 2, a shear key 4 connecting the upper and lower ribs, and a concrete thin plate 1; the grid frame formed by the upper and lower ribs connecting the shear key 4 can be orthogonally placed or orthogonally and obliquely placed; the upper rib 2 and the shear key 4 are connected by a double screw sleeve 8, the stirrups 7 and longitudinal bars 6 of the superimposed upper rib 2 are prefabricated in the factory together with the precast beam 14, and the concrete of the superimposed layer 15 is cast in place on site; the lower rib 3 and the shear key 4 are also connected by a double screw sleeve 8; at the connection position of the upper and lower ribs and the shear key 4, that is, the periphery of the double screw sleeve 8 connection position, a U-shaped steel plate 5 is arranged, the U-shaped steel plate 5 is prefabricated together with the shear key 4, and the post-cast concrete inside the U-shaped steel plate 5 and the concrete of the concrete thin plate 1 are in the form of on-site casting; the shear key 4 is a steel pipe shear key.

[0067] Specifically, when prefabricating the shear key 4, U-shaped steel plates 5 are welded at the upper and lower positions on the side walls around the shear key 4; stiffening plates 9 are welded inside the shear key 4, and the elevation of the internal stiffening plates 9 of the shear key 4 is the same as the elevation of the longitudinal bar axes of the upper and lower ribs.

[0068] The manufacturing method of the aforesaid floor slab includes the following steps:

[0069] S1. Determine the floor slab plane size and grid size, and locate and lay out the lines to find the shear key layout points;

[0070] S2. Prefabricate the upper rib 2, lower rib 3 and shear key 4 of reinforced concrete;

[0071] S3. Connect the prefabricated lower rib 3 and shear key 4 with a double screw sleeve 8;

[0072] S4. Weld shear studs on the bottom and side surfaces inside the lower U-shaped steel plate 5, and pour the post-cast concrete in the connection area between the shear key and the lower rib;

[0073] S5. Connect the upper rib 2 and shear key 4 with a double screw sleeve 8, and at the same time, connect the longitudinal bars 6 at the head and tail in the superposed layer of the upper rib 2 on the same axis with double screw sleeves 8 in sequence;

[0074] S6. Weld shear studs on the bottom and side surfaces inside the upper U-shaped steel plate 5 and on the top surface of the steel pipe shear key;

[0075] S7. Assemble the formwork of the concrete thin plate 1, bind the thin plate reinforcement, and check the concealed works;

[0076] S8. Cast the concrete for the superposed layer of the upper rib 2 and the concrete thin plate 1 on site;

[0077] S9. Cure the concrete and remove the formwork to form a rib-key fully spliced assembled integral steel-concrete composite grid floor slab.

[0078] Example 3. A rib-key fully spliced assembled integral steel-concrete composite grid floor slab, the composition is as Figures 1 - 10 shown, including a reinforced concrete solid web side beam 10 and a grid frame 11 installed in the solid web side beam 10. The grid frame 11 is composed of a plurality of assembled units 12 spliced with each other. The assembled unit 12 includes a prefabricated reinforced concrete lower rib 3, a prefabricated superposed upper rib 2 and a steel pipe shear key 4; the grid frame 11 anchors the reserved steel bars of the side ribs (the upper and lower ribs at the edge) into the side beam at the side nodes and pours the concrete together with the side beam.

[0079] The sizes of the above-mentioned same type of assembled units 12 are all the same, and the assembled unit 12 is simple to manufacture.

[0080] The above-mentioned grid frame is connected by double screw sleeves between the assembled units 12, and finally the concrete thin plate 1 of the grid floor slab is cast.

[0081] The lower rib 3 described above is a reinforced concrete beam with a complete casting, an outer sleeve with double screw sleeves at both ends, and an inner sleeve; the superimposed upper rib 2 is divided into two parts. One part is a precast pre-cast part, which is a reinforced concrete beam with an outer sleeve with double screw sleeves at the longitudinal bars at both ends and an inner sleeve. The other part is the superimposed layer of the precast reinforced concrete superimposed beam. The concrete of the superimposed layer is cast on-site together with the concrete thin plate 1 to form an integral body; the shear key is a steel pipe shear key. After all the lower ribs and the steel pipe shear keys are connected with double screw sleeves, the concrete pouring sequence is as follows: first, the concrete at the connection position of the secondary cast-in-place lower rib 3 is poured, then the precast superimposed upper rib is installed, and finally the concrete of the superimposed layer and the concrete of the surface thin plate are poured together.

[0082] The various assembled units of the above grid frame are connected by double screw sleeves, and the concrete at the connection between the side rib and the solid web side beam 10 is poured together to form a monolithic joint.

[0083] Example 4. The schematic diagram of the large-span rib-key fully spliced assembled integral steel-concrete composite open-web sandwich slab floor structure of the present invention is as Figures 1 - 10 shown Figure 1 is the overall plan view of the assembled integral open-web sandwich slab of the present invention. The assembled integral open-web sandwich slab is a square grid frame structure, and the grid side length L = 2m. Figure 2 and 3 are respectively the schematic diagram and the exploded view of the grid connection node structure inside the reinforced concrete solid web side beam; it includes a solid web side beam 10 made of reinforced concrete structure arranged along the peripheral frame columns 13 of the building, precast reinforced concrete upper and lower ribs, steel pipe shear keys 4, and a concrete thin plate 1 cast in place on the surface layer.

[0084] See Figure 5 , the upper rib is a precast superimposed beam, which is a precast and assembled unit of reinforced concrete with partial casting and double screw sleeves. The precast section height (i.e., Figure 5 the height of the precast beam 14 in

[0085] See Figure 6 , the lower rib 3 is a reinforced concrete beam with complete casting, a double screw sleeve outer sleeve and 1 inner sleeve.

[0086] The present invention discloses a manufacturing method for a rib-key fully spliced assembled integral steel-concrete composite open-web sandwich slab floor applicable to common spans (within 30m), which specifically includes the following steps:

[0087] S1. Fabricate precast upper ribs and lower ribs in the factory. The fabrication methods of the upper ribs and the lower ribs are the same. First, bind the steel bar cages of the upper and lower ribs; then strip the threads at the ends of the longitudinal bars (or strip the threads in advance and then bind), screw double screw sleeves onto the ends of the longitudinal bars, and put on the protective sleeves of the double screw sleeves. SeeFigure 5 and Figure 6 ; finally, pour the concrete and cure it for future use.

[0088] S2. Fabricate precast steel pipe shear keys in the factory. Process the steel pipe shear keys welded with U-shaped steel plates and internal stiffening plates according to the drawings. The function of the U-shaped steel plate is to facilitate the positioning connection between the precast reinforced concrete ribs (i.e., the upper and lower ribs) and the steel pipe shear keys, and also to facilitate the pouring of the post-cast concrete in the connection area; then weld one of the inner sleeves of the double-screw sleeve to the steel pipe shear key. The welding elevation of the inner sleeve is the same as the elevation of the longitudinal bars of the precast ribs. Pay special attention to aligning the axis of the welded inner sleeve with the longitudinal bars; the function of the internal stiffening plate is to ensure the effective transfer of the axial force of the longitudinal bars and meet the shear strength requirements of the joint core area where the rib intersects with the shear key. Its welding elevation is the same as the axis of the inner sleeve and the longitudinal bars of the rib. See Figure 7 and Figure 8 .

[0089] S3. Set up a full hall scaffold at the construction site, install the side beam formwork and bind the side beam steel bars. At this time, the fabrication of the precast steel pipe shear keys and the precast upper and lower ribs is carried out synchronously.

[0090] S4. Conduct positioning and layout, and the precast components enter the site. After the full hall scaffold is set up and the side beam formwork and steel bar binding work are completed, conduct positioning and layout to find the layout points of the shear keys; number the precast units at the precast factory and transport them to the site.

[0091] S5. Assemble the precast units on site. First, arrange the steel pipe shear keys at the shear key positioning points; secondly, assemble the lower ribs. The lower ribs are connected to the steel pipe shear keys with double-screw sleeves. After all the double-screw sleeves of the lower ribs are installed, weld shear studs on the inner bottom surface and side surface of the U-shaped steel plate, and then pour the concrete inside the U-shaped steel plate; then assemble the upper ribs. The upper ribs are connected to the steel pipe shear keys with double-screw sleeves, and the longitudinal bars between the longitudinal bars of the upper rib composite layer are connected with double-screw sleeves, as Figure 4 shown; the longitudinal bars of the upper and lower rib side nodes at the side bays are anchored into the reinforced concrete solid web side beam, and the anchorage length needs to meet the design requirements. When the anchorage length is insufficient, mechanical anchorage measures can be considered. See Figure 9 and Figure 10 .

[0092] S6. Weld shear studs on the top of the steel pipe shear keys.

[0093] S7. Install the formwork of the concrete thin slab, bind the surface layer thin slab steel bars and check the concealed works.

[0094] S8. Cast the concrete inside the U-shaped steel plate at the connection between the upper rib and the steel pipe shear key, the concrete of the reinforced concrete surface thin plate, and the concrete of the reinforced concrete solid web side beam on-site at one time; to improve the structural integrity, the integral casting method can also be adopted. After all the formworks are assembled and the steel bars are tied, cast the concrete inside the U-shaped steel plate at the connection between the upper rib and the steel pipe shear key, the concrete of the reinforced concrete surface thin plate, the concrete of the reinforced concrete solid web side beam, and the concrete of the frame column 13 on-site at one time.

[0095] S9. Cure and remove the formwork.

[0096] Embodiment 5. To facilitate the understanding of the technical solution of the present invention by those skilled in the art, a detailed explanation is given below by citing an example of a proposed project:

[0097] The large-span floor of a lecture hall has a square plane, with its long side (Lx) being 20 m and its short side (Ly) being 20 m. The floor area of the lecture hall is 20 m × 20 m = 400 m 2 , and now the technical solution of the present invention is used to construct the floor of the lecture hall. The specific implementation plan is as follows: First, pour the frame columns 13 with a spacing of 6 m along the long side and short side directions of the lecture hall respectively, and then assemble the formwork of the reinforced concrete solid web side beam and tie the side beam steel bars. When assembling the side beam formwork, attention should be paid to reserving the interfaces for connecting the side beam with the upper and lower ribs, as Figure 9 shown; then install the internal full hall scaffolding; while constructing the side beam formwork and erecting the full hall scaffolding, the precast upper and lower ribs and steel pipe shear keys are also processed in the precast factory. The grid size of this embodiment is 2 m × 2 m, and the cross-section specification of the steel pipe shear key is □400 mm × 400 mm × 14 mm. The height of the steel pipe shear key is determined according to the stiffness and strength conditions that the floor should meet under the action of the load. Therefore, the net distance between the outer surfaces of the end plates on both sides of the upper and lower ribs is ln = 2000 mm - 400 mm = 1600 mm. Because a connection area of 150 mm for the double screw sleeve needs to be reserved, the precast length of the rib concrete is l 0 = ln - 150×2 = 1300 mm, as Figure 6 shown; next, transport the precast assembly units to the site, set up a construction platform on the top of the full hall scaffolding, place the steel pipe shear keys at the shear key positioning points, then first connect the nodes of the lower rib and the steel pipe shear key with double screw sleeves, and weld shear studs on the inner side and bottom surface of the U-shaped steel plate, and then pour the concrete inside the U-shaped steel plate of the lower rib. Next, install the upper rib, and its installation steps are the same as those of the lower rib, but the concrete inside the U-shaped steel plate is not poured first, as Figure 4 shown; next, assemble the formwork of the concrete thin plate of the open-web sandwich plate and tie its steel bars; then, check the concealed works, cast the concrete of the upper rib overlay layer 15, the concrete of the surface thin plate, and the concrete of the solid web side beam on-site, and then cure and remove the formwork. According to the above procedures, a lecture hall with a building plane size of 20 m × 20 m can be constructed.

[0098] Example 6. In this example, the processing procedure of the components of the long-span rib-key fully spliced assembled integral steel-concrete composite open-web sandwich slab floor structure is the same as that in Example 5, and the on-site construction method and sequence are basically the same as those in Example 5. The difference is that considering that the internal force distribution of the open-web sandwich slab under uniformly distributed vertical loads is similar to that of an ordinary solid-web reinforced concrete slab, the shear force of the side beams in the middle of the rectangular plane is relatively large, and the shear forces on the upper and lower ribs in the side bays are large. To improve the overall stiffness of the open-web sandwich slab and the shear stiffness of the side bays, some side-bay ribs can be made into cast-in-place reinforced concrete solid-web beams, such as Figure 10 shown.

[0099] To facilitate the understanding of the technical solution of the present invention by those skilled in the art, a detailed explanation is given below by citing an example of a proposed project:

[0100] The long-span floor of a lecture hall has a square plane, with its long side (Lx) being 20 m and its short side (Ly) being 20 m. The floor area of the lecture hall is 20 m × 20 m = 400 m 2 , and now the technical solution of the present invention is used to construct the floor of the lecture hall. The specific implementation plan is as follows: The specific construction procedure is basically the same as that in Example 5. The difference is that at the joints where some cast-in-place reinforced concrete solid-web beams replace the precast upper and lower ribs, the formwork and steel bar binding are constructed together with the side beams. However, when binding the formwork of the side-bay solid-web beams, an interface for connecting with the precast upper and lower ribs should be reserved at the beam ends, and the longitudinal bars of the precast upper and lower ribs should be anchored into the cast-in-place solid-web beams, and the anchorage length should meet the design requirements, such as Figure 10 shown; Next, bind the concrete thin slab of the open-web sandwich slab and tie its steel bars; Then, check the concealed works, and pour the concrete of the upper rib composite layer and the surface thin slab on-site, as well as the concrete of the solid-web side beams, and then cure and remove the formwork. According to the above procedures, a lecture hall with a building plane size of 20 m × 20 m can be constructed.

[0101] In summary, using the technology of the present invention to construct a long-span open-web sandwich slab floor not only retains various advantages of the traditional cast-in-place reinforced concrete open-web sandwich slab floor, but also improves the convenience of on-site construction, greatly shortens the construction period; the transportation of small components is convenient, saving transportation costs; most connections on-site use double-screw sleeves, and only the shear studs need to be welded with a welding torch, which can ensure the construction quality; under the same cross-sectional dimensions, the shear stiffness of the shear key can be controlled by controlling the wall thickness of the steel pipe shear key. Because the elastic modulus of steel is large, the shear stiffness of the shear key is greater than that of an ordinary reinforced concrete shear key, thus increasing the overall stiffness of the open-web sandwich slab, with excellent mechanical properties, and there is no need to worry about the crack problem of the shear key.

[0102] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Method for manufacturing rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate, characterized in that, the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate includes a grid frame (11), a solid web side beam (10) surrounds the edge of the grid frame (11), and a concrete thin plate (1) covers the surfaces of the solid web side beam (10) and the grid frame (11); the grid frame (11) is formed by splicing a number of assembling units (12); the assembling unit (12) includes upper ribs (2) and lower ribs (3) arranged in upper and lower layers, and one ends of the upper and lower ribs are correspondingly connected to the upper and lower parts of the same side wall of the shear key (4); the other ends of the upper and lower ribs are correspondingly connected to the upper and lower parts of the same side wall of the shear key (4) of another assembling unit (12), thereby forming an assembled structure; each assembling unit (12) is spliced with each other according to the assembled structure, and finally the grid frame (11) is formed; the ends of the upper and lower ribs are connected to the side wall of the shear key (4) through double screw sleeves (8); at the connection position between the ends of the upper and lower ribs and the side wall of the shear key (4), a U-shaped steel plate (5) that semi-surrounds it is provided; concrete is cast in situ in the connection position semi-surrounded by the U-shaped steel plate (5); the upper rib (2) is a precast composite beam; the precast composite beam includes a precast beam (14) and a composite layer (15) arranged on the upper surface of the precast beam (14); the concrete of the composite layer (15) is cast in situ; inner stiffening plates (9) are provided at the top of the shear key (4) and at the connection positions between the shear key (4) and the upper and lower ribs; the method for manufacturing the rib-key fully spliced assembled integral steel-concrete composite open-web sandwich plate includes the following steps: S1. Determine the floor slab plane size and grid size, and locate and set out the points for arranging the shear key (4); S2. Precast the upper ribs (2), lower ribs (3) and shear key (4); S3. Transport the upper and lower ribs and the shear key (4) to the site for assembly into a grid frame (11), and anchor the reserved steel bars at the edge nodes of the grid frame (11) into the solid web side beam (10); S4. Cast the concrete at the connection position between the lower rib (3) and the shear key (4); S5. Bind the formwork of the concrete thin plate (1) and tie the steel bars of the concrete thin plate (1); S6. Cast the concrete of the concrete thin plate (1) and the solid web side beam (10) in situ and then cure and remove the formwork; In step S5, when tying the steel bars of the concrete thin plate (1), the head and tail of the longitudinal bars (6) of the composite layer (15) arranged on the same axis are sequentially connected through double screw sleeves (8); In step S6, the concrete of the composite layer (15) and the concrete thin plate (1) are cast synchronously; Before the concrete is cast, shear studs are welded on the bottom, side surfaces inside the U-shaped steel plate (5) at the connection position between the upper and lower ribs and on the top surface of the shear key (4).

Images