Cold connection steel truss concrete laminated slab

Abstract

The utility model discloses a cold connection steel truss concrete laminated slab. The cold connection steel truss concrete laminated slab comprises an upper flange with a hole groove, a steel web member and a concrete bottom plate. The opening of the upper flange with the hole groove is upward, and the bottom plate is provided with a hole corresponding to the web member; concrete is poured in the upper flange, and reinforcing steel bars are arranged in the upper flange; the steel web member penetrates through the upper flange through the upper flange hole groove; and the bottom of the steel web truss is arranged in the concrete bottom plate. Bottom plate steel bars composed of a plurality of longitudinal steel bars and transverse steel bars are arranged in the concrete bottom plate, and the transverse steel bars partially or completely penetrate through wave troughs of the web members. According to the steel truss concrete laminated slab, the web members are in cold connection with the upper chord members and the bottom plate to form the steel truss concrete laminated slab, energy consumption connection modes such as welding are not used, reliable connection, higher member strength, large member span and support-free distance and simple manufacturing can be achieved, industrial production of the members is achieved, the production efficiency of the members is improved, and energy consumption is reduced.

Description

Technical Field

[0001] The utility model specifically relates to the technical field of construction engineering, and particularly to a cold-connected steel truss concrete composite slab, which can be widely applied to the floor slabs of various buildings. Background Technique

[0002] There are particularly many existing prefabricated floor slab technologies, and the most commonly used ones include steel bar truss composite slabs, steel bar truss prestressed composite slabs, steel pipe truss prestressed composite slabs, etc. With the decreasing labor population in China, prefabricated structures need to save the supporting formwork wooden squares, and have higher requirements for the stiffness and strength of components, as well as higher requirements for industrial production.

[0003] Most of the existing technologies are the bottom plate plus truss ribs, making full use of the stiffness of the truss to reduce the thickness of the bottom plate and increase the stiffness and strength of prefabricated components. However, there are generally problems such as unreliable connections, low utilization rate of material strength, unreliable processing quality, troublesome processing, and being unsuitable for industrial production.

[0004] The patent "A New Type of Truss (CN 108560822 A)" proposes using concrete-filled steel tubes as the upper chord members and steel bars as the web members. The web members and the upper chord members are connected by spot welding, and there is only one weld at the connection, resulting in very low connection strength and reliability. Using steel tubes as the upper chord members, the contribution of the steel tubes to the stiffness of the floor slab is relatively low. To increase the stiffness, the steel tubes must be enlarged, and the cost will increase significantly. Concrete is filled in the steel tubes later. During processing, concrete needs to be poured first, then the truss is fixed on the formwork table, and then the bottom plate is poured, with two forming processes, resulting in low processing efficiency. Moreover, the connection between the poured concrete and the steel tubes is unreliable. Since concrete has a certain shrinkage, it is also difficult to control the compactness of the later-poured concrete. Therefore, the later-poured concrete cannot fully participate in the force-bearing of the components. As the span and load of the floor slab increase, there will inevitably be greater risks with this connection method.

[0005] The patent "Stereo Composite Truss Based on Steel Bar Truss and Its Manufacturing Method (CN 118148305 A)" uses a steel bar truss with a thin steel sheet added on it, and concrete is poured in the thin steel sheet. The connection between the web members and the upper and lower chord members is made by truss connection, and the thin steel sheet is in contact with the concrete of the upper flange. During production, the truss is made first, and then concrete is poured into the thin steel sheet groove. After the concrete solidifies, it is then flipped and placed on the bottom plate, requiring two concrete pours, with low efficiency; the connection relies on welding of the upper and lower chord steel bars, and the contact surface between the web members and the steel bars is very small. When the span and load are large, the connection reliability is not high and the bearing capacity is small. Since the thin steel sheet is open downward and has no direct connection with the web reinforcement, and only relies on concrete to transfer force, when the upper chord member is under compression, the steel sheet is relatively open due to the normal stress, and the steel sheet cannot act together with the upper chord member, resulting in low material utilization efficiency and being not conducive to cost reduction.

[0006] For the patent "Metal Plate and Concrete Composite Chord Truss Stiffened Composite Slab and the Planar Truss Used Therein (CN 116905711 A)", the connection scheme of the steel pipe web members and the upper chord members is selected. The upper and lower chord members are flat metal plates. The web members are welded to the upper chord members at the wave crests, and then the upper and lower chord members are respectively embedded in the concrete bottom slab and the upper chord concrete rib. Its connection method is similar to that of CN 118148305 A. Similarly, in the case of large-span heavy loads, the connection strength between the web members and the upper and lower chord members is not high, the reliability is low, and the component supports also need to be cast twice, resulting in low efficiency. Moreover, the connection uses a welding method, which greatly increases the energy consumption of component processing.

[0007] According to the above literature, in the existing technical solutions, the web reinforcement is continuously bent and welded or bolted to the upper chord member at the wave crest. The connection points are relatively weak, the processing energy consumption is high, the connection reliability is low, and it cannot meet the stress requirements of large-span heavy-load composite slabs. The ribs and the bottom slab need to be cast twice, resulting in low production efficiency and being not suitable for industrial production. The connection between the metal reinforcement of the upper chord member and the concrete is unreliable, and the composite upper chord member cannot fully exert its stress function. Utility Model Content

[0008] Therefore, the present utility model proposes a cold-connected steel truss concrete composite slab to solve the problems raised in the above background technology.

[0009] To achieve the above object, the present utility model discloses a cold-connected steel truss concrete composite slab, which includes: a perforated and grooved cold-formed thin steel upper flange, steel web members, and a concrete bottom slab. The perforated and grooved cold-formed thin steel upper flange has an upward opening, and concrete is poured later in the groove; the steel web members are bent to form continuous diagonal bars. The first diagonal bar and the second diagonal bar respectively pass through the perforated and grooved cold-formed thin steel upper flange and intersect above the bottom slab of the perforated and grooved cold-formed thin steel upper flange, forming an included angle of 20° to 80°, and are anchored in the later-poured concrete. The second diagonal bar and the third diagonal bar intersect to form an included angle of 20° to 80° and are anchored in the concrete bottom slab at the wave trough; a bottom slab steel mesh composed of a plurality of bottom slab longitudinal steel bars and transverse steel bars is arranged in the concrete bottom slab, and part or all of the transverse steel bars pass through above the wave trough and below the bottom slab longitudinal steel bars.

[0010] Further, as a preference, the perforated and grooved cold-formed thin steel upper flange is composed of two spliced L-shaped cold-formed thin steel plates. The cold-formed thin steel plates are provided with reserved holes and grooves at the splicing position. The reserved holes and grooves clamp the vicinity of the wave crest of the steel web member, and the steel web member is single-row.

[0011] Further, as a preference, the perforated and grooved cold-formed thin steel upper flange is composed of the splicing of "L-shaped" + "-shaped" + "L-shaped" cold-formed thin steel plates. The thin steel plates are provided with reserved holes and grooves at the splicing position. The reserved holes and grooves clamp the vicinity of the wave crest of the steel web member, and the steel web member is multi-row.

[0012] Further, preferably, the cold-formed thin steel upper flange with perforated grooves is a cold-formed channel steel with an upward opening, and holes are opened at the bottom of the channel steel, through which the wave crests of the steel web members pass.

[0013] Further, preferably, there are transverse short steels inside the cold-formed thin steel upper flange with perforated grooves.

[0014] Further, preferably, longitudinal ribs are arranged inside the ribs of the cold-formed thin steel upper flange with perforated grooves.

[0015] Further, preferably, the transverse short steels are located below the wave crests of the steel web members and above the longitudinal ribs inside the ribs.

[0016] Further, preferably, the longitudinal bottom bars and the longitudinal ribs inside the ribs are prestressed bars respectively.

[0017] Further, preferably, the steel web members are steel pipes or profiled steels.

[0018] Further, preferably, high-strength steel wires are threaded through the steel pipes and high-strength mortar is filled in.

[0019] Further, preferably, the steel web members are steel bars.

[0020] Further, preferably, the steel web members are composed of multiple continuously bent and folded wave shapes arranged in combination.

[0021] An implementation method of a cold-connected steel truss concrete composite slab, characterized in that it comprises the following steps:

[0022] The thin-walled steel strip is cut according to the size, punched and grooved according to the design, and then bent into an L shape;

[0023] Continuously bend the steel web members;

[0024] Place the steel web members in place, align the holes and grooves of the cold-formed profiled steel with perforated grooves with the steel web members, and then assemble them together;

[0025] Fix the cold-formed profiled steel with perforated grooves together by breaking point welding or riveting or self-tapping screws, etc.;

[0026] Clean the formwork table, apply the release agent, and fix the positions of the side formwork and the end formwork according to the component size;

[0027] Lay the longitudinal bottom bars and the longitudinal ribs inside the ribs of the cold-formed thin steel upper flange on the formwork table, and place the web member steel and the cold-formed thin steel upper flange steel;

[0028] Place the transverse short steels inside the cold-formed thin steel upper flange steel;

[0029] Complete the tensioning;

[0030] Pass the horizontal steel bars under the longitudinal steel bars in the ribs and above the troughs, and fix the channel steel trusses and horizontal steel bars;

[0031] Pour the concrete floor slab and the concrete inside the cold-formed thin steel upper flange of the perforated trough to make precast components;

[0032] Make precast components after the concrete reaches the required strength.

[0033] The utility model adopts the above technologies and has the following beneficial effects compared with the existing technologies: By utilizing the geometric relationship between the holes in the upper flange and the web members, a reliable cold connection between the steel web members and the upper flange is formed. Open holes are respectively made on the cold-formed thin steel of the upper flange at the positions where the web members pass through. The web members pass through the bottom of the thin flange, and the flange holes limit the sliding of the web members, forming a reliable mechanical connection. Through the relationship between the floor slab, longitudinal and transverse steel bars, the problem of unreliable connection of the composite truss joints is solved. The steel web members of the utility model are in a "Λ" shape, and the flange floor slab has holes in corresponding shapes at the corresponding positions of the two web members. The steel web members and the upper flange floor slab just fit. When the steel web members tend to move downward, the steel plates of the upper flange floor slab between the steel web members limit the displacement of the steel web members. When the web members tend to move upward, the steel plates of the upper flange floor slab outside the steel web members limit the displacement of the main beam steel web members. When there is horizontal sliding between the steel web members and the upper flange, the upper flange floor slab restricts the horizontal displacement between them. The concrete poured inside the upper flange fills the gap between the upper flange floor slab and the steel web members, and there is also an anchoring connection between the steel web members and the concrete. At the same time, by using cold-formed thin steel with the opening facing upward, the concrete in the upper flange and the floor slab can be poured together. The truss is light in weight and the component processing is simple. The whole process of truss production is cold bending and cold connection, and there is no welding process for the components, making the production more environmentally friendly and energy-saving, and more reliable than the traditional welded connection or bolt connection. Description of the Drawings

[0034] Figure 1 It is a form one of the connection between the upper flange of a cold-connected steel truss concrete composite slab and the steel web members;

[0035] Figure 2 It is a form two of the connection between the upper flange of a cold-connected steel truss concrete composite slab and the steel web members;

[0036] Figure 3 It is a form three of the connection between the upper flange of a cold-connected steel truss concrete composite slab and the steel web members;

[0037] Figure 4 It is a combined relationship diagram of the bottom slab steel bars of a cold-connected steel truss concrete composite slab and the truss;

[0038] Figure 5 It is a three-dimensional view of a cold-connected steel truss concrete composite slab.

[0039] In the figure: 1. Cold-bent thin steel upper flange with holes and grooves; 2. Steel web; 3. Concrete base plate; 4. Longitudinal steel bars at the bottom of the plate; 5. Transverse steel bars; 6. Post-cast concrete; 7. Transverse short steel bars; 8. Longitudinal steel bars inside the ribs. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0041] Example 1: Please refer to the attached Figures 1-5 The utility model provides a technical solution: including: a cold-bent thin steel upper flange with a hole groove, a steel web, and a concrete bottom plate. The cold-bent thin steel upper flange with a hole groove opens upward, and concrete is poured in the groove; the steel web is bent to form a continuous diagonal bar, the first diagonal bar and the second diagonal bar pass through the cold-bent thin steel upper flange with a hole groove respectively, intersect above the bottom plate of the cold-bent thin steel upper flange with a hole groove, form an angle of 20 to 80 degrees, and are anchored in the post-cast concrete; the second diagonal bar and the third diagonal bar intersect to form a 20 to 80 degree angle trough anchored in the concrete bottom plate; a bottom plate steel mesh composed of a plurality of bottom longitudinal steel bars and transverse steel bars is arranged in the concrete bottom plate, and part or all of the transverse steel bars pass through the trough and below the bottom longitudinal steel bars.

[0042] Furthermore, the upper flange of the cold-bent thin steel with holes and grooves is composed of two L-shaped cold-bent thin-walled steel pieces spliced ​​together, and the cold-bent thin-walled steel has holes and grooves reserved at the splicing position, and the reserved holes and grooves clamp the vicinity of the wave crest of the steel web, and the steel web is a single row. Figure 1 .

[0043] Further longitudinal reinforcement at the bottom of the slab and within the ribs are prestressed reinforcement.

[0044] Further steel web members are steel tubes or steel sections.

[0045] Furthermore, the steel tube steel web is penetrated with high-strength steel wire and filled with high-strength mortar. The high-strength steel wire increases the tensile strength of the web, and the high-strength mortar increases the compressive strength of the steel web and has a gripping effect on the high-strength steel wire.

[0046] Furthermore, the steel web is composed of multiple sections of continuous curved waves, which are arranged in combination.

[0047] Example 2: It is basically the same as Example 1, except that the perforated-groove cold-formed thin steel upper flange is composed of the splicing of "L-shaped" + "-shaped" + "L-shaped" cold-formed thin steel. Perforated grooves are reserved at the splicing of the thin steel, and the reserved perforated grooves clamp near the wave crest of the steel web member, and the steel web member is double-row. Refer to Figure 2

[0048] Furthermore, the steel web member is a steel bar.

[0049] Example 3: It is basically the same as Example 1, except that the perforated-groove cold-formed thin steel upper flange is a cold-formed channel steel with an upward opening, and holes are opened at the bottom of the channel steel, and the wave crest of the steel web member passes through the holes. Refer to Figure 3

[0050] Furthermore, there are transverse short steels inside the perforated-groove cold-formed thin steel upper flange.

[0051] An implementation method of a cold-connected steel truss concrete composite slab, characterized in that it includes the following steps:

[0052] The thin steel strip is cut according to the size, perforated and grooved according to the design, and then bent into an L shape;

[0053] Continuously bend the steel web member;

[0054] Place the steel web member in place, align the perforated groove of the cold-formed section steel with perforated grooves with the steel web member, and then assemble them together;

[0055] Fix the cold-formed section steel with perforated grooves at the break points together by welding or riveting or self-tapping screws, etc.;

[0056] Clean the formwork table, apply the release agent, and fix the positions of the side formwork and the end formwork according to the component size;

[0057] Lay the longitudinal steel bars and the longitudinal steel bars inside the perforated-groove cold-formed thin steel upper flange on the formwork table, and place the web member steel and the perforated-groove cold-formed thin steel upper flange steel;

[0058] Place the transverse short steel inside the perforated-groove cold-formed thin steel upper flange steel;

[0059] Complete the tensioning;

[0060] Pass the transverse steel bars under the longitudinal steel bars and above the wave troughs, and fix the channel steel truss and the transverse steel bars;

[0061] Pour the concrete bottom slab and the concrete inside the perforated-groove cold-formed thin steel upper flange steel to make a precast component;

[0062] Wait for the concrete to reach the strength and then make a precast component.

[0063] Although embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. A cold-connected steel truss concrete composite slab, characterized in that: The invention comprises: a cold-bent thin steel upper flange with a hole groove (1), a steel web (2), and a concrete bottom plate (3). The cold-bent thin steel upper flange with a hole groove (1) is opened upward, and concrete (6) is poured in the groove. The steel web (2) is bent to form a continuous diagonal bar. A first diagonal bar (21) and a second diagonal bar (22) respectively pass through the cold-bent thin steel upper flange with a hole groove (1), intersect above the bottom plate of the cold-bent thin steel upper flange with a hole groove (1), form an angle of 20 to 80 degrees, and are anchored in the poured concrete (6). The second diagonal bar (22) and the third diagonal bar (23) intersect to form a trough with an angle of 20 to 80 degrees, which is anchored in the concrete bottom plate (3). A bottom plate steel mesh composed of a plurality of bottom plate longitudinal steel bars (4) and transverse steel bars (5) is arranged in the concrete bottom plate (3). The transverse steel bars (5) partially or completely pass through the top of the trough and the bottom of the bottom plate longitudinal steel bars (4).

2. The cold-connected steel truss concrete composite slab according to claim 1, characterized in that: The cold-bent thin steel upper flange (1) with holes and grooves is formed by splicing two L-shaped (11) cold-bent thin-walled steel sheets. The cold-bent thin-walled steel has holes and grooves reserved at the splicing position. The reserved holes and grooves clamp the vicinity of the wave crest of the steel web (2). The steel web (2) is in a single row.

3. The cold-connected steel truss concrete composite slab according to claim 1, characterized in that: The cold-bent thin steel upper flange (1) with holes and grooves is composed of "L-shaped" (11) + "-shaped" (12) + "L-shaped" (11) cold-bent thin-walled steels spliced ​​together, and holes and grooves are reserved in the thin-walled steel at the splicing position. The reserved holes and grooves clamp the vicinity of the wave crest of the steel web (2), and the steel web (2) is arranged in multiple rows.

4. The cold-connected steel truss concrete composite slab according to claim 1, characterized in that: The cold-bent thin steel upper flange (1) with a hole groove is a cold-bent channel steel with an opening upward, a hole is formed at the bottom of the channel steel, and the wave crest of the steel web member (2) passes through the hole.

5. The cold-connected steel truss concrete composite slab according to claim 1, characterized in that: The cold-bent thin steel upper flange (1) with holes and grooves has a transverse short steel (7) inside.

6. The cold-connected steel truss concrete composite slab according to claim 1, characterized in that: Inner-rib longitudinal steel bars (8) are arranged in the cold-bent thin steel upper flange (1) with perforated grooves.

7. The cold-connected steel truss concrete composite slab according to claim 5, characterized in that: The transverse short steel (7) is located under the wave crest of the steel web member (2) and on the longitudinal steel bars (8) inside the rib.

8. The cold-connected steel truss concrete composite slab according to claim 1 or claim 6, characterized in that: The slab bottom longitudinal steel bars (4) and the rib inner longitudinal steel bars (8) are respectively prestressed steel bars.

9. The cold-connected steel truss concrete composite slab according to claim 1, characterized in that: The steel web member (2) is a steel pipe or a steel section.

10. The cold-connected steel truss concrete composite slab according to claim 9, characterized in that: The steel pipe is penetrated by high-strength steel wire and filled with high-strength mortar.

11. The cold-connected steel truss concrete composite slab according to claim 1, characterized in that: The steel web member (2) is a steel bar.

12. The cold-connected steel truss concrete composite slab according to claim 1, characterized in that: The steel web (2) is composed of multiple sections of continuously bent wave-shaped components, which are arranged in combination.

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