Lower string steel floor support plate and manufacturing method

Abstract

The invention relates to the technical field of engineering, discloses a lower string steel floor support plate and a manufacturing method, and aims at solving the problems that a traditional profiled steel sheet floor support plate is small in support-free span (smaller than or equal to 2.7 m), high in secondary beam density, tedious in field procedure and poor in structural collaboration. The core structure of the floor support plate comprises a profiled steel plate (comprising concave ribs and convex ribs which are alternately arranged, and side wall plates, a bottom plate and a top plate which are enclosed to form the concave ribs / convex ribs) which is integrally formed by cold bending, connecting fixing pieces, lower string longitudinal steel bars and anchoring pieces; and meanwhile, transverse tie steel can be arranged on the concave ribs, cold pressing ribs are arranged on the side wall plates, bending ribs are arranged on the bottom plate / top plate, an additional truss can be additionally arranged above the concave ribs / convex ribs, and a flat plate can be arranged below the profiled steel plate. The manufacturing method comprises the steps of steel plate rib pressing, roll bending forming, connecting piece fixing, truss assembling, steel bar tensioning and the like. The support-free span is increased to 4.0 m or above, the total steel consumption of the structure is reduced by 30%-40%, the field process is simplified, the structure collaboration and durability are enhanced, and the method is suitable for various engineering floors.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engineering, and particularly relates to a lower tension string steel floor support plate and a manufacturing method, which can be widely applied to floors of various projects. BACKGROUND

[0002] The profiled steel plate floor support plate is a core load-bearing and formwork integrated component of a steel structure building, and has been widely applied to various projects such as industrial plants, commercial complexes, multi-story parking garages and exhibition centers due to its advantages of convenient construction and outstanding economy. Compared with the traditional cast-in-place floor, the profiled steel plate floor support plate can shorten the construction period by 30%-40%, reduce the comprehensive cost by 10%-15%, reduce the amount of concrete by 20%-30%, and the steel amount thereof is usually only 15-25 kg / m2, which is one of the key technologies for realizing building energy saving and consumption reduction.

[0003] However, the profiled steel plate floor support plate in the prior art has the following technical defects which have not been properly solved for a long time and seriously restrict the performance improvement and engineering economy in actual application, which are known by those skilled in the art.

[0004] Limited free span and insufficient bearing capacity: limited by the conventional completion thickness of the floor (usually 100-150 mm), the effective height of the cross section (wave height) of the profiled steel plate is generally only 50-80 mm. At the same time, in order to ensure the self rigidity of the profiled steel plate as a formwork during the construction stage, the thickness of the bottom plate needs to be maintained at 0.8-1.2 mm. These two factors together cause the small cross-sectional moment of inertia, limited bending bearing capacity, and the profiled steel plate cannot bear large-span construction load. At present, the free span of most products on the market is generally ≤2.7 meters, which cannot meet the demand for a span of more than 4 meters in modern large-space buildings.

[0005] High secondary beam density and increased total steel amount: in order to match the free span of the floor support plate ≤2.7 meters, the spacing of the secondary beams must be controlled within the range. This leads to a large increase in the number of secondary beams, significantly increasing the total steel amount and cost of the structure. Taking a 1000 m2 floor as an example, the steel amount of the secondary beams in the traditional scheme can reach 80-100 kg / m2, which is increased by 30%-40% compared with the ideal large-span scheme (secondary beam spacing 4-5 meters). This not only increases the engineering cost, but also occupies valuable building internal headroom due to the excessive number of beams.

[0006] Complex on-site procedures and low construction efficiency: In the traditional floor support plate construction, in order to enhance the stress performance of the floor in the use stage, additional bottom stress reinforcement is still needed to be laid on site. Since the bottom reinforcement is not in direct contact with the body of the floor support plate, a large number of reinforcement protection layer pads (usually 6-8 per square meter) must be added to ensure its design position. This procedure not only increases the material cost (pad and auxiliary fixing cost about 5-8 yuan / square meter), but also prolongs the construction time (pad laying and reinforcement positioning need to consume additional time of 0.5-1 hour / square meter), which seriously affects the overall construction progress and offsets the efficiency advantage brought by part of the assembly construction.

[0007] Poor structural synergy and easy to produce local failure: The traditional profiled steel plate mainly bears the dual roles of "concrete pouring formwork" and "later tension reinforcement", and it cannot form an integrated and synergistic stress system with the bottom reinforcement and concrete laid later, so the carrying capacity improvement space is limited. In addition, the transition web (inclined section connecting concave rib and convex rib) of the profiled steel plate is prone to stress concentration under load due to unreasonable angle design (usually 90°-110°), which leads to premature web buckling deformation, and then causes local cracking or carrying capacity reduction of the floor, which has safety hazards.

[0008] In view of the above defects, although some improvement schemes have been proposed in the industry, they have not achieved a comprehensive breakthrough:

[0009] Conventional method one: increase the thickness of the bottom plate of the profiled steel plate (to 1.3-1.5 mm) to improve the stiffness, although it can slightly increase the support-free span to about 3.0 meters, but the steel consumption increases by 20%-50%, which directly offsets the economic advantage, and the fundamental problems of complex on-site procedures and poor structural synergy are not solved at all.

[0010] Conventional method two: add temporary support (such as full-dormant steel pipe frame) under the floor support plate to achieve a larger span (≤3.8 meters). However, this does not achieve true "support-free", and the erection and removal of temporary support greatly increases the construction measure cost (about 12-15 yuan / square meter) and construction period (20%-25% longer), and after the support is removed, the problem of insufficient structural synergy still exists.

[0011] In summary, the existing technology cannot meet the comprehensive needs of modern steel structure engineering for "low material consumption, high span, support-free, and few procedures". Therefore, there is an urgent need in the field for an innovative profiled steel plate floor support plate scheme that can fundamentally break through the limitation of support-free span, significantly reduce the steel consumption of secondary beams, greatly simplify the on-site procedures, and strengthen the overall structural synergy. SUMMARY

[0012] The present application aims to overcome the deficiencies of the prior art, and provide a lower string steel floor support plate and a manufacturing method thereof. The scheme effectively solves the four core pain points of small support-free span, high secondary beam density, multiple construction procedures and poor synergy by innovative structural design, which deeply integrates the lower string prestressed technology with the profiled steel sheet-concrete composite structure.

[0013] To achieve the above object, the present application adopts the following technical scheme:

[0014] A lower string steel floor support plate, characterized in that it comprises a profiled steel sheet, a connecting fixing part, a lower string longitudinal steel bar and an anchoring part; the profiled steel sheet has alternating concave ribs and convex ribs, and further comprises a side wall plate; the concave ribs are formed by the side wall plate and a bottom plate, and the convex ribs are formed by the side wall plate and a top plate; the bottom plate, the top plate, the side wall plate and the concave ribs and the convex ribs formed by them are integrally formed by a whole thin steel plate through a cold bending process, ensuring the integrity and continuity of the structure;

[0015] The connecting fixing part is fixedly connected with the bottom plate of the concave rib or the side wall plates on both sides of the concave rib, serving as a reliable force transmission medium of the string system;

[0016] The lower string steel bar has the dual core functions of "construction stage string member" and "use stage floor stress steel bar": first, before the concrete is poured, it is used as a string member to apply prestress by tensioning, offsetting the tensile stress generated by the construction load, and providing a mechanical basis for large-span support-free floor support plates; second, after the concrete hardens, it needs to directly serve as a stress steel bar of the floor, and cooperates with the concrete to bear the permanent load (such as floor self-weight and decoration load) and variable load (such as personnel and equipment load) during the building use period, replacing the traditional site-laid bottom stress steel bar, and greatly simplifying the construction procedure.

[0017] From the perspective of structural safety and durability, according to the requirements of Code for Design of Concrete Structures (GB 50010-2010), Code for Design of Building Fire Protection (GB 50016-2014, 2018 edition) and Code for Durability Design of Concrete Structures (GB / T 50476-2008), the floor reinforcing steel bars need to have sufficient concrete cover thickness: in terms of fire performance, a 15-30mm cover can make the floor fire resistance limit reach 1.5-2.0h, avoiding the rapid heat conduction of profiled steel sheet (Q355B profiled steel sheet thermal conductivity coefficient reaches 45W / (m·K)) under high temperature environment (such as fire), preventing the steel strength from falling below 10% of the normal temperature at 1000℃, and ensuring the structural fire safety; in terms of durability, this cover thickness can effectively isolate the contact between air, water vapor and steel, control the steel corrosion rate below 0.01mm / year, extend the steel corrosion life to more than 50 years, and meet the durability requirements of the main building structure.

[0018] Based on the above-mentioned cover thickness requirement, a 15-30mm spacing needs to be maintained between the bottom plate of the profiled steel sheet and the bottom plate of the profiled steel sheet, which cannot be directly attached to the profiled steel sheet - if forced to be attached (cover thickness <10mm), not only will it cause structural safety hazards due to insufficient fire and durability, but also will it cause the pre-stress in the construction stage to be unable to be transmitted to the profiled steel sheet, thereby losing the mechanical advantage of the cable-strut structure.

[0019] To solve the problem of "force transmission interruption caused by cover spacing", a special connecting fixture needs to be set: on the one hand, the fixture needs to be precisely supported by the lower cable-strut steel bar through the integrated positioning protrusion (height matching the cover thickness, 15-30mm), to ensure the stable spacing between the steel bar and the bottom plate of the profiled steel sheet, and to avoid the cover thickness deviation exceeding the ±3mm range specified in Code for Construction Quality Acceptance of Concrete Structures (GB 50204-2015); on the other hand, the fixture needs to be rigidly connected with the profiled steel sheet through welding or bolts (connection area ≥500mm², force transmission cross-sectional area ≥300mm²), to build a complete force transmission path of "lower cable-strut steel bar → connecting fixture → profiled steel sheet", to realize the effective transmission of pre-stress in the construction stage and load tension in the use stage, and finally to achieve the design goal of "considering both functions, meeting fire and durability standards, and continuous force flow transmission". The lower cable-strut longitudinal steel bar is fixedly connected with the connecting fixture through the anchor, to realize the indirect fixation of the lower cable-strut longitudinal steel bar and the profiled steel sheet, and to apply pre-stress to the lower cable-strut longitudinal steel bar, forming an efficient self-balancing structure system of the lower cable-strut, and establishing a beneficial pre-stress field in the plate.

[0020] Preferably, the upper or middle part of the two side walls of the concave rib is provided with transverse tie steel, effectively limiting the relative displacement of the side walls, enhancing the anti-deformation ability and cross-section stability of the concave rib.

[0021] During the concrete pouring process, the left and right side walls of the concave rib will be subjected to lateral pressure of the concrete, resulting in outward expansion deformation. If the upper edge of the side wall is not constrained by the tie, it will form an unfavorable boundary condition with the upper edge free and the lower edge fixed, significantly increasing the lateral deformation. Especially when the concave rib depth is large, it is still difficult to effectively control the deformation by fixing the upper and lower edges of the side wall. Compared with the high-cost solution of simply increasing the thickness of the steel plate, adding transverse tie steel in the middle or upper part of the side wall can provide intermediate constraint in a more economical and efficient way, significantly enhancing the anti-deformation ability and overall stability of the side wall, effectively suppressing the lateral deformation during the concrete pouring process. Thus, the mechanical properties of the profiled steel plate and the performance of the same truss combination are ensured.

[0022] Preferably, the two side walls are provided with cold-pressed ribs, which are vertical, diagonal, or eight-shaped or cross-shaped, greatly improving the local stability, buckling load and overall out-of-plane stiffness of the side wall through cold work hardening effect and geometric stiffening effect. The eight-shaped or cross-shaped shape conforms to the force transmission route, and further improves the carrying capacity of the side plate.

[0023] Preferably, the bottom plate or top plate is provided with longitudinal bending ribs as stiffening ribs to improve the local stability of the plate and enhance the gripping and combination effect with the concrete.

[0024] Preferably, the top plate is provided with transverse cold-pressed ribs to further improve the stiffness and anti-deformation ability of the top plate.

[0025] Preferably, the width of the bottom plate is less than the width of the top plate, which helps to optimize the force flow transmission in the concrete slab, making the pressure more effectively spread to the support area. Reducing the amount of concrete poured, reducing the self-weight of the structure and improving the load-bearing capacity of the floor slab, reducing the amount of steel used.

[0026] Preferably, an additional truss is provided above the concave rib or convex rib, and the space truss structure can greatly improve the stiffness and bending capacity of the floor slab during the concrete pouring construction stage, thereby realizing a larger free support span.

[0027] Preferably, the additional truss is composed of a top chord and a single row or multiple rows of web members, forming an efficient truss force transmission mechanism.

[0028] Preferably, the web members are continuously bent into a wave shape by steel bars or steel pipes, and the top chord is various section steel; the wave crest of the web member is fixedly connected with the top chord, and the wave trough is fixedly connected with the profiled steel plate, effectively transmitting the truss shear force to the profiled steel plate to form a space composite structure.

[0029] Preferably, the trough of the web plate is fixedly connected to the top plate, and is located close to the side wall plate, so as to directly transmit the truss force to the profiled steel sheet, and the rigidity is greater, the stress is more optimal, and the spatial structure is more stable.

[0030] Preferably, the trough of the web plate is fixedly connected to the side wall plate. The lower edge of the side wall plate is connected to the bottom plate, so as to form a pair of tension-compression combined spatial structures of the upper flange of the truss and the concave rib bottom plate, the shear effect of the web plate and the side wall plate is fully utilized, the torque of the tension-compression section is increased, and the bending resistance of the spatial rib is improved.

[0031] Preferably, the trough of the web plate is fixedly connected to the bottom plate. When the side wall plate is thin and the floor slab has a large span, the shear resistance of the side wall plate cannot bear the load, and the web plate is directly connected to the bottom plate. Meanwhile, the tensioning chord steel bars can be fixed at a position close to the trough by means of the web plate, and the utility of the connecting and fixing members is reduced.

[0032] Preferably, the connecting and fixing member is a flat steel, a channel steel, a steel pipe, a steel bar or a trough part of the web plate of the additional truss, so as to realize function integration and material saving.

[0033] Preferably, the anchoring member is a nut, a prestressed anchorage device or a weld, and reliable prestress anchoring is provided.

[0034] Preferably, a flat plate is connected below the profiled steel sheet, and the flat plate is a gypsum board, a cement calcium plate or a fiber cement plate, so as to avoid suspended ceilings, realize the unification of the flat and beautiful bottom surface of the building, fire prevention, sound insulation and other functions, improve the construction efficiency on site, and protect the floor slab from direct contact with air, so as to improve the fireproof and durable performance of the floor slab.

[0035] A manufacturing method of the lower tension chord steel floor slab, and the method comprises the following steps:

[0036] Step 1: horizontal ribs, inclined ribs or cold-pressed ribs required by design are pre-pressed on the steel plate by rolling or stamping process;

[0037] Step 2: a roll bending machine group is used to continuously bend the steel plate with the pressed ribs, so as to form a profiled steel plate with a specific cross-sectional shape, and the profiled steel plate comprises designed concave ribs and convex ribs;

[0038] Step 3: transverse tie steel bars and connecting and fixing members are welded or riveted and fixed in the concave ribs;

[0039] Step 4: a special bending device is used to continuously bend the steel bars or steel pipes to form web plates with a designed wave shape;

[0040] Step 5: the upper chord is fixedly connected to the wave crest of the web plate by welding or mechanical connection, and an additional truss is assembled.

[0041] Step 6: weld the web valley of the additional truss to the roof slab, side wall slab or floor slab of the profiled steel sheet;

[0042] Step 7: install the lower cable longitudinal reinforcement, pass it through or connect it to the connecting fixture, and preliminarily fix its two ends to the connecting fixture through the anchor (such as a nut);

[0043] Step 8: tighten the nut or tension the anchor device using a torque wrench or tensioning equipment to form the initial prestress of the lower cable longitudinal reinforcement according to the design;

[0044] Step 9: install the prefabricated flat plate below the profiled steel sheet through self-tapping screws or adhesives to complete the integrated ceiling function.

[0045] The beneficial effects of the present application are:

[0046] ①Greatly improve the unsupported span and bearing capacity: By applying prestress through the "lower cable longitudinal reinforcement", a pre-compressive stress is established in the floor slab, which significantly offsets the tensile stress caused by the wet weight of concrete and live load during construction. The unsupported span can be increased from the traditional 2.7 meters to more than 4.0 meters. Combined with the composite truss effect of the "additional truss" and the enhancement of the stability of the plate by various reinforcing ribs (cold-pressed ribs, bent ribs), the cross-sectional stiffness and bearing capacity are fundamentally enhanced.

[0047] ②Significantly reduce the total steel consumption and comprehensive cost of the structure: The increase of the unsupported span allows the spacing between secondary beams to be increased to 4 meters or more, reducing the number of secondary beams by 30%-40% and their steel consumption, manufacturing and installation costs. Although the steel consumption of the floor slab itself increases slightly due to the enhancement measures, the total steel consumption and comprehensive cost of the structure are significantly reduced, and the economic benefits are obvious.

[0048] Completely simplify the site construction process and improve efficiency: The "lower cable longitudinal reinforcement" and "additional truss" are integrated and pre-assembled with the profiled steel sheet in the factory, completely replacing the cumbersome procedures of laying force-bearing steel bars, distributing steel bars and installing cushion blocks on site, saving a large amount of labor and time, and improving construction efficiency by more than 20%, and reducing the quality and safety risks of on-site operations.

[0049] ③Excellent structural synergy and safety: The lower cable longitudinal reinforcement, additional truss and profiled steel sheet form a firm whole through the connecting fixture and anchor, and work together with the post-cast concrete to form a highly integrated and synergistic stress system. The system has a clear force transmission path and uniform stress distribution, avoiding the risk of premature buckling of the profiled steel plate web in traditional composite floors, and significantly improving the safety, reliability and durability of the structure.

[0050] ④ Function integration and architectural aesthetics: By integrating the lower slab in the factory, the integration of floor slab and ceiling is realized, the process of site ceiling is saved, the cost is saved, the flatness and aesthetics of the building bottom are ensured, and the integrated lighting, pipeline and other facilities are facilitated.

[0051] Working principle: The core principle of the floor slab is to comprehensively utilize the lower chord technology, the combination effect and the truss effect. In the construction stage, the system is subjected to a reverse load by the tensioned lower chord longitudinal steel, which offsets part of the positive bending moment; the additional truss provides great short-term stiffness and bearing capacity, which jointly ensures the construction safety under large span. In the use stage, the prestressed tendon and the concrete are bonded to jointly bear the load, and continue to provide bending resistance; after the concrete hardens, the profiled steel plate and the upper chord of the truss form a composite section, which jointly bears the use load and shows excellent overall working performance. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application Figure 1 (without truss).

[0053] Figure 2 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application Figure 2 (without truss, with decorative slab).

[0054] Figure 3 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application Figure 3 (without truss, with decorative slab).

[0055] Figure 4 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application Figure 1 .

[0056] Figure 5 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application Figure 2 .

[0057] Figure 6 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application Figure 3 .

[0058] Figure 7 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application Figure 4 .

[0059] Figure 8 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application Figure 5 .

[0060] Figure 9 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application

[0061] Figure 10 is a three-dimensional schematic diagram of the lower chord steel floor slab of the present application

[0062] Figure 11 The three-dimensional schematic diagram of the string steel floor support plate with truss under the invention Figure 1 .

[0063] Figure 12 The three-dimensional schematic diagram of the string steel floor support plate with truss under the invention Figure 2 .

[0064] Figure 13 The three-dimensional schematic diagram of the string steel floor support plate with truss under the invention Figure 3 .

[0065] Figure 14 The three-dimensional schematic diagram of the string steel floor support plate with truss under the invention Figure 4 .

[0066] Figure 15 The numbering diagram of each bending part of the profiled steel plate.

[0067] Figure 16 The numbering diagram of each bending part of the profiled steel plate.

[0068] Figure 17 The typical example of the connection position of the additional truss and the profiled steel plate.

[0069] (Fig. 1: profiled steel plate; 2: connecting fixing part; 3: lower string longitudinal steel bar; 4: anchoring part; 5: concave rib; 6: convex rib; 7: side wall plate; 8: bottom plate; 9: top plate; 10: transverse tie steel; 11: cold-pressed rib; 12: longitudinal bending rib; 12a: transverse cold-pressed rib; 13: additional truss; 14: upper chord; 15: web; 16: flat plate; 17: transverse short steel) DETAILED DESCRIPTION

[0070] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0071] Embodiment 1:

[0072] As shown in the accompanying drawings Figure 1As shown, a kind of lower string steel floor support plate, including by a whole thin steel plate cold bending forming profiled steel sheet (1).The profiled steel sheet (1) has the concave rib (5) and convex rib (6) of alternate arrangement.The concave rib (5) is enclosed by the side wall plate (7) and bottom plate (8) of two sides;The convex rib (6) is enclosed by the side wall plate (7) and top plate (9) of two sides.In the bottom plate (8) of concave rib (5) central welding has as connecting fixing piece (2) channel steel.Lower string longitudinal reinforcement (3) (usually high-strength prestressed threaded steel bar) passes through the channel steel, and two ends are anchored by the nut as anchoring piece (4) and prestressed.The lower string longitudinal reinforcement (3) is tensioned by screwing the nut, to establish effective pre-stress in floor support plate system, greatly improve its rigidity and support-free span in construction phase.

[0073] Example 2:

[0074] On the basis of example 1, as shown in the attached Figure 2 And 3 As shown, transverse tie steel (10) is arranged above the side wall plate (7) of the concave rib (5) on both sides;The deformation of the concave rib can be limited, and the thickness of the profiled steel sheet can be reduced.The cement fiber board (16) is arranged below the profiled steel sheet (1).That is, as a decorative effect, it also serves as protection for the profiled steel sheet against fire and durability.

[0075] Example 3:

[0076] On the basis of examples 1 and 2, as shown in the attached Figure 11 Additional truss (13) is added above the concave rib (5).The additional truss (13) is composed of a channel steel with an opening downward as top chord (14) and web member (15) which is continuously bent into a wave shape from steel bar.The wave crest of web member (15) is welded to the top chord (14), and the wave trough is welded to the top plate (9) of convex rib (6), very close to the position of side wall plate (7), to optimize force transmission.The additional truss (13) works with the lower string longitudinal reinforcement (3) to greatly increase the support-free span.In order to further enhance the stability of the concave rib (5), cold-pressed ribs (11) in the shape of a splayed are arranged in the middle of the side wall plate (7) on both sides

[0077] Example 4:

[0078] On the basis of example 3, as shown in the attached Figure 12 As shown, transverse short reinforcement (17) is arranged at the wave trough of web member (15) of additional truss (13), and the top chord of additional truss (13) is arranged as a flat tube.The position of web member (15) connecting with profiled steel sheet (1) is at the intersection of top plate (9) and (7), and a chamfer is arranged at the intersection.

[0079] The manufacturing method of the lower tension string steel floor support plate comprises the following steps: firstly, all the cold-pressed ribs and bent ribs required by design are pressed on the steel plate through rolling process; then the steel plate is continuously bent into the final profiled steel plate (1) section through a bending machine group; then the connecting fixing member (2) and the transverse tie steel (10) are installed and welded in the concave rib (5); then the web member (15) is bent by using special equipment and welded with the upper chord (14) into a truss, and the wave trough of the web member (15) of the truss is welded with the predetermined position of the profiled steel plate (1); then the lower tension string longitudinal steel bars (3) are installed and preliminarily fixed by using nuts; before leaving the factory, all the nuts are uniformly tightened by using a special torque wrench, and the initial prestress of the steel bars is applied; finally, the flat plate (16) for integrated ceiling is installed, and the product can be packed and transported to the construction site for use.

[0080] The above merely describes the preferred embodiments of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacements or changes to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, and all of the above should be covered within the protection scope of the present application.

Claims

1. A downstringed steel floor deck characterized by, The profiled steel sheet (1), the connecting fixing part (2), the lower tension string longitudinal steel bar (3) and the anchoring part (4); The profiled steel sheet (1) has alternating concave ribs (5) and convex ribs (6), and the profiled steel sheet (1) further comprises side wall plates (7); wherein the concave ribs (5) are formed by the side wall plates (7) and bottom plates (8), the convex ribs (6) are formed by the side wall plates (7) and top plates (9), and the bottom plates (8), the top plates (9), the side wall plates (7) and the concave ribs (5) and the convex ribs (6) formed by them are integrally formed by bending an integral thin steel sheet; The connecting fixing part (2) is fixedly connected with the bottom plate (8) of the concave rib (5), or is fixedly connected with the side wall plates (7) on both sides of the concave rib (5); The lower tension string longitudinal steel bar (3) is fixedly connected with the connecting fixing part (2) through the anchoring part (4), so as to indirectly fix the lower tension string longitudinal steel bar (3) and the profiled steel sheet (1).

2. The lower string steel deck of claim 1, wherein: The upper part or the middle part between the side wall plates (7) on both sides of the concave rib (5) is provided with a transverse tie steel (10).

3. The lower string steel deck of claim 1, wherein: The two side wall plates (7) are provided with cold-pressed ribs (11), which are vertical or inclined or eight-shaped or cross-shaped.

4. The lower catenary steel deck of claim 1, wherein: The bottom plate (8) or the top plate (9) is provided with a longitudinal bending rib (12).

5. The lower catenary steel deck of claim 1, wherein: The top plate (9) is provided with a transverse cold-pressed rib (12a).

6. The lower catenary steel deck of claim 1, wherein: The width of the bottom plate (8) is smaller than the width of the top plate (9).

7. The lower catenary steel deck of claim 1, wherein: An additional truss (13) is arranged above the concave rib (5) or the convex rib (6).

8. The lower string steel deck of claim 7, wherein: The additional truss (13) is composed of a top chord (14) and a single-row or multi-row web member (15).

9. The lower catenary steel deck of claim 8, wherein: The web member (15) is continuously bent into a wave shape with alternating wave crests and wave troughs by a steel bar or a steel pipe or a flat tube or a channel steel or a flat steel; the top chord (14) is an upward-opening channel section or a downward-opening channel section or an elliptical steel pipe or a rectangular steel pipe or a flat steel or a trapezoidal pipe; the wave crest of the web member (15) is fixedly connected with the top chord (14), and the wave trough is fixedly connected with the profiled steel sheet (1).

10. The downstringed steel deck panel of claim 9, wherein: The wave trough of the multi-row web member (15) is connected with a transverse short steel (17).

11. The downstringed steel deck panel of claim 9, wherein: The wave trough of the web member (15) is fixedly connected with the top plate (9) and is located close to the side wall plate (7).

12. The downstringed steel deck panel of claim 9, wherein: The wave trough of the web member (15) is fixedly connected with the side wall plate (7).

13. The downstringed steel deck panel of claim 9, wherein: The wave trough of the web member (15) is fixedly connected with the bottom plate (8).

14. The lower catenary steel deck of claim 1, wherein: The connecting fixing part (2) is a flat steel or a channel steel or a steel pipe or a steel bar or a wave trough of the web member (15) of the additional truss (13).

15. The lower catenary steel deck of claim 1, wherein: The anchoring part (4) is a nut or a prestressed anchorage device or a weld.

16. The lower catenary steel deck of claim 1, wherein: A flat plate (16) is connected below the profiled steel sheet (1).

17. The downstringed steel deck panel of claim 16, wherein: The flat plate (16) is a gypsum board or a cement calcium board or a fiber cement board.

18. A method of manufacturing a bottom chord steel deck panel, the method comprising: The method comprises the following steps: Step 1: pressing horizontal and diagonal ribs on the steel plate; Step 2: using a roll bending machine to bend the steel plate to form a profiled steel plate (1) with concave ribs (5) and convex ribs (6); Step 3: fixing horizontal tie steel (10) and connecting fixing member (2) in the concave ribs (5); Step 4: bending to form web member (15); Step 5: connecting the top chord (14) with the web member (15) to form an additional truss (13); Step 6: welding the web member (15) of the additional truss (13) to the structure near the concave ribs (5) or convex ribs (6); Step 7: installing the lower chord longitudinal steel bar (3) and fixing it with the connecting fixing member (2) through the anchor (4); Step 8: tightening the nut to form the initial stress; Step 9: fixing the flat plate (16) under the profiled steel plate (1).

Images