A formwork support structure and construction method for large-spacing steel beams

Abstract

The invention discloses a formwork frame structure and construction method on a large-spacing steel beam, including a steel beam platform as an operating platform and a formwork frame erected on the steel beam platform, the formwork frame including a safety net and a plurality of scaffolding boards, a steel pipe upright pole 1, a steel pipe upright pole 2, a steel pipe circumferential horizontal rod, and a steel pipe radial horizontal rod, the safety net is fully hung on the corresponding steel beam constituting the steel beam platform, and the top of the steel beam is fully covered with scaffolding boards; the steel pipe upright pole 1 is arranged perpendicular to the upper surface of the steel beam and installed on the steel beam, the steel pipe upright pole 2 is arranged perpendicular to the upper surface of the scaffolding board and is suspended without support; the steel pipe upright pole 1 or the steel pipe upright pole 2 are connected to the corresponding steel pipe circumferential horizontal rod and the steel pipe radial horizontal rod to form a whole. Compared with the prior art, the formwork frame in the invention has the upright poles suspended between the steel beams, which saves materials, does not require welding, simplifies the types of work, reduces labor and material costs, is conducive to material turnover, is convenient for inspection during use and removal after use, and shortens the construction period.

Description

Technical Field

[0001] The present invention relates to the field of construction engineering, and more specifically, to a formwork support structure on large-spacing steel beams and a construction method thereof. Background Art

[0002] At the construction site, in order to ensure the safety and smooth progress of construction operations, when constructing the upper floor slab of a small opening indoors or the top slab of a shallow silo dozens of meters high, high-formwork steel beam platforms are usually used to support the formwork support for the shallow silo. In addition to ensuring sufficient strength, stiffness, and stability, this formwork support also needs to consider economic practicality. Reinforced concrete silos are widely used in a large number of high-standard granaries to be constructed. There are a large number of high-formwork operations during the construction of the granary roof slab. The technology of erecting a full hall scaffold on a standardized and reusable steel beam platform is commonly used. In recent years, the real estate market has been sluggish, and many construction enterprises have entered the infrastructure field, resulting in fierce competition. On the premise of ensuring safety and quality, reasonably reducing costs will greatly enhance the competitiveness and voice of enterprises.

[0003] In the construction of concrete main structures, it is relatively common to erect a full hall scaffold on a formwork steel platform and on a large-span opening. If the spacing of the steel beams meets the spacing of the full hall scaffold vertical poles, the number of steel beams will increase, and the measure cost will increase significantly, resulting in poor economy. Therefore, the design of the steel platform determines the cross-section and spacing of the steel beams according to the surface load on the upper full hall scaffold, resulting in most of the steel beam spacings exceeding the calculated spacing of the full hall scaffold vertical poles. The usual method is to set steel secondary beams across the opening or steel beams, and the vertical poles are located on the top surface of the steel secondary beam 17, as Figure 1 shown. This method is widely used when the number of openings is small due to the low total cost. However, in the construction of the top slab of a shallow silo, because the required length specifications of the steel secondary beams are numerous and the total quantity is large, if adopted, the economy is poor, the material cost and labor cost are too high, the construction period is long, and the material turnover rate is low. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to overcome the deficiencies such as excessive measure costs, long erection periods, and unfavorable material turnover caused by using profiled steel secondary beams when erecting a full hall scaffold on a formwork steel beam platform and on a large-span opening, and to provide a formwork support structure on large-spacing steel beams and a construction method thereof to reduce measure costs and shorten the construction period.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A formwork frame structure on large-spacing steel beams, comprising a steel beam platform as an operating platform and a formwork frame erected on the steel beam platform, the formwork frame comprising a safety net and a plurality of scaffolding boards, a first steel pipe upright, a second steel pipe upright, a steel pipe circumferential horizontal rod, and a steel pipe radial horizontal rod, the safety net is fully hung on the corresponding steel beams constituting the steel beam platform, and at the same time, the top of the steel beam is fully covered with scaffolding boards; the first steel pipe upright is arranged perpendicular to the upper surface of the steel beam and installed on the steel beam, the second steel pipe upright is arranged perpendicular to the upper surface of the scaffolding board and is suspended without support; the first steel pipe upright or the second steel pipe upright is connected to the corresponding steel pipe circumferential horizontal rod, The steel pipe radial horizontal bars are connected into a whole; three steel pipe circumferential horizontal bars are arranged vertically, and the lower circumferential horizontal bars, the middle circumferential horizontal bars, and the upper circumferential horizontal bars are arranged from bottom to top in sequence; multiple steel pipe circumferential horizontal bars on the same layer are arranged along the axial direction of the steel beam; the steel pipe radial horizontal bars cooperate with the steel pipe circumferential horizontal bars to arrange the lower radial horizontal bars, the middle radial horizontal bars, and the upper radial horizontal bars in sequence from bottom to top; the formwork frame between every two adjacent steel beams is a frame, and the two adjacent frames share one steel pipe vertical bar on the steel beam, and multiple frames are arranged to form a large-spacing steel beam upper formwork frame structure in the shape of an entire circle.

[0007] By adopting the formwork frame structure on large-spacing steel beams described in the present invention, the formwork frame body is erected in the steel beam area to support the upper structure. Compared with the prior art in which steel secondary beams are erected on the lower truss beams of the formwork frame, the formwork frame is suspended between the steel beams, which saves materials, does not require welding, streamlines the types of work, reduces labor and material costs, is beneficial to material turnover, is easy to inspect during use and dismantle after use, and shortens the construction period.

[0008] Preferably, the three vertically arranged steel pipe ring-shaped horizontal bars are arranged at the same spacing.

[0009] Preferably, the tops of the first steel tube upright pole and the second steel tube upright pole both protrude from the upper annular horizontal rod and the upper radial horizontal rod.

[0010] Preferably, as an upper formwork structure for shallow silo roof construction, its lower radial horizontal rods are sweeping rods, the middle radial horizontal rods are horizontal rods, and the upper radial horizontal rods are inclined rods.

[0011] Preferably, the formwork frame is a steel tube fastener-type full-floor scaffolding, and the intersections of the steel tube upright pole one or the steel tube upright pole two and the steel tube annular horizontal pole and the steel tube radial horizontal pole are interconnected by right-angle fasteners.

[0012] Preferably, as an upper formwork structure for shallow circular silo roof construction, there are 36 frames in total, two adjacent frames share a steel pipe upright on the steel beam, and the circumferential horizontal bars are disconnected at the steel beam and then connected to the steel pipe upright, and the circumferential horizontal bars are 36 broken lines surrounding a circle.

[0013] Preferably, when the spacing between the steel beams is greater than 1.2 m, four vertical poles are arranged along the circumference for each frame body, and two vertical poles in the middle of the span are suspended; when the spacing between the steel beams is not greater than 1.2 m, three vertical poles are arranged along the circumference, and one vertical pole in the middle of the span is suspended.

[0014] A construction method for a formwork support structure on large-spacing steel beams includes using a formwork support structure on large-spacing steel beams as described above, and the construction method includes the following steps:

[0015] a. Before hoisting, mark the landing positions of the first steel pipe vertical poles on the steel beams, and weld short steel bar heads for positioning the first steel pipe vertical poles.

[0016] b. Fully hang safety nets on the steel beams.

[0017] c. Lay scaffolding boards on the steel beams, leaving the landing positions of the first steel pipe vertical poles.

[0018] d. Erect the first steel pipe vertical poles on the upper surface of the steel beams; the first steel pipe vertical poles are sleeved on the short steel bar heads, arranged perpendicular to the upper surface of the steel beams, and connected to the circumferential horizontal bars and radial horizontal bars to form a whole; three circumferential horizontal bars are arranged vertically, and the lower circumferential horizontal bar, the middle circumferential horizontal bar, and the upper circumferential horizontal bar are arranged in sequence from bottom to top; the radial horizontal bars are arranged in sequence from bottom to top, including the lower radial horizontal bar, the middle radial horizontal bar, and the upper radial horizontal bar, in cooperation with the circumferential steel pipe horizontal bars.

[0019] e. Erect the second steel pipe vertical poles above the scaffolding boards. The second steel pipe vertical poles are arranged perpendicular to the upper surface of the scaffolding boards, erected in a suspended manner, and at the same time connected to the circumferential horizontal bars and radial horizontal bars to form a whole formwork support.

[0020] Preferably, the landing spacing positions of the first steel pipe vertical poles, the second steel pipe vertical poles, the spacing of the circumferential steel pipe horizontal bars, and the spacing of the radial steel pipe horizontal bars are all determined through simulation calculations using Midas software.

[0021] In summary, compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. By adopting the formwork support structure and construction method for large-spacing steel beams of the present invention, the formwork support frame body is erected on the steel beams, and the horizontal bars across the steel beams are encrypted, with the vertical poles between the steel beams suspended to support the upper structure. At this time, compared with the prior art of erecting secondary steel beams on the truss beams under the formwork support, the vertical poles between the steel beams of this formwork support are suspended, saving steel materials, eliminating steel production operations such as welding and cutting, reducing the number of work types, greatly reducing labor and material costs, and the steel pipe fastener materials are easier to turnover than the steel beams of different lengths, facilitating inspection during use and demolition after use, and shortening the construction period of the erection and demolition of the frame body.

[0023] 2. By adopting the formwork support structure and construction method on large-spacing steel beams of the present invention, a safety catch net is fully hung on the steel beams, which can prevent workers from falling accidentally and materials from dropping.

[0024] 3. By adopting the formwork support structure and construction method on large-spacing steel beams of the present invention, the steel beams are fully covered with scaffold boards, which is convenient for workers to walk, transfer materials and carry out construction operations above them. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0026] Figure 1 It is a schematic diagram of erecting a secondary steel beam on the truss beam at the lower part of the formwork support in the prior art.

[0027] Figure 2 It is a schematic plan view of the formwork support structure on large-spacing steel beams of the present invention.

[0028] Figure 3 It is an installation schematic diagram of the present invention.

[0029] Figure 4 It is Figure 3 The enlarged schematic radial cross-section view of the present invention shown within the dashed box in

[0030] Figure 5 It is an enlarged schematic plan view of a single bay of the formwork support on a steel beam of the present invention.

[0031] Figure 6 It is a schematic circumferential cross-section view of the formwork support on a steel beam of the present invention Figure 1 .

[0032] Figure 7 It is a schematic circumferential cross-section view of the formwork support on a steel beam of the present invention Figure 2 .

[0033] Figure 8 It is a model diagram of the formwork support for the conical surface of the silo roof slab.

[0034] Figures 9 - 13 It is a diagram of different simulation results.

[0035] In the figure: 1 - safety net, 2 - scaffolding board, 3 - steel pipe vertical pole 1, 4 - steel pipe vertical pole 2, 5 - steel pipe circumferential horizontal bar, 6 - steel pipe radial horizontal bar, 7 - steel beam, 8 - right-angle fastener, 9 - already-poured concrete wall, 10 - concrete wall to be poured, 11 - lower circumferential horizontal bar, 12 - middle circumferential horizontal bar, 13 - upper circumferential horizontal bar, 14 - lower radial horizontal bar, 15 - middle radial horizontal bar, 16 - upper radial horizontal bar, 17 - secondary steel beam. Specific implementation manner

[0036] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention, and should not be construed as a limitation to the present invention.

[0037] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0038] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more, unless otherwise specifically defined.

[0039] The present invention discloses a formwork support structure on large-spacing steel beams and its construction method. This structure uses a steel beam platform as an operating platform for the high formwork of the shallow silo roof slab, and a formwork support is erected on the steel beam. This formwork support is a full hall scaffold of fastener-type steel pipes. The full hall scaffold is placed on the large-spacing steel beams, and the supporting secondary steel beam of the middle vertical pole is cancelled by the way of encrypting the spacing of the horizontal bars across the steel beams. This construction method fully covers the wooden springboards on the large-spacing steel beams as the operating surface, directly erects the vertical poles of the full hall scaffold on the steel beams, the vertical poles between the large-spacing steel beams are suspended, and the spacing of the horizontal bars is encrypted to three rows. The radial inclined bars are arranged at the top with the same inclination angle as the inclined roof, and the rest of the horizontal bars are erected normally.

[0040] The structural system has stable stress, low construction cost and accelerated construction progress. Due to the elimination of secondary steel beams, this construction method can speed up the erection of formwork, speed up construction progress, reduce steel usage, reduce construction costs, speed up the dismantling of the frame and the turnover of all materials, reduce construction work types, and reduce management costs.

[0041] like Figures 2 - 7 As shown, the present invention provides a large-spacing steel beam formwork structure, comprising a steel beam platform as an operating platform and a formwork frame erected on the steel beam platform. The formwork frame support is erected on the upper surface of the steel beam 7 and connected into a whole by steel pipes.

[0042] Specifically, the formwork frame includes a safety net 1 and a plurality of scaffolding boards 2, a steel pipe upright pole 1 3, a steel pipe upright pole 2 4, a steel pipe circumferential horizontal rod 5, and a steel pipe radial horizontal rod 6. The safety net 1 is fully hung on the corresponding steel beams 7 that constitute the steel beam platform. At the same time, the top of the steel beam 7 is fully covered with scaffolding boards 2 to facilitate workers to walk, transfer materials and carry out construction work on it.

[0043] The steel pipe uprights and the steel pipe radial horizontal bars are connected to form a whole along the radial direction of the steel beam with the circumferential steel pipe. Specifically, the steel pipe upright 1 3 is arranged perpendicular to the upper surface of the steel beam 7, the steel pipe upright 2 4 is arranged perpendicular to the upper surface of the scaffolding board 2, the steel pipe upright 1 3 is installed on the steel beam 7, and the steel pipe upright 2 4 is suspended without support; the steel pipe upright 1 3 or the steel pipe upright 2 4 are connected to form a whole with the corresponding steel pipe circumferential horizontal bars 5 and the steel pipe radial horizontal bars 6; the steel pipe circumferential horizontal bars 5 are vertically arranged in three rows, and the lower circumferential horizontal bars 11, the middle circumferential horizontal bars 12, and the upper circumferential horizontal bars 13 are arranged in sequence from bottom to top; multiple steel pipe circumferential horizontal bars 5 on the same layer are arranged along the axial direction of the steel beam 7; the steel pipe radial horizontal bars 6 cooperate with the steel pipe circumferential horizontal bars 5 to arrange the lower radial horizontal bars 14, the middle radial horizontal bars 15, and the upper radial horizontal bars 16 in sequence from bottom to top.

[0044] The formwork frame between each two adjacent steel beams 7 is used as one frame, and the adjacent two frame bodies share a steel pipe upright pole 3 on the steel beam 7, and multiple frame bodies are arranged to form a large-spacing steel beam upper formwork frame structure in the shape of a whole circle.

[0045] In the above description, the three vertically arranged steel pipe annular horizontal bars 5 are arranged at the same spacing.

[0046] Furthermore, the tops of the steel pipe upright pole 1 3 and the steel pipe upright pole 2 4 protrude 1650 mm from the upper annular horizontal rod 13 and the upper radial horizontal rod, which facilitates the positioning of the steel pipe upright poles and prevents them from sliding down the slope.

[0047] Furthermore, in a specific embodiment, as an upper formwork structure for shallow silo roof construction, the lower radial horizontal rod 14 is a sweeping rod, the middle radial horizontal rod 15 is a horizontal rod, and the upper radial horizontal rod 16 is an inclined rod. The lower radial horizontal rod 14 and the middle radial horizontal rod 15 are encrypted horizontal rods. After comparative calculation by Midas software, the results show that the deflection and bending moment of the horizontal rod caused by the suspension of the mid-span vertical rod can be reduced.

[0048] Furthermore, the formwork frame is a steel pipe fastener type full-floor scaffolding, and the intersection of the steel pipe upright pole 1 3 or the steel pipe upright pole 2 4 and the steel pipe annular horizontal pole 5 and the steel pipe radial horizontal pole 6 is interconnected by a right-angle fastener 8.

[0049] Furthermore, in a specific embodiment, as an upper formwork structure for the construction of a shallow circular silo roof, there are 36 frames in total, and two adjacent frames share a steel pipe upright 3 on a steel beam 7, and the circumferential horizontal bars are disconnected at the steel beam 7 and then connected to the steel pipe upright 3, and the circumferential horizontal bars are 36 broken lines surrounding a circle.

[0050] At the same time, when the spacing between the steel beams 7 is greater than 1.2m, each frame body is provided with four vertical poles along the circumference, and two vertical poles are suspended in the middle of the span; when the spacing between the steel beams 7 is not greater than 1.2m, three vertical poles are provided along the circumference, and one vertical pole is suspended in the middle of the span.

[0051] The invention discloses a construction method for a large-spacing steel beam upper formwork frame structure, comprising using the large-spacing steel beam upper formwork frame structure mentioned above, and the construction method comprises the following steps:

[0052] a. Before hoisting, place the landing point of the steel pipe upright pole 3 on the steel beam 7, and weld the φ20 short steel bar head of the positioning steel pipe upright pole 3;

[0053] b. Fully hang the safety net 1 on the steel beam 7;

[0054] c. Lay scaffolding boards 2 on the steel beams 7 to facilitate workers to walk on them, transfer materials and perform construction work, and leave space for the steel pipe uprights 3 to land;

[0055] d. On the upper surface of the steel beam 7 Figures 2 - 7 As shown, a steel pipe vertical pole 3, a steel pipe circumferential horizontal pole 5 and a steel pipe radial horizontal pole 6 are set up; the steel pipe vertical pole 3 is sleeved on the short steel bar head (not welded), arranged perpendicular to the upper surface of the steel beam 7, and connected with the circumferential horizontal pole and the radial horizontal pole to form a whole; three circumferential horizontal poles are arranged vertically, and the spacing is the same; the radial horizontal pole cooperates with the steel pipe circumferential horizontal pole 5 to sequentially set the lower radial horizontal pole 14, the middle radial horizontal pole 15, and the upper radial horizontal pole 16 from bottom to top; among them, the lower radial horizontal pole 14 is a sweeping pole, the middle radial horizontal pole 15 is a horizontal pole, and the upper radial horizontal pole 16 is a diagonal pole;

[0056] e. Above the scaffolding board 2, Figures 2 - 7 As shown, two steel pipe uprights 4 are erected, which are arranged perpendicular to the upper surface of the scaffolding board 2, erected in the air, and connected with the annular horizontal bars and radial horizontal bars to form a formwork frame as a whole.

[0057] The construction method of the present invention can be used to set up the formwork frame at the steel beam area to support the upper structure, and can also be used to set up the formwork frame at the hole opening to replace the steel beam 7 with the hole opening.

[0058] The present invention is explained in detail based on a specific embodiment below.

[0059] The present invention is used for the construction of the roof of a shallow circular silo. The roof of the shallow circular silo is a truncated cone with a top radius of 5m, a bottom radius of 15m, a height of 4.7m, and a generatrix angle of 23 degrees. The full-frame frame (formwork frame) between every two steel beams 7 is a frame, and there are 36 frames in total. The adjacent two frames share the steel pipe upright pole 3 on the steel beam 7. The circumferential horizontal rod is disconnected at the steel beam 7 and then connected to the steel pipe upright pole 3, and the circumferential horizontal rod is 36 broken lines to form a circle.

[0060] Three ring-shaped horizontal bars are arranged vertically, and the distance between two adjacent bars is not more than 1.5m.

[0061] When the spacing between steel beams is greater than 1.2m, each frame is equipped with four vertical poles along the circumference, and two vertical poles are suspended in the middle of the span; when the spacing between steel beams is not greater than 1.2m, three vertical poles are installed along the circumference, and one vertical pole is suspended in the middle of the span. An inclined pole (with an angle of 23 degrees) is installed on the top of the frame, and the sweeping pole is 0.2m above the ground. The spacing between radial horizontal poles is not greater than 1.5m.

[0062] Pole: See Figure 4 Starting from the poured concrete silo wall 9 (hereinafter referred to as silo wall), the first radial vertical pole is 0.3m away from the silo wall, and the radial spacings of the 2nd to 11th radial vertical poles are 0.8m, 0.8m, 6*0.95m, and 2*1.2m respectively.

[0063] See also Figure 4 The height of the first radial pole from the warehouse wall is 0.5m, and the heights of the 2nd to 11th radial poles are 1m, 1.4m, 1.8m, 2.2m, 2.5m, 2.9m, 3.3m, 3.7m, 4.2m, and 4.7m respectively.

[0064] See also Figures 5 - 7 The circumferential spacing of the 1st to 9th radial uprights from the warehouse wall are 850mm, 790mm, 740mm, 680mm, 620mm, 560mm, 500mm, 440mm, and 380mm respectively, and the circumferential spacing of the 9th to 11th radial uprights are 490mm and 410mm respectively.

[0065] The top of the radial vertical pole protrudes 50 mm above the upper circumferential horizontal pole and the upper radial horizontal pole.

[0066] Steel pipe radial horizontal pole: Refer to Figure 4 , and a bottom bar is provided 0.2 m above the ground for all. One radial diagonal bar is provided at the top of the 1st - 5th radial vertical poles starting from the silo wall. For the 5th - 9th radial vertical poles, 2 horizontal bars (middle radial horizontal bar 15) are provided at an interval of 1.5 m. For the 9th - 11th radial vertical poles, 3 horizontal bars (middle radial horizontal bar 15) are provided at an interval of 1.5 m.

[0067] Steel pipe circumferential horizontal pole: Refer to Figure 4 , and a bottom bar is provided 0.2 m above the ground for all. One circumferential horizontal bar is provided at the top of the 1st radial vertical pole starting from the silo wall. For the 2nd - 11th radial vertical poles, 3 horizontal bars (including the bottom bar) are provided, and the horizontal bar spacing equally divides the height of the vertical pole.

[0068] Since the anti - torsion performance of the right - angle fastener 8 is fully utilized in the present invention, it is necessary to strictly control the quality of steel pipes and fasteners. When the tightening torque of the bolt of the right - angle fastener 8 reaches 65 N·m, it shall not be damaged. The mating surface of the steel pipe and the fastener shall be regular and matching, and it must be ensured that they are closely fitted when the steel pipe is fastened. The weight of a single right - angle fastener 8 shall not be less than 1.347 kg. Each right - angle fastener 8 must be tightened and locked, and it must be checked one by one during acceptance. The tightening torque of the fastener bolt reaches 40 - 65 N·m.

[0069] At the same time, in order to reduce the lateral extrusion damage to the ring beam reinforcement system caused by the downward thrust generated before the initial setting of the inclined roof concrete and ensure the safety of the framework, the concrete must be poured in two times. The first time, the gutter, the ring beam and the 1.0 - m - wide inclined roof slab near it are poured. After the initial setting of this concrete (with an interval of 4 - 6 hours), the remaining concrete on the silo top can be continued to be poured to complete the pouring of the to - be - poured concrete silo wall 10.

[0070] The landing - point spacing position of the steel pipe vertical pole - 3 and the steel pipe vertical pole - 4, the spacing of the steel pipe circumferential horizontal pole 5, and the spacing of the steel pipe radial horizontal pole 6 are all determined through simulation and calculation by Midas software.

[0071] On construction sites, it is often found that after the settlement of the foundation of the framework, a small number of vertical poles are suspended at the bottom while the framework remains stable, indicating that the horizontal members have vertical constraints on the vertical poles through fasteners. Referring to the current standard GB 15831-2006 "Steel Pipe Scaffold Fasteners", it is known that the test method for the anti-torsion stiffness performance of right-angle fasteners is that when the anti-torsion moment at the load end is 900 N·m, the displacement value f at the unloaded end ≤ 70 mm. Therefore, the allowable value of the anti-torsion moment of right-angle fasteners can be taken as 900 N·m. For the semi-rigid joints of fastener connections, first assume that they are considered rigid. If the end moment calculated by the midas software is less than 900 N·m, it means that the fasteners are safe and the assumption holds. Based on the above assumption, take a three-span steel pipe scaffold with the middle vertical pole suspended. Without changing the span, the spacing of the vertical poles, the height, and the load at the top of the vertical poles, increase the number of horizontal members, and use the midas software to calculate the joint moment, the internal force of the members, and the deflection in various cases.

[0072] Using the midas software for finite element analysis, two conclusions are obtained after specific calculations. Conclusion 1: Increasing the number of horizontal members can effectively reduce the mid-span deflection. Conclusion 2: Increasing the number of horizontal members can effectively reduce the moment of the horizontal members.

[0073] Application of the conclusion: Considering economy, a three-horizontal-member structure can be adopted as the basic component unit of the framework for this project.

[0074] The conical surface formwork support of the silo roof slab is checked by finite element analysis using the midas software. The model refers to Figure 8 , and the midas simulation calculation results show that:

[0075] Single frame: The larger displacement values are at the horizontal members where the 4th and 5th suspended vertical poles are located in the circumference, with the maximum values being 6.368 mm and 5.87 mm, less than the allowable deflection L / 250 = 8 mm. See Figure 9 . The larger moments occur at the middle horizontal members where the 4th and 5th suspended vertical poles are located in the circumference, with the maximum values being 881.07 N·m and 851.49 N·m, both not greater than the anti-torsion moment of the fasteners 900 N·m. The bending stress of the horizontal member is 881.07 / 4.492 = 196.14 N / m 2 <205 N / m 2 , see Figure 10 .

[0076] Overall: The larger displacement values are at the horizontal members where the 4th and 5th suspended vertical poles are located in the circumference, with the maximum values being 4.68 mm and 4.25 mm, less than the allowable deflection L / 250 = 6 mm. See Figure 11The larger bending moments occur in the middle horizontal bars where the 4th and 5th suspended vertical bars are located on the circumference. The maximum values are 846.595 N·m and 786.045 N·m, both of which are not greater than the anti-torsion moment of the fastener, 900 N·m. For details, see Figure 12 The larger stresses occur in the middle horizontal bars where the 4th and 5th suspended vertical bars are located on the circumference. The maximum value is 191.822 N·m 2 and 164.306 N·m 2 , both of which are not greater than the allowable stress value of 205 N / m 2 . For details, see Figure 13 .

[0077] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, refer to the description in the method section.

[0078] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A formwork support structure on large-spacing steel beams, characterized in that The invention comprises a steel beam platform as an operating platform and a formwork frame erected on the steel beam platform, wherein the formwork frame comprises a safety net (1) and a plurality of scaffolding boards (2), a first steel pipe upright pole (3), a second steel pipe upright pole (4), a steel pipe circumferential horizontal rod (5), and a steel pipe radial horizontal rod (6). The safety net (1) is fully hung on the corresponding steel beam (7) constituting the steel beam platform, and the top of the steel beam (7) is fully covered with the scaffolding boards (2); the first steel pipe upright pole (3) is perpendicular to the upper surface of the steel beam (7); The steel pipe vertical rods (4) are arranged on the surface and installed on the steel beam (7); the steel pipe vertical rods (1) (3) and (4) are arranged perpendicular to the upper surface of the scaffolding board (2) and are suspended without support; the steel pipe vertical rods (1) (3) or the steel pipe vertical rods (2) (4) are connected to the corresponding steel pipe annular horizontal rods (5) and steel pipe radial horizontal rods (6) to form a whole; the steel pipe annular horizontal rods (5) are vertically arranged in three rows, and the lower annular horizontal rods (11), the middle annular horizontal rods (12) and the upper annular horizontal rods (13) are arranged in sequence from bottom to top; A plurality of steel tube annular horizontal bars (5) are arranged along the axial direction of the steel beam (7); the steel tube radial horizontal bars (6) cooperate with the steel tube annular horizontal bars (5) to sequentially arrange lower radial horizontal bars (14), middle radial horizontal bars (15), and upper radial horizontal bars (16) from bottom to top; the formwork frame between each two adjacent steel beams (7) is a frame, and the adjacent two frames share a steel tube vertical bar (3) on the steel beam (7), and multiple frames are arranged to form a large frame in the shape of a whole circle. The formwork frame structure is a steel pipe fastener type full-floor scaffolding, and the intersection of the steel pipe vertical rod one (3) or the steel pipe vertical rod two (4) and the steel pipe circumferential horizontal rod (5) and the steel pipe radial horizontal rod (6) is connected to each other by a right-angle fastener (8); when the spacing of the steel beams (7) is greater than 1.2m, four vertical rods are arranged along the circumference of each frame body, and two vertical rods are suspended in the middle of the span; when the spacing of the steel beams (7) is not greater than 1.2m, three vertical rods are arranged along the circumference, and one vertical rod is suspended in the middle of the span.

2. The formwork support structure on large-spacing steel beams according to claim 1, characterized in that, The three steel pipe annular horizontal bars (5) arranged vertically are arranged at the same spacing.

3. A formwork support structure on large-spacing steel beams according to claim 1, characterized in that, The tops of the first steel pipe upright pole (3) and the second steel pipe upright pole (4) are both protruding from the upper annular horizontal rod (13) and the upper radial horizontal rod (16).

4. The formwork support structure on large-spacing steel beams according to claim 1, wherein As an upper formwork structure used for shallow silo roof construction, the lower radial horizontal rod (14) is a sweeping rod, the middle radial horizontal rod (15) is a horizontal rod, and the upper radial horizontal rod (16) is an inclined rod.

5. A formwork support structure on large-spacing steel beams according to claim 1, characterized in that, As an upper formwork structure used for the construction of a shallow silo roof, there are 36 frame bodies in total, and two adjacent frame bodies share a steel pipe upright pole (3) on a steel beam (7), and the circumferential horizontal rods are disconnected at the steel beam (7) and then connected to the steel pipe upright pole (3), and the circumferential horizontal rods are 36 broken lines surrounding a circle.

6. A construction method for a formwork support structure on large-spacing steel beams, characterized in that, The method comprises using a large-spacing steel beam upper formwork structure as described in any one of claims 1 to 5, and the construction method comprises the following steps: a. Before hoisting, place the steel pipe upright pole (3) on the steel beam (7) to locate its landing point, and weld the short steel bar head of the steel pipe upright pole (3); b. Fully hang the safety net (1) on the steel beam (7); c. Lay the scaffolding board (2) on the steel beam (7), and leave the landing position of the first steel pipe vertical pole (3). d. Erect the first steel pipe vertical pole (3) on the upper surface of the steel beam (7); the first steel pipe vertical pole (3) is sleeved on the short steel bar head, arranged perpendicular to the upper surface of the steel beam (7), and connected with the circumferential horizontal bar and the radial horizontal bar to form an integral whole; three circumferential horizontal bars are arranged vertically; the radial horizontal bars are arranged in sequence from bottom to top as the lower radial horizontal bar (14), the middle radial horizontal bar (15), and the upper radial horizontal bar (16) in cooperation with the steel pipe circumferential horizontal bar (5). e. Erect the second steel pipe vertical pole (4) above the scaffolding board (2), the second steel pipe vertical pole (4) is arranged perpendicular to the upper surface of the scaffolding board (2), erected in suspension, and at the same time connected with the circumferential horizontal bar and the radial horizontal bar to form an integral formwork support.

7. The construction method of a formwork support structure on large-spacing steel beams according to claim 6, characterized in that, The landing spacing positions of the first steel pipe vertical pole (3) and the second steel pipe vertical pole (4), the spacing of the steel pipe circumferential horizontal bar (5), and the spacing of the steel pipe radial horizontal bar (6) are all determined through simulation and calculation by the Midas software.

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