Large-span report hall arc-shaped stepped ceiling

Abstract

The utility model discloses a large span report hall arc shape stair type ceiling, including with the first way conversion layer and the second way conversion layer of wall top surface parallelly arranged, the second way conversion layer sets up below the first way conversion layer, and the first way conversion layer and the second way conversion layer are connected through a plurality of upper hanger rods between, and the top of upper hanger rod is connected on the wall top surface, and the bottom of upper hanger rod projects the plane where the second way conversion layer is located, and the arc surface structure is connected through a plurality of lower hanger rods below the second way conversion layer, and the arc surface structure includes a plurality of C character unit that connects in the ladder form, and C character unit includes first standard section, second standard section, third standard section and fourth standard section, and first standard section includes first circular arc section and first straight section, and second standard section includes second straight section, and third standard section includes second circular arc section, and fourth standard section includes third straight section, and the industry pain point of " complex shape is difficult to mass production " of arc GRG is solved in the application.

Description

Technical Field

[0001] This utility model belongs to the field of large-span suspended ceiling construction technology, specifically, it relates to a large-span auditorium arc-shaped stepped suspended ceiling. Background Technology

[0002] The existing ceiling construction process optimizes the GRG (Glass Reinforced Plastic) model through BIM modeling, facilitating fabrication and installation. A total station and laser level are used to assist in layout, forming a "nine-square grid" positioning control network to effectively control the position of walls with varying elevations and ensure on-site installation accuracy. When the finished GRG surface is more than 400 mm from the wall edge, diagonal bracing is added to the lower end of the horizontal keel to ensure overall stability. For secondary conversion layer structures where the height of the finished GRG product exceeds 1500 mm, "reaction bracing" using angle iron is employed for reinforcement to prevent excessively long threaded rods from causing instability and cracking of the ceiling. Simultaneously, strict quality control is emphasized at each stage of construction, from raw material inspection to keel installation, GRG module installation, and final surface finishing, with detailed quality control standards established. However, existing methods still fall short of fully meeting design requirements in terms of accurately realizing complex shapes; during construction, GRG modules are prone to damage and deviations during installation; and different construction techniques yield inconsistent results in optimizing acoustic performance, making it difficult to precisely achieve the expected acoustic indicators. Therefore, a simple, easy-to-construct, and capable large-span arched stepped ceiling for auditoriums is needed. Utility Model Content

[0003] The purpose of this invention is to provide a large-span arched stepped ceiling for auditoriums that is simple in structure, easy to construct, and meets the expected acoustic performance. Through "modular C-shaped unit decomposition + alphanumeric coding system," the complex shape of the arched stepped GRG ceiling is transformed into a standardized module that can be prefabricated in the factory. This overcomes the bottleneck of traditional arched ceilings, which suffer from "high on-site processing difficulty and low dimensional accuracy," achieving an organic unity between artistic design and industrialized production.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A large-span auditorium with an arc-shaped stepped ceiling includes a first transition layer and a second transition layer parallel to the top surface of the wall. The second transition layer is located below the first transition layer. The first and second transition layers are connected by several upper suspension rods. The top of the upper suspension rods is connected to the top surface of the wall, and the bottom of the upper suspension rods extends out of the plane of the second transition layer. Below the second transition layer, an arc-shaped surface structure is connected by several lower suspension rods. The arc-shaped surface structure includes several C-shaped units connected in a stepped manner. The C-shaped units include a first standard segment, a second standard segment, a third standard segment, and a fourth standard segment. The first standard segment includes a first arc segment and a first straight segment. The second standard segment includes a second straight segment. The third standard segment includes a second arc segment. The fourth standard segment includes a third straight segment.

[0005] The lower suspension rod between the first standard section and the second transition layer is an L-shaped angle steel suspension rod with a second diagonal brace on it. The lower suspension rods between the second standard section and the second transition layer, the lower suspension rods between the third standard section and the second transition layer, and the lower suspension rods between the fourth standard section and the second transition layer are all galvanized round steel suspension rods.

[0006] The top of the first transfer layer is tightly connected to the bottom surface of the frame beam, and the side of the frame beam is connected to the first transfer layer by a first diagonal brace.

[0007] The first and second transition layers have the same structure, both including several intersecting horizontal and vertical bars, with the lower suspension rods located at the junction of the horizontal and vertical bars.

[0008] The first straight section has a groove for mounting light fixtures.

[0009] The sides of the C-shaped units are connected by L-shaped plasterboard.

[0010] A bowl-shaped groove is provided at the joint between the C-shaped units, and the bowl-shaped groove is filled with GRG adhesive powder and mesh cloth.

[0011] This application adopts a "C-shaped unit four-segment combination" design, which decomposes the complex curved stepped ceiling into standardized modules (L-shaped composite panel, straight section, arc section, and straight section). It achieves precise disassembly and assembly through an alphanumeric coding system, solving the industry pain point of "complex shape and difficulty in mass production" of curved GRG.

[0012] This application employs a rigid-flexible connection system to ensure the "arc precision + structural safety" of the GRG. Differentiated connections are used for different shaped sections: the standard section 1 / 2 (circular arc + straight line) uses L-shaped and straight angle steel hangers for rigid welding, which has strong resistance to deformation; the standard section 3 / 4 (pure circular arc / sloping surface) uses φ10 round steel hangers + double nuts for flexible adjustment, which not only ensures the accuracy of the arc curvature, but also releases stress through "flexible nodes" to avoid plate cracking. Attached Figure Description

[0013] Figure 1 This is a schematic elevation view of the arc-shaped stepped GRG ceiling of this utility model.

[0014] Figure 2 This is a schematic diagram of the structure of the C-shaped unit connection in this utility model.

[0015] Figure 3 This is the electromechanical point diagram of this utility model.

[0016] Figure 4 This is the block coding diagram of this utility model.

[0017] Figure 5 This is a schematic diagram of the structure of the first conversion layer in this utility model.

[0018] Figure 6 This is a schematic diagram of the structure of the first conversion layer at the fan duct in this utility model.

[0019] Figure 7 This is a schematic diagram of the structure of the second conversion layer at the fan duct in this utility model. Detailed Implementation

[0020] like Figure 1-7As shown, a large-span auditorium with an arc-shaped stepped ceiling includes a first transition layer 2 and a second transition layer 3 arranged parallel to the top surface 1 of the wall. The second transition layer 3 is located below the first transition layer 2. The first transition layer 2 and the second transition layer 3 are connected by several upper suspension rods 4. The top end of the upper suspension rods 4 is connected to the top surface 1 of the wall, and the bottom end of the upper suspension rods 4 extends out of the plane where the second transition layer 3 is located. Below the second transition layer 3, an arc-shaped surface structure is connected by several lower suspension rods 5. The arc-shaped surface structure includes several C-shaped units 6 connected in a stepped manner. The C-shaped unit 6 includes a first standard segment 25, a second standard segment 26, a third standard segment 27, and a fourth standard segment 28. The first standard segment 25 includes a first arc segment 7 and a first straight segment 8. The second standard segment 26 includes a second straight segment 9. The third standard segment 27 includes a second arc segment 10. The fourth standard segment 28 includes a third straight segment 11. The lower suspension rod 5 between the first standard section 25 and the second transition layer 3 is an L-shaped angle steel suspension rod with a first diagonal brace 12 installed on it. The lower suspension rods 5 between the second standard section 26 and the second transition layer 3, the third standard section 27 and the second transition layer 3, and the fourth standard section 28 and the second transition layer 3 are all galvanized round steel suspension rods. The top of the first transition layer 2 is tightly connected to the bottom surface of the frame beam 13, and a second diagonal brace 14 is installed between the side of the frame beam 13 and the first transition layer 2. The first transition layer 2 and the second transition layer 3 have the same structure, both including several vertically intersecting horizontal bars 15 and vertical bars 16, with the lower suspension rod 5 located at the intersection of the horizontal bars 15 and vertical bars 16. The first straight section 8 has a groove for installing the lamp 23. The sides of the connection between the C-shaped units 6 are connected by L-shaped gypsum board 17. A bowl-shaped groove is provided at the joint between the C-shaped units 6, and the bowl-shaped groove is filled with GRG adhesive powder and mesh cloth.

[0021] This application is implemented through the following seven steps during actual construction: (1) Curved GRG layout design and production; Specifically, 1) The layout design adopts a modular curved stepped GRG layout design, and the organic unity of architectural sound field and decorative effect is achieved through acoustic optimization; 2) Key Points of Detailed Design ① The layout system adopts a layout system with straight edges at both ends and an arc-shaped stepped staggered middle section; ② Each modular arc-shaped stepped GRG C-shaped unit 6 includes a first standard segment 25, a second standard segment 26, a third standard segment 27, and a fourth standard segment 28; the first standard segment 25 includes a first arc segment 7 and a first straight segment 8. The first arc segment 7 is a quarter-circle arc with a radius of 225mm. The first straight segment 8 has a recess for a light fixture 23, with the light fixture 23 embedded in the recess. A total of 6 symmetrically distributed connection points are set (3 for the arc segment and 3 for the straight segment). The second standard segment 26 includes a second straight segment 9, with 6 symmetrically distributed connection points arranged in two rows. The third standard segment 27 includes a second arc segment 10, with 4 symmetrically distributed connection points. The fourth standard segment 28 includes a third straight segment 11, with 4 symmetrically distributed connection points. ③ Each panel is coded using a combination of letters and numbers. The first and last rows (rows A and Z) are panels with straight edges at both ends, corresponding to straight and curved long sides of the GRG structure, respectively. Within each row, panels are numbered sequentially from 1 to N based on their size differences (e.g., A1, A2...). The C-shaped units 6 in the non-first and last rows use a uniform design within each standard section to ensure consistent dimensions and meet the needs of modular processing and production. This coding system decomposes the GRG panel 18 into several smaller modules, with each panel pre-embedded with 4-6 Z-shaped galvanized embedded parts 19 for hanger connections. Pre-fabrication is then carried out in the factory according to the exploded view.

[0022] 3) Modular assembly The C-shaped unit 6 is provided with a flange with connecting holes at the joint and is spliced ​​together with locking bolts to form a whole. The C-shaped units 6 are arranged in a staggered manner without overlapping. Specifically, the side is connected to the adjacent C-shaped unit 6 with L-shaped gypsum board 17. Hidden light strips are preset in the inside corner to realize the integration of ceiling lighting. GRG uses a seamless process, with interlocking bolts connecting the panels. A bowl-shaped groove is pre-reserved at the joint, and the groove is filled with GRG adhesive powder and mesh cloth. 4) Functional point layout The locations of ventilation openings 20, fire sprinklers 21, low-voltage intelligent systems, ventilation and air conditioning 22, lighting fixtures 23, and inspection ports 24 in the ceiling are all concentrated at both ends and the second straight section 9 of the second standard section 26 of the C-shaped unit 6, and are evenly distributed.

[0023] (2) Design and stress verification of keel and connection nodes; specifically, 1) BIM technology is used to integrate the layout of electromechanical pipelines and ceiling keel, and the vertical keel positioning is optimized based on the superposition analysis of pipeline layout drawing and frame structure beam plan. The specific construction process is as follows: The ceiling joists and the electromechanical pipeline joists are arranged in a coordinated manner, and the columns and transition layer beams avoid the electromechanical pipelines to eliminate spatial conflicts; and two transition layers are set according to the height of the hangers. The first transition layer 2 is attached to the bottom of the frame beam 13 and fixed thereto. The horizontal keel is disconnected when it encounters the fan 29 and the duct 30. The second transition layer 3 is arranged at the top of the fourth section of the GRG plate 18 assembly section and is located below the first transition layer 2. Then, the counter-support structure is set on both sides of the frame beam 13 and the fan 29 and the duct 30. 2) Special area treatment: At the installation location of large-size fan 29 and duct 30, the first conversion layer 2 is set in sections, and the second conversion layer 3 is set in sections; 3) Connection method between the second conversion layer 3 and GRG The first standard section 25 and the second standard section 26 of the C-shaped unit 6 are rigidly supported and welded to the GRG plate 18 Z-shaped embedded part 19 by galvanized angle iron hangers; the third standard section 27 and the fourth standard section 28 are flexiblely supported and connected to the GRG plate 18 Z-shaped embedded part 19 by φ10 hangers. 4) The back keel of L-shaped gypsum board 17 and the connecting rod of the first standard section 25 of C-shaped unit 6 are shared, thus optimizing the keel structure layout; 5) Structural stress verification and testing.

[0024] (3) Welding of steel frame transition layer; Specifically, a full-span operating platform is erected under the ceiling as the working surface for keel installation. The initial height of the operating platform is set at 500mm below the bottom of the second transition layer 3 elevation. After the frame welding is completed, the platform is lowered to the bottom of GRG plate 18 at an elevation of 1.8m to provide operating space for subsequent GRG installation. The welding construction strictly follows the keel positioning parameters determined by the detailed design. Specifically, the vertical hanger frame is welded first. After the electromechanical pipeline installation is accepted, the first transition layer 2 is welded, and the reinforcement work of the anti-support structure is completed simultaneously. Then the second transition layer 3 is welded. After all welds pass the appearance quality inspection, anti-rust paint is applied in time to ensure corrosion resistance.

[0025] (4) Lower hanger 5 is fixed; specifically, the lower hanger 5 adopts angle steel hanger and galvanized round steel hanger. When the lower hanger 5 adopts angle steel hanger, the angle steel hanger is adapted to the shape of GRG plate 18. When GRG plate 18 is flat, straight angle steel hanger is adopted. At the first standard section 25 of the first arc section 7 and the first straight section 8 of C-shaped unit 6, straight angle steel hanger is combined with L-shaped angle steel hanger, and angle iron diagonal bracing is set to form a triangular stable state. At the third standard section 27 and the fourth standard section 28 of C-shaped unit 6, galvanized round steel hanger is used to connect. Next, during the actual construction, the position of the embedded part 19 is first determined according to the GRG layout drawing. Then, the positioning drawing of the hanger is generated according to the positioning of the embedded part 19 to ensure that the corresponding deviation between the hanger and the embedded part 19 does not exceed 5mm. The welding of the hanger follows the elevation sequence of the 6 steps of the C-shaped unit, and the welding is carried out from the low elevation to the high elevation to avoid positioning deviation caused by cross-operation. At the same time, the elevation control line is projected using a laser level and the installation elevation line of each GRG plate 18 is marked on the surface of the hanger. The marking error is controlled within ±2mm to provide a precise benchmark for the subsequent plate installation.

[0026] (5) Installation of arc-shaped GRG; The installation construction follows the principle of finishing the edges first and then the main body. First, the GRG plate 18 of the first straight section is fixed. Specifically, the hanger is cut to the design length according to the layout elevation. After precise alignment, it is welded and fixed to the embedded part 19 of the GRG plate 18. The weld length is not less than 50mm to ensure a firm connection. When entering the installation stage of the first group of C-shaped units 6, the first standard section 25, the second standard section 26, the third standard section 27 and the fourth standard section 28 are constructed in sequence. Installation of the first standard section 25: Set up an adjustable height stirrup on the operating platform, and place the GRG plate 18 stably on the stirrup for auxiliary positioning; weld the embedded part 19 on the back of the arc section first, and fix it to the embedded part 19 by full welding with the L-shaped angle iron, and then fix it to the embedded part 19 by full welding with the straight angle iron to form a rigid connection node. The stirrup can be removed after cooling for more than 30 minutes after welding. Installation of the second standard section 26: First, adjust the design position of the GRG elevation and temporarily connect it with the first standard section 25. Then, use two M10 fixing bolts to temporarily fix the 150mm long 50x3 galvanized angle iron to the first standard section 25 and the second standard section 26 and level the joint. Then, weld the straight angle iron to the 6 embedded parts 19 in sequence and use M6 stainless steel bolts to tighten the joint to form a whole. Installation of the third standard section 27: First, connect and fix the hanger to the angle bracket, and then connect the angle bracket to the embedded part 19 of the GRG plate 18 with bolts; use the double nut structure of the hanger and the angle bracket to finely adjust the plate elevation. After confirming the elevation, connect the third standard section 27 to the fixed second standard section 26. Use two M10 fixing bolts to temporarily fix the 150mm long 50x3 galvanized angle iron, the second standard section 26 and the third standard section 27 and level the joint. Then use M6 stainless steel bolts to tighten the joint to form an integral unit. Section 4, Standard Section 28: The construction steps are completely consistent with those of Section 3, Standard Section 27. After installation, the flatness of the entire C-shaped unit 6 should be checked, and the deviation should be controlled within 3mm. When installing the second and subsequent C-shaped units 6, since each group of units adopts a stepped staggered design, there will be a difference in elevation between adjacent units. The ventilation and air conditioning 22 air outlets need to be installed at the side openings simultaneously. The outside of the air outlets is sealed with 12mm thick gypsum board. The sealing board is fixed by L-shaped angle steel brackets. The brackets are welded to the conversion layer to ensure that they are flush with the surface of the GRG board 18, with an error of no more than 2mm.

[0027] (6) Mechanical and electrical point opening and joint treatment; the mechanical and electrical point opening shall be strictly in accordance with the point distribution map of the detailed design. Before opening the hole, the correspondence between the 18 GRG board codes and the mechanical and electrical point numbers shall be checked to ensure the accuracy of the opening position. The opening shall be carried out with a special diamond circular saw blade with a diameter that matches the opening size. During the cutting process, the saw blade shall be kept perpendicular to the board surface with a perpendicularity deviation of ≤1° to avoid chipping or missing corners at the hole edge. After the opening is completed, the hole opening shall be polished. Then, the fire sprinkler heads 21 and the end points of the air vents shall be installed. The installation gap shall be filled with fireproof sealant to ensure the unity of function and decoration. The joint treatment of the 18 GRG boards follows the principle of prioritizing crack prevention while also considering aesthetics. The specific process is as follows: Pre-treatment: Sand the board surface within 50mm on both sides of the joint with 80-grit sandpaper to remove loose dust and burrs, and clean the debris in the gap with compressed air at a pressure of 0.4MPa; Reinforcement treatment: Lay 100g / m² alkali-resistant fiberglass mesh at the joint, ensuring that the mesh covers ≥50mm on both sides of the joint, and fix it with GRG special adhesive powder to ensure that there are no air bubbles or peeling. Filling and leveling: Use GRG adhesive powder to fill the joints in layers, with each layer ≤5mm thick. The last layer of filling should be 1-2mm lower than the board surface. During the filling process, use a scraper to compact it to avoid hollow areas. Overall finishing: Under the condition of ambient temperature ≥15°, after the filling material has cured for 48 hours, use 240-grit sandpaper to sand it until it is flush with the board surface, with the deviation controlled within ≤0.5mm; The seams of the end trim panels and all C-shaped units form a continuous whole, ultimately achieving a seamless visual effect on the ceiling surface and meeting the acoustic performance requirements for interface integrity.

[0028] (7) GRG finishing treatment. Before applying the finishing finish, complete the following protective measures: For the electromechanical terminal points on the GRG board 18, a plastic film is used to fully cover and wrap them, and 20mm wide masking tape is used to seal and fix them along the edges to ensure that contaminants do not penetrate into the points during the spraying operation; Wall treatment follows the principle of layered construction and progressive sanding, specifically including: Surface preparation: First, use 240-grit sandpaper to sand the entire 18 sides of the GRG board, focusing on the seams and the area around the openings, to remove surface dust, burrs and protrusions. After sanding, use a vacuum cleaner with a suction power of ≥15kPa to clean the dust. Putty application: Use GRG special water-resistant putty, apply in two coats. The first coat is 1-2mm thick, and the second coat is 0.5-1mm thick. The interval between each coat is ≥24 hours. After the second coat of putty dries, sand it with 320-grit sandpaper until the surface smoothness is ≤2mm, and check with a 2m straightedge. Coating application: The primer is an epoxy sealing primer, with a spray thickness of 30-40μm, ensuring complete coverage of the board surface without any missed areas. The first coat of topcoat is sprayed with a thickness of 20-30μm, and after drying for more than 4 hours, it is lightly sanded with 400-grit sandpaper to remove particles. The second coat of topcoat is sprayed with the same specifications, with a total dry film thickness of ≥80μm, ensuring uniform color. After coating, it is cured for 7 days. During the curing process, strong winds and impacts should be avoided. The final surface should meet the acceptance standard of no drips, no needle marks, and no obvious brush marks, forming a seamless decorative effect with the joint treatment.

[0029] The GRG curved ceiling of this application adopts a modular design of "C-shaped unit four-segment combination," breaking down the complex curved ceiling into standardized modules. Through a clear letter + number coding system, it achieves precise connection from design to production and installation. The pre-set standardized connection points and splicing structure of each module greatly reduce the difficulty of on-site construction, making complex curved shapes technically easy to achieve, and allowing for orderly progress even when facing large and irregularly shaped ceiling projects.

[0030] This application adopts a layout system of "straight edges at both ends + arc-shaped stepped staggered layers in the middle". Based on the principle of acoustic reflection, the overall arc is decomposed into standardized C-shaped unit combinations to form a unique sailboat-like canvas staggered effect. It not only meets the acoustic performance requirements, but also achieves innovative decorative shape, breaking the limitations of traditional ceiling design in terms of function and artistic expression.

[0031] This application employs a rigid-flexible connection system for different shaped sections. The first standard section 25 uses L-shaped angle steel hangers for rigid welding, and the second standard section 26 uses straight angle steel hangers for rigid welding to ensure resistance to deformation. The third standard section 27 and the fourth standard section 28 use φ10 round steel hangers with double nuts for flexible adjustment. While ensuring the accuracy of the arc curvature, this effectively releases temperature stress and prevents the panels from cracking. This innovative connection method solves the key problems of structural safety and shaped accuracy in curved ceilings.

[0032] GRG material itself is relatively expensive, but due to its modular design and factory prefabrication, on-site cutting waste is reduced. Furthermore, by optimizing the processing scheme and standardizing the GRG modular design, mold utilization is increased by approximately 100%, saving mold production costs. Meanwhile, although the steel and other materials used in the double-layer transition layer and anti-support system are used in large quantities, efficient material utilization is achieved through reasonable structural design, ensuring structural safety. In addition, the factory-prefabricated modular panels reduce complex on-site processing steps; only splicing and fixing are required, reducing labor costs. Furthermore, this application ensures the quality of the ceiling through full-process quality control, such as stress verification, 19mm pull-out tests of embedded parts, and decorative surface treatment, reducing maintenance costs caused by cracking and deformation. The inherent durability of GRG material also means that the ceiling does not need frequent replacement during long-term use, further reducing maintenance costs. On the other hand, the innovative acoustic design and decorative effects of this application create a high-quality interior space, enhancing the overall value of the building.

[0033] In summary, the construction process of the curved GRG ceiling proposed in this application is highly feasible and innovative in terms of technology, and can achieve complex shapes and good acoustic effects. In terms of economy, although the initial investment in materials and equipment is relatively large, it has significant economic benefits in terms of cost reduction, shortening of construction period and reduction of maintenance by optimizing the design and construction process. Overall, it has a high cost performance and promotion and application value.

[0034] The above embodiments are only used to illustrate and not limit the technical solutions of this utility model. Although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the utility model without departing from the spirit and scope of the utility model. Any modifications or partial substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A large-span auditorium with an arched stepped ceiling, characterized in that: It includes a first transition layer and a second transition layer set parallel to the top surface of the wall. The second transition layer is located below the first transition layer. The first and second transition layers are connected by several upper hanging rods. The top of the upper hanging rods is connected to the top surface of the wall, and the bottom of the upper hanging rods extends out of the plane where the second transition layer is located. Below the second transition layer, there is an arc-shaped surface structure connected by several lower hanging rods. The arc-shaped surface structure includes several C-shaped units connected in a stepped manner. The C-shaped unit includes a first standard segment, a second standard segment, a third standard segment, and a fourth standard segment. The first standard segment includes a first arc segment and a first straight segment. The second standard segment includes a second straight segment. The third standard segment includes a second arc segment. The fourth standard segment includes a third straight segment.

2. The large-span auditorium arc-shaped stepped ceiling according to claim 1, characterized in that: The lower suspension rod between the first standard section and the second transition layer is an L-shaped angle steel suspension rod with a second diagonal brace on it. The lower suspension rods between the second standard section and the second transition layer, the lower suspension rods between the third standard section and the second transition layer, and the lower suspension rods between the fourth standard section and the second transition layer are all galvanized round steel suspension rods.

3. The large-span auditorium arc-shaped stepped ceiling according to claim 2, characterized in that: The top of the first transfer layer is tightly connected to the bottom surface of the frame beam, and the side of the frame beam is connected to the first transfer layer by a first diagonal brace.

4. The large-span arched stepped ceiling for a lecture hall according to claim 3, characterized in that: The first and second transition layers have the same structure, both including several intersecting horizontal and vertical bars, with the lower suspension rods located at the junction of the horizontal and vertical bars.

5. The large-span arched stepped ceiling for a lecture hall according to claim 4, characterized in that: The first straight section has a groove for mounting light fixtures.

6. The large-span auditorium arc-shaped stepped ceiling according to claim 5, characterized in that: The sides of the C-shaped units are connected by L-shaped plasterboard.

7. The large-span arched stepped ceiling for a lecture hall according to claim 6, characterized in that: A bowl-shaped groove is provided at the joint between the C-shaped units, and the bowl-shaped groove is filled with GRG adhesive powder and mesh cloth.

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