A full-process integrated construction method for a semicircular cantilever type super-high and large-span report hall

Abstract

The application provides a full-process integrated construction method for a semicircular cantilever type ultrahigh large-span report hall, comprising: reinforced concrete bottom plate construction and semicircular embedded part embedding; semicircular core area temporary support system construction; first layer semicircular core large-span type steel beam and outer ring inclined column synchronous construction; one layer top type steel auxiliary structure construction; steel bar truss floor support plate laying and concrete pouring; second layer cantilever roof type steel beam and resting type stepped stand synchronous construction; roof cantilever floor support plate construction and stand fine forming; curtain wall construction; cantilever roof structure and one layer rough decoration synchronous construction; one layer and two layer fine decoration and ultrahigh arc ceiling construction. The application is full-process annular symmetrical construction, arc precise positioning, completely solves the problems of large deviation of special-shaped structure, unsymmetrical stress and cantilever end sinking, cooperates with the resting type stand construction method and the lower hanging and upper pulling type arc ceiling technology, and realizes the full-process integration, high precision, high efficiency and high safety from foundation embedding to fine decoration delivery.

Description

Technical Field

[0001] This invention belongs to the field of building construction technology, and in particular relates to an integrated construction method for a semi-circular cantilevered ultra-high and large-span auditorium. Background Technology

[0002] The semi-circular cantilevered, ultra-high, large-span auditorium is a large-span, irregularly shaped public building with an overall arc-shaped symmetrical structure. The first floor adopts an outer ring of inclined columns and a curtain wall system, while the second floor has a large-span cantilevered steel roof structure. It is also equipped with complex structures such as hanging corridors, sunken courtyards, tiered stands, and ultra-high space interior decoration. The construction is characterized by the difficulty of arc positioning, strict control of the stress on the cantilever structure, high precision of inclined column installation, and dense cross-disciplinary collaboration.

[0003] Existing construction techniques have the following significant technical defects for this type of semi-circular cantilevered auditorium:

[0004] 1. The overall structure is a semi-circular arc shape. The positioning accuracy of the arc shape of the embedded parts of the base plate, temporary supports, arc steel beams, and outer ring inclined columns is difficult to control. Conventional straight-line construction process is prone to arc deviation and asymmetrical stress.

[0005] 2. The second-floor roof is a cantilevered steel structure with no lower support, making it extremely difficult to control installation deformation and deflection. Traditional step-by-step construction can easily lead to the cantilever end sinking and the overall structure becoming unstable.

[0006] 3. The outer ring inclined columns of the first floor have poor compatibility with the curved main steel beams and curtain wall keel. The inclined column installation tilt angle and the curved positioning deviation are large, which leads to misalignment and difficulty in finishing the curtain wall installation in the later stage.

[0007] 4. Traditional tiered grandstands require rebar installation and pre-installation, which can easily damage the load-bearing system of the semi-circular floor slab and cantilever structure, resulting in complicated construction procedures and poor structural integrity.

[0008] 5. The ceiling height exceeds 20m and the span exceeds 56m. It is a semi-circular arc ceiling. Conventional hanging technology cannot be adapted to the arc shape and the extra-long hanging rods, which poses safety and quality hazards such as ceiling deformation, falling off, and uneven curvature.

[0009] 6. The main structure, cantilevered roof, inclined columns, curtain wall, grandstand, and decoration processes are disconnected, and there is no integrated construction system suitable for the semi-circular irregular structure, resulting in a long construction period and great difficulty in quality control.

[0010] Currently, there is no mature and integrated construction technology for combined auditoriums with semi-circular integral structures, two-story cantilevered structures, outer ring inclined columns, and ultra-high spans, which cannot solve core challenges such as arc positioning, cantilever control, grandstand construction, and ultra-high ceilings. Therefore, this invention proposes a fully integrated construction method for semi-circular cantilevered ultra-high span auditoriums, filling a technological gap. Summary of the Invention

[0011] To address the shortcomings of existing technologies, this invention provides a fully integrated construction method for a semi-circular cantilevered, ultra-high, large-span auditorium. Targeting five core characteristics—a semi-circular arc structure, a two-story cantilevered roof, a single-story outer ring of inclined columns, a suspended, unsupported grandstand, and an ultra-high, large-span arc ceiling—the invention optimizes the entire construction process, develops specific parameters for arc positioning, anti-deformation technology for the cantilever structure, construction methods for the suspended grandstand, and a bottom-hanging, top-pulling arc ceiling process. This achieves a fully integrated, high-precision, high-efficiency, and high-safety construction process from foundation pre-embedding to finished product delivery.

[0012] The present invention achieves the above-mentioned technical objectives through the following technical means.

[0013] A fully integrated construction method for a semi-circular cantilevered, ultra-high, long-span auditorium includes the following processes:

[0014] Step 1: Construct the reinforced concrete base slab and embedded parts;

[0015] Step 2: Construction of temporary support system in the core area;

[0016] Step 3: The first layer of semi-circular core large-span steel beams and outer ring inclined columns are constructed simultaneously;

[0017] Step 4: Construction of the first-floor roof steel auxiliary structure;

[0018] Step 5: Laying of steel truss floor decking and pouring of concrete;

[0019] Step 6: The steel beams of the second-floor cantilevered roof and the suspended tiered grandstand are constructed simultaneously;

[0020] Step 7: Construction of the cantilevered roof deck slab and refined shaping of the grandstand;

[0021] Step 8: Curtain wall construction;

[0022] Step 9: The cantilevered roof structure is constructed simultaneously with the first-floor rough finishing;

[0023] Step 10: Construction of the first and second floor interior decoration and ultra-high curved ceiling.

[0024] Further, step 1 includes:

[0025] After leveling and compacting the site, a 100mm thick plain concrete foundation layer is poured. Following the semi-circular building axis, an arc-shaped layout is established, and HRB400E grade 16mm diameter reinforcing bars are tied to the base slab in a double-layer, bi-directional arrangement with a spacing of 150mm and a 40mm thick protective layer. Temporary support steel plates with a thickness of 20mm are precisely embedded along the semi-circular radial direction and fixed to the main reinforcing bars of the base slab on three sides using an arc-shaped positioning frame. A 400mm thick waterproof reinforced concrete base slab is poured, symmetrically vibrated and compacted along the semi-circular arc, and then cured with moisture.

[0026] Further, step 2 includes:

[0027] Using the radial embedded parts of the base plate as the foundation, a temporary steel support system for the core area is erected symmetrically along a semi-circular radial direction. The support columns of the temporary support system are made of Q355B steel H-beams with dimensions of H300×200×10×14. The support columns are arranged in a radial arc shape, and the support columns are arranged according to the stress points of the semi-circular core large-span steel beam. After the temporary support system is erected, a preload is applied. The preload is 1.2 times the total construction load, held for 24 hours, and the support settlement is ≤5mm to eliminate inelastic deformation.

[0028] Further, step 3 includes:

[0029] After the temporary support system passed acceptance, the first-layer semi-circular core large-span steel beam and outer ring inclined columns were hoisted symmetrically in sections along the semi-circle to achieve synchronous stress on the arc-shaped structure. The semi-circular core large-span steel beam is an arc-shaped H-beam made of Q355B steel with dimensions of H1800×600×30×40 and a maximum span of 56m. It is arranged radially along the semi-circle, and the beam is cambered at 1 / 500 of the span with a camber height of 112mm and an arc curvature deviation of ≤2mm. The first-layer outer ring inclined columns are box-shaped arc-shaped inclined columns with a cross-section of 400×400×16mm made of Q355B steel. They are arranged in a ring around the outer circle of the semi-circle with an installation tilt deviation of ≤0.5° and a ring positioning deviation of ≤3mm. The components are connected by high-strength bolts, and the joints are made of full-penetration first-class welds. After the welds are completed, ultrasonic non-destructive testing is performed. After passing the test, a stable semi-circular steel frame is formed.

[0030] Furthermore, in step 4, the first-floor roof steel auxiliary structure includes a first-floor roof steel structure hanging corridor, a first-floor roof steel sunken courtyard, and a first-floor roof steel ring ditch, all constructed simultaneously.

[0031] Step 8 includes: the curtain wall is arranged in a semi-circular ring and galvanized arc-shaped steel keel is used; after the keel is installed, the arc-shaped curtain wall panel is installed, neutral silicone weather-resistant sealant is applied, and a continuous water spray test is carried out after construction to ensure that there is no leakage at the ring-shaped end.

[0032] Further, step 5 includes: laying a steel truss floor deck on the first layer of semi-circular core large-span steel beam, cutting it along the arc to fit, and using hot-rolled ribbed steel bars with a diameter of 8mm and a strength grade of 400MPa for the truss reinforcement; the steel truss floor deck is fixed to the semi-circular core large-span steel beam by welding with studs, with a stud spacing of 300mm, and denser arrangement at the arc-shaped end; after binding the upper layer of reinforcement, pour concrete with a thickness of 120mm, pouring symmetrically along the semi-circle, and keeping it moist for curing.

[0033] Further, step 6 includes:

[0034] The second-floor cantilevered roof steel beams were hoisted in symmetrical segments along a semi-circular radial direction. Their material, specifications, and connection process were consistent with the first-floor semi-circular core large-span steel beams. Temporary bracing was installed at the cantilever ends to strictly control the cantilever deflection to ≤1 / 800 of the span. Simultaneously, a first-floor semi-circular reinforced concrete stepped grandstand was constructed using a suspended construction method, without any rebar installation or pre-installed reinforcement. The specific construction method is as follows:

[0035] The semi-circular grandstand is constructed using a pre-formed arc template, eliminating the need for on-site rebar installation or pre-reserved reinforcement. The grandstand's steel reinforcement framework is directly placed on the support base. The grandstand is constructed using cast-in-place concrete, with a step height of 160mm, a width of 350mm, and a slab thickness of 100mm. It is equipped with double-layer, bidirectional steel reinforcement with a spacing of 150mm. The template is supported by a disc-lock scaffold with a vertical pole spacing of 0.9m × 0.9m and a step distance of 1.5m.

[0036] Further, step 7 includes:

[0037] Steel truss floor slabs of the same specification are laid on the steel beams of the cantilevered roof on the second floor. The cantilevered section is fixed with dense studs and concrete is poured. The construction process is the same as that of the steel truss floor slabs on the ground floor. At the same time, the semi-circular stepped grandstand is finished with concrete surface finishing, straightening of the arc, sealing of construction joints, and moisture curing. The curvature, slope and step size of the grandstand are finely adjusted.

[0038] Further, step 9 includes:

[0039] The roof structure layer is constructed on the second-floor cantilever roof slab: 1.5mm thick polyurethane waterproof coating + 50mm thick extruded polystyrene board insulation layer + 60mm thick C20 fine stone concrete protective layer, with waterproof finishing treatment at the cantilever end; the rough finishing of the walls and floor of the first-floor semi-circular hall is constructed simultaneously, with the walls leveled with cement mortar and the floor poured with a concrete slab, ensuring straight internal and external corners.

[0040] Further, step 10 includes:

[0041] The lobby on the first floor features a semi-circular arched ceiling, constructed using a specialized bottom-hanging and top-pulling technique, as detailed below:

[0042] The upper layer is fixed to the second-layer cantilever steel beam by welding hot-dip galvanized threaded rods, and the lower layer is equipped with hot-dip galvanized reverse tie rods, which are symmetrically arranged along a semi-circular ring to form a two-way force system. The spacing between the hangers and tie rods is ≤1200mm and the distance from the wall is ≤1800mm.

[0043] Curved keel system: U-shaped light steel curved main keel with wall thickness ≥1.2mm and spacing ≤1200mm, secondary keel spacing 600mm, ceiling adapted to semi-circular arc, arched according to 1 / 800 of span;

[0044] Reinforcement measures: When the length of the hanger exceeds 2500mm, add a ring-shaped steel structure counter-bracing with a spacing of ≤3600mm and set up adjacent to each other to prevent deformation of the arc-shaped keel;

[0045] Simultaneously complete the fine decoration of curved walls and floors, control the deviation of squareness of inside and outside corners, and ensure that the overall circular appearance is smooth and straight.

[0046] The present invention has the following beneficial effects:

[0047] 1. Strong adaptability to irregular structures: Specialized construction techniques for overall semi-circular structures, two-story large cantilever structures, and outer ring inclined columns. The entire process features symmetrical ring construction and precise arc positioning, completely solving the problems of large deviations, asymmetrical stress, and sinking of the cantilever end in irregular structures.

[0048] 2. Key innovative technology: The project adopts a freestanding, non-reinforced tiered grandstand, which eliminates the need for rebar installation and pre-reserved steel bars. This does not damage the semi-circular floor deck and the cantilever structure's load-bearing system, simplifying procedures, shortening the construction period, and improving the overall structural integrity.

[0049] 3. The cantilever structure is safe and controllable: The two-story cantilever roof adopts symmetrical hoisting, temporary tying and deflection pre-control technology, and the deformation of the cantilever end is controllable, which greatly improves the structural stability and safety.

[0050] 4. Integrated and collaborative construction throughout the entire process: from foundation pre-embedding, main steel structure, cantilevered roof, inclined columns, curtain wall, grandstand, rough decoration to fine decoration, the entire process is carried out in an interlocking manner, with close connection between the processes, shortening the overall construction period by more than 30%.

[0051] 5. Ultra-high curved ceiling is safe and reliable: The bottom-hanging and top-pulling two-way force-bearing system is suitable for semi-circular curved shapes, solving the problems of deformation and falling off of ultra-high (20m) and large-span (56m) curved ceilings, and meeting quality and safety standards.

[0052] 6. Standardized parameters throughout the entire process: A complete set of arc positioning, accuracy deviation, material specifications, and stress control parameters are developed for the semi-circular structure, ensuring that the construction quality is controllable throughout the entire process, with no leakage, no deformation, and no installation misalignment. Attached Figure Description

[0053] Figure 1 This is a flowchart illustrating the integrated construction method for the semi-circular cantilevered ultra-high, large-span auditorium described in this invention.

[0054] Figure 2 This is a schematic cross-sectional view of the semi-circular cantilevered ultra-high long-span auditorium described in this invention;

[0055] In the diagram: 1-Outer ring inclined column; 2-Curtain wall; 3-Grandstand; Detailed Implementation

[0056] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0057] Reference Figure 1 , 2 As shown, the integrated construction method for a semi-circular cantilevered ultra-high, large-span auditorium according to the present invention specifically includes the following processes:

[0058] Step 1: Construction of reinforced concrete base slab and precise pre-embedding of semi-circular embedded parts;

[0059] After the site is leveled and compacted, a C15 plain concrete subbase with a thickness of 100mm is poured, and the elevation deviation of the top surface of the subbase is ±10mm.

[0060] Arrange the semi-circular building axis in an arc shape, tie the HRB400E grade 16mm diameter reinforcing steel bars in the bottom slab, double-layer bidirectional arrangement with a spacing of 150mm, and a steel bar protective layer thickness of 40mm.

[0061] Precisely embed Q355B steel embedded parts for temporary support in the core area along the semi-circular radial direction. The steel plate is 20mm thick. It is fixed by three-sided welding of the arc-shaped positioning frame and the main reinforcement of the bottom plate. The radial arc deviation of the embedded parts is ≤2mm, the axial deviation is ≤3mm, and the elevation deviation is ≤2mm.

[0062] Pour a C35P6 waterproof reinforced concrete base slab with a thickness of 400mm. Vibrate and compact the concrete symmetrically in semi-circular sections. Keep the concrete moist and cured for ≥14 days until the concrete strength reaches 100% of the design strength.

[0063] Step 2: Construction of temporary support system for the semi-circular core area;

[0064] Using the radial embedded parts of the base plate as the foundation, a temporary steel support system for the core area is erected symmetrically along the semi-circular radial direction. The support columns are made of Q355B steel H-beams with dimensions of H300×200×10×14 (meaning H-beams with a section height of 300mm, a section width of 200mm, a web thickness of 10mm, and a flange thickness of 14mm). The columns are arranged in a radial arc shape with a verticality deviation of ≤1‰. The columns are arranged according to the stress points of the arc-shaped large-span steel beams with a standard spacing of 3m.

[0065] After the support system is erected, a preload is applied, with the preload load being 1.2 times the total construction load. The load is held for 24 hours. The support settlement is ≤5mm to eliminate inelastic deformation. After the overall flatness deviation of the arc is ≤3mm, the system is accepted.

[0066] Step 3: The first layer of semi-circular core large-span steel beams and outer ring inclined columns 1 are constructed simultaneously;

[0067] After the temporary support system passed the acceptance test, the first semi-circular core large-span steel beam and the outer ring inclined column 1 were hoisted in symmetrical sections along the semi-circle to achieve synchronous stress on the arc structure.

[0068] Among them, the semi-circular core large-span steel beam is made of Q355B steel and is an arc-shaped H-beam with dimensions of H1800×600×30×40 and a maximum span of 56m. It is arranged radially along the semi-circle, and the beam is arched at 1 / 500 of the span with an arch height of 112mm and an arc curvature deviation of ≤2mm.

[0069] Among them, the outer ring inclined column 1 of the first layer is a box-shaped arc inclined column with a cross-section of 400×400×16mm made of Q355B steel. It is arranged in a ring along the semi-circular outer ring, with an installation tilt angle deviation of ≤0.5° and a ring positioning deviation of ≤3mm.

[0070] The components are connected using M30 high-strength bolts of grade 10.9, and the joints are made of full penetration first-class welds. After the welds are completed, 100% ultrasonic non-destructive testing is performed. After passing the test, the whole structure forms a stable semi-circular steel frame.

[0071] Step 4: Construction of the first-floor roof steel auxiliary structure;

[0072] Based on the semi-circular steel frame, the following auxiliary structures were constructed simultaneously: a suspended corridor with a first-floor roof steel structure, a sunken courtyard with a first-floor roof steel structure, and a circular water ditch with a first-floor roof steel structure.

[0073] The main beams of the corridor, courtyard, and ditch are all made of Q355B steel H-beams with dimensions of H500×200×12×16. They are arranged along a semi-circular arc and connected to the main semi-circular steel frame by bolts and welding. The welds of the steel sections are secondary welds. The verticality deviation of the steel sections on the courtyard side wall is ≤2‰. The longitudinal slope of the ring ditch is 0.5%, and the ring drainage is unobstructed and free of water accumulation.

[0074] Step 5: Laying of steel truss floor decking and pouring of concrete;

[0075] TD6-90 type steel truss floor decking is laid on the first layer of semi-circular core large-span steel beam, cut and adapted along the arc. The truss reinforcement uses HRB400Φ8mm (meaning hot-rolled ribbed steel bars with a diameter of 8mm and a strength grade of 400MPa).

[0076] The steel truss floor deck is fixed to the semi-circular core large-span steel beam by welding Φ16×80mm (meaning diameter 16mm and length 80mm) studs, with a stud spacing of 300mm and denser arrangement at the arc-shaped end.

[0077] After tying the upper layer of reinforcing bars, pour C30 concrete with a thickness of 120mm and a surface flatness deviation of ≤3mm. Pour symmetrically along a semi-circle and keep it moist until the concrete strength reaches 75% of the design strength.

[0078] Step 6: The steel beams of the second-floor cantilevered roof and the suspended tiered grandstand 3 are constructed simultaneously;

[0079] The second-floor cantilever roof steel beams are hoisted in symmetrical sections along the semi-circular radial direction. Their material, specifications, and connection process are the same as those of the first-floor semi-circular core large-span steel beams. The cantilever section is 6m long, and temporary tie-downs are installed at the cantilever ends. The cantilever deflection is strictly controlled to be ≤1 / 800 of the span.

[0080] Simultaneously, a semi-circular reinforced concrete stepped grandstand 3 was constructed. Grandstand 3 adopted a placement construction process, with no rebar installation or pre-reserved rebar throughout the entire process. The specific construction method is as follows:

[0081] (1) Erect a semi-circular grandstand with a fixed arc formwork. No on-site rebar installation or pre-reserved rebar is required. The rebar skeleton of the grandstand is directly placed on the support base.

[0082] (2) Stand 3 is made of C30 cast-in-place concrete, with a step height of 160mm, a width of 350mm, a slab thickness of 100mm, and is equipped with HRB400EΦ8mm double-layer bidirectional steel bars with a spacing of 150mm;

[0083] (3) The formwork is supported by a disc-lock scaffold with a pole spacing of 0.9m×0.9m and a step distance of 1.5m. The deviation of the ring axis of the grandstand is ≤5mm and the elevation deviation is ±3mm.

[0084] Step 7: Construction of the cantilevered roof deck slab and refined shaping of the grandstand 3;

[0085] A steel truss floor slab of the same specification is laid on the steel beam of the cantilevered roof on the second floor. The cantilever section is fixed with dense studs and C30 concrete is poured. The construction process is the same as that of the steel truss floor slab of the bottom floor.

[0086] Simultaneously, the semi-circular stepped grandstand 3 underwent concrete finishing, straightening of the arc, sealing of construction joints, and moisturizing and curing for ≥7 days. The curvature, slope, and step size of grandstand 3 were finely adjusted, eliminating the need for subsequent steel reinforcement modifications and ensuring that the circular appearance and dimensions met the standards.

[0087] Step 8: Construction of the outer ring and courtyard curtain wall 2;

[0088] After the acceptance of the main semicircular steel structure is qualified, construct the outer ring curtain wall on the first floor and the sunken courtyard curtain wall;

[0089] Curtain wall 2 is arranged along the semicircular ring, adopting Q235B galvanized curved steel keels, with the annular radian deviation of the keel ≤ 2mm, the verticality deviation ≤ 2mm, and the spacing deviation ≤ 3mm; after the keel installation is completed, install the curved curtain wall panels, apply neutral silicone weather-resistant sealant, with a joint width of 15mm and a thickness of 5mm, and conduct a 2-hour continuous water spraying test after the construction is completed, which is qualified if there is no leakage at the annular closing part.

[0090] Step 9: The overhanging roof structure is constructed synchronously with the rough finishing of the first floor;

[0091] Construct the roof structural layer on the floor deck of the second-floor overhanging roof: 1.5mm thick polyurethane waterproof coating + 50mm thick extruded polystyrene board insulation layer + 60mm thick C20 fine aggregate concrete protective layer, and perform waterproof closing treatment at the overhanging end;

[0092] Synchronously carry out the rough finishing of the wall and floor of the semicircular hall on the first floor, the wall is leveled with 20mm thick cement mortar, the floor is poured with a 100mm thick concrete cushion, the surface flatness deviation ≤ 3mm, and the annular internal and external corners are straight.

[0093] Step 10: Fine finishing of the first and second floors and construction of the super-high curved ceiling;

[0094] After the construction of curtain wall 2 and the rough finishing are completed, carry out the fine finishing construction of the first and second floors;

[0095] The first-floor hall has a floor height ≥ 20m and a span ≥ 56m, and is integrally provided with a semicircular curved ceiling, which adopts a special construction process of hanging from below and pulling from above, as detailed below:

[0096] (1) Force-bearing system: The upper layer adopts Φ12 (diameter 12mm) hot-dip galvanized full-thread screw rods which are welded and fixed to the second-floor overhanging steel beams, and the lower layer is provided with Φ10 hot-dip galvanized reverse pull rods, which are symmetrically arranged along the semicircular ring to form a two-way force-bearing system, the spacing between the suspenders and the pull rods is ≤ 1200mm, and the distance to the wall is ≤ 1800mm;

[0097] (2) Curved keel system: U-type accessible light steel curved main keels are adopted, with a wall thickness ≥ 1.2mm and a spacing ≤ 1200mm, the spacing of the secondary keels is 600mm, the ceiling is adapted to the semicircular radian, and arching is set at 1 / 800 of the span;

[0098] (3) Reinforcement measures: When the length of the suspender exceeds 2500mm, additional annular steel structure reverse supports are provided, with a spacing ≤ 3600mm, which are arranged oppositely adjacent to each other to prevent deformation of the curved keel;

[0099] (4) The fine finishing of the curved wall and floor is completed synchronously, the squareness deviation of internal and external corners is ≤ 2mm, and the overall annular appearance is smooth and straight.

[0100] In this embodiment, preferably:

[0101] In step 3, the semi-circular core large-span steel beam and the outer ring inclined column 1 are hoisted in a ring-shaped symmetrical segment. During the hoisting process, the arc deformation and the deflection of the cantilever end are monitored in real time, and the deformation is controlled within ±3mm.

[0102] In step 6, the support base of the suspended tiered grandstand is treated with anti-corrosion before installation. After welding, two coats of anti-corrosion paint are applied. The steel reinforcement cage is directly placed and positioned along the semi-circle without the need for rebar installation or damage to the floor deck structure.

[0103] In step 10, before the construction of the bottom-hanging and top-pulling curved ceiling, a pull-out test is conducted on the threaded rods and tie rods. The bearing capacity is not less than 2.5 times the self-weight of the ceiling. The settlement and curvature deviation of the curved ceiling are monitored throughout the construction process.

[0104] The embodiments described above are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A fully integrated construction method for a semi-circular cantilevered, ultra-high, large-span auditorium, characterized in that: The process includes the following: Step 1: Construct the reinforced concrete base slab and embedded parts; Step 2: Construction of temporary support system in the core area; Step 3: The first layer of semi-circular core large-span steel beams and outer ring inclined columns (1) are constructed simultaneously; Step 4: Construction of the first-floor roof steel auxiliary structure; Step 5: Laying of steel truss floor decking and pouring of concrete; Step 6: The steel beams of the second-floor cantilevered roof and the suspended tiered grandstand (3) are constructed simultaneously; Step 7: Construction of the cantilevered roof deck and the refined shaping of the grandstand (3); Step 8: Curtain wall (2) construction; Step 9: The cantilevered roof structure is constructed simultaneously with the first-floor rough finishing; Step 10: Construction of the first and second floor interior decoration and ultra-high curved ceiling.

2. The integrated construction method for the entire process of a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, Step 1 includes: After leveling and compacting the site, a 100mm thick plain concrete foundation layer is poured. Following the semi-circular building axis, an arc-shaped layout is established, and HRB400E grade 16mm diameter reinforcing bars are tied to the base slab in a double-layer, bi-directional arrangement with a spacing of 150mm and a 40mm thick protective layer. Temporary support steel plates with a thickness of 20mm are precisely embedded along the semi-circular radial direction and fixed to the main reinforcing bars of the base slab on three sides using an arc-shaped positioning frame. A 400mm thick waterproof reinforced concrete base slab is poured, symmetrically vibrated and compacted along the semi-circular arc, and then cured with moisture.

3. The integrated construction method for the entire process of a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, Step 2 includes: Using the radial embedded parts of the base plate as the foundation, a temporary steel support system for the core area is erected symmetrically along a semi-circular radial direction. The support columns of the temporary support system are made of Q355B steel H-beams with dimensions of H300×200×10×14. The support columns are arranged in a radial arc shape, and the support columns are arranged according to the stress points of the semi-circular core large-span steel beam. After the temporary support system is erected, a preload is applied. The preload is 1.2 times the total construction load, held for 24 hours, and the support settlement is ≤5mm to eliminate inelastic deformation.

4. The integrated construction method for the entire process of a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, Step 3 includes: After the temporary support system is accepted, the first semi-circular core large-span steel beam and the outer ring inclined column (1) are hoisted in symmetrical sections along the semi-circle to achieve synchronous stress on the arc structure. The semi-circular core large-span steel beam is made of Q355B steel and is an arc H-beam with dimensions of H1800×600×30×40 and a maximum span of 56m. It is arranged radially along the semi-circle. The beam is arched at 1 / 500 of the span, with an arch height of 112mm and an arc deviation of ≤2mm. The first-layer outer ring inclined column (1) is a box-shaped arc inclined column with a cross-section of 400×400×16mm made of Q355B steel and is arranged in a ring along the outer circle of the semi-circle. The components are connected by high-strength bolts, and the nodes are made of full penetration first-class welds. After the welds are completed, ultrasonic non-destructive testing is carried out. After the test is qualified, a stable semi-circular steel frame is formed.

5. The integrated construction method for the entire process of a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, In step 4, the first-floor roof steel auxiliary structure includes a first-floor roof steel structure hanging corridor, a first-floor roof steel sunken courtyard, and a first-floor roof steel ring water ditch, all constructed simultaneously. Step 8 includes: the curtain wall (2) is arranged in a semi-circular ring and galvanized arc-shaped steel keel is used; after the keel is installed, the arc-shaped curtain wall panel is installed, neutral silicone weather-resistant sealant is applied, and a continuous water spray test is carried out after the construction is completed.

6. The integrated construction method for the entire process of a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, Step 5 includes: laying a steel truss floor deck on the first layer of semi-circular core large-span steel beam, cutting it along the arc to fit, and using hot-rolled ribbed steel bars with a diameter of 8mm and a strength grade of 400MPa for the truss reinforcement; the steel truss floor deck is fixed to the semi-circular core large-span steel beam by welding with studs, with a stud spacing of 300mm, and denser arrangement at the arc-shaped end; after binding the upper layer of reinforcement, pouring concrete with a thickness of 120mm, pouring symmetrically along the semi-circle, and keeping it moist for curing.

7. The integrated construction method for the entire process of a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, Step 6 includes: The second-floor cantilever roof steel beams are hoisted in symmetrical segments along the semi-circular radial direction. Their material, specifications, and connection process are the same as those of the first-floor semi-circular core large-span steel beams. Temporary tie-downs are set at the cantilever ends to strictly control the cantilever deflection to ≤1 / 800 of the span. Simultaneously, the first-floor semi-circular reinforced concrete stepped grandstand (3) is constructed. The grandstand (3) adopts a placement construction process with no rebar installation or pre-reserved rebar throughout the process. The specific construction method is as follows: The semi-circular grandstand is constructed using a fixed arc-shaped template. No on-site rebar installation or pre-reserved rebar is required. The rebar skeleton of the grandstand (3) is placed directly on the support base. The grandstand (3) is made of cast-in-place concrete with a step height of 160mm, a width of 350mm, a slab thickness of 100mm, and double-layer bidirectional rebar with a spacing of 150mm. The template is supported by a disc-lock scaffold with a pole spacing of 0.9m×0.9m and a step distance of 1.5m.

8. The integrated construction method for a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, Step 7 includes: On the steel beams of the cantilevered roof of the second floor, steel truss floor slabs of the same specification are laid. The cantilever section is fixed with densified studs and concrete is poured. The construction process is the same as that of the bottom steel truss floor slab. At the same time, the semi-circular stepped grandstand (3) is finished with concrete, straightened with arc, sealed with construction joints and moisturized. The curvature, slope and step size of the grandstand (3) are adjusted in detail.

9. The integrated construction method for a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, Step 9 includes: The roof structure layer is constructed on the second-floor cantilever roof slab: 1.5mm thick polyurethane waterproof coating + 50mm thick extruded polystyrene board insulation layer + 60mm thick C20 fine stone concrete protective layer, with waterproof finishing treatment at the cantilever end; at the same time, the rough finishing of the walls and floor of the first-floor semi-circular hall is constructed, with the walls leveled with cement mortar and the floor poured with a concrete slab, ensuring that the internal and external corners are straight.

10. The integrated construction method for the entire process of a semi-circular cantilevered ultra-high, large-span auditorium according to claim 1, characterized in that, In step 10, the entire first-floor lobby features a semi-circular arched ceiling, constructed using a specialized bottom-hanging and top-pulling construction technique, as detailed below: The upper layer is fixed to the second-layer cantilever steel beam by welding hot-dip galvanized threaded rods, and the lower layer is equipped with hot-dip galvanized reverse tie rods, which are symmetrically arranged along a semi-circular ring to form a two-way force system. The spacing between the hangers and tie rods is ≤1200mm, and the distance from the wall is ≤1800mm. Curved keel system: U-shaped light steel curved main keel with wall thickness ≥1.2mm and spacing ≤1200mm, secondary keel spacing 600mm, ceiling adapted to semi-circular arc, arched according to 1 / 800 of span; Reinforcement measures: When the length of the hanger exceeds 2500mm, add a ring-shaped steel structure counter-bracing with a spacing of ≤3600mm and set up adjacent to each other to prevent deformation of the arc-shaped keel; Simultaneously complete the fine decoration of curved walls and floors, control the deviation of squareness of inside and outside corners, and ensure that the overall circular appearance is smooth and straight.

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