BIM Application and Formwork Construction Technology of Suspended Inverted Frustum Concrete Structure

Abstract

The present invention discloses a BIM application and formwork construction technology method for a suspended inverted frustum-shaped concrete structure, which relates to the technical field of cast-in-place concrete pile construction. It includes BIM modeling, determining erection technical parameters, visual disclosure, formwork support system erection, formwork support system acceptance, steel bar fabrication and installation, concealed acceptance, and pouring and monitoring process steps. It simplifies the processing of complex suspended structure formwork, and the installation is in place at one time, improving the construction efficiency and ensuring the project quality; the gravity of the suspended structure is concentrated on 6 suspension columns and the ring beam, and the layout of the force-bearing vertical poles of the formwork support adopts the coordination of concentration and integrity to ensure the stability of the formwork; the suspension columns penetrate the entire space model, and the node steel bars are dense and complex. Partial binding and forming outside the formwork and then hoisting into the formwork are adopted to solve the problem of difficult binding of the inclined suspension column steel bars; self-compacting concrete is used to effectively solve the problems of difficult pouring and vibration of concrete in the narrow space with dense steel bars and thin inclined plates.

Description

Technical Field

[0001] The present invention relates to the technical field of cast-in-place concrete pile construction, and specifically to the BIM application and formwork construction process method of a suspended inverted frustum-shaped concrete structure. Background Technique

[0002] BIM is the abbreviation of Building Information Modeling. It integrates all relevant information of a building engineering project through three-dimensional digital technology, provides a detailed expression of the full-cycle information of the engineering project, is a direct application of digital visualization technology in building engineering, and warns and analyzes various problems in advance of the project, enabling all parties involved in the engineering project to understand and respond, and at the same time providing a solid foundation for collaborative work.

[0003] For the renovation and expansion project of Hunan Museum, through an international design bid, the design scheme of "Flourishing Dongting" by the world-famous architect Mr. Arata Isozaki was selected. The design concept includes reproducing the unearthed scene at a scale of 1:1 inside the museum, adopting a suspended inverted frustum-shaped, complex spatial concrete structure system, which is composed of obliquely suspended columns, special-shaped beams, and thin inclined plates intersecting and combining, with the bottom end suspended 4.85 m and the top end 17.75 m. In order to realize the design concept of the scene, our company adopted BIM technology, simplified the construction of the complex structure of the scene, and proposed a construction process method. Summary of the Invention

[0004] The purpose of the present invention is to provide a BIM application and formwork construction process method for a suspended inverted frustum-shaped concrete structure, so as to solve the problems of the construction of the suspended inverted frustum-shaped complex spatial concrete structure system in the above background technique, ensure the project quality, and reduce the project cost.

[0005] To achieve the above purpose, the present invention provides the following technical solution: The BIM application and formwork construction process method for a suspended inverted frustum-shaped concrete structure is as follows

[0006] S1 Use BIM software to model and convert two-dimensional plane drawings into three-dimensional solid models;

[0007] S2 Determine the erection technical parameters, make a three-dimensional steel bar model based on the three-dimensional model and the reinforcement information in the drawings, and establish a formwork installation model based on the three-dimensional structure model, requiring the formwork model to have accurate dimensions;

[0008] S3 Visualized disclosure: Based on the established three-dimensional solid model, make a simulated construction animation, vividly express the overall construction arrangement and key processes, and match the audio to explain the construction key points and related requirements to form a visualized disclosure video file;

[0009] S4 Erection of the formwork system, which requires layout lofting, stretching a line, strengthening fixation, compounding, and checking the accuracy;

[0010] S5 formwork support system acceptance, start the acceptance procedure;

[0011] S6 steel bar production and installation, process lap arrangement, hidden inspection and acceptance;

[0012] S7 concrete pouring, monitoring and maintenance.

[0013] Further: the software used in S1 is Revit software. During the modeling process, effective communication is maintained with the original designers. The complete model must be approved by the original designers to ensure that the model fully complies with the design intent; the steel bar arrangement, anchorage length and connection position comply with the requirements of the "G101" atlas. For special suspension column components, single body models and segmented models are established.

[0014] Further: S2 divides the model into blocks, and uses the software statistics function to perform block information statistics and optimization adjustments, and finally forms a detailed template blanking table, including detailed template processing schematics, dimensions, and quantity information. According to the BIM three-dimensional model, the support pole layout is carried out, and the pole plane layout diagram is drawn using CAD software; the formwork force is verified for the load concentration points and general load points, and finally the basic parameters such as the vertical and horizontal spacing and step distance of the poles in different areas are determined. If the bottom of the formwork is a floor slab, the same formwork is set up on the lower floor to transfer the load to the foundation slab. The positions of the upper and lower poles must be consistent. According to the requirements of the specifications, the parameters of other structural measures such as the horizontal and vertical scissor support arrangement of the formwork and the setting of wall connections are determined.

[0015] Further: the S3 establishes a three-dimensional model of the bracket according to the final determined detailed parameters of the bracket erection, further verifies whether the bracket can meet the installation requirements of the suspended structure modeling template, accurately positions and heights each pole, and intuitively displays the bracket erection to form a visual briefing video file; conducts detailed briefings to management personnel and professional work teams, and hands over all BIM model results, pole positioning and height, template cutting table and other detailed data to on-site management personnel and labor workers as a basis for directing on-site construction, guiding labor personnel's specific operations and quality inspections.

[0016] Further: S4 specifically includes the following:

[0017] 1) Before the support is erected, the edge lines of the control positioning components such as the hanging column, horizontal support beam, and symmetry axis are popped up on the -9.6m floor surface. According to the plan layout of the support poles, the poles are arranged and set out on site. A 5*5 pole matrix is ​​set for the hanging column 1, a 3*3 pole matrix is ​​set for the hanging column 2, and a 300mm*600mm spacing pole reinforcement belt is set along the wall panel;

[0018] 2), When erecting the vertical poles, it is required to pull a straight line. The poles should be horizontal and vertical. The position can be slightly adjusted according to the specific site conditions, but the total number of vertical poles shall not be less than the quantity shown in the vertical pole layout plan;

[0019] 3), Referring to the structural beam drawing of the supporting floor, for the vertical poles whose positions are not at the structural beams, a full-length channel steel must be added at the bottom of the vertical poles, and the length is the same as the spacing of the structural beams. At the post-cast strip, an I-beam must be padded at the bottom of the vertical poles. When the formwork support is erected on the negative first floor slab, it is necessary to erect the corresponding support frames in the same area of the negative second floor and negative third floor according to the positions of the vertical poles to transfer the construction load to the basement floor slab;

[0020] 4), The horizontal and vertical scissors braces are erected synchronously with the scaffold. According to the acceptance procedure, complete the erection of the support;

[0021] 5), Before formwork installation, conduct lofting and rechecking, and hang control lines at the corresponding positions; according to the formwork cutting list, process the formwork;

[0022] 6), During the installation process, according to the shape, size and positioning information provided by the formwork BIM model, check the positioning and reinforcement of the formwork at any time to ensure the accuracy of the position, slope, splicing, bending position and angle of the formwork;

[0023] 7), The external formwork of the suspended structure is installed to the top in one go. The internal formwork is first installed to the elevation of 2.669m, and the second installation is to the top. After the reinforcement installation at the corresponding positions is completed and accepted, the internal formwork installation is carried out.

[0024] Furthermore: After the first step of the support erection is completed at the construction site in S5, conduct the first erection acceptance; after passing the acceptance of the first step of the scaffold, conduct an intermediate acceptance every 4 steps of the middle section of the support; after the support erection is completed, conduct the final acceptance of the support before pouring concrete; conduct the quality acceptance of the materials used; conduct the acceptance of the construction standards: The acceptance content includes whether the quality of the turnover materials such as steel pipes and fasteners used on site meets the requirements; confirm whether the spacing of the vertical and horizontal poles, the setting of scissors braces, safety protection, connecting wall members and other structural measures of the on-site support erection meet the requirements of the special plan; whether the tightening torque of the fasteners meets the requirements, etc.

[0025] Furthermore: The S6 suspension structure is constructed in two stages. In the first stage, the concrete is poured to the top of the beam at an elevation of 2.669 m. In the second stage, the concrete is poured to an elevation of 8.10 m. While erecting the formwork support for the suspension structure, the concrete for the surrounding structure is poured first, and construction joints are set around. That is, the surrounding structure is constructed to an elevation of 8.10 m, including the structures at elevations of -4.8 m, -0.15 m, 2.669 m, and 4.40 m. The steel bar fabricators conduct handover inspections on the formwork installation dimensions, and review whether the steel bar dimensions, bending positions, and angles in the steel bar model are consistent with the site conditions. After confirmation, a steel bar cutting list is prepared based on the model information, and the steel bars for the beams, slabs, and columns are fabricated. The lower part of the hoist column steel bars is tied into shape outside the formwork at one time, and then hoisted as a whole into the formwork by a tower crane. The upper part is installed inside the formwork. The external geometric dimensions of the hoist column steel cage are strictly reviewed, and a string is pulled to review the straightness, corner positions, and corner angles, ensuring the steel bar cover thickness. Multiple-point lifting is adopted to prevent plastic deformation of the steel cage during hoisting, which may affect the installation. The steel bars of the wall panels and beams are installed on-site inside the formwork in two stages. The first stage is installed to an elevation of 2.669 m. After the concrete is poured, it is then installed to the top of the suspension structure. The construction process requires multiple checks.

[0026] Furthermore: The S7 specifically includes the following:

[0027] 1) To solve the problems of dense steel bars on-site, difficult concrete pouring and vibration, self-compacting concrete is used for construction. Before construction, the concrete mixing plant designs the mix proportion and conducts trial mixing. On the premise of meeting the requirements, the optimal mix proportion is determined. The mixture is centrally mixed and controlled by a computer system to ensure stable quality.

[0028] 2) For on-site concrete construction, the pouring method of dividing into rings is adopted. According to the position of the beam, the number of rings is divided according to a height of 800 mm or 1000 mm. After all the concrete in each ring is poured, the pouring of the next ring of concrete is started. The first concrete pouring reaches an elevation of 2.669 m, and the second concrete pouring reaches the top of the suspension structure.

[0029] 3) At the beam-column joints, the steel bars are very dense. To ensure the compactness of the concrete, an external vibrator is used to vibrate this part appropriately outside the formwork.

[0030] 4) After the concrete of the suspension structure is poured, the internal formwork should be moist-cured with the formwork for 3 days before it can be removed. The exposed concrete surface after the removal of the internal formwork must be covered with geotextile, and the geotextile should be kept moist.

[0031] 5) When the concrete poured in the second stage reaches 28 days of age and the compressive strength of the concrete test blocks under the same conditions meets the specification requirements, the formwork and support of the suspension structure can be removed.

[0032] 6) Observation points are set at the suspension structure brackets at the suspension columns and at the wall panels, and the reference points are set on the surrounding structural columns. The initial values are measured before the concrete pouring, and the observation points are monitored in real time during the concrete pouring.

[0033] 7) During the concrete pouring, the formwork support is monitored in real time. The settlement value is monitored by a level and the deformation value is monitored by a theodolite. If the warning value is exceeded, the concrete pouring is immediately suspended, the cause is found, and corresponding measures are taken.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] 1. By using BIM technology to establish a suspension structure model, setting up formwork and supports, and conducting three-dimensional visualization disclosure, the processing of complex suspension structure formwork is simplified, and the installation is in place at one time, improving the construction efficiency and ensuring the project quality.

[0036] 2. The gravity of the suspension structure is concentrated on 6 suspension columns and the ring beam. The layout of the load-bearing vertical poles of the formwork support adopts concentration and overall coordination, ensuring the stability of the formwork.

[0037] 3. The suspension columns penetrate the entire space model, and the node steel bars are dense and complex. By using partial out-of-formwork binding and forming and then hoisting them into the formwork, the problem of difficult binding of the steel bars of the inclined suspension columns is solved.

[0038] 4. By using self-compacting concrete, the problems of difficult pouring and vibrating of concrete in the narrow space with dense steel bars and thin inclined plates are effectively solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic flow chart of the present invention;

[0040] Figure 2 It is a schematic diagram of the wall panel and suspension column model of the suspension structure;

[0041] Figure 3 It is a schematic diagram of the overall model of the suspension structure;

[0042] Figure 4 It is a schematic diagram of the overall three-dimensional model of the steel bars;

[0043] Figure 5 It is a schematic diagram of the three-dimensional model of the steel bars of the suspension column;

[0044] Figure 6 It is a schematic diagram of the three-dimensional model of the formwork;

[0045] Figure 7 It is a partial schematic diagram of the plane layout of the vertical poles of the support;

[0046] Figure 8 It is a schematic diagram of the steel pipe fastener support model;

[0047] Figure 9 It is a schematic sectional view of the support layout;

[0048] Figure 10 It is a schematic diagram of formwork installation simulation;

[0049] Figure 11 It is a schematic diagram of concrete pouring in rings;

[0050] Figure 12 It is a schematic diagram of the layout of support monitoring points. Specific implementation manners

[0051] Next, the accompanying drawings in the embodiments of the present invention will be combined. The present invention will be described below based on the embodiments. However, it is worth noting that the present invention is not limited to these embodiments. In the following detailed description of the present invention, some specific details are described in detail. However, for the parts that are not described in detail, those skilled in the art can also fully understand the present invention.

[0052] In addition, those of ordinary skill in the art should understand that the provided drawings are only for illustrating the purpose, features, and advantages of the present invention, and the drawings are not actually drawn to scale.

[0053] At the same time, unless the context clearly requires, the words such as "including" and "comprising" in the whole specification and claims should be interpreted as the meaning of including rather than exclusive or exhaustive meaning; that is, the meaning of "including but not limited to".

[0054] Please refer to Figures 1-12 , the present invention provides a technical solution:

[0055] Including S1: Modeling with BIM software to convert two-dimensional plane drawings into three-dimensional solid models. The software used is Revit software. During the modeling process, maintain effective communication with the original designers. The complete model needs to be recognized by the original designers to ensure that the model fully conforms to the design intent; the arrangement of steel bars, anchorage length, and connection positions comply with the requirements of the "G101" atlas. For special suspension column members, establish single-body models and segmented models as shown in the appendix Figures 2-6 .

[0056] S2: Determine the erection technical parameters, as shown in the appendix Figure 7According to the reinforcement information in the 3D model and drawings, a 3D reinforcement model is made. Based on the structural 3D model, a formwork installation model is established. It is required that the formwork model dimensions are accurate. The model is divided into blocks, and the software statistical function is used to conduct block information statistics and optimization adjustments. Finally, a detailed formwork cutting list is formed, including detailed formwork processing sketches, dimensions, and quantity information. According to the BIM 3D model, the layout of the support vertical poles is carried out, and the CAD software is used to draw the plan layout diagram of the vertical poles; the force checking calculations of the formwork support are carried out separately for the load concentration areas and general load areas, and finally the basic parameters such as the longitudinal and transverse spacing and step distance of the vertical poles in different areas are determined. If the bottom of the formwork support is the floor slab, the same formwork support is erected on the lower floor to transfer the load to the foundation slab. The positions of the upper and lower layer vertical poles need to be consistent. According to the specification requirements, other construction measure parameters such as the layout of the horizontal and vertical scissors braces and the setting of the connecting wall members of the formwork support are determined.

[0057] S3 Visualized disclosure. Based on the established 3D solid model as attached Figure 8 , make a simulated construction animation to vividly express the overall construction arrangement and key processes, and match the audio to explain the construction key points and related requirements to form a visualized disclosure video file; S3 Based on the finally determined detailed erection parameters of the support, establish a 3D support model to further verify whether the support can meet the formwork installation requirements of the hanging structure shape, accurately position and height each vertical pole, and visually display the support erection to form a visualized disclosure video file; conduct a detailed disclosure to the management personnel and personnel of each professional operation team, and hand over all the BIM model results, the positioning and height of the vertical poles, the formwork cutting list and other detailed data to the on-site management personnel and labor operators as the basis for guiding the on-site construction, guiding the specific operations of the laborers and quality inspection.

[0058] S4 Formwork system erection as attached Figure 9 and 10 , it is necessary to arrange for lofting, pull through lines, strengthen fixation, compound, and proofread the accuracy; specifically include the following:

[0059] 1). Before the erection of the support, the sidelines of the control positioning components such as the suspension columns, horizontal support beams, and symmetry axes are popped on the -9.6m floor slab surface. According to the plan layout diagram of the support vertical poles, conduct the layout lofting of the vertical poles on-site. A 5*5 vertical pole matrix is set for the suspension column 1, a 3*3 vertical pole matrix is set for the suspension column 2, and a vertical pole strengthening belt with a spacing of 300mm*600mm is set along the wall panel.

[0060] 2). When erecting the vertical poles, it is required to pull through lines, and the members are horizontal and vertical. The position can be slightly adjusted according to the specific on-site situation, but the total number of vertical poles shall not be less than the number in the plan layout diagram of the vertical poles;

[0061] 3). For the support floor structural beam diagram, where the position of the vertical support poles is not at the structural beam, a full-length channel steel must be added at the bottom of the vertical poles, with a length equal to the spacing of the structural beams. At the post-cast strip, an I-beam must be padded at the bottom of the vertical poles. When the formwork support is erected on the negative first floor slab, the corresponding support frames should be erected in the same area on the negative second and third floors according to the position of the vertical poles to transfer the construction load to the basement floor slab;

[0062] 4). The horizontal and vertical scissors braces are erected synchronously with the formwork support. According to the acceptance procedure, the erection of the support is completed;

[0063] 5). Before formwork installation, lofting and rechecking are carried out, and control lines are hung at the corresponding positions; according to the formwork cutting list, formwork processing is carried out;

[0064] 6). During the installation process, according to the shape, size, and positioning information provided by the formwork BIM model, the positioning and reinforcement of the formwork are checked at any time to ensure the accuracy of the position, slope, splicing, bending position, and angle of the formwork;

[0065] 7). The external formwork of the hanging structure is installed in one go to the top to form a shape, and the internal formwork is first installed to the elevation of 2.669m and then installed to the top for the second time. After the reinforcement installation at the corresponding positions is completed and accepted, the installation of the internal formwork is carried out.

[0066] For the acceptance of the S5 formwork support system, the acceptance procedure is initiated. After the first step of the support erection is completed at the construction site, the first erection acceptance is carried out; after passing the acceptance of the first step of the formwork, an intermediate acceptance is carried out every 4 steps of the erection of the middle section of the support; after the support erection is completed, the final acceptance of the support is carried out before pouring concrete; the acceptance content includes whether the quality of the turnover materials such as steel pipes and fasteners used on site meets the requirements; it is confirmed whether the spacing of the vertical and horizontal poles of the on-site support erection, the setting of scissors braces, safety protection, connecting wall members, and other structural measures meet the requirements of the special plan; whether the tightening torque of the fasteners meets the requirements, etc.

[0067] S6 Steel bar fabrication and installation, process lap arrangement, and concealed acceptance;

[0068] The overall construction of the S6 suspension structure is carried out in two stages. The first stage of concrete pouring reaches the top of the beam at an elevation of 2.669 m, and the second stage of concrete pouring reaches an elevation of 8.10 m. While erecting the formwork support of the suspension structure, the concrete of the surrounding structure is poured first, and construction joints are set around. That is, the surrounding structure is constructed to an elevation of 8.10 m, including the structures at elevations of -4.8 m, -0.15 m, 2.669 m, and 4.40 m. The steel bar fabricators conduct handover inspections on the formwork installation dimensions, and review whether the steel bar dimensions, bending positions, and angles in the steel bar model are consistent with the site. After confirmation, a steel bar cutting list is prepared based on the model information, and the steel bars for beams, slabs, and columns are fabricated. The lower part of the hoist column steel bars is tied into shape at one time outside the formwork, and is hoisted into the formwork as a whole by a tower crane. The upper part is installed inside the formwork. The appearance geometric dimensions of the hoist column steel cage are strictly reviewed, and a straight line is pulled through to review the straightness, corner positions, and corner angles to ensure the steel bar protection layer thickness. Multiple-point lifting is adopted to prevent plastic deformation of the steel cage during hoisting and affect the installation. The steel bars of the wall panel and the beam are installed on-site inside the formwork in two stages. The first stage is installed to an elevation of 2.669 m. After the concrete is poured, it is installed to the top of the suspension structure.

[0069] The concrete pouring, monitoring, and curing of S7 are as attached Figure 11 and 12 Specifically, it includes the following:

[0070] 1) To solve the problems of dense steel bars on-site, difficult concrete pouring and vibration, self-compacting concrete is used for construction. Before construction, the concrete mixing plant conducts mix proportion design and trial mixing. On the premise of meeting the requirements, the optimal mix proportion is determined. The mixture is centrally mixed and controlled by a computer system to ensure stable quality;

[0071] 2) For on-site concrete construction, the method of pouring in circles is adopted. According to the position of the beam, the number of circles is divided according to a height of 800 mm or 1000 mm. After all the concrete in each circle is poured, the pouring of the next circle of concrete begins. The first stage of concrete pouring reaches an elevation of 2.669 m, and the second stage of concrete pouring reaches the top of the suspension structure;

[0072] 3) At the beam-column joints, the steel bars are very dense. To ensure the compactness of the concrete, an external vibrator is used to vibrate this part appropriately outside the formwork;

[0073] 4) After the concrete of the suspension structure is poured, the internal formwork should be maintained with moist curing for 3 days before it can be removed. The exposed concrete surface after the removal of the internal formwork must be covered with geotextiles and kept moist;

[0074] 5) When the concrete poured in the second stage reaches 28 days of age and the compressive strength of the concrete test blocks under the same conditions meets the specification requirements, the formwork and support of the suspension structure can be removed;

[0075] 6) Observation points are set at the suspension structure brackets at the suspension columns and at the wall panels, and the reference points are set on the surrounding structural columns. The initial values are measured before the concrete pouring, and during the concrete pouring, the observation points are monitored in real time.

[0076] 7) During the concrete pouring, the formwork support is monitored in real time. The settlement value is monitored by a level and the deformation value is monitored by a theodolite. If the warning value is exceeded, the concrete pouring shall be immediately suspended, the cause shall be found, and corresponding measures shall be taken.

[0077] For all building materials such as steel bars and concrete, and turnover materials such as steel pipes and fasteners, the relevant quality certification materials of the manufacturers must be complete. Sampling on-site shall be witnessed batch by batch, and only after passing the inspection can they be used for on-site construction.

[0078] The materials are stacked on-site with elevation, and the stacking area shall not accumulate water. In case of necessity, rain-proof covering shall be carried out.

[0079] The mud content of the coarse and fine aggregates of concrete shall be strictly controlled, and the maximum particle size of the coarse aggregate shall not exceed the standard. Before the concrete mixing, the water content of the coarse and fine aggregates shall be detected in real time to ensure the accuracy of the water-cement ratio of the concrete.

[0080] On-site construction shall be tracked and inspected to ensure that the erection of the formwork support meets the requirements of the special construction plan, and the process control shall be strictly carried out.

[0081] Through the vivid display of the BIM model of the suspension structure, it helps the management personnel and operators to understand the plane drawings more accurately and recheck the accuracy of the formwork installation in real time.

[0082] According to the model and drawings, prepare the steel bar cutting list. After the main steel bars of the beams and columns are fabricated, recheck the dimensions, bending positions and angles of the formed main steel bars. The steel cage of the suspension column is tied outside the formwork, and the external dimensions of the steel cage are rechecked to ensure that the steel cage can be installed smoothly and meet the thickness of the protective layer. After the installation of the steel cage of the suspension column is completed, the protective layer pads are inserted into the formwork to play a role in fixing the steel cage.

[0083] The optimal mix ratio determined after the concrete trial mix is centrally produced by the concrete mixing plant. The mixing plant strictly controls the quality of raw materials such as cement, sand and gravel, and detects the water content of sand and gravel in real time to ensure the accuracy of the mix ratio. Sands and gravel with excessive mud content are strictly prohibited from being used.

[0084] The whole process of concrete feeding and mixing is accurately controlled by a computer to ensure reliable quality. The continuous mixing time of the concrete is 60s - 90s, and it is transported by a self-unloading concrete mixer truck. To prevent segregation during transportation, the concrete mixer truck must rotate slowly.

[0085]

[0086]

[0087] ​​Each concrete placement must be carried out continuously without cold joints. Strictly control the time from concrete discharge to pouring into the formwork. It is strictly prohibited to use concrete that has already started to set for pouring.

[0088] For the areas where steel bars are dense, such as beam-column joints, proper vibration shall be carried out to ensure that the concrete is filled densely. Prevent the cast concrete from being directly exposed to sunlight, and timely take measures to cover and shade it. Do not remove the inner formwork prematurely to prevent the concrete from chipping at the edges and corners. Adopt geotextile for moist curing, always ensure the geotextile is in a moist state, and the curing period shall not be less than 14 days. The formwork support can only be removed after the concrete of the suspended structure reaches 28 days of age.

[0089] Adopt BIM technology to establish a model of the suspended inverted frustum-shaped concrete structure. Design the support layout based on the model, and determine specific parameters such as the spacing of vertical poles through bearing capacity checking. Establish models for the formwork, support, and steel bars respectively, optimize the formwork block division, accurately determine the erection height of each vertical pole and the steel bar arrangement, obtain detailed formwork dimensions and positioning information, and form a formwork cutting list. Conduct three-dimensional visualization disclosure, use the model information as the main basis for on-site construction, and simplify the processing, positioning, and installation of formwork for complex structures.

[0090] The gravity of the suspended structure is concentrated on 6 suspension columns and the ring beam. The layout of the load-bearing vertical poles of the formwork support determines a unified modulus, and the spacing is in a multiple relationship. Optimize the overlap and interpenetration of each sub-project. The external formwork of the structure is installed in one piece, and the internal formwork is installed in two sections in sequence to solve the contradictions between formwork installation, steel bar installation, and concrete pouring. Select self-compacting concrete, which effectively solves the problems of difficult pouring and vibration of the thin inclined slab concrete caused by dense steel bars.

[0091] The adoption of BIM modeling enables construction personnel to organize on-site operations more intuitively, quickly, and accurately, avoids the phenomenon of groping during construction, reduces the construction difficulty, and reduces the rework caused by the unclear understanding of the design intention.

[0092] The traditional construction method of concrete structures has a certain degree of blindness, especially for three-dimensional special-shaped structures in space. Simply relying on two-dimensional plane drawings for construction, different construction personnel have different levels of spatial imagination ability, resulting in the phenomenon of "feeling the way as one goes" and tentative construction during the construction process. When construction errors occur, they cannot be discovered in time, or it is impossible to predict what problems will occur, leading to uncontrollability of the construction period and quality.

[0093] Effective measures are taken in all aspects of planning and construction to make the construction objectives of the suspension structure clear, vivid, and highly controllable. By comparing the 3D model with the on-site construction situation, everything is clearly visible, and the construction results can be quickly and accurately checked. The process connections are reasonably arranged. The external formwork is installed and formed at one time, the steel cage of the suspension column is hoisted as a whole, and the self-compacting concrete is poured in batches, effectively reducing the construction difficulty, improving the work efficiency, and accelerating the construction progress.

[0094] Although the embodiments of this patent have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of this patent. All non-substantive creations made on the basis of these embodiments will be regarded as tampering with or plagiarizing this patent and should be protected by law.

Claims

1. Construction technology method for formwork support of suspended inverted frustum-shaped concrete structure, characterized in that: S1. Use BIM software to model and convert two-dimensional plane drawings into three-dimensional solid models; S2. Determine the erection technical parameters. Based on the three-dimensional model and the reinforcement bar information in the drawings, fabricate three-dimensional reinforcement bar models. Based on the structural three-dimensional model, establish formwork installation models, requiring accurate formwork model dimensions; S3. Visual disclosure. Based on the established three-dimensional solid model, produce simulated construction animations, vividly express the overall construction arrangement and key processes, and accompany with audio explanations of construction key points and related requirements to form a visual disclosure video file; S4. Erection of the formwork system, which requires layout lofting, stretching lines, strengthening fixation, compounding, and checking accuracy, specifically including the following: 1). Before the erection of the support, control the side lines of the positioning components, conduct lofting of the erection of the vertical poles according to the vertical pole layout plan of the support. Set a 5*5 vertical pole matrix for suspension column 1 and a 3*3 vertical pole matrix for suspension column 2. Set a vertical pole strengthening belt with a spacing of 300mm*600mm along the wall panel; 2). When erecting the vertical poles, it is required to stretch lines so that the members are horizontal and vertical; 3). Where the position of the support vertical poles is not at the structural beam, a full-length channel steel must be added at the bottom of the vertical poles, with a length equal to the spacing of the structural beams. At the bottom of the vertical poles in the post-cast strip area, an I-beam must be padded; 4). Install the horizontal and vertical scissor braces synchronously with the scaffold. According to the acceptance procedure, complete the erection of the support; 5). Before formwork installation, conduct lofting and rechecking, hang control lines at the corresponding positions, and process the formwork according to the formwork cutting list; 6). Check the positioning and reinforcement of the formwork at any time to ensure the accuracy of the position, slope, splicing, bending position, and angle of the formwork; 7). The external formwork of the suspended structure is installed in one go to the top for forming. The internal formwork is first installed to a height of 2.669m, and the second installation is to the top. After the reinforcement installation at the corresponding positions is completed and accepted, the internal formwork installation is carried out; S5. Acceptance of the formwork support system, start the acceptance procedure; S6. Fabrication and installation of reinforcement bars, arrangement of process lap joints, and concealed acceptance; S7. Concrete pouring, monitoring, and curing.

2. The formwork construction process method of the hanging inverted frustum-shaped concrete structure according to claim 1, characterized in that: The software used in S1 is Revit software. During the modeling process, communicate to ensure that the model fully conforms to the design intention; the reinforcement bar layout, anchorage length, and connection position comply with the requirements of the atlas. For special suspension column members, establish single-body models and sectional models.

3. The formwork construction process method of the hanging inverted frustum-shaped concrete structure according to claim 1, characterized in that: S2 includes dividing the model into blocks, using the software statistical function to conduct block information statistics and optimization adjustments, finally forming a detailed formwork cutting list, arranging the layout of the support vertical poles, and using CAD software to draw the vertical pole layout plan; conduct force calculations for the formwork support at the load concentration areas and general load areas respectively to determine the basic parameters, maintain consistency, and determine the parameters for the layout of the horizontal and vertical scissor braces and the settings of the connecting wall members of the formwork support.

4. The formwork construction process method for the suspended inverted frustum-shaped concrete structure according to claim 1, characterized in that: S3 includes establishing a three-dimensional model of the support based on the finally determined detailed erection parameters of the support, conducting repeated verification to form a visual file; conduct detailed disclosure to the management personnel and personnel of each professional operation team.

5. The formwork construction process method for the suspended inverted frustum-shaped concrete structure according to claim 1, characterized in that: After the first - step scaffold erection is completed at the construction site in S5, the first erection acceptance is carried out; for every 4 - step erection of the middle section of the scaffold, an intermediate acceptance is carried out; after the scaffold erection is completed, the final scaffold acceptance is carried out before pouring concrete; the quality of the used materials is accepted; and the construction standards are accepted.

6. The formwork construction process method for the suspended inverted frustum-shaped concrete structure according to claim 1, characterized in that: S6 includes constructing the suspension structure in two stages. For the first stage, the concrete is poured to the top of the beam at an elevation of 2.669m, and for the second stage, the concrete is poured to an elevation of 8.10m. The steel - bar fabricators conduct handover inspections on the template installation dimensions, fabricate the steel bars for the beams, slabs, and columns. The lower part of the hanger - column steel bars is formed by one - time binding outside the template, and the upper part is installed inside the template. The steel bars of the wall panels and beams are installed on - site inside the template in two stages. The first - stage installation is up to an elevation of 2.669m. After the concrete is poured, the installation is continued up to the top of the suspension structure. The construction process requires multiple checks.

7. The formwork construction process method for the suspended inverted frustum-shaped concrete structure according to claim 1, characterized in that: S7 specifically includes the following: 1) Self - compacting concrete is used for construction. The concrete mixing plant designs the mix ratio to determine the optimal mix ratio to ensure stable quality. 2) The construction is carried out by the method of pouring in circles. According to the position of the beam, the number of circles is divided according to a height of 800mm or 1000mm. After each circle is completely poured, the pouring of the next circle of concrete begins. The first - stage concrete is poured to an elevation of 2.669m, and the second - stage concrete is poured to the top of the suspension structure. 3) At the beam - column joints, external vibrators are used to vibrate the beam - column joints moderately outside the template. 4) After the concrete of the suspension structure is poured, the internal formwork should be moist - cured with the formwork for 3 days before it can be removed. 5) When the concrete poured in the second stage reaches 28 - day age and the compressive strength of the concrete test blocks under the same conditions meets the specification requirements, the formwork and scaffold of the suspension structure can be removed. 6) Observation points are set at the hanger - column and wall - panel positions of the suspension - structure scaffold, and the observation points are monitored in real - time. 7) When pouring concrete, the formwork and scaffold are monitored in real - time. A level is used to monitor the settlement value, and a theodolite is used to monitor the deformation value. If the values exceed the warning values, the concrete pouring is immediately suspended, the reasons are found, and corresponding measures are taken.

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