Large-span curved curtain wall column cantilever structure system and installation method thereof

Abstract

The present application relates to the technical field of structural engineering, in particular to a large-span curved curtain wall dense column cantilever structure system and its installation method. The curved curtain wall cantilever structure system comprises a box-type dense column, which is sequentially connected and installed with an arc-shaped steel beam, a roof steel structure and a cantilever steel platform. Based on the installation method of the structure system, the sectional installation precision of the arc-shaped box-type steel beam is improved, and the problems of mutual penetration of the L-shaped curtain wall column nodes of the arc-shaped box-type steel beam in the structure system and installation precision control are solved.

Description

Technical Field

[0001] This invention relates to the field of structural engineering technology, specifically to a large-span curved curtain wall dense column cantilever structure system and its installation method. Background Technology

[0002] With the continuous development of economic life, people have increasingly higher requirements for the steel structure of curtain wall buildings. The shape and structural system of curtain walls are becoming more and more complex, which not only places higher demands on the structural system, component design, load-bearing capacity of connection nodes and building appearance, but also on the construction and installation precision and the structural stress performance after construction. The supporting steel structure of curtain walls is diverse and ever-changing. From the perspective of stress mechanism, it can be divided into three types: rigid frame structure, truss structure and prestressed cable rod structure. In the application of supporting steel structure for large-span curved curtain walls, the supporting steel structure often needs to have a large overall stiffness to resist horizontal and vertical loads. At the same time, its structural system should be lightweight, have a wide variety of forms, high transparency, and strong artistic expression.

[0003] The curved curtain wall supporting cantilever structure system boasts an aesthetically pleasing appearance. It employs a rigid frame structure system with high overall stiffness and strong resistance to deformation. The curved curtain wall facade features a box-shaped, closely spaced column structure, with the lower ends of the box columns reliably and rigidly connected to the ground structural layer. At elevations of 18.28 meters and 22 meters, curved box-shaped steel beams are rigidly connected to the main building structure. A 2.5-meter cantilevered concrete floor steel platform is located at the 18.28-meter elevation, and a roof steel structure with a cantilever of at least 12 meters is located at elevations of 22 to 24 meters. This results in complex stress distribution within the curved curtain wall supporting cantilever structure system, making the design of the 18.28-meter curved box beam node extremely challenging.

[0004] Patent application CN 217150807 U discloses a curved curtain wall support structure, comprising: at least one main body; multiple pre-embedded connecting components, which are spaced apart and installed on the main body; a curtain wall support frame, installed on the pre-embedded connecting components; and a curtain wall panel, which is installed on the curtain wall support frame and extends along the distribution direction of the pre-embedded connecting components. This solution solves the technical problem of single-assembly curtain walls in the prior art and improves the overall stability of the curtain wall. However, the curved curtain wall structure of this prior art is not improved, and the stress state of the structure after installation is inconsistent, and the installation accuracy of the support structure cannot be effectively controlled. Summary of the Invention

[0005] Based on the shortcomings of the aforementioned background technology, this invention addresses the problems of unstable structural mechanical properties of existing curved curtain walls and the inability to effectively control the installation accuracy of curved curtain walls. The aim is to provide a large-span curved curtain wall dense column cantilever structure system and its installation method, so that the stress state of the curved curtain wall structure is consistent and its installation accuracy is effectively controlled.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0007] A large-span curved curtain wall cantilever structure system includes box-shaped columns. The box-shaped columns are connected and installed with curved steel beams, roof steel structures, and cantilever steel platforms. The box-shaped columns include multiple lower curtain wall columns and upper curtain wall columns. The curved steel beams are horizontally located at the upper ends of the lower curtain wall columns. The roof steel structures are connected to the upper ends of the curved steel beams through the upper curtain wall columns. The cantilever steel platforms are horizontally located on the inner side of the curved steel beams.

[0008] As a further improvement of the present invention, the installation method includes the following steps:

[0009] Step 1: Locate and pre-embed the lower curtain wall column;

[0010] Step 2: Install the curved steel beam. The curved steel beam and the box-type close-column are rigidly eccentrically connected: the curved steel beam is evenly divided into multiple segments, and each segment of the curved steel beam is provided with a connecting L-shaped curtain wall column node. The L-shaped curtain wall column node makes the curtain wall load act eccentrically on the outside of the curved steel beam.

[0011] Step 3: Measurement and welding of the curved steel beams. Measurement points are set at the left and right ends of each curved steel beam segment and at the upper and lower curtain wall column nodes in Step 2. The welding of multiple curved steel beam segments adopts a correction welding process that combines welding and measurement.

[0012] Step four: Weld the joints. The installation of the box-shaped dense columns and the arc-shaped steel beams is carried out synchronously from both ends to the middle, and the welding work is carried out at the joints of both ends of the same steel beam at the same time.

[0013] Step 5: Join the components together. Join the roof steel structure, cantilever steel platform and curved steel beam together. Arrange the welding shrinkage allowance value according to the length of the joined components at the measured joining temperature. Then, cut the end allowance of the joined components to control the bevel gap and misalignment during joining.

[0014] Step six: Unloading the temporary support frame.

[0015] As a further improvement of the present invention, in step two, a temporary support platform is also provided at the connection of each segment of the arc-shaped steel beam.

[0016] As a further improvement of the present invention, the temporary support platform includes a grid support frame set on the upper and lower sides of the connection of each arc-shaped steel beam, and the roof steel structure is also provided with a grid support frame distributed at equal intervals.

[0017] As a further improvement of the present invention, in step three, the welding process of the arc-shaped steel beam is specifically as follows: welding from both sides to the middle; in step four, the interface is welded symmetrically on the left and right and top and bottom, and the segments are welded by skip welding.

[0018] As a further improvement of the present invention, the order of the interface welding operation in step four is as follows: first vertical welding, then horizontal welding, and finally overhead welding. After all four sides of an interface are welded, the next interface is then processed.

[0019] As a further improvement of the present invention, the specific method for obtaining the length of the closing component in step five is as follows: the coordinates of the port of the closing part of the component are accurately measured, and the coordinates of the measured points are obtained by establishing a coordinate system. At the same time, it is necessary to control the misalignment of the closing port.

[0020] As a further improvement of the present invention, the specific steps for unloading the temporary support frame in step six are as follows: first, remove the grid support frame at the bottom of the roof steel structure, then remove the temporary support frame at the bottom of the arc-shaped steel beam, and finally remove the temporary support frame at the bottom of the cantilevered steel platform.

[0021] Therefore, the main beneficial effects of the present invention are as follows:

[0022] (1) The present invention provides a large-span curved curtain wall dense column cantilever structure system, which greatly improves the structural stress performance of the curved curtain wall by setting a cantilever structure system composed of box-type dense columns + arc steel beams + roof steel structure + cantilever steel platform, and prevents the redistribution of internal forces after installation;

[0023] (2) Furthermore, by using L-shaped curtain wall column nodes and their connection and installation methods, the various structures are interconnected, thereby improving the installation control accuracy;

[0024] (3) Furthermore, the problem of controlling the installation accuracy of segmented arc steel beams can be solved by measuring and welding the arc steel beams in segments. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only a part of the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is an overall structural diagram of the large-span curved curtain wall cantilever structure system with closely spaced columns in this embodiment;

[0027] Figure 2 This is an isometric drawing of the curved curtain wall cantilever structure system with closely spaced columns in this embodiment;

[0028] Figure 3 This is a plan view of the temporary support frame layout in this embodiment;

[0029] Figure 4This is a schematic diagram of the segmented arc-shaped steel beam in this embodiment;

[0030] Figure 5 This is a schematic diagram of the measurement points for the segmented arc-shaped steel beam in this embodiment;

[0031] Figure 6 This is a schematic diagram of the L-shaped curtain wall column node connection in this embodiment;

[0032] The attached diagram is labeled as follows: 1. Box-type close-column; 2. Curved box beam; 3. Roof steel structure; 4. Cantilevered steel platform; 5. Lower curtain wall column 1-1; 6. Upper curtain wall column 1-2; 7. L-shaped curtain wall column node; 8. Grid support frame; 9. Embedded section 1-11; 10. Measurement point. Detailed Implementation

[0033] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0034] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0035] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0036] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] The present invention will be further described in detail below with reference to the accompanying drawings:

[0038] like Figure 1 , Figure 2 This embodiment provides a large-span curved curtain wall dense column cantilever structure system, including box-shaped dense columns 1. The box-shaped dense columns 1 are sequentially connected and installed with arc-shaped steel beams 2, roof steel structure 3 and cantilever steel platform 4. The box-shaped dense columns 1 include multiple lower curtain wall columns 1-1 and upper curtain wall columns 1-2. The arc-shaped steel beams 2 are horizontally arranged at the upper end of the lower curtain wall columns 1-1. The roof steel structure 3 is connected to the upper end of the arc-shaped steel beams 2 through the upper curtain wall columns 1-2. The cantilever steel platform 4 is horizontally arranged on the inner side of the arc-shaped steel beams 2.

[0039] The installation method based on the above-mentioned curved curtain wall cantilever structure system with closely spaced columns includes the following steps:

[0040] Step 1: Concrete structure construction reaches the outdoor ground level. The embedded parts of the lower curtain wall column 1-1 of the box-type dense column 1 are measured, positioned and embedded according to the construction drawings.

[0041] Step 2: Install the 18.28m elevation curved steel beam, referring to... Figure 3 First, twelve grid-like support frames 6 were erected under both the curved steel beam 2 and the roof steel structure 3. Due to the complex stress on the 18.28m elevation curved steel beam and the high reliability requirements of the node connections, a double grid-like support frame was erected under the curved steel beam as a support platform, and the basement roof slab was reinforced by backfilling. The 18.28m elevation curved steel beam uses welded box-section steel. The curved steel beam 2 experiences complex stress, with a cantilevered steel platform 4 on the inner side of the curve. The box-section closely spaced columns 1 are rigidly eccentrically connected to the curved steel beam 2. Figure 3 To ensure the construction quality and installation accuracy of the rigid nodes, the curved steel beam was processed into 11 sections, and each section of the curved steel beam was equipped with a connecting L-shaped curtain wall column node 5.

[0042] Step 3: The 18.28m elevation curved steel beam is a large-section box-type structural component with a span of 54.86 meters. Curved steel beam 2 is rigidly connected to the lower curtain wall column 1-1 and the upper curtain wall column 1-2, respectively. Ensuring the outer contour and positioning dimensions of curved steel beam 2 during on-site welding is crucial. Strict control of deformation in the circumferential, radial, and vertical directions during box girder construction is necessary. A specific welding process and measurement plan must be developed. The curved steel beam is processed and welded in sections in the workshop, combined with… Figure 5 Measurement points 7 are set at the left and right ends of each curved steel beam and the ends of the upper and lower curtain wall column nodes. A scientific and reasonable measurement plan is formulated based on the actual situation of the steel components. The accuracy of the measurement control network during construction is analyzed to improve the accuracy of measurement and effectively enhance the measurement accuracy control method. After all the curved steel beam 2 and L-shaped curtain wall column nodes 5 are positioned to meet the construction specifications and on-site installation requirements and pass the acceptance test, they are shipped from the factory.

[0043] Specifically, the welding process employed a method of welding from both sides towards the middle, with symmetrical welding at the joints (left-right and top-bottom), and skip welding in sections. A simultaneous welding, measurement, and correction process was used to establish an elevation and horizontal control network. Measurements followed the principle of "from the whole to the part," and construction accuracy was controlled using real-time measurements with total stations and theodolites, ensuring timely feedback and correction to guarantee installation quality. Precise control and real-time monitoring were implemented for the measurement points on the two brackets of the curved steel beam. Based on BIM data, the final position of the curved steel beam was marked in advance, and reliable measures were taken to prevent it from exceeding the designated position. Before hoisting, the dimensions and shape of the steel beam were verified to ensure proper installation after placement. This ensured that the welding deformation and quality of the curved steel beam met the requirements of the construction acceptance specifications.

[0044] Step 4: Since there is a cantilevered steel platform 4 on the inner side of the curved steel beam 2, the curved steel beam bears a large out-of-plane torsional moment under the load of the cantilevered steel platform. In order to balance the torsional moment of the curved steel beam, the node 5 between the curved steel beam 2 and the L-shaped curtain wall column is calculated and analyzed. Considering that the loads of the upper curtain wall columns 1-2 and the roof steel structure 3 are acting on the outer side of the curved steel beam, the node is specially designed as an eccentric L-shaped curtain wall column rigid connection node where the curtain wall load is eccentrically acting on the outer side of the curved steel beam.

[0045] Reference Figure 6 Specifically, the upper node of the L-shaped curtain wall column node 5 adopts an eccentric enlarged head outer beam box connection node, and the lower node of the L-shaped curtain wall column node 5 adopts an eccentric box connection node. The curtain wall nodes are equipped with vertical stiffening steel plates with alignment. The thickness of the stiffening steel plates is the same as the wall thickness of the curtain wall column. In order to ensure the precise alignment of the curtain wall column butt joint plate, horizontal stiffening plates are set within the connection range of the upper and lower nodes. L-shaped curtain wall column node 5 is welded to the curved steel beam 2 in the workshop. The upper curtain wall column 1-2 is directly welded to the L-shaped curtain wall column node 5 on site. To ensure accurate connection between the curved steel beam 2 and the lower curtain wall column 1-1, the upper and lower curtain wall node sections extend outward by 500mm each. The lower curtain wall top is also equipped with a 200mm long embedded section 1-11, which consists of four steel plates. The embedded section 1-11 of the curtain wall column is welded to the lower curtain wall column 1-1 and the curtain wall column node on site according to the actual position of the upper and lower connections. This eccentric L-shaped curtain wall column rigid connection node is an innovative structural design that combines node design with structural stress.

[0046] Step 5: Based on simulation analysis, the installation of the box-shaped dense columns 1 and the arc-shaped box-shaped steel beams 2 of the curved curtain wall will proceed synchronously from both ends towards the middle. Temporary fixing with ear plates will be used during installation. The installation process for the box-shaped dense columns and arc-shaped box-shaped steel beams will involve first hoisting and temporarily fixing the steel structure, then measuring, welding, verifying and correcting, and finally verifying and accepting the final result. This ensures that the overall component accuracy meets the design and construction acceptance specifications. During on-site welding, to prevent excessive stress deformation caused by heat on the steel beams, it was determined that welding operations should not be carried out simultaneously at the joints of the two ends of the same section of steel beam. When welding the box-shaped steel beams, the welding direction of the two opposite sides of the same interface should be kept as consistent as possible. The welding sequence is vertical welding first, then horizontal welding, and finally overhead welding. After all four sides of one interface are welded, the next interface will be proceeded.

[0047] Step Six: Simultaneously with the installation of the lower curtain wall column 1-1 and the curved steel beam 2, the roof steel structure 3 and the cantilevered steel platform 4 are also installed from both ends towards the middle. The closure temperature of the curved steel beam during on-site installation should be between 20℃ and 30℃. Within the planned closure temperature range, precise coordinate measurements are taken at the closure points of the components using a Leica total station. A coordinate system is established to collect coordinates of the measured points, determining the exact length of the closure component at the closure temperature. Based on this length requirement, appropriate welding shrinkage allowance values ​​are arranged, and the closure component is fitted with the port allowance and beveled. The bevel gap during closure is controlled, taking into account temperature deformation calculations and welding shrinkage deformation to reduce the amount of welding and residual welding stress at the closure joint, ensuring welding quality. Simultaneously, the misalignment at the closure joint is also controlled to ensure successful closure.

[0048] Step Seven: After all steel structural components of the lobby have been welded and passed flaw detection and acceptance, and the lobby steel structural support has formed a spatially stable force-bearing system, the temporary support frame will be unloaded. Due to the complex overall stress of the curved curtain wall's closely spaced column support structure system, with the central columns under tension and the two outer columns under compression, and numerous and widespread unloading points, based on the stress analysis and construction calculations of the lobby curtain wall's closely spaced column support structure, and under the premise of ensuring structural safety and ensuring deformation coordination under support conditions, real-time monitoring will be strengthened, and the unloading will be carried out strictly in accordance with the special unloading construction plan. The unloading follows the principle of unloading from top to bottom and from the middle to both sides. First, the lower grid support frame of the roof truss beam will be removed, then the lower temporary support frame of the curved beam will be removed, and finally the lower temporary support frame of the cantilevered roof will be removed.

[0049] The above description is only a specific embodiment of the present invention, but the technical features of the present invention are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present invention are covered by the patent scope of the present invention.

Claims

1. A large-span curved curtain wall dense column cantilever structure system, characterized in that, It includes box-shaped dense columns, which are connected and installed with curved steel beams, roof steel structures and cantilevered steel platforms. The box-shaped dense columns include multiple lower curtain wall columns and upper curtain wall columns. The curved steel beams are horizontally arranged at the upper end of the lower curtain wall columns. The roof steel structure is connected to the upper end of the curved steel beams through the upper curtain wall columns. The cantilevered steel platforms are horizontally arranged on the inner side of the curved steel beams.

2. The installation method of a large-span curved curtain wall dense column cantilever structure system according to claim 1, characterized in that, The installation method includes the following steps: Step 1: Locate and pre-embed the lower curtain wall column; Step 2: Install the curved steel beam. The curved steel beam and the box-type close-column are rigidly eccentrically connected: the curved steel beam is evenly divided into multiple segments, and each segment of the curved steel beam is provided with a connecting L-shaped curtain wall column node. The L-shaped curtain wall column node makes the curtain wall load act eccentrically on the outside of the curved steel beam. Step 3: Measurement and welding of the curved steel beams. Measurement points are set at the left and right ends of each curved steel beam segment and at the upper and lower curtain wall column nodes in Step 2. The welding of multiple curved steel beam segments adopts a correction welding process that combines welding and measurement. Step four: Weld the joints. The installation of the box-shaped dense columns and the arc-shaped steel beams is carried out synchronously from both ends to the middle, and the welding work is carried out at the joints of both ends of the same steel beam at the same time. Step 5: Join the components together. Join the roof steel structure, cantilever steel platform and curved steel beam together. Arrange the welding shrinkage allowance value according to the length of the joined components at the measured joining temperature. Then, cut the end allowance of the joined components to control the bevel gap and misalignment during joining. Step six: Unloading the temporary support frame.

3. The installation method according to claim 2, characterized in that, In step two, a temporary support platform is also provided at the connection of each section of the curved steel beam.

4. The installation method according to claim 3, characterized in that, The temporary support platform includes a grid support frame set on the upper and lower sides of the connection of each arc-shaped steel beam, and the roof steel structure is also equipped with a grid support frame distributed at equal intervals.

5. The installation method according to claim 2, characterized in that, In step three, the welding process for the arc-shaped steel beam is as follows: welding from both sides towards the middle. In step four, the joints are welded symmetrically on the left and right and top and bottom, and the sections are welded using skip welding.

6. The installation method according to claim 2, characterized in that, In step four, the order of interface welding operations is as follows: first vertical welding, then horizontal welding, and finally overhead welding. After all four sides of an interface are welded, the next interface is then processed.

7. The installation method according to claim 2, characterized in that, The specific method for obtaining the length of the merging component in step five is as follows: the coordinates of the port of the merging part of the component are accurately measured, and the coordinates of the measured points are obtained by establishing a coordinate system. At the same time, it is necessary to control the misalignment of the merging port.

8. The installation method according to claim 2, characterized in that, The specific steps for unloading the temporary support frame in step six are as follows: first, remove the grid support frame at the bottom of the roof steel structure; then, remove the temporary support frame at the bottom of the curved steel beam; and finally, remove the temporary support frame at the bottom of the cantilevered steel platform.

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