A construction method for a core tube steel structure building for viewing

Abstract

The present invention relates to the technical field of hybrid structures of steel and concrete, and discloses a construction method for a core tube steel structure building for viewing. By using rigid angle tubes to fix on two vertical edges of the obliquely intersecting grid steel tube, its flexural and torsional stiffness is improved, enabling it to be used as the core tube of a building, thus bringing three benefits: improving the view inside the building, reducing the self-weight of the building, and shortening the construction period; starting from the rigid angle tube with the highest stiffness requirement, arranging the construction sequence in accordance with the principle that the farther away from the rigid angle tube, the later the construction, and the lower the stiffness requirement, the later the construction, to avoid interference between parts with very different properties; when installing the obliquely intersecting grid steel tube, by first installing the concrete-filled steel tubes at the four corner positions to ensure an accurate starting point, and then setting connectors at the intersection points of the members of the obliquely intersecting grid steel tube, ensuring that the positions of the three coordinate control points of each pair of interfaces of the connectors meet the requirements, so that each step of installation can be accurately completed starting from the starting point.

Description

Technical Field

[0001] The present invention relates to the technical field of mixed structures of steel and concrete, and in particular to a construction method of a core tube steel structure building for viewing. Background Art

[0002] Buildings located close to landscapes often require not only the structural strength and aesthetic qualities of conventional buildings but also a higher visual field than conventional buildings. This is because these buildings serve not only as a place for people to gather but also as a viewing platform. For example, sea view apartments often require large floor-to-ceiling windows on the side closest to the sea, or even entire walls covered in curtain walls.

[0003] For buildings that use load-bearing walls as load-bearing components, these walls will undoubtedly severely obstruct the view from inside the building to the outside. Therefore, more landscape buildings are made of steel structures. However, large-scale pure steel structures have their own limitations. Since pure steel structures are not as rigid as reinforced concrete (steel structures are classified as flexible structures, while shear walls are rigid structures), the number of vertical floors of pure steel structures is severely limited (generally no more than 6 floors, and a maximum of no more than 15 floors). If you want to build a steel structure with many floors, you often need to set up a core tube surrounded by reinforced concrete shear walls in the center of the steel structure. However, this brings two new problems. First, there is no outward view from the core tube, resulting in this area having no viewing function. Second, due to the rigidity of the steel structure, the span of the entire floor cannot be too large, and it can only expand outward in a relatively narrow circle around the core tube. In other words, the only area in the entire building that has an outward view is the area around the core tube. Since the core tube occupies a large proportion of the cross-section, only the part close to the landscape in this circle can have a sufficient viewing view, and the other parts will be more or less blocked by the core tube.

[0004] In the existing technology, there are diagonal grid steel cylinders. Since they are enclosed by rods, they do not block the view. If the shear wall core tube can be replaced with a diagonal grid steel cylinder, the problem of building viewing can be solved. The diagonal grid steel cylinder is also a cylindrical structure and has better rigidity than other types of steel structures. If the diagonal grid steel cylinder is used as the core tube of the building, it will bring the following three benefits to the building:

[0005] First, the oblique grid steel tube does not block the view, significantly improving the view from inside the building to the outside;

[0006] Second, it significantly reduces the weight of the building itself, and can be successfully applied to various soft foundations;

[0007] Third, it can greatly shorten the construction period (the assembly of steel components is much faster than the pouring of reinforced concrete).

[0008] However, the diagrid steel tube is still a flexible structure. If used as a building core, its shear stiffness is sufficient, but its torsional and flexural stiffness is insufficient. The inventors discovered that by fixing at least two vertical edges of the diagrid steel tube, its torsional and flexural stiffness is greatly improved, making it suitable for use as a building core. This discovery was successfully applied to the long-span high-rise Hytera Global Headquarters Building in Shenzhen (located on reclaimed land and facing the sea), providing the building with excellent views while significantly reducing its weight.

[0009] However, this structure brings many difficulties to construction:

[0010] First, the mutual interference between the steel structure and the concrete structure is very serious; how to arrange the installation sequence of the components is a big problem;

[0011] Secondly, the installation accuracy requirements for steel components are higher (in the past, the diagonal grid steel tube served as the outer frame of the building, mainly for decoration and restraint, and was not subject to much force. Now it serves as the core tube), and it is also necessary to ensure precise alignment with the embedded parts on the previously poured concrete components. Summary of the Invention

[0012] The invention provides a construction method of a core tube steel structure building for viewing.

[0013] The technical problem to be solved is that the adjacent buildings have high visual requirements, which require the use of steel structures such as diagonal grid steel tubes. However, the rigidity of the diagonal grid steel tubes in some directions is not enough to meet the rigidity requirements of the core tube, and there are difficulties in construction when using them as the core tube.

[0014] To solve the above technical problems, the present invention adopts the following technical solutions: a construction method for a core tube steel structure building for viewing, wherein the cross-section of the core tube steel structure building is rectangular, one side elevation of the building is close to the landscape and is recorded as the landscape side, and the side elevation facing away from the landscape is recorded as the background side; the core tube steel structure building is a frame-core tube structure building, and has three main tubes that vertically penetrate the entire building and are arranged in a herringbone shape on the cross-section of the building, two of the three main tubes are rigid corner tubes set on the background side, and the other is a diagonal grid steel tube set in the middle of the building and serves as the main core tube; the two positive corners of the diagonal grid steel tube close to the background side are respectively fixedly connected to the two rigid corner tubes;

[0015] The outer periphery of the building is also hooped with restraint trusses for further improving the rigidity of the steel structure. The restraint trusses are arranged at intervals on the building in the vertical direction and are fixedly connected to the three main cylinders respectively;

[0016] The construction method comprises the following steps:

[0017] Step 1: After the foundation construction is completed, construct two rigid angle tubes in sections from bottom to top;

[0018] Step 2: After the concrete at the bottom of the two rigid angle tubes has finally set, the diagonal grid steel tubes are constructed section by section from bottom to top and connected to the rigid angle tubes. The construction of the diagonal grid steel tubes is carried out simultaneously with the construction of the rigid angle tubes. The construction progress of the diagonal grid steel tubes lags behind that of the rigid angle tubes so that the concrete in the rigid angle tubes at the connection position has finally set when the rigid angle tubes are connected to the diagonal grid steel tubes.

[0019] Step 3: Construct the floor beams and the building's outer frame. The construction of the floor beams and the building's outer frame lags behind the construction of the diagonal grid steel tube. While the building's outer frame is being constructed, the restraining trusses are constructed on the floors where they are located and are connected to the three main tubes.

[0020] Step 4: Construct the floor slabs of each floor of the building. The construction of the floor slabs lags behind the construction of the building's outer frame.

[0021] Furthermore, the cross section of the diagonal grid steel cylinder is rectangular, and the diagonal grid steel cylinder is surrounded by four steel tube concrete columns respectively arranged at the four vertical edges of the diagonal grid steel cylinder and diagonal grids arranged at the four side facades.

[0022] Furthermore, the rigid angle tube is enclosed by a plurality of rigid columns arranged at intervals along the circumference of the rigid angle tube, and two adjacent rigid columns are fixedly connected by connecting beams arranged at intervals along the vertical direction; each rigid angle tube is also provided with a steel beam grid which is respectively fixedly connected to each rigid column in the rigid angle tube.

[0023] Furthermore, the cross-section of the rigid corner tube is rectangular, and the rigid columns include steel tube concrete columns arranged at the four corners of the rigid corner tube cross-section, and shear wall columns arranged at the remaining positions. The connecting beams on the same horizontal plane of the same rigid corner tube are connected as a whole to form a steel ring beam, and the four corners of the steel ring beam are welded to the steel tube concrete columns and are wrapped by the concrete of each shear wall column; the steel beam grid and the steel ring beam correspond one by one to each floor slab of the building and are flush with the corresponding floor slabs, and the edge of the steel beam grid penetrates the concrete of the shear wall column and is fixedly connected to the steel ring beam; the steel beam grids in the two rigid corner tubes extend outward and are connected as a whole; each of the two rigid corner tubes has a vertical edge that overlaps with a vertical edge of the diagonal grid steel tube, and at each overlapping position, the rigid corner tube and the diagonal grid steel tube share a steel tube concrete column.

[0024] Furthermore, the shear wall columns are provided with embedded parts for connecting the steel beam grid and the oblique grid steel tube; at least one steel tube concrete column for attaching the steel beam grid is also provided between the two rigid angle tubes;

[0025] In step 1, the construction process of each section of the rigid angle tube is divided into the following steps:

[0026] Step 1.1: Install concrete-filled steel tube columns at the four corners of the rigid corner tubes, and install concrete-filled steel tube columns between the two rigid corner tubes to serve as attachment points for the steel beam grid;

[0027] Step 1.2: Tie the steel cages in the shear wall columns and weld the coupling beams to the concrete-filled steel tube columns. The coupling beams pass through the steel cages of each shear wall column. The coupling beams of the two rigid angle tubes are fixedly connected to form a "mesh"-shaped overall structure.

[0028] Step 1.3: Weld the embedded parts to the coupling beam; the embedded parts have interfaces for docking with the ends of the steel beam grids within the rigid angle tubes and the ends of the steel beam grids between the rigid angle tubes;

[0029] Step 1.4: Pour concrete for shear wall columns;

[0030] Step 1.5: Install the steel beam grid. The ends of the steel beam grid inside the rigid angle tubes are fixedly connected to the coupling beams through embedded parts. The ends of the steel beam grid between the rigid angle tubes are fixedly connected to the coupling beams encased in concrete through embedded parts, and are fixedly connected to the coupling beams not encased in concrete and the steel tube concrete column through welding, bolting, or bolt-welding.

[0031] Furthermore, the construction progress of the rigid corner tube is 4 stories ahead of the diagonal grid steel tube, the construction progress of the diagonal grid steel tube is 4-6 stories ahead of the building outer frame, and the construction progress of the building outer frame is 3-4 stories ahead of the floor slab; an attached tower crane is provided on the outer side of the shear wall column facing the view surface of the rigid corner tube, and the tower body of the attached tower crane is connected to the two steel tube concrete columns close to the attached tower crane by an oblique brace extending obliquely downward, and the connection point of the tower body and the shear wall column is connected to the two steel tube concrete columns away from the attached tower crane by an oblique brace extending obliquely downward.

[0032] Furthermore, in the diagonal grid steel cylinder, connectors are provided at the intersections of the rods. The connectors are structures with multiple steel sections extending outward from the intersections of the rods, corresponding one-to-one to the rods at the intersections. The ends of the extended steel sections have docking ports for connecting to the corresponding rods. When the diagonal grid steel cylinder is constructed, the following method is used to control the position and posture of the connectors:

[0033] Use the total station to establish a coordinate control network. Set three coordinate control points on each docking port of the connector. When the connector is hoisted, adjust its position and posture so that the actual coordinates of each coordinate control point are consistent with its set coordinates. After the connector is installed, use the total station to recheck the coordinate control points.

[0034] In step 2, the construction of each segment of the diagonal grid steel cylinder is divided into the following sub-steps:

[0035] Step 2.1: Install two concrete-filled steel tube columns in the diagonal grid steel tube that are not shared with the rigid angle tube;

[0036] Step 2.2: Build a temporary support frame at the bottom of the four side facades of the diagonal grid steel cylinder. Install a layer of connectors on the temporary support frame and record them as initiators. Adjust the position and posture of the initiators to the designed values and then connect them to the foundation.

[0037] Step 2.3: Build the diagonal grid steel cylinder layer by layer on the starter in the order of one layer of rods, one layer of connectors, another layer of rods, and another layer of connectors... and fix them to the rigid angle cylinder.

[0038] Furthermore, the two side walls of the diagonal grid steel tube are parallel to the view surface and stretch outward from the inside of the building and are flush with the view surface and the background surface respectively. In the overlapping part of the diagonal grid steel tube and the rigid angle tube, the diagonal grid steel tube is composed of the side walls of the rigid angle tube; a steel ring beam is provided on the outer periphery of each floor slab of the building where the diagonal grid steel tube is located, and in the two side walls of the diagonal grid steel tube that are flush with the view surface and the background surface, the rods of the diagonal grid steel tube are cross-arranged and fixedly connected with the steel ring beam.

[0039] Furthermore, the diagonal grids in the side walls of the diagonal grid steel cylinder are diamond grids, and each diamond grid is provided with a rod connecting two diagonal points in the horizontal direction of the diamond grid, and is recorded as a hoop rod; the floor slab of the building where the diagonal grid steel cylinder is located is arranged at a diagonal position in the horizontal direction of the diamond grid, and the hoop rod is a floor beam in the floor slab, and the hoop rods under the same floor slab are connected as a whole to form a steel ring beam arranged around the diagonal grid steel cylinder.

[0040] Furthermore, the restraint truss is a plane truss vertically arranged on the plate surface, and the plane truss includes at least two layers of horizontally arranged chords and diagonal webs arranged crosswise between the chords, and the diagonal webs are floor beams of the building; in addition to the portion on the periphery of the building, the restraint truss also includes a portion arranged in a grid-like manner on the cross-section of the building, and the restraint trusses on the periphery and interior of the building are connected as a whole;

[0041] The core tube steel structure building also has a steel structure podium at the bottom, and the podium is equipped with a secondary core tube. The secondary core tube is connected by multiple parallel reinforced concrete shear walls. The shear walls of the secondary core tube are arranged perpendicular to the view surface and are connected to each other through a criss-cross steel beam grid; the part of the core tube steel structure building located above the podium is recorded as a tower house, and a gap for viewing is left between the tower house and the podium, and the top of the podium is recorded as an open viewing platform, and a rigid corner tube is arranged at the dark corner of the tower house; the restrained trusses are arranged at the bottom of the podium, the bottom of the tower house, and the top of the tower house, and the restrained truss at the bottom of the tower house is a cantilever truss.

[0042] Compared with the prior art, the construction method of a core tube steel structure building for viewing has the following beneficial effects:

[0043] In the present invention, by using rigid angle tubes to fix the two vertical edges of the diagonal grid steel tube, its bending and torsional rigidity are improved, so that it can be used as the core tube of the building, thereby bringing the three benefits of improving the visual field inside the building, reducing the building's own weight, and shortening the construction period;

[0044] In the present invention, the construction sequence is arranged by taking the rigid angle tube with the highest rigidity requirement as the starting point, adhering to the principle that the farther away from the rigid angle tube, the later the construction (using the rigid angle tube with the highest rigidity as the position reference), and the lower the rigidity requirement, the later the construction (the higher the rigidity, the smaller the deformable and adjustable space, so it is built first to reduce the interference from other parts). The entire construction process is similar to the process of running in sequence, avoiding interference between different parts and ensuring smooth construction. At the same time, the tower crane is installed on the rigid angle tube installed first, which can provide transportation capacity for subsequent construction.

[0045] In the present invention, when installing the diagonal grid steel cylinder, the steel tube concrete columns (which have high rigidity and can be installed quickly) are first installed at the four corners, and the steel components are installed between the steel tube concrete columns based on the foundation and the steel tube concrete columns to form a steel structure, thereby ensuring that the starting position of the steel structure is accurate during installation; by arranging connectors at the intersections of the rods of the diagonal grid steel cylinder, ensuring that the positions of the three coordinate control points of each docking interface of the connector meet the requirements, so that the tolerances in the entire diagonal grid steel cylinder will not accumulate (because the position of each rod intersection is precisely controlled, and the tolerances cannot accumulate across the rod intersections), each step of the installation can be accurately completed from the starting point, ensuring that the installation accuracy of the entire steel structure meets the requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a structural diagram of the core tube steel structure building in the present invention.

[0047] Figure 2 for Figure 1 Schematic diagram of the steel structure;

[0048] Figure 3 for Figure 1 Cross-sectional diagram of the middle podium; for easy reading, Figure 3-4 The middle shear wall columns are shown in dark black;

[0049] Figure 4 for Figure 1 Schematic cross-section of the middle tower room;

[0050] Figure 5 Schematic diagram of the positional relationship between the rigid corner tube and the diagonal grid steel tube; note that the diagonal grid steel tube extends all the way to the top edge of the diagram, sharing many parts with the rigid corner tube, rather than just being located below the rigid corner tube;

[0051] Figure 6 This is a schematic diagram of the installation method of the attached tower crane;

[0052] Figure 7 This is a schematic diagram of the connector structure. This figure shows a "M"-shaped connector. The "Y"-shaped and "L"-shaped connectors are the same.

[0053] Figure 8 This is a schematic diagram of the arrangement of steel tube concrete columns. The black blocks in the figure are steel tube concrete columns. To facilitate reading the figure, the outlines of the diagonal grid steel cylinder and rigid angle cylinder are marked with dotted lines.

[0054] Among them, 1-diagonal grid steel tube, 2-rigid angle tube, 3-constrained truss, 4-podium, 41-secondary core tube, 5-tower room, 6-open observation deck, 7-attached tower crane, 71-diagonal bracing. DETAILED DESCRIPTION

[0055] like Figure 1-4 As shown in the figure, a construction method of a core tube steel structure building for viewing is provided. The cross section of the core tube steel structure building is rectangular. One side elevation of the building is close to the landscape and is recorded as the view-facing side, and the side elevation facing away from the landscape is recorded as the background side. The core tube steel structure building is a frame-core tube structure building with three main tubes that vertically penetrate the entire building and are arranged in a herringbone shape on the cross section of the building, as shown in the figure. Figure 5 As shown, among the three main tubes, two are rigid corner tubes 2 set on the background surface, and the other is a diagonal grid steel tube 1 set in the middle of the building and serving as the main core tube; the two positive corners of the diagonal grid steel tube 1 close to the background surface are fixedly connected to the two rigid corner tubes 2 respectively.

[0056] Steel structure is a flexible structure in architecture, so the diagonal grid steel tube 1 itself cannot be used as a core tube with rigidity requirements. However, the steel tube has sufficient rigidity when it is very short, but the rigidity drops seriously after it is very long. When the diagonal grid steel tube 1 is very long, its shear rigidity can still meet the requirements, but its bending and torsional rigidity are not enough to meet the requirements. Therefore, a rigid angle tube 2 is used here to fix the two vertical edges of the diagonal grid steel tube 1 that are far apart. After the two vertical edges are fixed, their torsion and bending are restricted, so that they have sufficient torsional and bending rigidity and can be used as the core tube of the building. The rigid angle tube 2, as the name suggests, is a rigid structure. The most common rigid structure in a building is the structure composed of shear walls. Since only the position of the vertical edge of the diagonal grid steel tube needs to be restricted, twisting of this vertical edge will not cause the entire diagonal grid steel tube to twist. Therefore, the rigid angle tube 2 itself does not require sufficient torsional rigidity; sufficient bending rigidity is sufficient. Therefore, the rigid angle tube 2 does not need to be a cylindrical structure completely surrounded by shear walls; it can be a structure with multiple intermittent shear walls, thus allowing for a view outward from within the rigid angle tube 2. In this embodiment, the combined cross-section of the two rigid angle tubes 2 is less than one-quarter the cross-sectional area of the diagonal grid steel tube 1.

[0057] The outer periphery of the building is also hoop-shaped with constraint trusses 3 for further improving the rigidity of the steel structure. The constraint trusses 3 are arranged at intervals on the building in the vertical direction and are fixedly connected to the three main tubes respectively. The role of the constraint trusses 3 here is similar to the gun hoops on ancient cannons or the reinforcement rings of pressure vessels. They interrupt the transmission of deformation and divide a very long structure into sections like bamboo. When calculating the rigidity, the long structure is no longer calculated as a whole, but is divided into multiple shorter structures (with high rigidity) for calculation, thereby improving the rigidity.

[0058] The construction method includes the following steps:

[0059] Step 1: After the foundation construction is completed, two rigid angle tubes 2 are constructed section by section from bottom to top. Section by section construction means that various components including the steel tube concrete columns are assembled section by section from bottom to top.

[0060] Step 2: After the concrete at the bottom of the two rigid angle tubes 2 has finally set, the diagonal grid steel tube 1 is constructed section by section from bottom to top and connected to the rigid angle tube 2. The construction of the diagonal grid steel tube 1 is carried out simultaneously with the construction of the rigid angle tube 2. The construction progress of the diagonal grid steel tube 1 lags behind that of the rigid angle tube 2 so that the concrete in the rigid angle tube 2 at the connection position has finally set when the rigid angle tube 2 is connected to the diagonal grid steel tube 1.

[0061] The rigid angle tube 2 is used to limit the position of the two edges of the diagonal grid steel tube 1. Its shape must strictly meet the requirements, otherwise all the components connected to it will be affected. Therefore, the rigid angle tube 2 must be installed after the concrete has finally set before the auxiliary components above it can be installed. Otherwise, the concrete will be disturbed during the installation process, causing it to deform.

[0062] Step 3: Construction of floor beams and building outer frame. The construction of floor beams and building outer frame lags behind the construction of diagonal grid steel tube 1. While the building outer frame is being constructed, the restraining trusses 3 are constructed on the floors where they are located and are connected to the three main tubes respectively.

[0063] Step 4: Construct the floor slabs of each floor. Floor slab construction lags behind the construction of the building's exterior frame. The floor slabs cannot be constructed after the rigid corner tubes 2 and the diagonal grid steel tubes 1 are completed. Otherwise, the construction period will be extended, many materials will need to be transported over long distances (the floor slabs of high-rise buildings often serve as construction platforms and temporary material storage areas during construction. Even if the floor slab construction lags behind, it can shorten the material transportation distance). Third, the rigid corner tubes 2 and the diagonal grid steel tubes 1 are unstable.

[0064] The shear wall columns are provided with embedded parts for connecting the steel beam grid and the diagonal grid steel tube 1. When constructing each section of the rigid angle tube 2, the steel tube concrete columns at the four corners are first installed. Then the steel cage in the shear wall column is tied and the connecting beam is welded to the steel tube concrete column. Then the embedded parts are fixed to the connecting beam, and then the concrete of the shear wall column is poured. Finally, the steel beam grid (including the inside of the rigid angle tube 2 and the space between the two rigid angle tubes 2) is installed. Here, a climbing formwork is needed to pour concrete. If the steel beam grid is installed first, the climbing formwork cannot be used. Therefore, the embedded parts are installed first, leaving an interface on the shear wall column, and then the steel beam grid and other structures are installed after the concrete is poured. The embedded parts can be fixed to the connecting beam by welding or other methods. This can prevent them from being distorted during the pouring process and increase the connection strength.

[0065] The cross section of the diagonal grid steel cylinder 1 is rectangular, and the diagonal grid steel cylinder 1 is surrounded by four steel tube concrete columns respectively arranged at the four vertical edges of the diagonal grid steel cylinder 1 and diagonal grids arranged at the four side facades. Two rigid corner tubes 2 are arranged on the side of the diagonal grid steel cylinder 1. The rigid corner tubes 2 are arranged at the positions of two adjacent vertical edges of the diagonal grid steel cylinder 1, and are arranged in a herringbone shape with the diagonal grid steel cylinder 1 on the cross section of the building. The advantage of this arrangement is that in many cases, the landscape near the building is only on one side of the building. If the rigid corner tube 2 is set on the side away from the landscape, the impact of the rigid corner tube 2 on the field of vision can be greatly reduced. Because the rigid corner tube 2 selected in this application is actually surrounded by a circle of columns and will not cause serious blocking effects, it still has a certain impact.

[0066] The rigid corner tube 2 is enclosed by a plurality of rigid columns arranged at intervals along the circumference of the rigid corner tube 2, and two adjacent rigid columns are fixedly connected by connecting beams arranged at intervals along the vertical direction; each rigid corner tube 2 is also provided with a steel beam grid fixedly connected to each rigid column in the rigid corner tube 2.

[0067] The cross-section of the rigid corner tube 2 is rectangular. The rigid columns include steel tube concrete columns arranged at the four corners of the cross-section of the rigid corner tube 2, and shear wall columns arranged at the remaining positions. The connecting beams of the same rigid corner tube 2 on the same horizontal plane are connected as a whole to form a steel ring beam. The four corners of the steel ring beam are welded to the steel tube concrete columns and are wrapped by the concrete of each shear wall column; the steel beam grid and the steel ring beam correspond one by one to each floor slab of the building and are flush with the corresponding floor slabs. The edge of the steel beam grid penetrates the concrete of the shear wall column and is fixedly connected to the steel ring beam; the steel beam grids in the two rigid corner tubes 2 extend outward and are connected as a whole; each of the two rigid corner tubes 2 has a vertical edge that overlaps with a vertical edge of the diagonal grid steel tube 1, and at each overlapping position, the rigid corner tube 2 and the diagonal grid steel tube 1 share a steel tube concrete column.

[0068] The shear wall columns here are actually very narrow reinforced concrete shear walls, whose width is usually no more than five times the thickness and at most no more than 10 times the thickness (on the background surface), and the width direction is set along the extension direction of the coupling beams, so they are called columns here. The rigid columns here can all be concrete-filled steel tubular columns, but this is not good for connection because welding is毕竟比埋到混凝土里更麻烦. Here, shear wall columns are selected to form the rigid angle tube 2. In addition to the advantage of easy connection mentioned above, another point is that integral climbing formwork can be used for batch and rapid pouring. And sharing concrete-filled steel tubular columns makes the connection between the rigid angle tube 2 and the obliquely intersecting grid steel tube 1 closer. Although the rigid angle tube 2 here is not a core tube, there is also a steel beam grid integrated with shear walls inside, similar to that of a conventional shear wall core tube (with a higher layout density than the floor beams in the rest part, and there are multiple square grids of different sizes inside). Since the shear wall columns around the rigid angle tube 2 are actually structures similar to reinforced concrete columns, such slender reinforced concrete columns are unstable. Here, the steel beam grid connects the shear wall columns in the two rigid angle tubes 2 together to enhance stability. Note that although the steel beam grid exists on each floor and is actually part of the floor beams, its distribution density is higher than that of the floor beams in the rest part. Because the cross-sectional area of the rigid angle tube 2 is small, if its distribution density is the same as that of the floor beams in the rest part, there will be few grids inside.

[0069] Embedded parts for connecting the steel beam grid and the obliquely intersecting grid steel tube 1 are provided in the shear wall columns; at least one concrete-filled steel tubular column for the steel beam grid to attach to is also provided between the two rigid angle tubes 2;

[0070] In step one, the construction process of each segment of the rigid angle tube 2 is divided into the following sub-steps:

[0071] Step 1.1: As Figure 8 shown, install the concrete-filled steel tubular columns at the four corners of the rigid angle tube 2, and install the concrete-filled steel tubular columns between the two rigid angle tubes 2 for use as attachment points of the steel beam grid; Since the concrete-filled steel tubular columns are also rigid columns and can be installed quickly, whether it is the concrete-filled steel tubular columns at the four corners of the obliquely intersecting grid steel tube 1 or the concrete-filled steel tubular columns at the four corners of the rigid angle tube 2, they need to be installed first to provide an accurate installation site for the installation of other components.

[0072] Step 1.2: Bind the steel reinforcement cages in the shear wall columns and weld the coupling beams to the concrete-filled steel tubular columns. The coupling beams are arranged through the steel reinforcement cages of each shear wall column; The coupling beams of the two rigid angle tubes 2 are fixedly connected to each other to form an overall structure in the shape of a "mu" character; Connecting the coupling beams together has a better stabilizing effect on the slender columns in the rigid angle tube 2, and it can also be used as the obliquely intersecting grid steel tube 1, floor beams, and outer frames itself.

[0073] Step 1.3: Weld the embedded parts to the coupling beams. The embedded parts have interfaces for docking with the ends of the steel beam grid inside the rigid angle tubes 2, as well as the ends of the steel beam grid between the rigid angle tubes 2. These interfaces are flush with the outer surface of the concrete, allowing them to dock with the ends of the steel beams to be installed later while not blocking the climbing formwork during concrete pouring. Of course, if the climbing formwork has a retractable formwork function, it is also possible to leave clearances for these embedded parts in the climbing formwork, allowing them to protrude out of the concrete.

[0074] Step 1.4: Pour concrete for shear wall columns.

[0075] Step 1.5: Install the steel beam grid. The ends of the steel beam grid inside the rigid angle tube 2 are fixedly connected to the connecting beam through embedded parts. The ends of the steel beam grid between the rigid angle tubes 2 are fixedly connected to the connecting beam wrapped by concrete through embedded parts, and are fixedly connected to the connecting beam not wrapped by concrete and the steel tube concrete column through welding, bolting, or bolt-welding.

[0076] In this embodiment, climbing formwork is used to cast concrete for the shear wall columns, so step 1.5 is performed after step 1.4 to avoid affecting the movement of the climbing formwork. If climbing formwork is not used to cast concrete, steps 1.4 and 1.5 can be interchanged, thereby eliminating the need for installation of embedded parts.

[0077] The construction progress of the rigid angle tube 2 is 14 stories ahead of the diagonal grid steel tube, the construction progress of the diagonal grid steel tube 1 is 4-6 stories ahead of the building outer frame, and the construction progress of the building outer frame is 3-4 stories ahead of the floor slab; Figure 6 An attached tower crane 7 used as a construction tool is provided on the outer side of the shear wall column facing the landscape surface of the rigid corner tube 2 shown. The tower body of the attached tower crane 7 is connected to two steel tube concrete columns close to the attached tower crane 7 by a diagonal brace 71 extending obliquely downward, and the connection point between the tower body and the shear wall column is connected to the two steel tube concrete columns away from the attached tower crane 7 by a diagonal brace 71 extending obliquely downward.

[0078] The "layer" here refers to each floor. This means that the height of each section in each area is an integer multiple of the floor height, with the areas constructed ahead being an integer multiple of the floor height. For the rigid corner tube 2, its sides require attached tower cranes 7, similar to conventional shear wall core tubes. However, since it is not closed and cannot effectively support the attached tower cranes 7, steel tube concrete columns are installed at the four corners of the rigid corner tube 2 and connected by diagonal braces 71.

[0079] In the oblique grid steel tube 1, connectors are provided at the intersections of the bars, such as Figure 7As shown, the connector is a structure in which multiple steel sections extend outward from the intersection of the rods, one-to-one corresponding to the rods at the intersection. The ends of the extended steel sections have docking ports for connecting to the corresponding rods. When the diagonal grid steel cylinder 1 is constructed, the following method is used to control the position and posture of the connector:

[0080] Use a total station to establish a coordinate control network. Set three coordinate control points for each docking interface of the connector (three points determine a plane, also known as the docking surface). When the connector is hoisted, adjust its position and posture so that the actual coordinates of each coordinate control point are consistent with its set coordinates. After the connector is installed, use the total station to recheck the coordinate control points.

[0081] In step 2, the construction of each segment of the diagonal grid steel cylinder 1 is divided into the following sub-steps:

[0082] Step 2.1: Install two concrete-filled steel tube columns in the diagonal grid steel tube 1 that are not shared with the rigid angle tube 2;

[0083] Step 2.2: Build a temporary support frame at the bottom of the four side facades of the diagonal grid steel cylinder 1. Install a layer of connectors on the temporary support frame and record them as initiators. Adjust the position and posture of the initiators to the designed values and then connect them to the foundation.

[0084] Step 2.3: Build the diagonal grid steel tube 1 layer by layer on the initiator, following the order of one layer of rods, one layer of connectors, another layer of rods, and another layer of connectors. These are fixedly connected to the rigid angle tube 2. Note that the term "rods" in this article includes all long steel members, including steel beams, steel columns, concrete-filled steel tubular columns, and braces 71.

[0085] The connector here is equivalent to a structure formed by cutting a circle around the intersection of the rods of the diagonal grid steel cylinder 1. Depending on the different intersections, the connector here is mainly divided into three shapes, namely, a "Y" shape (also known as the initiator) set at the bottom and connected to the reserved interface on the foundation, a "L" shape set at the four corners of the diagonal grid steel cylinder 1 (the vertical line of the "Long" is the steel tube concrete column at the four corners of the diagonal grid steel cylinder 1), and a "M" shape set at the remaining positions.

[0086] The two side walls of the diagonal grid steel tube 1, which are parallel to the facing surface, stretch outward from the inside of the building and are flush with the facing surface and the background surface respectively. In the overlapping part of the diagonal grid steel tube 1 and the rigid angle tube 2, the diagonal grid steel tube 1 is composed of the side walls of the rigid angle tube 2; a steel ring beam is set on the outer periphery of each floor slab of the building where the diagonal grid steel tube 1 is located. In the two side walls of the diagonal grid steel tube 1 that are flush with the facing surface and the background surface, the rods of the diagonal grid steel tube 1 are cross-arranged and fixedly connected with the steel ring beam.

[0087] This horizontal stretching of the diagonal grid steel tube 1 has two benefits. First, it improves the appearance of the building. Second, it creates an overlapping portion between the diagonal grid steel tube 1, the rigid angle tube 2, and the building's outer frame (that is, the structure surrounding the building), making the three connections tighter and improving force transmission and structural rigidity. For buildings with a conventional frame-core tube structure, the core tube and the building's outer frame are separated by a floor slab, and the beam-column nodes between the floor beams in the floor slab and the outer frame are usually hinged nodes. The rigidity of the building depends almost entirely on the core tube, and the outer frame does not provide much help. Here, the three parts are directly connected as one, and each part plays a role in improving the rigidity of the building.

[0088] The diagonal grid in the side wall of the diagonal grid steel cylinder 1 is a diamond grid, and each diamond grid is provided with a rod connecting the two diagonal points in the horizontal direction of the diamond grid, and is recorded as a hoop rod; the floor slab of the building where the diagonal grid steel cylinder 1 is located is set at the diagonal position in the horizontal direction of the diamond grid, and the hoop rod is the floor beam in the floor slab. The hoop rods under the same floor slab are connected as a whole to form a steel ring beam arranged around the diagonal grid steel cylinder 1.

[0089] The hoop rods here not only prevent the diamond-shaped lattice from deforming, thereby improving the rigidity, but also act as a reinforcement ring similar to that of a chemical container when connected together.

[0090] The restraint truss 3 is a plane truss arranged vertically on the plate surface. The plane truss includes at least two layers of horizontally arranged chords and diagonal webs arranged crosswise between the chords. The diagonal webs are the floor beams of the building. In addition to the portion on the periphery of the building, the restraint truss 3 also includes a portion arranged in a grid pattern on the cross section of the building. The restraint trusses 3 on the periphery and inside the building are connected as a whole.

[0091] If the restraining trusses 3 were to adopt a structure similar to the reinforcement rings used on chemical containers or the outer rings of ancient cannons, they would need to have a very high rigidity, which is almost impossible for a large-span building. Therefore, in addition to the restraining trusses 3 on the building's perimeter, several restraining trusses 3 are also installed inside, forming a truss network with an outer frame. This ensures sufficient rigidity and can effectively interrupt the transmission of building deformation. Furthermore, the restraining trusses 3 here actually only add a few diagonal webs compared to the original building structure, and the addition of these restraining trusses 3 does not significantly increase the cost.

[0092] The core tube steel structure building also has a steel structure podium 4 at the bottom, and the podium 4 has a secondary core tube 41. The secondary core tube 41 is connected by multiple parallel reinforced concrete shear walls. The shear walls of the secondary core tube 41 are arranged perpendicular to the facing surface and are connected to each other through a criss-crossing steel beam grid; the part of the core tube steel structure building located above the podium 4 is recorded as a tower room 5, and a gap for viewing is left between the tower room 5 and the podium 4, and the top of the podium 4 is recorded as an open viewing platform 6, and the rigid corner tube 2 is arranged at the negative corner position of the tower room 5.

[0093] Here, since the area of the podium 4 is very large and its top is higher than the surrounding trees, street lights and other obstructions, its top can be used as a good platform. Therefore, a part of the floors between the podium 4 and the tower 5 is eliminated, so that the tower 5 and the podium 4 are only connected by three main tubes, leaving an open space as an observation deck. The podium 4 is located at the bottom of the building. The podium 4 does not have a viewing effect. Because the podium 4 is low and is surrounded by street lights, trees and other buildings, the viewing of the podium 4 is basically not considered here. The secondary core tube 41 is no longer made of steel structure like the main core tube, but directly uses reinforced concrete shear walls. Of course, some viewing effects are still taken into consideration here. Therefore, the secondary core tube 41 here is not a closed square tube, but is connected by three walls perpendicular to the view surface. In this way, its torsional strength can meet the requirements of low-rise buildings such as the podium 4, while also providing sufficient viewing vision.

[0094] In this embodiment, the restraining trusses 3 are arranged at the bottom of the podium 4, the bottom of the tower room 5, and the top of the tower room 5. The restraining trusses 3 at the bottom of the tower room 5 are cantilever trusses.

[0095] These locations are transitional locations where stress concentration is likely to occur, and the bottom of the tower room 5 is still cantilevered, so the restraining trusses 3 are set here. Of course, if the floors continue to be raised, more restraining trusses 3 will need to be set in the building.

[0096] Rigid columns are placed along the vertical edges of each rigid corner tube 2, perpendicular to the background. This creates wide doors in these two walls, allowing for easy access to the outside world for construction materials. Furthermore, high-density steel beams within and between the two rigid corner tubes 2 allow for gangplanks to be laid, forming a temporary construction platform for personnel and materials. The doors are located at the ends of these platforms.

[0097] The embodiments described above are merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A construction method for a core tube steel structure building for viewing, the cross-section of the core tube steel structure building is rectangular, one side elevation of the building is set close to the view and is denoted as the view-facing side, and the side elevation facing away from the view is denoted as the background side; It is characterized in that: The core tube steel structure building is a building with a frame-core tube structure, and is provided with three main tubes vertically penetrating the whole building and arranged in a triangular shape on the building cross-section. Among the three main tubes, two are rigid corner tubes (2) arranged on the background side, and the other is an obliquely intersecting grid steel tube (1) arranged in the middle of the building and serving as the main core tube; The two outer corners of the obliquely intersecting grid steel tube (1) close to the background side are respectively fixedly connected to the two rigid corner tubes (2); A restraint truss (3) for further enhancing the stiffness of the steel structure is also hoop-mounted on the outer periphery of the building. The restraint truss (3) is arranged at intervals along the vertical direction on the building and is respectively fixedly connected to the three main tubes; The construction method includes the following steps: Step 1: After the foundation construction is completed, the two rigid corner tubes (2) are constructed section by section from bottom to top; Step 2: After the concrete at the bottom of the two rigid corner tubes (2) has finally set, the obliquely intersecting grid steel tube (1) is constructed section by section from bottom to top and connected to the rigid corner tubes (2). The construction of the obliquely intersecting grid steel tube (1) is carried out together with the construction of the rigid corner tubes (2), and the construction progress of the obliquely intersecting grid steel tube (1) lags behind that of the rigid corner tubes (2) so that the concrete in the rigid corner tubes (2) at the connection position has finally set when the obliquely intersecting grid steel tube (1) is connected to the rigid corner tubes (2); Step 3: Construct the floor beams and the building outer frame. The construction of the floor beams and the building outer frame lags behind the construction of the obliquely intersecting grid steel tube (1); And while the building outer frame is being constructed, the restraint truss (3) is constructed on the floors with the restraint truss (3) and the restraint truss (3) is respectively connected to the three main tubes; Step 4: Construct the floors of each layer of the building. The construction of the floors lags behind the construction of the building outer frame.

2. A construction method for a core tube steel structure building for viewing according to claim 1, It is characterized in that: The cross-section of the obliquely intersecting grid steel tube (1) is rectangular, and the obliquely intersecting grid steel tube (1) is enclosed by four concrete-filled steel tubes respectively arranged at the positions of the four vertical edges of the obliquely intersecting grid steel tube (1) and an obliquely intersecting grid arranged at the positions of the four side elevations.

3. A construction method for a core tube steel structure building for viewing according to claim 2, It is characterized in that: The rigid corner tube (2) is enclosed by a plurality of rigid columns arranged at intervals along the circumferential direction of the rigid corner tube (2), and adjacent two rigid columns are fixedly connected by connecting beams arranged at intervals along the vertical direction; A steel beam grid respectively fixedly connected to each rigid column in the rigid corner tube (2) where it is located is also arranged in each rigid corner tube (2).

4. A construction method for a core tube steel structure building for viewing according to claim 3, It is characterized in that: The cross-section of the rigid angle tube (2) is rectangular. The rigid column includes concrete-filled steel tube columns arranged at the four corners of the cross-section of the rigid angle tube (2) and shear wall columns arranged at the remaining positions. The continuous beams on the same horizontal plane of the same rigid angle tube (2) are connected into one body to form a steel ring beam. The four corners of the steel ring beam are welded to the concrete-filled steel tube columns and are wrapped by the concrete of each shear wall column; the steel beam grid and the steel ring beam correspond to each floor of the building one by one and are flush with the corresponding floor. The edge of the steel beam grid penetrates the concrete of the shear wall column and is fixedly connected to the steel ring beam; the steel beam grids in the two rigid angle tubes (2) extend outward and are connected into one body; each of the two rigid angle tubes (2) has a vertical edge overlapping with a vertical edge of the obliquely intersecting grid steel tube (1), and at each overlapping position, the rigid angle tube (2) and the obliquely intersecting grid steel tube (1) share a concrete-filled steel tube column.

5. The construction method of a core tube steel structure building for viewing according to claim 4, characterized in that: embedded parts for connecting the steel beam grid and the obliquely intersecting grid steel tube (1) are arranged in the shear wall columns; at least one concrete-filled steel tube column for attaching the steel beam grid is also arranged between the two rigid angle tubes (2); In step one, the construction process of each segment of the rigid angle tube (2) is divided into the following sub-steps: Step 1.1: Install the concrete-filled steel tube columns at the four corners of the rigid angle tube (2) and install the concrete-filled steel tube columns used as the attachment points for the steel beam grid between the two rigid angle tubes (2); Step 1.2: Bind the steel reinforcement cages in the shear wall columns and weld the continuous beams to the concrete-filled steel tube columns. The continuous beams are arranged through the steel reinforcement cages of each shear wall column; the continuous beams of the two rigid angle tubes (2) are fixedly connected to each other to form an "eye" - shaped integral structure; Step 1.3: Weld the embedded parts to the continuous beams; the embedded parts are provided with interfaces for butt - jointing with the ends of the steel beam grid inside the rigid angle tube (2) and the ends of the steel beam grid between the rigid angle tubes (2); Step 1.4: Pour the concrete of the shear wall columns; Step 1.5: Install the steel beam grid. The ends of the steel beam grid inside the rigid angle tube (2) are fixedly connected to the continuous beams through the embedded parts, and the ends of the steel beam grid between the rigid angle tubes (2) are fixedly connected to the continuous beams wrapped by concrete through the embedded parts and are fixedly connected to the continuous beams and the concrete-filled steel tube columns that are not wrapped by concrete by means of welding, bolting, or bolt - welding connection.

6. The construction method of a core tube steel structure building for viewing according to claim 1, characterized in that: The construction progress of the rigid corner tube (2) is 4 floors ahead of that of the skewed grid steel tube (1), the construction progress of the skewed grid steel tube (1) is 4 - 6 floors ahead of that of the building exterior frame, and the construction progress of the building exterior frame is 3 - 4 floors ahead of that of the floor slab; an attached tower crane (7) is arranged on the outer side surface of the shear wall columns on the landscape-facing side of the rigid corner tube (2), and the tower body of the attached tower crane (7) is connected to two concrete-filled steel tubes close to the attached tower crane (7) through inclined braces (71) extending obliquely downward, and the connection point of the tower body and the shear wall columns is connected to two concrete-filled steel tubes away from the attached tower crane (7) through inclined braces (71) extending obliquely downward.

7. A construction method of a core tube steel structure building for viewing according to claim 4, characterized in that: In the skewed grid steel tube (1), connectors are respectively arranged at the positions of the intersection points of each member. The connector is a structure with multiple steel section segments extending outward from the center of the member intersection point and corresponding to each member at the intersection point position one by one. The end of the extended steel section segment is provided with a docking port for connecting with the corresponding member; when building the skewed grid steel tube (1), the following method is used to control the position and attitude of the connector: A coordinate control network is established by using a total station. Three coordinate control points are set for each docking port of the connector. When the connector is hoisted, its position and attitude are adjusted so that the actual coordinates of each coordinate control point are consistent with the set coordinates. After the connector is installed, the coordinate control points are rechecked by using the total station. In step two, the construction of each segment of the skewed grid steel tube (1) is divided into the following sub-steps: Step 2.1: Install two concrete-filled steel tubes in the skewed grid steel tube (1) that are not shared with the rigid corner tube (2). Step 2.2: Build a temporary support frame at the bottom of the four side facades of the skewed grid steel tube (1), install a layer of connectors on the temporary support frame and record them as starting connectors. Adjust the position and attitude of the starting connectors to the design values, and then connect them to the foundation. Step 2.3: In the order of one layer of members, one layer of connectors, then one layer of members, and then one layer of connectors, build the skewed grid steel tube (1) layer by layer on the starting connectors and fixedly connect it to the rigid corner tube (2).

8. A construction method of a core tube steel structure building for viewing according to claim 1, characterized in that: The two side walls of the skewed grid steel tube (1) parallel to the landscape-facing side are stretched outwards from the inside of the building and are respectively flush with the landscape-facing side and the background side. In the overlapping part of the skewed grid steel tube (1) and the rigid corner tube (2), the skewed grid steel tube (1) is composed of the side walls of the rigid corner tube (2); a steel ring beam is arranged on the outer periphery of each floor slab of the building where the skewed grid steel tube (1) is located. In the two side walls of the skewed grid steel tube (1) that are flush with the landscape-facing side and the background side, the members of the skewed grid steel tube (1) are arranged crosswise with the steel ring beam and fixedly connected.

9. A construction method of a core tube steel structure building for viewing according to claim 1, characterized in that: The diagonal grid in the side wall of the diagonal grid steel cylinder (1) is a diamond grid, and each diamond grid is provided with a rod connecting two diagonal points in the horizontal direction of the diamond grid, and is recorded as a hoop rod; the floor of the building where the diagonal grid steel cylinder (1) is located is arranged at a diagonal position in the horizontal direction of the diamond grid, and the hoop rod is a floor beam in the floor, and the hoop rods under the same floor are connected as a whole to form a steel ring beam arranged around the diagonal grid steel cylinder (1).

10. The construction method of a core tube steel structure building for viewing according to claim 1, Features: The restrained truss (3) is a plane truss arranged vertically on the plate surface, and the plane truss comprises at least two layers of horizontally arranged chords and diagonal webs arranged crosswise between the chords, and the diagonal webs are floor beams of the building; in addition to the portion at the periphery of the building, the restrained truss (3) also comprises a portion arranged in a grid-like manner on the cross section of the building, and the restrained trusses (3) at the periphery and inside of the building are connected as a whole; The bottom of the core tube steel structure building is also provided with a steel structure podium (4), and the podium (4) is provided with a secondary core tube (41), and the secondary core tube (41) is formed by connecting a plurality of mutually parallel reinforced concrete shear walls, and the shear walls of the secondary core tube (41) are arranged perpendicular to the landscape surface and are connected to each other through a crisscrossing steel beam grid; the portion of the core tube steel structure building located above the podium (4) is recorded as a tower (5), and a gap for viewing is left between the tower (5) and the podium (4), and the top of the podium (4) is recorded as an open viewing platform (6), and the rigid corner tube (2) is arranged at the inner corner of the tower (5); the restraining truss (3) is arranged at the bottom of the podium (4), the bottom of the tower (5), and the top of the tower (5), and the restraining truss (3) at the bottom of the tower (5) is a cantilever truss.

Images