Construction method of cantilever steel truss under hanging inclined suspender without pressure

Abstract

The application discloses a construction method without pressure in the construction process of a cantilever steel truss lower hanging inclined suspender, which is constructed from bottom to top, and the floor steel beam installation can be started without waiting for the completion of the top truss installation, so that the suspension structure and the core tube can be synchronously installed, and the construction period of the whole construction is effectively shortened. The suspension structure is installed by using temporary support, the installation sequence is similar to that of a common frame structure, common steel structure installation mechanical equipment such as a tower crane, a truck crane and a caterpillar crane can be used, the construction method is simple, the steel structure installation cost is reduced, and it is ensured that the suspender only bears tension and does not bear pressure in the construction process. In addition, the application also clearly defines the calculation formula of the floor elevation of the suspension structure, and the influence of the structure deformation on the suspender installation in the unloading process of the suspension structure is eliminated by controlling the floor beam elevation.

Description

Technical Field

[0001] This invention belongs to the field of construction, specifically relating to a pressure-free construction method for suspending inclined rods under a cantilever steel truss. Background Technology

[0002] With the development of building structures, unconventional structural forms such as inclined suspended steel structures are emerging more and more frequently. For these unconventional structural forms, it is necessary to propose reasonable construction and installation methods to ensure that the construction quality and schedule of the corresponding structures meet actual requirements.

[0003] The characteristics of the inclined suspended structure are as follows: the center is a core tube, the top layer is a cantilever steel truss, the suspended structure is connected to the top cantilever truss structure through hanging nodes, and the lower part is connected to each floor through inclined hangers, so as to achieve the effect of column-free space in the lower floors. The overall shape of the structure is larger at the top and smaller at the bottom. The hangers only bear tensile force and do not bear compressive force.

[0004] To ensure that the hangers do not bear pressure during construction, traditional suspension structures require the core tube and top truss structure to be completed first, followed by construction from top to bottom. This results in low installation efficiency and is detrimental to the overall project schedule. However, the hangers in traditional suspension structures are vertical, and their installation method is not suitable for inclined suspension structures.

[0005] Moreover, the traditional construction procedure for suspended structures is as follows: (1) construct the core tube to the top floor; (2) erect temporary support frame for the cantilever truss; (3) install the cantilever truss structure; (4) dismantle the temporary support frame for the cantilever truss; (5) assemble the floor steel structure on the ground; (6) lift or jack up the assembled floor steel structure; (7) repeat the above steps (5) and (6) until the entire structure is installed.

[0006] The problems with this construction sequence are as follows: the steel structure suspension structure can only be constructed after the core tube and top truss are installed, which prolongs the overall construction period of the project; the entire floor steel structure must be assembled on the ground before it can be lifted or jacked up, and the next step of work cannot be carried out before it is lifted or jacked up in place, resulting in a large construction vacuum period; the installation process generally cannot use common steel structure installation machinery and equipment such as tower cranes, truck cranes, and crawler cranes, which makes the construction difficult and the installation cost high; and the structural rigidity is low during the jacking or lifting process, which poses a significant safety hazard.

[0007] Therefore, optimizing the installation method of steel structure suspension structures, improving installation efficiency, and shortening project time is a technical problem that urgently needs to be solved. Summary of the Invention

[0008] The purpose of this invention is to solve the problems of low installation efficiency and long project duration in the installation of steel structure suspension structures, and to provide a pressure-free construction method for the construction of inclined suspension rods under cantilever steel trusses.

[0009] The specific technical solution adopted in this invention is as follows:

[0010] A pressure-free construction method for suspending inclined hangers under a cantilever steel truss, the method comprising:

[0011] S1. Temporary steel beam supports are erected on the ground around the constructed core tube, and the lowest floor steel beam of the suspension structure is installed under the support of the temporary steel beam supports. The connection nodes between the floor steel beam and the core tube are temporarily connected with ordinary bolts and the welds are not welded for the time being. The hanger connection section extending from the top surface of the steel beam is fixedly installed on the lowest floor steel beam.

[0012] S2. For other floors on the core tube that require the installation of floor steel beams, construction shall proceed sequentially from bottom to top. For each construction floor, temporary supports for the steel beams required for the current construction floor shall be erected first on the foundation of the temporary supports for the steel beams of the floors below and the floor steel beams. Then, a main inter-floor section of the hanger rod shall be fixedly connected to the hanger rod connecting section fixedly installed on the floor steel beams of the floors below by means of a lower connecting lug plate. The floor steel beams corresponding to the current construction floor shall be installed under the support of the temporary supports for the steel beams. The connection nodes between the floor steel beams corresponding to the current construction floor and the core tube shall be temporarily connected using ordinary bolts, and the welds shall not be welded for the time being. Hanger rod connecting sections extending from the top and bottom surfaces of the steel beams shall be fixedly installed on the floor steel beams corresponding to the current construction floor. The bottom of the hanger rod connecting section shall only be connected to the main inter-floor section of the hanger rod below, but the lower connecting lug plate shall not be installed for the time being.

[0013] S3. After all the floor steel beams on all floors have been installed, erect temporary truss supports on the foundation of the top floor steel beam temporary supports and floor steel beams, and install cantilever steel trusses under the support of the temporary truss supports. After the cantilever steel trusses are installed, remove the temporary truss supports.

[0014] S4. Suspend and fix a supplementary section of the hanger rod at the truss hanging node at the bottom of the cantilever steel truss, and weld the bottom of the supplementary section of the hanger rod to the top of the hanger rod connection section fixedly installed on the top floor steel beam; at the same time, replace the ordinary bolts in the connection node between the top floor steel beam and the core tube with high-strength bolts and weld the weld.

[0015] S5. For the remaining floors where floor steel beams are installed, construction shall proceed sequentially from top to bottom, so that the floor steel beams form a suspension system with the cantilever steel truss layer by layer. For each construction floor, the temporary supports of the steel beams below the floor steel beams of the construction floor must be removed first. Except for the bottom floor, the bottom of the connecting section of the hanger fixed on the floor steel beam of the current construction floor must be fixed to the main section of the hanger between the floors below through the upper connecting lugs. Then, the joint of the three sections of hanger between the current construction floor and the floors below is welded and fixed, and the upper and lower connecting lugs at the weld joint are removed. At the same time, the ordinary bolts in the connection nodes between the floor steel beams and the core tube corresponding to the current construction floor are replaced with high-strength bolts, and the welds are welded.

[0016] Preferably, a construction process simulation should be conducted before construction to determine the vertical displacement γ of the lower chord hanger node of the cantilever steel truss under its own weight load, and the vertical displacement A at the top surface of the floor steel beam under its own weight load after any i-th floor forms a suspension system with the cantilever steel truss. i A) The increase in vertical displacement at the lower chord hanger node of the cantilever steel truss after all floors of concrete slabs have been poured; B) The increase in vertical deflection at the lower chord hanger node of the cantilever steel truss after the curtain wall installation is completed; C)

[0017] During construction, it is necessary to control the construction elevation of the lower chord hanger node of the cantilever steel truss. Simultaneously, the construction elevation of the steel beams on the i-th floor needs to be controlled. In the formula, H is the design elevation of the lower chord hanger node of the cantilever steel truss, and h is... k Let be the floor height of the k-th floor, n be the floor number of the bottom layer of the inclined suspension structure, and a be the total number of floors below the cantilever steel truss in the inclined suspension structure, i = n, n+1, ..., n+a.

[0018] Preferably, the construction progress of the core tube needs to be at least 1 to 2 floors ahead of the installation progress of the floor steel beams.

[0019] Preferably, the inclined hangers used to connect the floor steel structure are pre-processed in sections at the factory. The inclined hangers are divided into the main body section between floors and the connecting section. The main body section between floors is the main body of the inclined hangers between floors, and the connecting section is fixed to the floor steel beam. Its top end extending from the top surface of the floor steel beam and its bottom end extending from the bottom surface of the floor steel beam are used to connect the main body section between the upper and lower floors.

[0020] Preferably, the temporary support for the steel beam is made of tower crane standard sections, square tubes, H-beams, or lattice columns.

[0021] As a preferred option, the hoisting equipment used for hoisting components during construction is truck crane, tower crane, or crawler crane.

[0022] Preferably, the truss suspension node and the rear section of the suspension rod are suspended and fixed by a pin.

[0023] Preferably, the upper and lower connecting lugs are temporarily connected to the two connecting rod sections by bolts, and can be removed after the connecting rod sections are welded and fixed.

[0024] As a preferred option, after the steel structure construction of all floors is completed, the concrete floor slabs are poured on the foundation of the steel beams on each floor in a top-down construction sequence.

[0025] As a preferred option, the curtain wall installation for each floor is carried out after the concrete floor slabs of all floors have been poured.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] This construction method proceeds from bottom to top, allowing for the installation of floor steel beams without waiting for the top truss to be completed. This enables the suspended structure and core tube to be installed simultaneously, effectively shortening the overall construction period. The suspended structure utilizes temporary supports, and the installation sequence is similar to that of typical frame structures. Common steel structure installation machinery such as tower cranes, truck cranes, and crawler cranes can be used, simplifying the construction method, reducing steel structure installation costs, and ensuring that the hangers only bear tensile forces and not compressive forces during construction. Furthermore, this invention clarifies the calculation formulas for the floor elevations of the suspended structure and eliminates the impact of structural deformation on hanger installation during unloading by controlling the floor beam elevations. Attached Figure Description

[0028] Figure 1 Schematic diagram of the suspension structure;

[0029] Figure 2 Schematic diagram of truss suspension nodes, rod segments, and temporary construction measures;

[0030] Figure 3 A schematic diagram of step 1 of the construction method;

[0031] Figure 4 Schematic diagram of step 2 of the construction method;

[0032] Figure 5 Schematic diagram of step 3 of the construction method;

[0033] Figure 6 Schematic diagram of step 4 of the construction method;

[0034] Figure 7 Schematic diagram of step 5 of the construction method;

[0035] Figure 8 Schematic diagram of step 6 of the construction method;

[0036] Figure 9 Schematic diagram of step 7 of the construction method;

[0037] Figure 10 Schematic diagram of step 8 of the construction method;

[0038] Figure 11 Schematic diagram of step 9 of the construction method;

[0039] Figure 12 Schematic diagram of step 10 of the construction method;

[0040] Figure 13 Schematic diagram of step 11 of the construction method;

[0041] Figure 14 A schematic diagram of step 12 of the construction method. Detailed Implementation

[0042] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. Technical features in various embodiments of the present invention can be combined accordingly without mutual conflict.

[0043] In the description of this invention, it should be understood that when an element is considered to be "connected" to another element, it can be a direct connection to the other element or an indirect connection, i.e., there is an intermediate element. Conversely, when an element is said to be "directly" connected to another element, there is no intermediate element.

[0044] In the description of this invention, it should be understood that the terms "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" and "second" may explicitly or implicitly include at least one of those features.

[0045] In a preferred embodiment of the present invention, a pressure-free construction method is provided for constructing inclined suspension rods under a cantilever steel truss. The inclined suspension rod structure ultimately formed by this construction method is as follows: Figure 1As shown, the inclined suspension structure consists of a core tube 1, a cantilever steel truss 2, truss suspension nodes 3, suspension rods 4, floor suspension nodes 5, floor steel beams 6, and steel beam-core tube connection nodes 9. The cantilever steel truss 2 at the top of the core tube 1 is connected to the suspension rods 4 through the truss suspension nodes 3. The suspension rods 4 are composed of a series of suspension rod segments spliced ​​together and are connected to the floor steel beams 6 of each floor through the floor suspension nodes 5. The floor steel beams 6 of each floor are connected to the core tube 1 through the steel beam-core tube connection nodes 9.

[0046] In this invention, for ease of description, the lowest layer of the suspended structure is defined as n, and the number of suspended structure layers below the cantilever steel truss 2 is defined as a. To facilitate construction between different layers, the hanger 4 needs to be segmented, thus as follows: Figure 2 As shown, in the inclined suspension structure, the floor number i of any floor satisfies i = n, n+1, ..., n+a. The floor where the cantilever steel truss 2 is located is hj. The attached drawing of the steel beam 6 on the nth floor is 6-1, and the attached drawing of its connection node 9 with the core tube 1 is 9-1; the attached drawing of the steel beam 6 on the (n+1)th floor is 6-2, and the attached drawing of its connection node 9 with the core tube 1 is 9-2; the attached drawing of the steel beam 6 on the (n+a-1)th floor is 6-4, and the attached drawing of its connection node 9 with the core tube 1 is 9-4; the attached drawing of the steel beam 6 on the (n+a)th floor is 6-3, and the attached drawing of its connection node 9 with the core tube 1 is 9-3.

[0047] In this embodiment of the invention, the hanger 4 is segmented and cut 500mm from the upper and lower surfaces of the steel beam 6 on each floor. Therefore, the inclined hanger is segmented into a main inter-floor section 402 and a connecting section. The main inter-floor section 402 forms the main body of the inclined hanger between floors, while the connecting section is fixed to the floor steel beam. Its top end 403 extending from the top surface of the floor steel beam and its bottom end 401 extending from the bottom surface of the floor steel beam are used to connect the main inter-floor sections 402 of the hanger between the upper and lower floors, respectively. In this embodiment, the top end 403 and bottom end 401 of the connecting section are 500mm from the floor steel beam. Each hanger segment used to connect the inclined hangers of the floor steel structure can be pre-processed in the factory and then transported to the construction site for assembly. Before hoisting, the floor steel beam 6 can be assembled with the corresponding connecting section into a single integral component. Before each hanger segment is welded and fixed, it needs to be temporarily connected by the connecting lugs 8. For a main inter-floor section 402 of a hanger, its top and bottom ends need to be connected to the bottom end 401 of the upper floor hanger connection section and the top end 403 of the lower floor hanger connection section, respectively. Therefore, the connecting lugs 8 need to be divided into upper connecting lugs 801 and lower connecting lugs 802. The connecting lugs 8 can be composed of steel plates and mounting bolts. Bolt holes are opened on the steel plates. The steel plates are covered on the lugs at the ends of the hanger segments to be connected. After the bolt holes are aligned, the mounting bolts are inserted and tightened to achieve the temporary connection of the hanger segments before welding.

[0048] In addition, in the embodiments of the present invention, the floor steel beams 6 and the connecting steel beams on the core tube 1 form a connection node 9. The components required for the construction of the connection node 9 include ordinary bolts 902 and high-strength bolts 903. Both are used to connect the floor steel beams 6 and the connecting steel beams on the core tube 1 at different construction stages. The two steel beams can be connected by connecting steel plates with bolt holes 901. Both ordinary bolts 902 and high-strength bolts 903 can be inserted into the bolt holes 901. After the floor steel beams 6 are finally unloaded and form a suspension system with the cantilever steel truss, the butt joint between the floor steel beams 6 and the connecting steel beams on the core tube 1 can be welded, and the corresponding connecting steel plates can be removed.

[0049] In addition, in the embodiments of the present invention, temporary supports 7 are also required at the bottom of the steel beams 6 on each floor and the cantilever steel truss 2. For ease of description, the reference numeral for the temporary support 7 of the steel beams 6 on the nth floor is 7-1, the reference numeral for the temporary support 7 of the steel beams on the n+1th floor is 7-2, the reference numeral for the temporary support 7 of the steel beams on the n+ath floor is 7-3, and the reference numeral for the temporary support 7 of the truss on the hjth floor where the cantilever steel truss 2 is located is 7-4. The temporary supports 7 at the bottom of the steel beams 6 on each floor and the cantilever steel truss 2 can be standard tower crane sections and square tubes, or other forms such as H-beams and lattice columns.

[0050] In an embodiment of the present invention, the pressure-free construction method for suspending inclined rods under the cantilever steel truss specifically includes the following steps S1 to S5:

[0051] S1. Temporary steel beam supports are erected on the ground around the constructed core tube (enough to support the installation of the lowest floor steel beam of the inclined hanger structure). The lowest floor steel beam of the suspension structure is installed under the support of the temporary steel beam supports. The connection nodes between the floor steel beam and the core tube are temporarily connected with ordinary bolts, and the welds are not welded for the time being. The hanger connection section extending from the top surface of the steel beam is fixedly installed on the lowest floor steel beam.

[0052] S2. For other floors on the core tube that require the installation of floor steel beams, construction shall proceed sequentially from bottom to top. For each construction floor, temporary supports for the steel beams required for the current construction floor shall be erected first on the foundation of the temporary supports for the steel beams of the floors below and the floor steel beams. Then, a main inter-floor section of the hanger rod shall be fixedly connected to the hanger rod connecting section fixedly installed on the floor steel beam of the floors below by means of a lower connecting lug. The floor steel beam corresponding to the current construction floor shall be installed under the support of the temporary supports for the steel beams. The connection node between the floor steel beam corresponding to the current construction floor and the core tube shall be temporarily connected using ordinary bolts, and the weld shall not be welded for the time being. Hanger rod connecting sections extending from the top and bottom surfaces of the steel beam shall be fixedly installed on the floor steel beam corresponding to the current construction floor. The bottom of the hanger rod connecting section shall only be connected to the main inter-floor section of the hanger rod below, but the lower connecting lug shall not be installed for the time being.

[0053] S3. After all the floor steel beams on all floors have been installed, erect temporary truss supports on the foundation of the top floor steel beam temporary supports and floor steel beams, and install cantilever steel trusses under the support of the temporary truss supports. After the cantilever steel trusses are installed, remove the temporary truss supports.

[0054] S4. Suspend and fix a supplementary section of the hanger rod at the truss hanging node at the bottom of the cantilever steel truss, and weld the bottom of the supplementary section of the hanger rod to the top of the hanger rod connection section fixedly installed on the top floor steel beam; at the same time, replace the ordinary bolts in the connection node between the top floor steel beam and the core tube with high-strength bolts and weld the weld.

[0055] S5. For the remaining floors where floor steel beams are installed, construction shall proceed sequentially from top to bottom, so that the floor steel beams form a suspension system with the cantilever steel truss layer by layer. For each construction floor, the temporary supports of the steel beams below the floor steel beams of the construction floor must be removed first. Except for the bottom floor, the bottom of the connecting section of the hanger fixed on the floor steel beam of the current construction floor must be fixed to the main section of the hanger between the floors below through the upper connecting lugs. Then, the joint of the three sections of hanger between the current construction floor and the floors below is welded and fixed, and the upper and lower connecting lugs at the weld joint are removed. At the same time, the ordinary bolts in the connection nodes between the floor steel beams and the core tube corresponding to the current construction floor are replaced with high-strength bolts, and the welds are welded.

[0056] S6. After the steel structure construction of all floors is completed, the concrete floor slabs can be poured on the foundation of the steel beams on each floor, following the subsequent construction sequence from top to bottom. After the concrete floor slabs of all floors are poured, the curtain wall installation of each floor can then proceed according to the subsequent construction sequence.

[0057] The following describes the specific implementation of the construction method shown in S1 to S6 above, based on the previously defined layer numbers n to n+a, i.e., the bottom layer of the inclined suspension structure is n, the number of suspension structure layers below the truss is a (a can be 0, 1, 2, ...), and the layer where the cantilever steel truss 2 is located is hj. The construction method in this embodiment can be referred to as steps 1 to 12. In the entire construction method, the construction progress of the core tube needs to lead the installation progress of the floor steel beams 6-1 by at least 1 to 2 floors to ensure that the floor steel beams 6 on each floor can be installed smoothly.

[0058] Step 1: See Figure 3 As shown, a temporary support 7-1 for the bottom steel beam is erected using a crane. Of course, in this invention, various steel structure installation components and equipment can be installed not only using truck cranes, but also using other lifting equipment such as tower cranes and crawler cranes.

[0059] Step 2: See Figure 4 As shown, the n-story steel beam 6-1 is installed. Before hoisting, a connecting rod section extending from the top of the steel beam 6-1 is pre-installed. The connection node 9-1 between the n-story steel beam 6-1 and the core tube 1 is connected using ordinary bolts 902, and the weld 904 is not welded temporarily. That is, the n-story steel beam 6-1 and the connecting steel beams on the core tube 1 that connect to the n-story steel beam 6-1 are temporarily connected by connecting steel plates and ordinary bolts 902, while the joint between the connecting steel beams of the n-story steel beam 6-1 is not welded temporarily.

[0060] Step 3: See Figure 5As shown, on the basis of the floor steel beam 6-1 and the bottom steel beam temporary support 7-1, an n+1 layer of steel beam temporary support 7-2 is erected. The lower part of the n+1 layer of steel beam temporary support 7-2 is welded to the floor steel beam 6-1. The n-layer hanger interlayer main section 402 is installed on the hanger connection section on the n-layer floor steel beam 6-1. The two are connected by bolts installed on the lower connecting ear plate 802 and tightened. The upper connecting ear plate 801 is not installed first.

[0061] Step 4: See Figure 6 As shown, the n+1 floor steel beam 6-2 is installed. Before hoisting, a connecting section of the hanger rod extending from the top and bottom surfaces of the steel beam 6-2 is pre-installed. The top end 403 of this connecting section extends beyond the top surface of the floor steel beam, and the bottom end 401 extends beyond the bottom surface of the floor steel beam. The bottom end 401 of the connecting section of the hanger rod on the n+1 floor steel beam 6-2 is not connected to the main section 402 of the hanger rod between floors in the nth floor. At the same time, the connection node 9-2 between the n+1 floor steel beam 6-2 and the core tube 1 is connected using ordinary bolts 902, and the weld 904 is not welded for the time being. That is, the n+1 floor steel beam 6-2 and the connecting steel beams on the core tube 1 that connect to the n+1 floor steel beam 6-2 are temporarily connected by connecting steel plates and ordinary bolts 902, while the joint position between the connecting steel beams of the n+1 floor steel beam 6-2 is not welded for the time being.

[0062] Step 5: See Figure 7 As shown, for each floor below the cantilever steel truss where floor steel beams 6-2 need to be installed, the installation of all floor steel beams 6-2 and hanger segments below the truss is completed in the same construction method as in steps 3 and 4 as in step n+1, following the order from bottom to top.

[0063] It should be noted that when repeating the construction method of floor n+1 in steps 3 and 4 for other floors n+2 to n+a, the corresponding floor numbers need to be adjusted accordingly.

[0064] Step 6: See Figure 8 As shown, after all the floor steel beams on all floors have been installed, temporary truss supports 7-4 are erected on the foundation of the top floor steel beam temporary supports and the floor steel beams.

[0065] Step 7: See Figure 9 As shown, a cantilever steel truss is installed under the support of temporary truss support 7-4. Specifically, the lower chord, web members, and upper chord of the top-level truss need to be installed and welded. Corresponding truss hanging nodes 3 need to be set on the cantilever steel truss, and the nodes have hanging rods 301.

[0066] Step 8: See Figure 10As shown, after the cantilever steel truss is installed, the temporary truss support 7-4 is removed to complete the unloading of the cantilever steel truss.

[0067] Step 9: See Figure 11 As shown, a supplementary section 303 of a hanger rod is installed on the truss suspension node 3 at the bottom of the cantilever steel truss. The top end of the supplementary section 303 is connected and fixed to the hanger rod suspension component 301 on the truss suspension node 3 using a pin 302. The bottom end of the supplementary section 303 is welded and fixed to the top end 403 of the hanger rod connection section fixedly installed on the n+a floor steel beam 6-3. In addition, the original ordinary bolts 902 are replaced with high-strength bolts 903 at the connection node 9-3 between the n+a floor steel beam 6-3 and the core tube 1. At the same time, the butt joint between the n+a floor steel beam 6-3 and the connecting steel beam on the core tube 1 is welded to form a weld 904.

[0068] Step 10: See Figure 12 As shown, remove the temporary support 7-3 for the steel beam of floor n+a, completing the unloading of the floor n+a structure. Then, use the upper connecting plate 801 to fix the bottom end 401 of the hanger connection section fixed on the floor steel beam 6-3 of floor n+a to the main hanger section 402 of the floor below (floor n+a-1). Next, weld the bottom end 401 and the main hanger section 402 between the floor steel beam 6-3 of floor n+a and the floor steel beam 6-4 of floor n+a-1, and the top end 403 of the hanger connection section. After welding, remove the existing... The welding positions include the lower butt joint plate 801 and the upper butt joint plate 802. Finally, the connection node 9-4 between the n+a-1 floor steel beam 6-4 and the core tube 1 is reinforced by replacing the original ordinary bolts 902 between the n+a-1 floor steel beam 6-4 and the connecting steel beam on the core tube with high-strength bolts 903. Simultaneously, the butt joint between the n+a-1 floor steel beam 6-4 and the connecting steel beam on the core tube 1 is welded to form weld 904. This allows the n+a floor steel beam 6-3 to form a suspension system with the cantilever steel truss.

[0069] Step 11: See Figure 13 As shown, for the remaining floors where the floor steel beams 6 are installed, i.e., floors n to n+a-1, construction is carried out sequentially from top to bottom. For each construction floor, the construction method of floor n+a in steps 10 and 11 is followed, unloading the floor steel beams layer by layer and forming a suspension system with the cantilever steel truss, until the bottom floor steel beam 6-1 on the nth floor is reached. It should be noted that there are no hangers below the floor steel beam 6-1 on the nth floor, so no hanger construction work is required.

[0070] It should be noted that when repeating the construction method for floor n+a in steps 10 and 11 for other floors n to n+a-1, the corresponding floor numbers need to be adjusted accordingly.

[0071] Step 12: See Figure 14 As shown, after the steel structure construction of all floors is completed, the concrete floor slabs can be poured and the curtain walls of each floor can be installed on the foundation of the steel beams 6 on each floor, following the subsequent construction organization sequence and the construction sequence from top to bottom.

[0072] In addition, it should be noted that the construction method of the present invention is not only applicable to structures with the hanging node being the pin 302, but can also be used for other types of suspension structures.

[0073] Furthermore, in the traditional bottom-up construction process of suspended structures, the elevation control of each floor is generally achieved through construction simulation analysis and calculation using software. After determining the final deflection of the steel beams at the suspension node positions on each floor, the steel beams of each floor are pre-cambered during construction. However, this method has problems: the hangers of traditional suspended structures are vertical, and their structural deformation differs from that of inclined hanger suspension structures. Therefore, the pre-cambering method is not entirely applicable to inclined hanger suspension structures. Since the hangers only bear tensile force and not compressive force, during the unloading process from top to bottom, it is necessary to first remove the temporary supports of that floor before installing or connecting the inclined hangers. When the temporary supports are unloaded, the upper structure will deform first, resulting in a reduction in the floor height. This leads to a relatively long prefabricated hanger length, causing installation difficulties.

[0074] Therefore, in another embodiment of the present invention, a construction method for compensating for deformation of inclined suspended structures is further proposed for the construction method of temporary support and bottom-up construction of inclined suspended structures, so as to optimize the calculation method of the installation elevation of steel beams on each floor and reduce the impact of structural deformation on the installation of inclined suspension rods.

[0075] In the pressure-free construction method for suspending inclined hangers under cantilever steel trusses provided in the foregoing embodiments of the present invention, the construction process of the inclined hanger suspension structure is as follows: a support frame is erected from the ground, the steel structure is installed from bottom to top, and after all the floor steel beams and top cantilever trusses are installed, the load is unloaded layer by layer from top to bottom, while the inclined hangers are installed and connected. After unloading, the floor deck is poured and the curtain wall is installed. Therefore, based on this construction method, as can be seen from the aforementioned floor number definition, the floor number of the lowest floor of the inclined hanger suspension structure is n, the total number of floors below the cantilever steel truss in the inclined hanger suspension structure is a (a = 0, 1, 2, ...); the design elevation of the hanger node position (top surface of the lower chord) of the cantilever truss floor is denoted as H, and the floor height of any k-th floor is h. k (k = 1, 2, ...). This invention further requires pre-construction simulation using software such as Midas Gen to determine certain parameters through calculation, specifically including:

[0076] 1) Calculate the vertical displacement of the lower chord hanger node (top surface of the lower chord member) of the cantilever steel truss under its own weight load, denoted as γ.

[0077] 2) During the unloading process, after each floor forms a suspension system with the cantilever steel truss, the increase in vertical displacement at the beam hanger node (top surface of the steel beam) on each floor under its own weight is denoted as A. i , (i≥n).

[0078] 3) After all floors have been poured with concrete, the increase in vertical displacement at the lower chord hanger node of the cantilever steel truss is recorded as B.

[0079] 4) After the curtain wall is installed, the increase in vertical deflection at the lower chord hanger node of the cantilever truss is denoted as C.

[0080] Based on the calculation results obtained from the above construction process simulation, it is necessary to control the construction elevation of the lower chord hanger nodes of the cantilever steel truss during construction. Specifically,

[0081] During construction, the construction elevation of the lower chord hanger node of the cantilever steel truss must be controlled as follows:

[0082]

[0083] After the cantilever steel truss is unloaded, the deflection γ under the truss's self-weight load does not affect the elevation of the lower floor. Therefore: the construction elevation of the steel beams on floor n+a. Construction elevation of steel beams on floor n+a-1 Similarly, the formula for calculating the construction elevation of the steel beam on any floor ith (i = n, n+1, ..., n+a) is:

[0084]

[0085] Therefore, the above method clarifies the calculation formula for the floor elevation of the suspended structure, and eliminates the influence of structural deformation on the installation of the suspension rods during the unloading process of the suspended structure by controlling the floor beam elevation.

[0086] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all technical solutions obtained through equivalent substitution or transformation fall within the protection scope of the present invention.

Claims

1. A pressure-free construction method for suspending inclined rods under a cantilever steel truss, characterized in that, The inclined hangers used to connect the floor steel structure are pre-fabricated in sections at the factory. The inclined hangers are divided into a main inter-floor section and a connecting section. The main inter-floor section forms the main body of the inclined hanger between floors. The connecting section is fixed to the floor steel beam, with its top end extending from the top surface of the floor steel beam and its bottom end extending from the bottom surface of the floor steel beam respectively used to connect the main inter-floor sections of the hangers between the upper and lower floors. The construction method includes: S1. Temporary steel beam supports are erected on the ground around the constructed core tube, and the lowest floor steel beam of the suspension structure is installed under the support of the temporary steel beam supports. The connection nodes between the floor steel beam and the core tube are temporarily connected with ordinary bolts and the welds are not welded for the time being. The hanger connection section extending from the top surface of the steel beam is fixedly installed on the lowest floor steel beam. S2. For other floors on the core tube that require the installation of floor steel beams, construction shall proceed sequentially from bottom to top. For each construction floor, temporary supports for the steel beams required for the current construction floor shall be erected first on the foundation of the temporary supports for the steel beams of the floors below and the floor steel beams. Then, a main inter-floor section of the hanger rod shall be fixedly connected to the hanger rod connecting section fixedly installed on the floor steel beams of the floors below by means of a lower connecting lug plate. The floor steel beams corresponding to the current construction floor shall be installed under the support of the temporary supports for the steel beams. The connection nodes between the floor steel beams corresponding to the current construction floor and the core tube shall be temporarily connected using ordinary bolts, and the welds shall not be welded for the time being. Hanger rod connecting sections extending from the top and bottom surfaces of the steel beams shall be fixedly installed on the floor steel beams corresponding to the current construction floor. The bottom of the hanger rod connecting section shall only be connected to the main inter-floor section of the hanger rod below, but the lower connecting lug plate shall not be installed for the time being. S3. After all the floor steel beams on all floors have been installed, erect temporary truss supports on the foundation of the top floor steel beam temporary supports and floor steel beams, and install cantilever steel trusses under the support of the temporary truss supports. After the cantilever steel trusses are installed, remove the temporary truss supports. S4. Suspend and fix a supplementary section of the hanger rod at the truss hanging node at the bottom of the cantilever steel truss, and weld the bottom of the supplementary section of the hanger rod to the top of the hanger rod connection section fixedly installed on the top floor steel beam; at the same time, replace the ordinary bolts in the connection node between the top floor steel beam and the core tube with high-strength bolts and weld the weld. S5. For the remaining floors where floor steel beams are installed, construction shall proceed sequentially from top to bottom, so that the floor steel beams form a suspension system with the cantilever steel truss layer by layer. For each construction floor, the temporary supports of the steel beams below the floor steel beams of the construction floor must be removed first. Except for the bottom floor, the bottom of the connecting section of the hanger fixed on the floor steel beam of the current construction floor must be fixed to the main section of the hanger between the floors below through the upper connecting lugs. Then, the joint of the three sections of hanger between the current construction floor and the floors below is welded and fixed, and the upper and lower connecting lugs at the weld joint are removed. At the same time, the ordinary bolts in the connection nodes between the floor steel beams and the core tube corresponding to the current construction floor are replaced with high-strength bolts, and the welds are welded. Before construction, a construction process simulation must be conducted to determine the vertical displacement of the lower chord hanger node of the cantilever steel truss under its own weight load. The increase in vertical displacement at the top surface of the floor steel beams under self-weight load after any i-th floor forms a suspension system with the cantilever steel truss. The increase in vertical displacement at the lower chord hanger node of the cantilever steel truss after all floor concrete slabs have been poured. The increase in vertical deflection at the lower chord hanger node of the cantilever steel truss after the curtain wall installation is completed. ; During construction, it is necessary to control the construction elevation of the lower chord hanger node of the cantilever steel truss. At the same time, it is necessary to control the construction elevation of the steel beams on the i-th floor to be [value missing]. In the formula, H is the design elevation of the lower chord hanger node of the cantilever steel truss. Let i be the floor height of the kth floor, n be the floor number of the bottom layer of the inclined suspension structure, and a be the total number of floors below the cantilever steel truss in the inclined suspension structure, i = n, n+1, ..., n+a.

2. The construction method for suspending inclined rods under a cantilever steel truss without pressure during construction, as described in claim 1, is characterized in that... The construction progress of the core tube needs to be at least 1 to 2 floors ahead of the installation progress of the floor steel beams.

3. The construction method for suspending inclined rods under a cantilever steel truss without pressure during construction, as described in claim 1, is characterized in that... The temporary supports for the steel beams are constructed using tower crane standard sections, square tubes, H-beams, or lattice columns.

4. The construction method for suspending inclined rods under a cantilever steel truss without pressure during construction, as described in claim 1, is characterized in that... The hoisting equipment used for lifting components during construction includes truck cranes, tower cranes, and crawler cranes.

5. The construction method for suspending inclined rods under a cantilever steel truss without pressure during construction, as described in claim 1, is characterized in that... The truss suspension node and the rear section of the suspension rod are suspended and fixed by a pin.

6. The construction method for suspending inclined rods under a cantilever steel truss without pressure during construction, as described in claim 1, is characterized in that... The upper and lower connecting lugs are temporarily connected to the two connecting rod sections by bolts. Once the connecting rod sections are welded and fixed, they can be removed.

7. The construction method for suspending inclined rods under a cantilever steel truss as described in claim 1, characterized in that, After the steel structure construction of all floors is completed, the concrete floor slabs are poured on the foundation of the steel beams on each floor in a top-down construction sequence.

8. The construction method for suspending inclined rods under a cantilever steel truss without pressure during construction, as described in claim 1, is characterized in that... After the concrete floor slabs of all floors have been poured, the curtain wall installation will be carried out on each floor.

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