Construction method suitable for prestressed spring layer circular tube steel-concrete arch structure

Abstract

The invention relates to the technical field of building construction, and discloses a construction method suitable for a prestressed spring layer circular tube steel-concrete arch structure, duct grouting is performed after the structure is closed, a stable and reliable bonded prestressed system is formed, and the structural integrity and durability are enhanced; by combining a construction mechanical model and construction monitoring data, prestress loss is dynamically corrected, whole-process management of prestress control is achieved, construction adaptability and engineering quality are improved, the stress state and health condition of a structure in the construction process can be mastered easily by scientifically formulating a construction sequence and arranging structure monitoring points, and the construction efficiency is improved. And structural hidden dangers such as local excessive anti-arching or advanced cracking caused by non-uniform prestress distribution are prevented. The method has the advantages of being high in structural safety, controllable in construction process, uniform in prestress distribution, stable and reliable in structural performance and the like, and is suitable for engineering construction of the spring-layer circular tube steel-concrete arch structure under the complex stress condition.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, specifically to a construction method applicable to prestressed multi-layer circular tube steel-concrete arch frame structure. Background Technology

[0002] With the continuous development of building engineering technology, prestressed concrete structures have been widely used in large-span and complex structural building projects due to their excellent load-bearing performance and high structural efficiency. Especially in public buildings with large space requirements such as museums and exhibition centers, the use of prestressing technology can effectively reduce the structural cross-section, improve structural stiffness and durability, thereby meeting the dual requirements of building space and function.

[0003] In practical engineering projects, such as the Shenzhen Museum, which are typically large-span and structurally complex, the main structural form often adopts a large-span circular arch structure, supplemented by various irregular beam-slab combination systems. During construction, the large directional thrust generated by the arch structure is concentrated on the lower chord concrete floor slab and beams, which easily leads to cracking risks, thus affecting the overall safety and service life of the structure. At the same time, to achieve the expected stress state in the structural design, the prestressing tendons need to be precisely tensioned. However, due to limitations in on-site construction conditions and control methods, the actual tension force often deviates from the design value, making it difficult to meet the expected requirements for structural deformation control and load-bearing capacity.

[0004] While prestressed technology has been widely adopted in civil engineering, the control of prestress loss during construction remains a significant challenge. Prestress loss is typically caused by a combination of factors, including concrete shrinkage, creep, steel reinforcement relaxation, anchor deformation, and friction effects. It exhibits complex time-varying characteristics and spatial heterogeneity, and failure to effectively control this loss directly impacts the structure's load-bearing capacity and safety margin. Furthermore, existing construction methods for large-span prestressed concrete structures still have shortcomings in tensioning processes, construction sequence, and structural response control. This leads to uneven prestress distribution, excessive local camber, or premature cracking during actual construction, severely restricting the structural performance. Summary of the Invention

[0005] In view of this, in order to solve the above-mentioned technical problems, the present invention provides a construction method applicable to prestressed multi-layer circular tube steel-concrete arch frame structure, so as to solve the problems of uneven prestress distribution, excessive local arching or premature cracking in the construction of existing circular tube steel-concrete arch structures.

[0006] The technical solution is as follows:

[0007] This invention provides a construction method applicable to prestressed multi-layer circular tube steel-concrete arch frame structures, comprising the following steps:

[0008] Before pouring structural concrete, corrugated pipes are pre-embedded according to design requirements to form ducts for passing prestressed tendons.

[0009] The steel strand is threaded into the duct using a mechanical pushing method, and anchors are installed at both ends of the duct.

[0010] Once the concrete strength reaches 80% or more of the design strength, the steel strands are symmetrically and uniformly tensioned through the anchorage, and the tension force and elongation are monitored by sensors.

[0011] After the structure is assembled, the ducts of the corrugated pipe are grouted to ensure that the grout fills the ducts and forms a stable bonded prestressed system.

[0012] Based on the construction mechanics model and real-time construction monitoring data, the prestress loss of the prestressed system is calculated and dynamically corrected throughout the entire process.

[0013] The construction sequence is determined based on the structural stress characteristics, and monitoring points are set up at the construction structural nodes for structural health monitoring.

[0014] It has the following advantages:

[0015] This invention provides a construction method applicable to prestressed multi-layer circular tube steel-concrete arch frame structures. By pre-embedding corrugated pipes before concrete pouring to form tendon-passing ducts, the accuracy of prestressing tendon placement and the operability of construction are ensured. A mechanical pushing method is used to pass the steel strands, combined with anchorages and a sensor system to implement symmetrical and uniform tensioning, significantly improving the accuracy of prestress application and the controllability of the construction process. By real-time monitoring of tension force and elongation, and implementing tensioning when the concrete reaches more than 80% of its design strength, tension deviations caused by structural deformation or insufficient material properties are effectively reduced. Grouting of the ducts after the structure is closed forms a stable and reliable bonded prestressed system, enhancing the overall integrity and durability of the structure. Combining construction mechanics models and construction monitoring data, prestress loss is dynamically corrected, achieving full-process management of prestress control and improving construction adaptability and project quality. Furthermore, by scientifically formulating the construction sequence and setting up structural monitoring points, it is helpful to understand the stress state and health status of the structure during construction, preventing structural hazards such as excessive local arching or premature cracking caused by uneven prestress distribution.

[0016] According to some embodiments of the present invention, the tension control stress is taken as 0.6 to 0.7 times the tensile strength of the steel strand.

[0017] According to some embodiments of the present invention, grouting is performed on the channels of the corrugated pipe using a vacuum-assisted method. A grouting port and a vacuum extraction port are connected to both ends of the corrugated pipe, respectively. After a negative pressure is formed in the channels, a well-stirred cement-based grout is injected until the grout overflows from the other end.

[0018] According to some embodiments of the present invention, prestress losses include elastic compression losses, duct wall friction losses, anchor deformation losses, concrete shrinkage and creep losses, and steel strand relaxation losses.

[0019] According to some embodiments of the present invention, the construction sequence includes constructing the arch foot nodes in sequence, constructing the lower chord tie beam from both ends to the middle, and reserving expansion joints and post-pouring strips.

[0020] According to some embodiments of the present invention, the concrete used is C40 self-compacting concrete, the concrete strength reaches ≥80%, the concrete age is ≥15 days, and prestressing is performed.

[0021] According to some embodiments of the present invention, the corrugated pipe is a steel corrugated pipe with an inner diameter of 50 to 70 mm and a length of 100 meters or more. During the threading process, the steel strands are fed into the channels of the corrugated pipe by a mechanical continuous pushing method.

[0022] According to some embodiments of the present invention, multiple stress and deformation monitoring points are set up in the lower chord tie beam arch frame with five or more floors, and data are exchanged with the structural health monitoring system to form a real-time feedback and adjustment mechanism. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a flowchart illustrating a construction method for a prestressed multi-layered circular tube steel-concrete arch frame structure, as provided in some embodiments of the present invention.

[0025] Figure 2 This is a structural diagram of the four main steel columns in the structural installation provided in some embodiments of the present invention;

[0026] Figure 3 This is an installation structure diagram of the arch foot node in the structural installation provided in some embodiments of the present invention;

[0027] Figure 4 This is an installation structure diagram of the lower chord tie beam provided in some embodiments of the present invention;

[0028] Figure 5 This is a structural diagram of mortar injection into the lower chord tie beam during structural installation provided in some embodiments of the present invention;

[0029] Figure 6This is an installation structure diagram of the steel bracket for installing the supporting arch rib in some embodiments of the present invention.

[0030] Figure 7 This is an installation structure diagram of the sixth-layer arch foot node in the structural installation provided in some embodiments of the present invention;

[0031] Figure 8 This is a structural diagram of the installation of the sixth-floor lower chord tie beam in some embodiments of the present invention.

[0032] Figure 9 This is an installation structure diagram of the seventh-layer installation support in some embodiments of the present invention;

[0033] Figure 10 This is a structural diagram of the installation of the seventh arch rib in some embodiments of the present invention;

[0034] Figure 11 This is a complete structural diagram of the arch frame structure provided in some embodiments of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Connecting part; 101. Screw; 102. Screw hole. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0040] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0041] Reference Figure 1 As shown, the present invention provides a construction method suitable for prestressed multi-layer circular tube steel-concrete arch frame structures, comprising the following steps:

[0042] Before pouring structural concrete, corrugated pipes are pre-embedded according to design requirements to form ducts for passing prestressed tendons.

[0043] The steel strand is threaded into the duct using a mechanical pushing method, and anchors are installed at both ends of the strand.

[0044] Once the concrete strength reaches 80% or more of the design strength, the steel strands are tensioned symmetrically and uniformly using anchors, and the tension force and elongation are monitored by sensors.

[0045] After the structure is assembled, the ducts of the corrugated pipe are grouted to ensure that the grout fills the ducts and forms a stable bonded prestressed system.

[0046] Based on the construction mechanics model and real-time construction monitoring data, the prestress loss of the prestressed system is calculated and dynamically corrected throughout the entire process.

[0047] The construction sequence is determined based on the structural stress characteristics, and monitoring points are set up at the construction structural nodes for structural health monitoring.

[0048] Specifically, this invention provides a construction method applicable to prestressed multi-layer circular tube steel-concrete arch frame structures. By pre-embedding corrugated pipes before concrete pouring to form tendon-passing ducts, the accuracy of prestressing tendon placement and the operability of construction are ensured. A mechanical pushing method is used to pass the steel strands, combined with anchorages and a sensor system to implement symmetrical and uniform tensioning, significantly improving the accuracy of prestress application and the controllability of the construction process. By real-time monitoring of tension force and elongation, and implementing tensioning when the concrete reaches more than 80% of its design strength, tension deviations caused by structural deformation or insufficient material properties are effectively reduced. Grouting of the ducts after the structure is closed forms a stable and reliable bonded prestressed system, enhancing the overall integrity and durability of the structure. Combining construction mechanics models and construction monitoring data, prestress loss is dynamically corrected, achieving full-process management of prestress control and improving construction adaptability and project quality. Furthermore, by scientifically formulating the construction sequence and setting up structural monitoring points, it is helpful to understand the stress state and health status of the structure during construction, preventing structural hazards such as excessive local arching or premature cracking caused by uneven prestress distribution. The method of the present invention has the advantages of high structural safety, controllable construction process, uniform prestress distribution, and stable and reliable structural performance. It is suitable for engineering construction of multi-layer circular tube steel-concrete arch frame structures under complex stress conditions.

[0049] In this embodiment, the arch frame structure is a large-span, multi-level circular tube steel-concrete arch frame structure spanning five floors to the roof, with a span of 94.34 meters. The lower chord of the arch frame is equipped with 12 bundles of TW15-37 type internal prestressed steel strands, each bundle being 101.3 meters long, and is constructed using a bonded post-tensioning method.

[0050] The construction process mainly includes the structural installation process and the prestressed system construction process. The structural installation process is as follows:

[0051] Reference Figure 2 and Figure 3 As shown, after the construction of the four main steel columns is completed, a temporary support system for the arch frame installation is installed. This support system is set above the fourth-floor slab to provide a supporting foundation for the subsequent hoisting of the arch ribs. After the temporary support system on the fourth-floor slab is in place, the "arch foot nodes" at the starting end of the arch frame are laid out and connected to provide rigid anchoring conditions for the lower end of the arch frame and to meet the requirements for axis and elevation control.

[0052] Understandably, during the foundation construction phase, steel components connecting the arch foot nodes are pre-embedded, and spatial positioning is achieved using laser total stations or 3D coordinate control technology to ensure that the axis of the arch foot nodes is aligned with the subsequent installation of the arch ribs, laying the foundation for structural precision control. The arch frame structure is manufactured in segments and assembled on-site using hoisting techniques.

[0053] Reference Figure 4As shown, lower chord tie beams are symmetrically installed from both sides of the structure at a height of five stories, providing a foundation for subsequent arch rib connections. Corrugated pipes are embedded within these beams, with pre-set cable-passing channels. After the steel tie beams are installed, C40 self-compacting concrete is poured to enhance the structural integrity and crack resistance, forming a steel-concrete composite beam. Following concrete pouring, structural monitoring points are deployed to monitor the stress state and health of the structure during construction, preventing structural hazards such as excessive localized arching or premature cracking due to uneven prestress distribution.

[0054] Understandably, installation proceeds symmetrically from both ends towards the center during construction. Each arch rib is assembled on the ground and then hoisted to its designated position as a whole, where it is welded or bolted to the preceding segment. A temporary support system is also in place to ensure structural stability.

[0055] Reference Figure 5 As shown, tensioning is initiated after the concrete reaches its design strength. The tensioning method is simultaneous symmetrical tensioning at both ends, with the tension control stress being 0.6 to 0.7 times the tensile strength of the steel strands. After tensioning, vacuum-assisted grouting is used to grout the corrugated pipe. The joint is sealed after the grout overflows from the other end, ensuring the formation of a bonded prestressed system and achieving a dense seal.

[0056] Reference Figure 6 As shown, steel supports for the arch ribs are installed on the fifth-floor beam structure, and segmental connecting columns are laid out to position the first arch rib and arch column components. Starting from the arch foot node, the first arch rib component is installed and connected to the lower chord tie beam and segmental columns to ensure arching accuracy and angle. The main beam components for the sixth floor are then laid out upwards, and the installation of the second and third arch rib segments begins, assembling the modules. Figure 7 and Figure 8 As shown.

[0057] Repeat the above steps to install support nodes and positioning columns for the arch ribs on the sixth-floor main beam, ensuring the construction accuracy of the upper arch ribs. Continue installing the second and third sections of the arch ribs to the seventh floor, forming part of the arched outline of the main structure. Geometric deviations need to be monitored during installation. Complete the hoisting of the arch rib sections between the sixth and seventh floors, and connect the node plates between the arch ribs to form a continuous load-bearing arch ring.

[0058] The fifth and sixth arch ribs are extended to the fifth-floor roof, and segmental columns are installed at the apex to provide structural support for the final arch rib section. After the final arch rib section is hoisted and the arch is closed, the arched structure is formed, and the main arch frame structure is fully installed. Figure 9 , Figure 10 and Figure 11 As shown.

[0059] After the two arch sections are hoisted to their designated positions, the middle closure section is hoisted. An adjustment length is reserved at the closure joint, and the section is precisely adjusted to within the design assembly error range using a hydraulic jacking device before connection is completed, forming a complete spatial arch structure load-bearing system.

[0060] After the arch frame is installed to the fifth floor, the lower chord steel-concrete composite tie beam is installed simultaneously. Corrugated pipes for arranging prestressed steel strands are pre-embedded within the precast box girder section, along with anchorage slots and reserved positions for subsequent monitoring systems. Corrugated pipes are accurately pre-embedded within the steel shell of the lower chord tie beam according to design requirements. The curvature, length, and interface angle of the metal corrugated pipes are strictly controlled according to the design. After the corrugated pipes are installed, a pipe-clearing instrument is used to check the through-holes, ensuring continuous and unobstructed prestressed ducts.

[0061] In some embodiments of the present invention, the tension control stress is taken as 0.6 to 0.7 times the tensile strength of the steel strand. This range of 0.6 to 0.7 times the tensile strength of the steel strand is beneficial for ensuring structural safety while achieving full utilization and reasonable distribution of prestress. The selection of this stress range takes into account the material properties of the prestressing tendons, safety redundancy, and adaptability to the construction environment. It effectively avoids excessive tension stress leading to local yielding of the steel strand or anchorage failure, and also prevents insufficient prestress compensation due to excessively low stress, which could make it difficult to suppress early concrete cracking or insufficient structural camber. Specifically, controlling the tension stress within the range of 0.6 to 0.7 times the tensile strength not only improves the controllability and repeatability of the tensioning process, but also allows for more refined prestress loss compensation and tension force distribution adjustment, taking into account the structural stress characteristics during construction, the time differences in concrete strength development and creep shrinkage effects. Furthermore, this control range facilitates flexible adjustment of the tension force on-site based on monitoring data, making it suitable for high-performance building structural systems with complex geometries, large spans, and multi-story structures, thereby improving the quality stability and construction adaptability of the project.

[0062] After the arch frame structure is closed, TW15-37 steel strands are threaded one by one into the pre-embedded corrugated pipes using a mechanical pushing method. The steel strands are 101.3 meters long. During the threading process, the threading force, feeding speed, and path must be controlled to prevent twisting, jamming, and other defects that affect prestressing performance. After threading, anchors are installed at both ends, and the initial elongation value is calibrated. After the steel strands are threaded, C40 self-compacting concrete is poured into the lower chord tie beam box girder to ensure dense filling and a good bond with the steel shell structure. The curing period is no less than 15 days, and the concrete strength must reach more than 80% of the design strength before tensioning operations can proceed.

[0063] In some embodiments of the present invention, a vacuum-assisted method is used to grout the channels of the corrugated pipe. A grouting port and a vacuum extraction port are connected to both ends of the corrugated pipe, respectively. After a negative pressure is formed in the channel, a well-stirred cement-based grout is injected until the grout overflows from the other end.

[0064] Specifically, by setting grouting ports and vacuum extraction ports at both ends of the corrugated pipe, and injecting uniformly mixed cement-based grout after negative pressure is formed, not only is the filling density and construction reliability of the grouting process improved, but the overall performance and long-term durability of the bonded prestressed system are also significantly enhanced.

[0065] According to some embodiments of the present invention, prestress losses include elastic compression losses, duct wall friction losses, anchor deformation losses, concrete shrinkage and creep losses, and steel strand relaxation losses.

[0066] Specifically, considering elastic compression loss effectively compensates for stress attenuation caused by the elastic deformation of concrete in the initial stage of stress, helping to accurately set the initial tension stress value. Based on the bellows geometry, strand length, and curvature changes, the force difference between the tensioning end and the free end can be accurately estimated, avoiding uneven tension force distribution. Calculating anchorage deformation loss helps compensate for the significant stress loss caused by anchorage locking, strand retraction, and other structural details, improving the precision control of the anchoring system. Combining concrete shrinkage and creep loss analysis fully considers the prestress weakening caused by volume changes in concrete during long-term service, improving the long-term structural stability. Evaluating strand relaxation loss, especially for high-strength prestressed steel, corrects the stress release pattern of the material during sustained stress, ensuring the ability to maintain the design stress throughout the structure's service life.

[0067] In some embodiments of the present invention, the construction sequence includes sequentially constructing the arch foot nodes, constructing the lower chord tie beams from both ends toward the middle, and reserving expansion joints and post-pouring strips.

[0068] It is understandable that tensioning when the concrete strength reaches more than 80% of the design value can effectively prevent tensile cracking or crushing failure caused by early tensioning, ensuring the structural safety. Controlling the period to 15 days or more helps the concrete complete its initial shrinkage and thermal expansion stages, reducing uneven deformation caused by constraints within the structure and improving the stability after prestressing. The use of self-compacting concrete improves molding quality, achieving high density in complex components without strong vibration, and enhancing the mechanical properties and impermeability of the area surrounding the prestressing ducts. Precise matching of tensioning timing with concrete properties makes the tension force and structural deformation response more predictable, helping to improve the accuracy of elongation measurement and tension force control, and reducing construction errors.

[0069] In some embodiments of the present invention, the corrugated pipe is a steel corrugated pipe with an inner diameter of 50 to 70 mm and a length of 100 meters or more. During the threading process, the steel strands are fed into the channels of the corrugated pipe by a mechanical continuous pushing method.

[0070] In some embodiments of the present invention, multiple stress and deformation monitoring points are set up on the lower chord tie beam arch frame with five or more floors, and data are exchanged with the structural health monitoring system to form a real-time feedback and adjustment mechanism.

[0071] Specifically, monitoring points for stress, displacement, and deflection are set up at key structural components, such as the lower chord tension beam. This allows for real-time acquisition of the actual stress state along the tension force transmission path, identifying localized abnormal responses caused by prestress loss, changes in component stiffness, or temperature stress. After integrating the monitoring data into the structural health monitoring system, it can be compared in real-time with the initial construction mechanics model, dynamically correcting model parameters. This enables prestress loss feedback, tensioning sequence optimization, and structural anti-camber control based on measured data, significantly improving the accuracy and strain control capabilities of the construction process.

[0072] The real-time monitoring system can issue timely warning signals when the arch frame structure exceeds limits due to tension deviation, nonlinear deformation, or time-varying effects. This guides on-site technicians to take corrective measures, preventing early cracking or arch imbalance and ensuring the quality of structural construction and service safety. By establishing a long-term connection mechanism between monitoring points and the health system, the monitoring data can be used not only for construction-phase control but also extended to structural condition assessment during the service life, promoting the transformation from "construction quality control" to "life-cycle performance management."

[0073] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A construction method applicable to prestressed multi-layer circular tube steel-concrete arch frame structures, characterized in that, Includes the following steps: Before pouring structural concrete, corrugated pipes are pre-embedded according to design requirements to form ducts for passing prestressed tendons. The steel strand is threaded into the duct using a mechanical pushing method, and anchors are installed at both ends of the duct. Once the concrete strength reaches 80% or more of the design strength, the steel strands are symmetrically and uniformly tensioned through the anchorage, and the tension force and elongation are monitored by sensors. After the structure is assembled, the ducts of the corrugated pipe are grouted to ensure that the grout fills the ducts and forms a stable bonded prestressed system. Based on the construction mechanics model and real-time construction monitoring data, the prestress loss of the prestressed system is calculated and dynamically corrected throughout the entire process. The construction sequence is determined based on the structural stress characteristics, and monitoring points are set up at the construction structural nodes for structural health monitoring.

2. The construction method for prestressed multi-layered circular tube steel-concrete arch frame structures according to claim 1, characterized in that, The tension control stress is taken as 0.6 to 0.7 times the tensile strength of the steel strand.

3. The construction method for prestressed multi-layered circular tube steel-concrete arch frame structures according to claim 2, characterized in that, The duct of the corrugated pipe is grouted using a vacuum-assisted method. A grouting port and a vacuum extraction port are connected to both ends of the corrugated pipe, respectively. After a negative pressure is formed in the duct, a well-stirred cement-based grout is injected until the grout overflows from the other end.

4. The construction method for prestressed multi-layered circular tube steel-concrete arch frame structures according to claim 1, characterized in that, Prestress losses include elastic compression losses, duct wall friction losses, anchor deformation losses, concrete shrinkage and creep losses, and steel strand relaxation losses.

5. The construction method for prestressed multi-layered circular tube steel-concrete arch frame structures according to claim 1, characterized in that, The construction sequence includes constructing the arch foot nodes in sequence, constructing the lower chord tie beams from both ends to the middle, and reserving expansion joints and post-pouring strips.

6. The construction method for prestressed multi-layered circular tube steel-concrete arch frame structures according to any one of claims 1-5, characterized in that, The concrete used is C40 self-compacting concrete, with a strength of ≥80% and an age of ≥15 days, and is prestressed.

7. The construction method for prestressed multi-layered circular tube steel-concrete arch frame structures according to any one of claims 1-5, characterized in that, The corrugated pipe is a steel corrugated pipe with an inner diameter of 50-70mm and a length of 100 meters or more. During the threading process, the steel strands are fed into the channels of the corrugated pipe one by one by mechanical continuous pushing.

8. The construction method for prestressed multi-layered circular tube steel-concrete arch frame structures according to any one of claims 1-5, characterized in that, Multiple stress and deformation monitoring points are set up in the lower chord tie beam arch frame of five stories and above, and data are exchanged with the structural health monitoring system to form a real-time feedback and adjustment mechanism.

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