A UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system and its design and construction method

Abstract

This invention discloses a post-tensioned, loosely bonded precast prestressed concrete frame structure system with UHPC (Ultra-High-Pressure Polymer) connection, comprising precast concrete upper columns, precast concrete lower columns, post-tensioned, loosely bonded precast prestressed concrete composite beams, UHPC node core areas, and composite slabs. The upper longitudinal main reinforcement extends from the bottom surface of the precast upper column, the lower longitudinal main reinforcement extends from the top surface of the precast lower column, and ordinary steel bars extend from the end face of the precast concrete beams, all directly anchored within the UHPC node core area. This structural system not only facilitates and expedites on-site construction, improving component installation efficiency, but also significantly reduces the anchorage length of the reinforcement, substantially reduces the amount of stirrups in the node core area, avoids reinforcement congestion in the node core area, reduces the component cross-sectional height, lightens the self-weight, and improves the component's crack resistance and self-healing performance, thereby improving the overall seismic performance of the frame structure. Post-tensioned, loosely bonded grouting offers the advantage of good durability and overcomes the disadvantage of incomplete grouting in post-tensioned bonding.

Description

Technical Field

[0001] This invention relates to the field of precast prestressed prefabricated building construction technology, and more specifically, to a UHPC-connected post-tensioned loosely bonded precast prestressed concrete frame structure system and its design and construction method. Background Technology

[0002] Cast-in-place structures suffer from numerous limitations, including low construction efficiency and high energy consumption, making them increasingly unsuitable for the demands of industrialized building development. Precast concrete structures, with their advantages of rapid construction, factory-produced components, reduced on-site wet work, and reduced environmental pollution, have become the future direction of industrialized building development. After years of development and promotion, precast concrete structures have been widely researched and used.

[0003] Precast concrete frame structures refer to structures where beams and columns are prefabricated in a prefabrication plant and transported to the construction site for connection to form an integral structure. Compared with cast-in-place concrete structures, they offer advantages such as faster construction speed, easier assurance of component quality, higher overall quality, less environmental pollution, reduced labor costs, and savings in formwork and supports, making them a structural form with a very broad prospect. For wet-connection precast concrete frame structures, easy-to-construct and effectively guaranteed joint construction methods are key to their widespread application. However, based on past earthquake disasters, precast structures have suffered more severe damage in earthquakes, making it difficult to achieve the same seismic performance as cast-in-place structures. To improve the integrity and reliability of joint connections in precast concrete frames and achieve or even surpass the seismic performance of cast-in-place concrete structures, prestressed technology and UHPC (Ultra High Performance Concrete) materials have been introduced into precast structures.

[0004] Post-tensioned bonded prestressed precast concrete structures are structures formed by assembling precast components together using tensioned prestressing tendons. They combine the characteristics of both post-tensioned bonded prestressed concrete structures and precast structures. The internal stress generated by prestressing in the concrete section can partially or completely offset the stress on the section under service loads, delaying crack initiation and improving the stiffness of the components. Upon unloading, cracks can partially or completely close, demonstrating good elastic recovery performance. Simultaneously, prestressed concrete can fully utilize the material strength of both the prestressing tendons and the concrete, reducing the structure's self-weight. Furthermore, the application of prestress contributes to improved performance and overall integrity of precast structures, promoting their application in large-span, heavy-load structures.

[0005] UHPC possesses excellent bonding properties, significantly reducing the anchorage length of reinforcing bars and strands. Its high strength reduces the amount of stirrups required in the joint core area. Using UHPC in the joint core area simplifies the construction and improves the overall frame integrity. Prestressed structures exhibit excellent load-bearing performance; applying UHPC to the joint core area creates a precast prestressed frame structure. In-depth research on this structure will facilitate the further promotion and application of precast prestressed concrete frame structures. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies and, by leveraging the superior performance of UHPC (Ultra-High-Pressure Concrete) structures, propose a UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system, along with its design and construction methods. This system combines three traditional structural elements: post-tensioned bonded prestressed structures, prefabricated structures, and composite structures, and utilizes high-performance UHPC materials to improve the seismic performance of precast precast concrete frame structures.

[0007] The advantages of this invention are mainly reflected in two aspects: the connection technology of precast concrete beam-column components and the rebar connection technology between components. Regarding component connection technology, beam-column components are connected through high-performance UHPC (Ultra-High-Pressure Polymer) to form a UHPC node core area, making it easier to meet the seismic fortification requirements of strong nodes and weak components, thereby improving the ductility of beam-column nodes and ultimately improving the seismic performance of the overall frame structure. Regarding rebar connection technology, the rebar between beam-column components only requires simple lap splices with very short lap lengths, significantly saving the fabrication time and on-site installation time of precast components. Therefore, the UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system and its design and construction methods proposed in this invention are in line with my country's green development strategy for building industrialization.

[0008] The technical problem solved by this invention can be achieved by the following technical solutions:

[0009] A UHPC-connected post-tensioned and loosely bonded precast prestressed concrete frame structure system includes a precast concrete upper column, a precast concrete lower column, a post-tensioned and loosely bonded precast prestressed concrete composite beam, a UHPC node core area, and a composite slab.

[0010] The precast concrete upper column is provided with upper longitudinal main reinforcement, and the precast concrete lower column is provided with lower longitudinal main reinforcement. The post-tensioned and bonded precast prestressed concrete composite beam is provided with a precast concrete beam, a beam composite layer and post-tensioned and bonded prestressing tendons. The bottom of the precast concrete beam is provided with ordinary steel bars, and the beam composite layer is provided with top continuous steel bars. The composite slab is composed of a precast concrete slab and a slab composite layer cast on the slab.

[0011] The upper longitudinal main reinforcement extends out of the bottom surface of the precast upper column and is directly anchored in the core area of ​​the UHPC node; the lower longitudinal main reinforcement extends out of the top surface of the precast lower column and is directly anchored in the core area of ​​the UHPC node; and the ordinary steel reinforcement extends out of the end face of the precast concrete beam and is directly anchored in the core area of ​​the UHPC node.

[0012] The slow-bonding prestressing tendons include straight, broken, and curved prestressing tendons;

[0013] The loosely bonded prestressed tendons in the core area of ​​the node can be bonded, bonded, partially bonded and unbonded, or unbonded.

[0014] Before pouring the beam composite layer, slab composite layer, and UHPC node core area, the post-tensioned, loosely bonded prestressed concrete composite beam undergoes construction verification calculations according to the force transmission mode adapted to ordinary concrete simply supported beams and bracing. After pouring the node core area, beam composite layer, and slab composite layer, once the concrete strength of the node and composite layer reaches the design requirements, the loosely bonded prestressing tendons are tensioned. After tensioning, the bracing is removed, and construction stage verification calculations are performed according to the frame beam method. During construction verification calculations, calculations are performed using unbonded prestressing tendons; under normal serviceability limit state and ultimate limit state, calculations are performed using bonded prestressing tendons.

[0015] Furthermore, the post-tensioned bonded precast prestressed concrete composite beam consists of a precast concrete beam, a beam composite layer, and post-tensioned bonded prestressing tendons.

[0016] Furthermore, the post-tensioned bonded prestressing tendons are pre-embedded in the precast concrete beam members according to the design position, and pass through the core area of ​​the UHPC node and extend beyond the core area of ​​the UHPC node at both ends. Clamps and anchors are fixedly installed at both ends, with one end set on the outside of the column and the other end set in the beam composite layer.

[0017] Furthermore, recessed grooves are provided on the bottom surface of the precast concrete upper column, the top surface of the precast concrete lower column, and the end face of the post-tensioned and loosely bonded precast prestressed concrete composite beam (U-shaped grooves can also be provided at the beam end, and structural shear reinforcement can be provided if necessary).

[0018] Furthermore, the precast concrete upper column is fixed in the corresponding position using reliable supports.

[0019] Furthermore, the stirrups in the precast concrete upper column, precast concrete lower column, and post-tensioned loosely bonded precast prestressed concrete composite beam are divided into a dense zone and a non-dense zone. The stirrups in the core area of ​​the UHPC node are arranged according to design requirements. The shear bearing capacity of the core area is calculated according to the diagonal compression member and truss model, and the steel fibers in the UHPC are considered to be equivalent to horizontal stirrups and vertical longitudinal bars, and their contribution to the shear resistance of the core area of ​​the node is considered. At the same time, the beneficial contribution of the loosely bonded prestressed tendons to the shear resistance of the node is also considered.

[0020] Furthermore, the top surface of the precast concrete beam and the precast concrete slab is provided with a rough surface layer.

[0021] This invention also provides a design method for the system, comprising the following steps:

[0022] Step 1: Design beams and columns according to existing specifications and invention patents;

[0023] Step 2: The seismic design of the joints should be carried out according to the following method, calculating the horizontal shear capacity V of the joints. jh :

[0024] The shear capacity of frame beam-column joints shall meet the following requirements:

[0025]

[0026] V jh =V ch +V sh +V fh +0.4N pe

[0027]

[0028] V sh =0.87·A sjh ·f yj

[0029] V jh ≤2.4(f cu ) 0.33 b c ·d c

[0030] f cu ≤70MPa

[0031]

[0032] V fh =ηλ f h b b c

[0033]

[0034] In the formula: A sjh —Area of ​​stirrups in the core area of ​​the node;

[0035] f yj —Design value of the yield strength of the stirrups in the core area of ​​the node;

[0036] ρ c —Column longitudinal reinforcement ratio;

[0037] d c —Effective height of the column;

[0038] d b —Effective height of the beam;

[0039] h c —Column height;

[0040] N pe —The effective prestressing resultant force of the prestressing tendons acting in the core area of ​​the node;

[0041] —Design axial compression ratio;

[0042] ρ — Column reinforcement ratio;

[0043] b b —Liang Kuan;

[0044] h b —Liang Gao;

[0045] f cu —Design value of compressive strength of concrete cube;

[0046] η—Effective coefficient of UHPC steel fiber;

[0047] l—Length of UHPC steel fibers;

[0048] d—Diameter of UHPC steel fibers;

[0049] V f —UHPC steel fiber volume content;

[0050] Step 3: At the intermediate nodes of the frame's intermediate floors, the upper longitudinal reinforcement of the frame beams should penetrate through the intermediate nodes; the diameter of each longitudinal reinforcement beam penetrating the central column, for seismic grades I, II, and III, when the column has a rectangular cross-section, should not exceed the smaller of 1 / 18 of the column's cross-sectional dimension in that direction and x; x is calculated using the following formula:

[0051] —Design axial compression ratio;

[0052] A s,top —The area of ​​the longitudinal reinforcement at the top of the beam. If the areas of the longitudinal reinforcement at the bottom of the left and right beams are not equal, then take the average value.

[0053] A s —Total area of ​​longitudinal reinforcement bars at the top and bottom of the beam.

[0054] A UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system includes the following steps:

[0055] Step 1: Fabricate precast concrete lower columns, precast concrete upper columns, precast concrete beams, and precast concrete slabs; among them, the longitudinal main reinforcement bars of the precast concrete lower columns and precast concrete upper columns must meet the anchorage length requirements when anchored into the core area of ​​the node; the ordinary reinforcement bars of the precast concrete beams must also meet the anchorage length requirements when anchored into the core area of ​​the node; when fabricating the precast concrete beams, the slow-bonded prestressing tendons are pre-embedded in the design position, and sufficient length is reserved at both ends to facilitate subsequent tensioning;

[0056] Step 2: After the precast components have cured, hoist the precast concrete lower column and install it on the foundation, and install a sufficient number of stirrups on the extended longitudinal main bars of the lower column;

[0057] Step 3: Hoist the precast concrete beam to the top of the precast concrete column, so that the bottom surface of the precast concrete beam is flush with the top surface of the precast concrete column, and place the end of the precast concrete beam on the precast concrete column and fix it with supports; wherein, the ordinary steel bars extending from the precast concrete beams on both sides are reasonably avoided and directly anchored in the core area of ​​the node according to the structural requirements.

[0058] Step 4: Hoist the precast concrete upper column to the top of the precast concrete lower column, and fix the precast concrete upper column in the corresponding position with reliable supports. At this time, tie the stirrups installed in Step 2 to the column longitudinal reinforcement. The longitudinal reinforcements extending from the precast concrete upper and lower columns should be reasonably avoided in the core area of ​​the node and directly anchored.

[0059] Step 5: Pass the top continuous steel bar through the stirrups reserved in the beam composite layer area and the core area of ​​the node and tie it. Then tie the pre-embedded and extended slow-bonding prestressed tendons in the precast concrete beam in the core area of ​​the node according to the design position. For the unbonded part of the node, a sleeve needs to be put on the slow-bonding tendon. Then pour the UHPC node core area and set the formwork so that the UHPC will not enter the beam composite layer.

[0060] Step 6: After the core area of ​​the UHPC node has cured to a sufficient strength, the precast concrete slab, composite slab, double T slab or secondary beam is hoisted onto the precast concrete beam and fixed.

[0061] Step 7: Pour the beam composite layer and slab composite layer;

[0062] Step 8: Tensioning the bonded prestressing tendons;

[0063] Step 9: Repeat the above production process to complete the tension-bonded prestressed concrete frame structure system.

[0064] Compared with the prior art, the advantages of the present invention are as follows:

[0065] 1. This invention combines precast concrete structures with post-tensioned, loosely bonded prestressed structures. It leverages the advantages of precast structures—convenient and rapid construction, high-quality build quality, energy efficiency, and environmental friendliness—while combining them with the advantages of post-tensioned, loosely bonded prestressed structures, such as improved structural performance, reduced component cross-sectional height, lighter weight, enhanced crack resistance, and self-healing properties, thereby improving the overall seismic performance of the frame structure. Post-tensioned, loosely bonded structures offer superior durability and overcome the drawback of incomplete grouting in post-tensioned structures. The unbonded prestressed tendons in the core joint area provide the structure with self-resetting capabilities, enhancing structural integrity and toughness, and reducing post-earthquake repair costs.

[0066] 2. This invention uses UHPC material with excellent performance. Applying it to the core area of ​​the node can achieve reliable connection of precast beam and column components. It can not only improve the load-bearing capacity and seismic performance of the node, but also significantly reduce the anchorage length of steel bars and steel strands, and significantly reduce the amount of stirrups used in the core area of ​​the node. This avoids the congestion of steel bars in the core area of ​​the node, and greatly improves the efficiency of the production, transportation and installation of precast beam and column components. Attached Figure Description

[0067] Figure 1 This is a structural schematic diagram of the precast prestressed concrete frame structure system based on UHPC of the present invention.

[0068] Figure 2 This is a schematic diagram of the reinforcement of a two-span frame structure according to the present invention.

[0069] Figure 3 This is a schematic diagram of the material of a two-span frame structure according to the present invention.

[0070] Figure 4 Detailed construction diagram of the intermediate layer frame edge node of the present invention

[0071] Figure 5 Isometric view of the edge node of the intermediate layer frame of the present invention

[0072] Figure 6 Detailed diagram of node construction in the intermediate layer framework of this invention.

[0073] Figure 7 Axonometric view of the nodes in the intermediate layer frame of this invention. Detailed Implementation

[0074] To make the features, objectives and advantages of the present invention easier to understand, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0075] like Figure 1-7As shown, the UHPC-connected post-tensioned and loosely bonded precast prestressed concrete frame structure system of the present invention includes a precast concrete upper column (1), a precast concrete lower column (2), a post-tensioned and loosely bonded precast prestressed concrete composite beam (3), a UHPC node core area (4), and a composite slab (17).

[0076] The precast concrete upper column (1) is provided with upper longitudinal main reinforcement (5), the precast concrete lower column (2) is provided with lower longitudinal main reinforcement (6), the post-tensioned bonded precast prestressed concrete composite beam (3) is provided with precast concrete beam (7) and beam composite layer (8) and post-tensioned bonded prestressed tendons (9), the bottom of the precast concrete beam (7) is provided with ordinary steel bars (10), the beam composite layer (8) is provided with top continuous steel bars (11), and the composite slab (17) is composed of precast concrete slab (18) and slab composite layer (19) cast on the slab;

[0077] The upper longitudinal main reinforcement (5) extends out of the bottom surface of the precast upper column (1) and is directly anchored in the core area (4) of the UHPC node; the lower longitudinal main reinforcement (6) extends out of the top surface of the precast lower column (2) and is directly anchored in the core area (4) of the UHPC node; the ordinary steel reinforcement (10) extends out of the end face of the precast concrete beam (7) and is directly anchored in the core area (4) of the UHPC node.

[0078] The slow-bonding prestressing tendons (9) include straight, broken, and curved prestressing tendons;

[0079] The loosely bonded prestressed tendon (9) in the core area of ​​the node can be bonded, bonded, partially bonded and unbonded, or unbonded;

[0080] Before pouring the beam composite layer (8), slab composite layer (19), and UHPC node core area (4), the post-tensioned, loosely bonded precast prestressed concrete composite beam (3) is constructed and verified according to the force transmission mode adapted to the ordinary concrete simply supported beam and the support setting. After pouring the node core area (4), beam composite layer (8), and slab composite layer (19), the concrete strength of the node and composite layer reaches the design requirements, and the loosely bonded prestressing tendons (9) are tensioned. After tensioning, the support is removed, and the construction stage verification is carried out according to the frame beam. During the construction verification, the calculation is carried out according to the unbonded prestressing tendons. In the serviceability limit state and the ultimate limit state, the calculation is carried out according to the bonded prestressing tendons.

[0081] The post-tensioned bonded precast prestressed concrete composite beam (3) consists of a precast concrete beam (7), a beam composite layer (8), and post-tensioned bonded prestressing tendons (9); the composite slab (17) consists of a precast concrete slab (18) and a slab composite layer (19) cast on the slab.

[0082] The post-tensioned bonded prestressing tendon (9) is pre-embedded in the precast concrete beam (7) component according to the design position, passes through the core area (4) of the UHPC node and extends beyond the core area (4) of the UHPC node at both ends. The two ends are respectively fixed with clamps (15) and anchors (16), one end is set on the outside of the column and the other end is set in the beam composite layer.

[0083] The bottom surface of the precast concrete upper column (1), the top surface of the precast concrete lower column (2), and the end face of the post-tensioned bonded precast prestressed concrete composite beam (3) are all provided with recessed grooves (U-shaped grooves can also be provided at the beam ends, and structural shear reinforcement can be provided if necessary).

[0084] The precast concrete upper column (1) is fixed in the corresponding position by a reliable support (12).

[0085] The stirrups (13) in the precast concrete upper column (1), precast concrete lower column (2), and post-tensioned loosely bonded precast prestressed concrete composite beam (3) are divided into a dense zone and a non-dense zone. The stirrups (14) in the core area (4) of the UHPC node are arranged according to the design requirements. The shear bearing capacity of the core area is calculated according to the model of the inclined compression member and truss. The steel fibers in the UHPC are considered to be equivalent to horizontal stirrups and vertical longitudinal bars, and their contribution to the shear resistance of the core area of ​​the node is considered. At the same time, the beneficial contribution of the loosely bonded prestressed tendons to the shear resistance of the node is also considered.

[0086] The top surfaces of the precast concrete beam (7) and the precast concrete slab (18) are provided with a rough surface layer.

[0087] The seismic design of this system includes the following steps:

[0088] Step 1: Design beams and columns according to existing specifications and invention patents;

[0089] Step 2: The seismic design of its nodes should be carried out according to the following method: Calculate the horizontal shear capacity V of the node. jh ;

[0090] Step 3: The diameter of each longitudinal steel bar in the beam that runs through the central column should not be greater than the smaller of 1 / 18 of the column's cross-sectional dimension in that direction and x.

[0091] A UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system, characterized by comprising the following steps:

[0092] Step 1: Construct precast concrete lower column (2), precast concrete upper column (1), precast concrete beam (7), and precast concrete slab (18); among them, the precast concrete lower column (2) and precast concrete upper column (1) with reserved extended longitudinal main bars anchored into the core area of ​​the node (4) must meet the anchorage length requirements; the precast concrete beam (7) with reserved extended ordinary steel bars (10) anchored into the core area of ​​the node (4) must also meet the anchorage length requirements; when constructing the precast concrete beam (7), the slow-bonded prestressing tendons (9) are pre-embedded in the design position, and sufficient length is reserved at both ends for convenient later tensioning;

[0093] Step 2: After the precast components have been cured, hoist the precast concrete lower column (2) and install it on the foundation, and install a sufficient number of stirrups (14) on the longitudinal main reinforcement (6) extending from the lower column (2);

[0094] Step 3: Hoist the precast concrete beam (7) to the top surface of the precast concrete lower column (2), so that the bottom surface of the precast concrete beam (7) is flush with the top surface of the precast concrete lower column (2), and place the end of the precast concrete beam (7) on the precast concrete lower column (2) and fix it with a support; wherein, the ordinary steel bars (10) extending from the precast concrete beams (7) on both sides are reasonably avoided and directly anchored in the core area of ​​the node according to the structural requirements;

[0095] Step 4: Hoist the precast concrete upper column (1) directly above the precast concrete lower column (2), and fix the precast concrete upper column (1) in the corresponding position with a reliable support (12). At this time, tie the stirrups (14) installed in step 2 together with the column longitudinal reinforcement. The longitudinal reinforcements extending from the precast concrete upper and lower columns are reasonably avoided in the core area of ​​the node and are directly anchored.

[0096] Step 5: Pass the top continuous steel bar (11) through the stirrup (13) reserved in the beam composite layer area and the node core area (4) and tie it. Then tie the pre-embedded and extended slow-bonded prestressed tendons (9) in the precast concrete beam in the node core area according to the design position. For the unbonded part of the node, a sleeve needs to be put on the slow-bonded tendon. Then pour the UHPC node core area (4) and set the template so that the UHPC will not enter the beam composite layer (8) part.

[0097] Step 6: After the core area (4) of the UHPC node has been cured to a sufficient strength, the precast concrete slab, composite slab, double T slab or secondary beam is hoisted onto the precast concrete beam (7) and fixed.

[0098] Step 7: Pour the beam composite layer (8) and slab composite layer (19);

[0099] Step 8: Tensioning the bonded prestressing tendons (9);

[0100] Step 9: Repeat the above production process to complete the tension-bonded prestressed concrete frame structure system.

[0101] The above description is merely an exemplary description of the present invention. Obviously, the specific implementation of the present invention is not limited to the above-described manner. That is, the description is not restrictive. Without departing from the inventive concept and technical solution of the present invention, the present invention can be easily improved, changed or replaced in various ways, and all such improvements and changes fall within the protection scope of the present invention.

Claims

1. A UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system, comprising a precast concrete upper column (1), a precast concrete lower column (2), a post-tensioned bonded precast prestressed concrete composite beam (3), a UHPC node core area (4), and a composite slab (17). Its features are, The precast concrete upper column (1) is provided with upper longitudinal main reinforcement (5), the precast concrete lower column (2) is provided with lower longitudinal main reinforcement (6), the post-tensioned bonded precast prestressed concrete composite beam (3) is provided with precast concrete beam (7), beam composite layer (8) and post-tensioned bonded prestressed tendons (9), the bottom of the precast concrete beam (7) is provided with ordinary steel bars (10), the beam composite layer (8) is provided with top continuous steel bars (11), and the composite slab (17) is composed of precast concrete slab (18) and slab composite layer (19) cast on the slab; The upper longitudinal main reinforcement (5) extends out of the bottom surface of the precast upper column (1) and is directly anchored in the core area (4) of the UHPC node; the lower longitudinal main reinforcement (6) extends out of the top surface of the precast lower column (2) and is directly anchored in the core area (4) of the UHPC node; the ordinary steel reinforcement (10) extends out of the end face of the precast concrete beam (7) and is directly anchored in the core area (4) of the UHPC node. The slow-bonding prestressing tendons (9) include straight, broken, and curved prestressing tendons; The loosely bonded prestressed tendon (9) in the core area of ​​the node can be bonded, bonded, partially bonded and unbonded, or unbonded; Before pouring the beam composite layer (8), slab composite layer (19), and UHPC node core area (4), the post-tensioned and loosely bonded precast prestressed concrete composite beam (3) is constructed and verified according to the force transmission mode adapted to the ordinary concrete simply supported beam and the support setting. After pouring the node core area (4), beam composite layer (8), and slab composite layer (19), the concrete strength of the node and composite layer reaches the design requirements, and the loosely bonded prestressing tendons (9) are tensioned. After tensioning, the support is removed, and the construction stage verification is carried out according to the frame beam. During the construction verification, the calculation is carried out as unbonded prestressing tendons. In the serviceability limit state and bearing capacity limit state, the calculation is carried out as bonded prestressing tendons. The post-tensioned bonded prestressing tendon (9) is pre-embedded in the precast concrete beam (7) component according to the design position, passes through the core area (4) of the UHPC node and extends out of the core area (4) of the UHPC node at both ends. It is fixed with clamps (15) and anchors (16) at both ends respectively, with one end set on the outside of the column and the other end set in the beam composite layer. The core areas of the edge nodes, middle nodes and corner nodes of the post-tensioned and bonded precast prestressed concrete frame structure system are all UHPC node core areas (4); The stirrups in the core area (4) of the UHPC node are arranged according to the design requirements. The shear bearing capacity calculation of the core area considers the steel fibers in the UHPC as equivalent to horizontal stirrups and vertical longitudinal bars, and considers their contribution to the shear resistance of the core area of ​​the node. At the same time, the beneficial contribution of the loosely bonded prestressed tendons to the shear resistance of the node is also considered. The construction method of the post-tensioned bonded precast prestressed concrete frame structure system includes: The end of the precast concrete beam (7) is placed on the precast concrete lower column (2), and the precast concrete upper column (1) is hoisted to the top of the precast concrete lower column (2). The area enclosed between the precast concrete beam and the precast concrete lower and upper columns is the core area of ​​the UHPC node.

2. The UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system according to claim 1, characterized in that, The post-tensioned bonded precast prestressed concrete composite beam (3) consists of a precast concrete beam (7), a beam composite layer (8), and post-tensioned bonded prestressing tendons (9); the composite slab (17) consists of a precast concrete slab (18) and a slab composite layer (19) cast on the slab.

3. The UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system according to claim 1, characterized in that, The bottom surface of the precast concrete upper column (1), the top surface of the precast concrete lower column (2), and the end face of the post-tensioned bonded precast prestressed concrete composite beam (3) are all provided with recessed grooves or U-shaped grooves.

4. The UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system according to claim 1, characterized in that, The stirrups in the precast concrete upper column (1), precast concrete lower column (2), and post-tensioned bonded precast prestressed concrete composite beam (3) are divided into a dense zone and a non-dense zone.

5. The UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system according to claim 1, characterized in that, The top surfaces of the precast concrete beam (7) and the precast concrete slab (18) are provided with a rough surface layer.

6. The construction method of the UHPC-connected post-tensioned bonded precast prestressed concrete frame structure system according to any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Construct precast concrete lower column (2), precast concrete upper column (1), precast concrete beam (7), and precast concrete slab (18); among them, the precast concrete lower column (2) and precast concrete upper column (1) with reserved extended longitudinal main bars anchored into the core area of ​​the node (4) must meet the anchorage length requirements; the precast concrete beam (7) with reserved extended ordinary steel bars (10) anchored into the core area of ​​the node (4) must also meet the anchorage length requirements; when constructing the precast concrete beam (7), the slow-bonded prestressing tendons (9) are pre-embedded in the design position, and sufficient length is reserved at both ends for convenient later tensioning; Step 2: After the precast components have been cured, hoist the precast concrete lower column (2) and install it on the foundation, and install a sufficient number of stirrups on the longitudinal main reinforcement (6) extending from the lower column (2); Step 3: Hoist the precast concrete beam (7) to the top surface of the precast concrete lower column (2), so that the bottom surface of the precast concrete beam (7) is flush with the top surface of the precast concrete lower column (2), and place the end of the precast concrete beam (7) on the precast concrete lower column (2) and fix it with a support; wherein, the ordinary steel bars (10) extending from the precast concrete beams (7) on both sides are reasonably avoided and directly anchored in the core area of ​​the node according to the structural requirements; Step 4: Hoist the precast concrete upper column (1) directly above the precast concrete lower column (2), and fix the precast concrete upper column (1) in the corresponding position with a reliable support (12). At this time, tie the stirrups installed in step 2 together with the column longitudinal reinforcement. The longitudinal reinforcements extending from the precast concrete upper and lower columns should be reasonably avoided in the core area of ​​the node and directly anchored. Step 5: Pass the top continuous steel bar (11) through the stirrups reserved in the beam composite layer area and the node core area (4) and tie it. Then tie the pre-embedded and extended slow-bonding prestressed tendons (9) in the precast concrete beam in the node core area according to the design position. For the unbonded part of the node, a sleeve needs to be put on the slow-bonding tendon. Then pour the UHPC node core area (4) and set the template so that the UHPC will not enter the beam composite layer (8) part. Step 6: After the core area (4) of the UHPC node has been cured to a sufficient strength, the precast concrete slab, composite slab, double T slab or secondary beam is hoisted onto the precast concrete beam (7) and fixed. Step 7: Pour the beam composite layer (8) and slab composite layer (19); Step 8: Tensioning the bonded prestressing tendons (9); Step 9: Repeat the above production process to complete the tension-bonded prestressed concrete frame structure system.

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