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

Abstract

The application discloses a UHPC connected post-tensioned bonded precast prestressed concrete frame structure system, which comprises a precast concrete upper column, a precast concrete lower column, a post-tensioned bonded precast prestressed concrete composite beam, a UHPC node core area and a composite slab. The upper longitudinal main reinforcement extends out of the bottom surface of the precast upper column and is directly anchored in the UHPC node core area, the lower longitudinal main reinforcement extends out of the top surface of the precast lower column and is directly anchored in the UHPC node core area, and the ordinary steel reinforcement extends out of the end surface of the precast concrete beam and is directly anchored in the UHPC node core area. The structure system not only is convenient and fast in on-site construction and improves the component installation efficiency, but also can greatly reduce the steel anchoring length, greatly reduce the amount of stirrups in the node core area, avoid the congestion of the steel in the node core area, reduce the component section height, reduce the self weight, improve the component crack resistance and bearing capacity, and thus improve the seismic performance of the overall frame structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of prefabricated prestressed assembly type building construction, in particular to a UHPC connected post-tensioned bonded prefabricated prestressed concrete frame structure system and a design and construction method thereof. BACKGROUND

[0002] The construction efficiency of cast-in-place structures is low, and the energy loss is high, and many limitations, which gradually cannot meet the development requirements of building industrialization. Prefabricated assembly type buildings have become the development direction of building industrialization due to their advantages of fast construction speed, factory production of components, reduction of on-site wet work and environmental pollution. After years of development and promotion, prefabricated assembly type concrete structures have been widely researched and used.

[0003] Prefabricated assembly type concrete frame structure refers to the structure in which beam and column components are prefabricated in a prefabrication plant and transported to the construction site for connection to form an overall structure. Compared with cast-in-place concrete structures, it has the advantages of fast construction speed, easy guarantee of component quality, good quality, less environmental pollution, saving of labor cost, and saving of a large number of formwork and support, etc., and is a structure form with very broad prospects. For wet connection assembly type concrete frame structures, the joint construction form which is easy to construct and effectively guarantees the integrity is the key to the popularization and application. However, from the past earthquake disasters, the assembly type structure is severely damaged in the earthquake, and it is difficult to achieve the same seismic performance as the cast-in-place structure. In order to improve the integrity and reliability of the assembly type concrete frame joint connection and achieve or even exceed the seismic performance of the cast-in-place concrete structure, prestressing technology and UHPC material (Ultra High Performance Concrete, ultra high performance concrete) are introduced into the assembly type structure.

[0004] Post-tensioned bonded prestressed assembly type concrete structure is a structure formed by assembling prefabricated components together to work together through tensioning of prestressed reinforcement and grouting. It has the characteristics of post-tensioned bonded prestressed concrete structure and assembly type structure. The internal stress generated by prestress in the concrete section can partially or completely offset the stress in the section under the use load, delay the occurrence of cracks and improve the stiffness of the component. When unloaded, the cracks can be partially or completely closed, and the elastic recovery performance of the structure is good. At the same time, prestressed concrete can fully utilize the material strength of prestressed reinforcement and concrete, and reduce the self-weight of the structure. The application of prestress helps to improve the performance and integrity of the assembly type structure, and promotes the application of assembly type structure in large-span and heavy-load structures.

[0005] UHPC has excellent bonding performance, which can greatly reduce the anchorage length of steel bars and steel strands; it has high strength, which can reduce the amount of stirrups in the core area of the joint; using UHPC in the core area of the joint can make the structure simple and the overall framework good. The prestressed structure has excellent stress performance, and the application of UHPC in the core area of the joint forms a prefabricated prestressed framework structure. Further research on this structure is beneficial to the further promotion and application of prefabricated prestressed concrete framework structure. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, combine the excellent performance of UHPC, and propose a UHPC connected post-tensioned bonded prefabricated prestressed concrete framework structure system and its design and construction method. It combines three traditional structures of post-tensioned bonded prestressed structure, prefabricated structure and composite structure, and uses UHPC high-performance material, so as to improve the seismic performance of prefabricated concrete framework structure.

[0007] The advantages of the present application mainly lie in the connection technology of prefabricated concrete beam-column components and the steel bar connection technology between components. In terms of component connection technology, the beam-column components are connected by UHPC with excellent performance to form a UHPC joint core area, which is more conducive to realizing the seismic fortification requirements of strong joints and weak components, thereby improving the ductility of beam-column joints and improving the seismic performance of the overall framework structure. In terms of steel bar connection technology, the steel bars between beam-column components only need to be simply overlapped, and the overlap length is very small, thereby greatly saving the production time of prefabricated components and the installation time on site. Therefore, the UHPC connected post-tensioned bonded prefabricated prestressed concrete framework structure system and its design and construction method proposed by the present application meet the green development strategy of China's building industrialization.

[0008] The technical problems solved by the present application can be solved by using the following technical solutions:

[0009] A UHPC connected post-tensioned bonded prefabricated prestressed concrete framework structure system, comprising a prefabricated concrete upper column, a prefabricated concrete lower column, a post-tensioned bonded prefabricated prestressed concrete composite beam, a UHPC joint core area and a composite slab.

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

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

[0012] The post-tensioned bonded prefabricated prestressed concrete composite beam also includes a fully prefabricated prestressed concrete beam; the bonded prestressed tendon includes a straight line, a broken line, and a curved prestressed tendon;

[0013] The bonded prestressed tendon in the node core area can be bonded, bonded, or partially bonded and unbonded, and unbonded;

[0014] The post-tensioned bonded prefabricated prestressed concrete composite beam is calculated according to the construction of a simple supported beam and support before pouring the beam composite layer, the plate composite layer, and the UHPC node core area, and after pouring the node core area, the beam composite layer, and the plate composite layer, the node and the composite layer concrete strength reaches the design requirement, the bonded prestressed tendon is tensioned, after tensioning, the support is removed, and the construction stage calculation is carried out according to the unbonded frame beam; for the node core area partially bonded and unbonded, and unbonded, under the normal use limit state, the calculation is carried out according to the effective prestress, under the ultimate bearing limit state, the stress increment of the unbonded tendon is considered, and under the seismic load, the recovery performance provided by the unbonded tendon is considered.

[0015] Further, the post-tensioned bonded prefabricated prestressed concrete composite beam is composed of a prefabricated concrete beam, a beam composite layer, and a post-tensioned bonded prestressed tendon.

[0016] Further, the post-tensioned bonded prestressed tendon is arranged in a corrugated pipe pre-buried in the prefabricated concrete beam component and passes through the corrugated pipe pre-buried in the beam composite layer and the UHPC node core area and extends out of the UHPC node core area at both ends, and clamps and anchors are respectively fixed at both ends.

[0017] Further, the bottom surface of the prefabricated concrete upper column, the top surface of the prefabricated concrete lower column, and the end surface of the post-tensioned bonded prefabricated prestressed concrete composite beam are provided with recesses (U-shaped grooves can also be provided at the beam end, and construction shear reinforcement can be provided if necessary).

[0018] Further, the prefabricated concrete upper column is fixed in the corresponding position by reliable support.

[0019] Further, the stirrups in the precast concrete upper column, the precast concrete lower column and the post-tensioned bonded precast prestressed concrete composite beam are divided into the encryption area and the non-encryption area, the stirrups in the UHPC node core area are arranged according to the design requirement, the shear bearing capacity of the core area is calculated according to the inclined strut and truss model, and the steel fibers in the UHPC are equivalent to the horizontal stirrup and the vertical longitudinal reinforcement, the contribution of the steel fibers to the shear of the node core area is considered, and the beneficial contribution of the bonded prestressed reinforcement to the shear of the node is considered.

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

[0021] The application also provides a design method of the system, comprising the following steps:

[0022] Step 1: the beam and the column are designed according to the existing specification and the invention patent;

[0023] Step 2: the seismic design of the node needs to be carried out according to the following method, and the horizontal shear bearing capacity V of the node is calculated jh :

[0024] The shear bearing capacity of the frame beam-column node should meet the following provisions:

[0025]

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

[0027] V ch =0.95·A·B·C·b j ·h c

[0028] V sh =α2·A sjh ·f yj

[0029]

[0030] V max =γ1·γ2·γ3·0.25·f c '·b j ·h c ≤2·V ch

[0031] V fh =ηλ f h b b c

[0032]

[0033] In the formula: A sjh —Area of ​​stirrups in the core area of ​​the node;

[0034] f yj —Design value of the yield strength of the stirrups in the core area of ​​the node;

[0035] b j — Node effective width;

[0036] h c —Column height;

[0037] N pe —The effective prestressing resultant force of the prestressing tendons acting in the core area of ​​the node;

[0038] ρ — Column reinforcement ratio;

[0039] b b —Liang Kuan;

[0040] h b —Liang Gao;

[0041] f c —Design value of axial compressive strength of concrete;

[0042] η—Effective coefficient of UHPC steel fiber;

[0043] l—Length of UHPC steel fibers;

[0044] d—Diameter of UHPC steel fibers;

[0045] V f —UHPC steel fiber volume content;

[0046] 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:

[0047]

[0048] In the formula: —Design axial compression ratio;

[0049] 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.

[0050] A s —Total area of ​​longitudinal reinforcement bars at the top and bottom of the beam.

[0051] A UHPC connected post-tensioned bonded precast prestressed concrete frame structure system, comprising the following steps:

[0052] Step 1: making precast concrete lower columns, precast concrete upper columns, precast concrete beams, and precast concrete slabs; wherein the precast concrete lower columns and the precast concrete upper columns have sufficient anchoring lengths for anchoring the longitudinal reinforcement into the node core area; the precast concrete beams have sufficient anchoring lengths for anchoring the ordinary reinforcement into the node core area; and corrugated pipes are embedded in the precast concrete beams according to the design positions of the prestressed reinforcement;

[0053] Step 2: after the precast components are completed, the precast concrete lower columns are hoisted and installed on the foundation, and then a proper number of stirrups are installed on the extended longitudinal reinforcement;

[0054] Step 3: the precast concrete beams are hoisted to the top surface of the precast concrete lower columns, the bottom surface of the precast concrete beams is flush with the top surface of the precast concrete lower columns, the end portions of the precast concrete beams are placed on the precast concrete lower columns and fixed by supports; wherein the reinforcement of the precast concrete beams on both sides is reasonably avoided in the node core area and directly anchored;

[0055] Step 4: the precast concrete upper columns are hoisted to directly above the precast concrete lower columns, the precast concrete upper columns are fixed in the corresponding positions by reliable supports, and the stirrups installed in step 2 are tied; wherein the reinforcement of the precast concrete upper and lower columns is reasonably avoided in the node core area and directly anchored;

[0056] Step 5: the top longitudinal reinforcement is passed through the reserved stirrups in the beam composite layer area and the node core area, tied, and a section of corrugated pipe is embedded in the node core area to form a whole with the corrugated pipe embedded in the precast concrete beam, and then the UHPC node core area is poured, and the formwork is arranged so that the UHPC does not enter the beam composite layer part;

[0057] Step 6: after the UHPC node core area is cured to sufficient strength, the precast concrete flat slabs, composite slabs, double-T slabs, or secondary beams are hoisted to the precast concrete beams and fixed;

[0058] Step 7: pouring the beam composite layer and the slab composite layer;

[0059] Step 8: passing the reinforcement in the corrugated pipe and tensioning the prestressed reinforcement, and grouting in the corrugated pipe of the bonded part of the beam and the node, and not grouting in the unbonded prestressed reinforcement part of the node;

[0060] Step 9: repeating the above manufacturing process to complete the post-tensioned bonded precast prestressed concrete frame structure system.

[0061] Compared with the prior art, the advantages of the present application are:

[0062] 1.The present application combines prefabricated concrete structure and post-tensioned bonded prestressed structure together, on the basis of the advantages of prefabricated structure construction convenient and fast, good construction quality, energy saving and environmental protection, combined with post-tensioned bonded prestressed structure, which can improve the structural performance, reduce the cross-section height of the component, reduce the self-weight, improve the component crack resistance and self-recovery advantage, so as to improve the seismic performance of the overall frame structure. The unbonded prestressed reinforcement in the node core area provides self-resetting ability for the structure, enhances the integrity and toughness of the structure, and reduces the repair cost after the earthquake.

[0063] 2.The present application adopts UHPC material with excellent performance, which is applied in the node core area, can realize reliable connection of prefabricated beam column component, not only can improve the bearing capacity and seismic performance of the node, but also can greatly reduce the anchorage length of steel bar and steel strand, and can significantly reduce the amount of stirrup in the node core area, so as to avoid the congestion of steel bars in the node core area, and greatly improve the production, transportation and installation efficiency of prefabricated beam column component. BRIEF DESCRIPTION OF DRAWINGS

[0064] Figure 1 The structural schematic diagram of the prefabricated prestressed concrete frame structure system based on UHPC of the present application

[0065] Figure 2 The reinforcement schematic diagram of a two-span frame structure of the present application

[0066] Figure 3 The material schematic diagram of a two-span frame structure of the present application

[0067] Figure 4 The detailed structure diagram of the edge node of the intermediate layer frame of the present application

[0068] Figure 5 The axonometric view of the edge node of the intermediate layer frame of the present application

[0069] Figure 6 The detailed structure diagram of the middle node of the intermediate layer frame of the present application

[0070] Figure 7 The axonometric view of the middle node of the intermediate layer frame of the present application DETAILED DESCRIPTION

[0071] In order to make the features, objects and advantages of the present application more easily understood, the present application is further described below in combination with the drawings and specific embodiments.

[0072] As Figures 1-7The application discloses a UHPC connected post-tensioned bonded precast prestressed concrete frame structure system, which comprises 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).

[0073] The precast concrete upper column (1) is internally provided with upper longitudinal main reinforcement (5), the precast concrete lower column (2) is internally provided with lower longitudinal main reinforcement (6), the post-tensioned bonded precast prestressed concrete composite beam (3) is internally provided with a precast concrete beam (7), a beam composite layer (8) and post-tensioned bonded prestressed reinforcement (9), the bottom of the precast concrete beam (7) is provided with ordinary reinforcement (10), the beam composite layer (8) is internally provided with top-through steel bars (11), and the composite slab (17) is composed of a precast concrete slab (18) and a slab composite layer (19) poured on the slab.

[0074] The upper longitudinal main reinforcement (5) extends out of the bottom surface of the precast upper column (1) and is directly anchored in the UHPC node core area (4), the lower longitudinal main reinforcement (6) extends out of the top surface of the precast lower column (2) and is directly anchored in the UHPC node core area (4), and the ordinary reinforcement (10) extends out of the end surface of the precast concrete beam (7) and is directly anchored in the UHPC node core area (4).

[0075] The post-tensioned bonded precast prestressed concrete composite beam (3) also comprises a fully precast prestressed concrete beam, the bonded prestressed reinforcement (9) comprises straight-line, zigzag and curved prestressed reinforcement,

[0076] The bonded prestressed reinforcement (9) in the node core area (4) can be bonded, bonded or partially bonded and unbonded, or unbonded.

[0077] The post-tensioned bonded precast prestressed concrete composite beam (3) is subjected to construction checking calculation according to the force transmission mode of a common concrete simply-supported beam and support before pouring the beam composite layer (8), the slab composite layer (19) and the UHPC node core area (4), after pouring the node core area (4), the beam composite layer (8) and the slab composite layer (19), the node and the composite layer concrete strength reaches the design requirement, the bonded prestressed reinforcement (9) is tensioned, after the tensioning is completed, the support is removed, and the construction stage checking calculation is performed according to the unbonded frame beam; for the node core area partially bonded and unbonded, or unbonded, the effective prestress is used for calculation in the normal use limit state, the stress increment of the unbonded reinforcement is considered in the ultimate bearing limit state, and the restoring performance provided by the unbonded reinforcement is considered under the seismic load.

[0078] The post-tensioned bonded precast prestressed concrete composite beam (3) is composed of a precast concrete beam (7), a beam composite layer (8), and a post-tensioned bonded prestressed tendon (9); and the composite slab (17) is composed of a precast concrete slab (18) and a slab composite layer (19) poured on the slab.

[0079] The post-tensioned bonded prestressed tendon (9) is arranged in a corrugated pipe pre-buried in the precast concrete beam (7) component, passes through the corrugated pipe pre-buried in the beam composite layer (8) and the UHPC node core area (4), and extends out of the UHPC node core area (4) at both ends, and clamps (15) and anchors (16) are respectively arranged at both ends.

[0080] The bottom surface of the precast concrete upper column (1), the top surface of the precast concrete lower column (2), and the end surface of the post-tensioned bonded precast prestressed concrete composite beam (3) are all provided with a recessed groove (a U-shaped groove can also be arranged at the beam end, and constructional shear reinforcement can be arranged if necessary).

[0081] The precast concrete upper column (1) is fixed in the corresponding position by reliable support (12).

[0082] The stirrups (13) in the precast concrete upper column (1), the precast concrete lower column (2), and the post-tensioned bonded precast prestressed concrete composite beam (3) are divided into a densified area and a non-densified area, the stirrups (14) in the UHPC node core area (4) are arranged according to design requirements, the shear bearing capacity of the core area is calculated according to the inclined strut and truss model, and the steel fibers in the UHPC are equivalent to horizontal stirrups and vertical longitudinal reinforcement, and their contribution to the shear resistance of the node core area is considered, and the beneficial contribution of the bonded prestressed tendon to the shear resistance of the node is also considered.

[0083] The top surfaces of the precast concrete beam (7) and the precast concrete slab (18) are provided with a rough surface layer.

[0084] The seismic design of the system includes the following steps:

[0085] Step 1: The beam and column are designed according to the existing specifications and invention patents.

[0086] Step 2: The seismic design of the node needs to be carried out according to the following method: the horizontal shear bearing capacity V of the node is calculated jh ;

[0087] Step 3: The diameter of each longitudinal steel bar penetrating the middle column should not be greater than the smaller value of 1 / 18 of the sectional size of the column in that direction and x.

[0088] A UHPC connected post-tensioned bonded precast prestressed concrete frame structure system, characterized by comprising the following steps:

[0089] Step 1: make precast concrete lower column (2), precast concrete upper column (1), precast concrete beam (7), precast concrete slab (18); wherein the precast concrete lower column (2), precast concrete upper column (1) extends the longitudinal reinforcement anchorage into the node core area (4) needs to reserve enough anchorage length; precast concrete beam (7) extending ordinary steel (10) anchorage into the node core area (4) needs to reserve enough anchorage length; precast concrete beam (7) in accordance with the design position of pre-stressed tendon (9) embedded bellows;

[0090] Step 2: after the precast components are completed, hoist the precast concrete lower column (2) and install it on the foundation, then install the appropriate number of stirrups (14) on the extending longitudinal reinforcement (6);

[0091] Step 3: hoist the precast concrete beam (7) to the top surface of the precast concrete lower column (2), make the bottom surface of the precast concrete beam (7) flush with the top surface of the precast concrete lower column (2), make the end of the precast concrete beam (7) rest on the precast concrete lower column (2) and be fixed with support; wherein the steel bars (10) extending from both sides of the precast concrete beam (7) are reasonably avoided in the node core area and directly anchored;

[0092] Step 4: hoist the precast concrete upper column (1) to the directly above the precast concrete lower column (2), fix the precast concrete upper column (1) in the corresponding position with reliable support (12), and bind the stirrups (14) installed in step 2; wherein the precast concrete upper and lower column extending steel bars are reasonably avoided in the node core area and directly anchored;

[0093] Step 5: pass the top longitudinal steel bar (11) through the reserved stirrup (13) in the beam composite layer area and the node core area (4) and bind them well, and embed a section of bellows in the node core area to form a whole with the bellows embedded in the precast concrete beam (7), then pour the UHPC node core area (4), and set the formwork so that the UHPC does not enter the beam composite layer (8) part;

[0094] Step 6: after the UHPC node core area (4) is cured to sufficient strength, hoist the precast concrete flat slab, composite slab, double T slab or secondary beam to the precast concrete beam (7) and fix it;

[0095] Step 7: pour the beam composite layer (8) and the slab composite layer (19);

[0096] Step 8: pass the steel bar in the bellows and tension the pre-stressed tendon (9), grout in the bellows of the beam and the node with adhesive part, and do not grout for the node without adhesive pre-stressed tendon part;

[0097] Step 9: repeat the above manufacturing process to complete the post-tensioned precast prestressed concrete frame structure system.

[0098] The above is only an exemplary description of the present application, and it is obvious that the specific implementation of the present application is not limited by the above manner, i.e., the description is not restrictive, and the present application can be easily improved, changed or replaced without departing from the method concept and technical solution of the present application, and these improvements and changes all belong to the protection scope of the present application.

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 post-tensioned bonded precast prestressed concrete composite beam (3) also includes a fully precast prestressed concrete beam; the bonded prestressed tendons (9) include straight, broken, and curved prestressed tendons; The bonded prestressed tendons (9) in the node core area (4) can be bonded, partially bonded, unbonded, or unbonded; Before pouring the beam composite layer (8), slab composite layer (19) and UHPC node core area (4), the post-tensioned bonded precast prestressed concrete composite beam (3) is constructed 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 bonded prestressed tendons (9) are tensioned. After tensioning, the support is removed, and the construction stage is verified as an unbonded frame beam. For the bonded and unbonded parts of the node core area, the calculation is based on the effective prestress under the normal serviceability limit state. Under the ultimate bearing limit state, the stress increment of the unbonded tendons is considered. Under seismic load, the recovery performance provided by the unbonded tendons is considered. The post-tensioned bonded prestressed tendon (9) is set in the corrugated pipe embedded in the precast concrete beam (7) component, and passes through the corrugated pipe embedded in the beam composite layer (8) and the UHPC node core area (4) and extends out of the UHPC node core area (4) at both ends. The two ends are respectively fixed with clamps (15) and anchors (16). The core areas of the edge nodes, middle nodes and corner nodes of the post-tensioned 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 bonded prestressed tendons to the core area 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 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 longitudinal reinforcement extending from the precast concrete lower column (2) and precast concrete upper column (1) into the core area (4) of the node needs to be reserved with sufficient anchorage length; the ordinary steel bars (10) extending from the precast concrete beam (7) into the core area (4) of the node need to be reserved with sufficient anchorage length; corrugated pipes are pre-embedded in the precast concrete beam (7); Step 2: After the precast components are made, hoist the precast concrete lower column (2) and install it on the foundation, and then install an appropriate number of stirrups on the extended longitudinal main bars (6); 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 steel bars (10) extending from the precast concrete beams (7) on both sides are reasonably avoided in the core area of ​​the node and directly anchored; Step 4: Hoist the precast concrete upper column (1) directly above the precast concrete lower column (2), fix the precast concrete upper column (1) in the corresponding position with a reliable support (12), and tie the stirrups installed in Step 2; wherein, the protruding steel bars of the precast concrete upper and lower columns are reasonably avoided in the core area of ​​the node and are 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. Embed a corrugated pipe in the node core area to form an integral whole with the corrugated pipe embedded in the precast concrete beam (7). Then pour the UHPC node core area (4) and set the template so that the UHPC will not enter the beam composite layer (8). 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: Thread and tension the prestressing tendons in the corrugated pipe (9), and grout the corrugated pipes in the bonded parts of the beam and joint. Do not grout the unbonded prestressing tendon parts of the joint. Step 9: Repeat the above production process to complete the bonded prestressed concrete frame structure system.

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